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HomeMy WebLinkAboutDrainage Reports - 05/18/2022 (4)kimley-horn.com 4582 South Ulster Street, Suite 1500, Denver, CO 80237 303 228 2300 DRAINAGE REPORT COVER LETTER To: City of Fort Collins Matt Simpson, P.E., CFM Development Review Engineer From:Dan Skeehan, P.E. Kimley-Horn and Associates, Inc Date: April 14, 2021 Subject:Mulberry Connection, PDP190015 Drainage Report Cover Letter Kimley-Horn and Associates, Inc. (Kimley-Horn) is submitting this Drainage Report Cover Letter for the above referenced project. The purpose of this letter is to serve as an outline for the proposed development and associated drainage. PROJECT DESCRIPTION The proposed Mulberry Connection Project is located within the Northeast Quarter of Section 9, Township 7 North, Range 68 West of the Sixth Principal Meridian, City of Fort Collins, County of Larimer, Colorado. A vicinity map is provided below. City of Fort Collins Approved Plans Approved by: Date: Matt Simpson 05/18/2022 Page 2 kimley-horn.com 4582 South Ulster Street, Suite 1500, Denver, Colorado, 80237 303 228 2300 The site is approximately 13 acres and is existing farm land. The proposed site includes two industrial buildings with associated parking and landscape improvements. Drainage improvements include two proposed rain gardens, proposed underground water quality treatment, and a proposed detention pond. A variance is being requested to allow for an inflow infiltration basin at the inflow into the detention pond due to existing grades within the project site and along the adjacent boundaries. “I hereby attest that this report for the final drainage design for the Mulberry Connection was prepared by me or under my direct supervision, in accordance with the provisions of the Fort Collins Stormwater Criteria Manual. I understand that the City of Fort Collins does not and will not assume liability for drainage facilities designed by others.” SIGNATURE: _________________________________ Dan Skeehan, P.E. Registered Professional Engineer State of Colorado No. 46391 ATTACHMENTS Final Drainage Report City of Fort Collins Mulberry Connection (Redman Drive and I-25 Frontage Road) Final Drainage Report APRIL 2021 | VERSION 1 Prepared By: 4582 South Ulster Street, Suite 1500 Denver, CO 80237 Dan Skeehan Registered Professional Engineer State of Colorado No. 46391 Final Drainage Report Mulberry Connection – Fort Collins, Colorado 2 INTRODUCTION The proposed Mulberry Connection Project is located within the Northeast Quarter of Section 9, Township 7 North, Range 68 West of the Sixth Principal Meridian, City of Fort Collins, County of Larimer, Colorado. The site is bound by: North: Existing Farmland East: Interstate 25 (“I-25”) Frontage Road South: Redman Drive West: Existing Farmland A vicinity map is provided below. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 3 PROPOSED DEVELOPMENT The site is approximately 13.05 acres and is existing farmland. The proposed site includes two industrial buildings with associated parking and landscape improvements. EXISTING SITE INFORMATION The Site is located within the Boxelder Creek and Cooper Slough Basins. The Master Plan for these basins is currently being updated, according to the City of Fort Collins website. According to the Problem Identification Map provided on the City of Fort Collins website for the Boxelder and Cooper Slough Basin, the Site is not within a high or moderate risk floodplain. The Flooding Solutions Map indicates that upgrades to pipes and open channels are recommended south of the Site along E. Mulberry Street. No flooding, water quality, nor Master Plan improvements are recommended within the vicinity of the Site. The soil on the site is primarily Nunn loam and Garrett loam, which are classified as Hydrologic Soil Group C and B, respectively. The soil Classification Map can be found in Appendix A. This Site is a part of the Boxelder Creek & Cooper Slough Master Drainage Plan, which is currently under revision and has not been referenced in this design. The existing site is utilized as agricultural land with ground cover primarily made up of crop. According to the Geotechnical Evaluation performed by Ninyo & Moore on July 2, 2019, groundwater was encountered at depths ranging between approximately 8.5 to 12 feet below ground surface. HISTORIC DRAINAGE The existing Site is relativity flat with slopes ranging from 0.5% to 3%. There are currently no existing on- site water quality or detention improvements. The majority of the site currently slopes to the southwest, conveying water into an existing roadside ditch adjacent to Redman Drive, which discharges into Cooper Slough approximately 600 feet west of the Site. The property directly north of the Site is collected by an existing drainage ditch along the northern property line, routing all discharges around the Site. I-25 Frontage Road is adjacent to the Site to the east. The width of the Frontage Road drains west into an existing drainage ditch adjacent to the Site in the existing condition. The site is located within City of Fort Collins Federal Emergency Management Agency (FEMA) Flood Insurance Rate Map Number 08069C0984H and the property being developed is designated as an area outside of the 100-year floodplain. The updated FEMA maps is included in Appendix A. Per the FEMA Flood Insurance Rate Map and City of Fort Collins Problem Identification Map, the Site is not within a 100-year floodplain and therefore additional analysis and permitting will not be required. DESIGN CRITERIA The City of Fort Collins “Stormwater Criteria Manual, December 2018 Edition,” (Criteria Manual) and the “Urban Drainage and Flood Control District Urban Storm Drainage Criteria Manual” Volumes 1, 2, and 3 (Drainage Manual), with latest revisions, were used to prepare the storm calculations. Weighted impervious values were calculated and used for the site area in accordance with the Criteria Manual and Drainage Manual. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 4 This Site is a part of the Boxelder Creek & Cooper Slough Master Drainage Plan, which is currently under revision. Existing storm sewer infrastructure is not present on the Site. An existing drainage ditch is present on both sides (north and south) of Redman Drive, in addition to the existing concrete irrigation ditch on the adjacent property to the north. An existing drainage ditch adjacent to the Site to the east collects the Frontage Road runoff. Hydrologic Criteria The 2-year and 100-year storm event were evaluated for this Site. Rainfall intensity values provided in the Criteria Manual were utilized for the analysis. Impervious values for pavement, roof, and landscape area were taken from the Criteria Manual. Runoff coefficients were calculated per the Criteria Manual. The Rational Method was utilized to calculate the peak runoff values for the minor and major storm event. Peak runoff values were calculated for the existing conditions of the Site, which the 2-year existing peak runoff informed the allowable release from the Site in the proposed conditions in the 100-year storm event. Topographic survey of the Site was utilized to delineate existing sub-basins for the Site. An Existing Drainage Map is provided in Appendix B and all hydrologic calculations are provided in Appendix C. The proposed site layout and grading was utilized to delineate sub-basins for the proposed condition, as shown in the Proposed Drainage Map included in Appendix B. Peak runoff values for the proposed sub- basins were calculated using the Rational Method. Hydrologic calculations are provided in Appendix C. Hydraulic Criteria Water Quality Capture Volumes for sub-basins A, B, C, and D were calculated per the methods described in the Criteria Manual. The Modified FAA Method, as described in the Criteria Manual, was utilized to calculate the required detention volume for the Site in the proposed conditions. Water quality and detention calculations are provided in Appendix D. This Final Drainage Report includes the following hydraulic calculations: inlet calculations; pipe capacity calculations utilizing Bentley StormCAD. Sizing of the overflow spillways have been done per the methods described in the Criteria Manual. All hydraulic calculations are included in Appendix D. DRAINAGE PLAN GENERAL CONCEPT The Site in the proposed conditions was divided into four major onsite sub-basins which are described in greater detail in the following section. BMPs were selected utilizing the four-step process outlined in Volume 3, Chapter 1, Section 4 of the Drainage Manual: 1. Employ runoff reduction practices (Minimize Directly Connected Impervious Area) - The redevelopment of an urban site provides limited opportunities to employ runoff reduction practices. The Site has been developed to install landscaping wherever pavement (or building) is not required. Additionally, impervious areas have been disconnected from storm sewer infrastructure at all feasible locations, and are routed into the proposed rain gardens within basins A and C. 2. Implement BMPs that provide a water quality capture volume with a slow release – 12.01 acres will be treated for the water quality capture volume (WQCV). The total on-site proposed impervious surface area is 8.92 acres (including pavement and roofs), 8.85 acre of which will be treated by bioretention or underground proprietary system. D sub-basins are directly tributary to the inflow Final Drainage Report Mulberry Connection – Fort Collins, Colorado 5 infiltration basin within the detention pond. WQCV for the D sub-basins will be treated via infiltration. Drainage basins O1, O2, O3, O4, OS1, and OS2 will not be treated for water quality, a total of 0.76 acres on-site and 1.92 acres off-site. A rain garden is proposed to treat the WQCV from sub-basin C, an underground treatment system is proposed to treat the WQCV from sub-basin B, a rain garden is proposed to treat the WQCV from sub-basin A, and the WQCV from sub-basin D will be infiltrated via the inflow infiltration basin in the detention pond, as detailed in Table 1 below. Table 1. Summary of Impervious Area Treated On-Site Sub- Basin Total Area (ac) Impervious Area (ac) Impervious Area Treated (ac) Percent Impervious Treated Water Quality Feature A 5.39 3.65 3.65 100% Rain Garden A B1 1.72 1.52 1.52 100% Underground B2 1.27 1.13 1.13 100% C 3.63 2.55 2.55 100% Rain Garden C Total to LID 12.01 8.85 8.85 100%-- D1 0.16 0.04 0.04 100% Inflow Infiltration Basin within Detention PondD20.14 0.02 0.02 100% Total to Infiltration 0.30 0.06 0.06 100%-- O1 0.52 0.00 0.00 0% Flows Off-SiteO20.07 0.03 0.00 0% O3 0.03 0.02 0.00 0% O4 0.14 0.00 0.00 0% Total Not Treated 0.76 0.05 0.00 0%-- Total On-Site 13.07 8.96 8.91 98% (percent impervious treated) 92% (percent total Site to LID) The three proposed water quality treatment areas are shown on the Proposed Drainage Map in Appendix B and calculations are provided in Appendix D. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 6 3. Stabilize streams – Not applicable. 4. Implement site specific and other source control BMPs – During construction, the site will include silt fence to reduce potential for contamination discharges at the perimeter. Site access will be provided through an area of vehicle tracking control to reduce tracking of contamination offsite which will be further controlled with street sweeping and rock socks along Redman Drive. Proposed storm sewer will have inlet protection. Additionally, diversion ditches routing water to a sediment basin will be installed at the beginning of construction. SPECIFIC DETAILS Runoff generated by three of the on-site basins (sub-basins A B, and C - 12.01 acres of the total 13.07 acres – 92% of the Site) will be routed to LID features and the WQCV treated. Runoff generated by storm events greater than the WQCV will be routed through the LID features to a proposed detention pond via proposed storm sewer infrastructure. Runoff generated by one on-site basin (sub-basin D – 0.30 acres of the total 13.07 acres – 2% of the Site) will be routed to the inflow infiltration basin within the proposed detention pond. The proposed detention pond will outfall to an existing drainage swale directly upstream of Cooper Slough and adjacent to the Site. Four on-site basins (0.76 acres – 6% of the Site) will surface flow off-site and not be treated for water quality or be detained. The 100-year release rate from the proposed detention pond was calculated to take into account the undetained flows from these basins that are not fully pervious (sub-basins O1 and O4 are fully pervious, while sub-basins O2 and O3 are accounted for in the 100-year release rate). Two offsite sub-basins are included in the drainage analysis to properly size all proposed drainage features. The Proposed Drainage Map included in Appendix B shows the onsite and offsite sub-basins and each basin is described in further detail below. Table 2 summarizes the tributary areas, impervious areas, imperviousness, and peak flows from each sub-basin. Full calculations are included in Appendix C. Sub-basin A Sub-basin A is 5.39 acres and consists of on-site parking, sidewalk, one of the buildings, and landscape areas that surface flow to proposed Rain Garden A. Water quality treatment for runoff from this sub-basin will occur within Rain Garden A. Flows above the WQCV will flow to the detention pond via two overflow spillways between Rain Garden A and the detention pond. Sub-basin B1 Sub-basin B1 is 1.72 acres and consists of on-site parking, sidewalk, loading dock, and landscaped areas. Runoff within this sub-basin surface flows to a proposed double CDOT Type 13 inlet within a proposed valley gutter. Sub-basin B2 Sub-basin B2 is 1.27 acres and consists of loading dock. Runoff within this sub-basin surface flows to a proposed double CDOT Type 13 inlet within a proposed valley gutter. Both inlets within sub-basin B will connect to the ADS Inflow Manhole. This manhole has been designed with a low-flow outlet pipe at the bottom of the structure, connected to an underground water quality facility, which will convey the WQCV. Flows over the WQCV will pond within the manhole structure to the “overflow outlet pipe”, which will convey flows to the detention pond. The invert of the overflow outlet pipe has been set at the maximum storage elevation within the underground water quality facility to store the required WQCV. The stage storage table for the ADS underground system is included in Appendix D. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 7 Sub-basin C Sub-basin C is 3.63 acres and consists of on-site parking, sidewalk, one of the buildings, and landscaped areas. Runoff within this sub-basin will surface flow east into Rain Garden C, which will provide water quality treatment. Storm events greater than the WQCV will be routed through Rain Garden C, into the proposed outlet structure and conveyed via storm pipe to the detention pond. Sub-basin D1 Sub-basin D1 is 0.16 acres and consists of on-site landscaped area and a portion of sidewalk. Runoff within this sub-basin will surface flow to a proposed CDOT Type D inlet. Flows will be routed to the proposed inflow infiltration basin within the detention pond via proposed storm sewer. Sub-basin D2 Sub-basin D2 is 0.14 acres and consists of on-site landscaped area and a portion of sidewalk. Runoff within this sub-basin will surface flow to a proposed CDOT Type D inlet. Flows will be routed to the proposed inflow infiltration basin within the detention pond via proposed storm sewer. Sub-basin O1 Sub-basin O1 is 0.52 acres and consists of on-site landscaped area. Runoff within this sub-basin will surface flow offsite and water quality treatment nor detention will be provided for this sub-basin. Sub-basin O2 Sub-basin O2 is 0.07 acres and consists of on-site landscaped area and a portion of the west access drive. Runoff within this sub-basin will surface flow offsite to Redman Drive. Water quality treatment nor detention will be provided for this sub-basin. Sub-basin O3 Sub-basin O3 is 0.03 acres and consists of on-site landscaped area and a portion of the east access drive. Runoff within this sub-basin will surface flow offsite to Redman Drive. Water quality treatment nor detention will be provided for this sub-basin. Sub-basin O4 Sub-basin O4 is 0.14 acres and consists of on-site landscaped area. Runoff within this sub-basin will surface flow offsite to the I-25 Frontage Road. Runoff will be collected in the proposed curb and gutter and will be routed south across Redman Drive via a proposed valley gutter. Runoff will enter an existing drainage swale south of the intersection via a 2-foot curb cut. Water quality treatment nor detention will be provided for this sub-basin. Sub-basin OS1 Sub-basin OS1 is 0.91 acres and consists of off-site landscaped area, sidewalk, and I-25 Frontage Road. Runoff within this sub-basin will flow to the proposed curb and gutter, following historic drainage patterns. Flows will be routed around the corner and down Redman Drive, maintain historic drainage patterns. Runoff will flow west down Redman Drive along the proposed curb and gutter and driveway crosspans, entering Final Drainage Report Mulberry Connection – Fort Collins, Colorado 8 the existing swale on the north side of the roadway at the western limits of the project. The Street Capacity section of this report includes a detailed description of flows in the roadway. Water quality treatment nor detention will be provided for this sub-basin on the proposed site. Additionally, this basin is not included as a part of the total Site improvement area, as proposed off-site improvements will improve existing conditions and maintain historic drainage patterns. Sub-basin OS2 Sub-basin OS2 is 0.96 acres and consists of a portion of Redman Drive and offsite landscape area. Runoff within this sub-basin will surface flow to proposed curb and gutter adjacent to the Site and enter the existing drainage ditch on the north side of Redman Drive at the western limits of the project. Water quality treatment nor detention will be provided for this sub-basin on the proposed site. Additionally, this basin is not included as a part of the total Site improvement area, as proposed off-site improvements will improve existing conditions and maintain historic drainage patterns. Sub-basin OS3 Sub-basin OS3 is a total of 0.45 acres, split into 3 sub-basins, each contributing to a proposed 2-foot wide curb cut. The improvements in this sub-basin include widening the Frontage Road approximately 10-feet to the west and adding curb and gutter. Historic drainage patterns of roadway runoff flowing to existing grass swales and 12” CMP culverts will be maintained. The Street Capacity section of this report includes a detailed description of flows in the roadway. Water quality treatment nor detention will be provided for this sub-basin on the proposed site. Additionally, this basin is not included as a part of the total Site improvement area, as proposed off-site improvements will improve existing conditions and maintain historic drainage patterns. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 9 Table 2. Summary of proposed drainage sub-basins. Basin ID Total Tributary Area (acres) Impervious Area (acres)1 Imperviousness 2-Year Peak Flow (CFS) 100-Year Peak Flow (CFS) A 5.39 3.65 64% 7.95 41.06 B1 1.72 1.52 89% 4.20 17.08 B2 1.27 1.13 90% 2.93 11.79 C 3.63 2.55 66% 6.20 32.11 D1 0.16 0.04 27% 0.12 0.54 D2 0.14 0.02 19% 0.09 0.37 O1 0.52 0.00 2% 0.22 0.97 O2 0.07 0.03 44% 0.10 0.45 O3 0.03 0.02 55% 0.05 0.22 O4 0.14 0.00 2% 0.06 0.26 Total On-Site2 13.07 8.96 66%21.91 104.86 Total On-Site to Detention3 12.31 8.92 70%21.48 102.95 Total On-Site to Offsite4 0.76 0.05 7.9%0.43 1.90 OS-1 0.91 0.83 91% 2.28 9.05 OS-2 0.96 0.55 58% 1.46 7.21 OS-3A 0.23 0.23 100% 0.58 2.14 OS-3B 0.13 0.13 100% 0.31 1.13 OS-2C 0.09 0.09 100% 0.20 0.74 Total Off-Site5 2.32 1.82 75%4.83 20.28 1. Includes pavement and roof areas. 2. Does not include O1 – O5 3. Includes A, B, C, and D 4. Includes O1 – O5 5.Includes OS1, OS2, and OS3 Final Drainage Report Mulberry Connection – Fort Collins, Colorado 10 Rain Garden A Rain Garden A is proposed to treat runoff from, sub-basin A. Unconcentrated sheet flow runoff will surface flow from the parking lot, down the rain garden slope (maximum 4:1) and into a sediment forebay proposed along the length of the bottom of the rain garden. Rain Garden A is designed with an 8-foot width bottom and 4:1 side slopes to the berm between the rain garden and detention pond. An underdrain is proposed along the length of the rain garden. The northern underdrain will discharge directly to the proposed dry well within the inflow infiltration basin. The southern underdrain will connect to the underdrain from the ADS system that discharges directly into the drywell. Two CDOT Type D inlets will convey flows greater than the WQCV to the detention pond. Inlet calculations for these inlets indicate that water will pond 0.39 feet above the WQCV surface in order for the inlets to convey the 100-year storm event. An equalizer pipe is proposed between the north and south portions of the rain garden to ensure the full volume is utilized. Final design details of the rain garden are provided in the Construction Documents and summarized in Table 3 below. Table 3. Rain Garden A design data. Calculated WQCV 4,702 cubic feet Required Flat Surface Area 3,005 square feet Provided Flat Surface Area 3,030 square feet Provided Volume 4,702 cubic feet Top of Media Elevation 4952.00 WQCV Ponding Depth 12 inches WQCV Ponding Elevation (Rim of Inlets) 4953.00 100-Year Ponding Depth 0.39 feet Top of Berm (between rain garden and pond) 4953.50 Maintenance: Maintenance access of Rain Garden A is provided via the adjacent parking lot along the east side of the rain garden. Several cleanouts are provided for the underdrains. A drainage easement has been provided around the Rain Garden. Overflow: In the case in which the Rain Garden becomes clogged and ponds to the top of berm height of 4953.50, water will spill over the berm west into the detention pond. Underground Facility An ADS SC-740 underground chamber system is proposed to treat the WQCV from sub-basin B. Runoff from sub-basin B will be collected by two double CDOT Type 13 inlets. These inlets connect to the ADS Inflow Manhole. The “low-flow” outlet pipe at the bottom of the manhole will convey the WQCV to the underground facility. Flows greater than the WQCV will pond within the manhole structure to the maximum elevation of WQCV storage in the underground facility and then enter the 24” outlet pipe, conveying flows to the detention pond. The underground facility has been designed per ADS recommendations, including an underdrain. The underdrain will outfall to the proposed dry well within the inflow infiltration basin Final Drainage Report Mulberry Connection – Fort Collins, Colorado 11 proposed within the detention pond. The ADS detail sheets and detail of the ADS Inflow Manhole are included in the Construction Documents. Table 4 below summarizes the ADS system design. Table 4. Summary of ADS system design. Required WQCV 4,096 cubic feet Number of Chambers 55 Bottom of Stone/Invert of Underdrain 4943.51 feet Ponding Depth within System 36 inches Invert of 100-year Pipe in “ADS Inflow Manhole” 4947.59 feet Maintenance: Maintenance access of the underground facility will be provided by access ports at one end of each of the chamber rows, per manufacturer recommendations. A drainage easement has been provided around the underground facility. Overflow: In the case in which the underground facility becomes plugged, water will pond within the storm sewer system, surcharging the inlets within the loading court and ponding within this area. Water will pond to an elevation of 4952.2 (3.9 feet below FFE of 4956.10) within the loading court before overtopping the highpoint in the access drive and flowing into Redman Drive. Rain Garden C Rain Garden C is proposed to treat the WQCV from sub-basin C. Unconcentrated sheet flow runoff will surface flow off the parking lot and down the rain garden slope (maximum 4:1) to a sediment forebay proposed along the length of the bottom of the Rain Garden. Rain Garden C is designed with maximum 4:1 side slopes to the berm between the rain garden and I-25 Frontage Road. An underdrain is proposed along the length of the rain garden. The underdrain will connect to the overflow inlet. A proposed CDOT Type D inlet will convey flows greater than the WQCV to the proposed storm system and ultimately the detention pond. Inlet calculations indicate that water will pond 0.6 feet in order to capture the 100-year flow rate in the Type D inlet. Final design details of the rain garden are provided in the Construction Documents and summarized in Table 5 below. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 12 Table 5. Rain Garden C design data. Calculated WQCV 3,264 cubic feet Required Flat Surface Area 2,087 square feet Provided Flat Surface Area 5,731 square feet Provided Volume 7581 cubic feet Top of Media Elevation 4952.00 WQCV Ponding Depth 12 inches WQCV Ponding Elevation (Rim of Inlets) 4953.00 100-Year Ponding Depth 0.60 feet Top of Berm (between rain garden and ROW) 4957.00 Maintenance: Maintenance access of Rain Garden C is provided via the adjacent parking lot along the west side of the rain garden. Two cleanouts are provided for the underdrain. A drainage easement has been provided around the Rain Garden. Overflow: In the case in which the outlet inlet become clogged water will pond within the Rain Garden to an elevation of 4953.70 (2.4 feet below FFE) before spilling over the sidewalk at the south side of the Rain Garden and flowing south into Redman Drive and the I-25 Frontage Road. Detention Pond A detention pond is proposed to detain site flows from the 100-year storm event to the 2-year historic release rate. Due to Site constraints, the inflow pipe to the pond is proposed with an “inflow infiltration basin”. The bottom elevation of the inflow basin will be approximately 4.5-feet below the bottom of the pond. In addition to the “inflow infiltration basin” being sized to drain it’s volume in 40 hours via infiltration, and 36” diameter dry well is proposed within the “inflow infiltration basin”. Table 6 summarizes the pond bottom elevation, “inflow infiltration basin” elevation, dry well elevations, and groundwater elevation in the approximate location of the pond (boring B-17) as shown in the Draft Geotechnical Evaluation prepared by Ninyo & Moore, dated July 2, 2019, included in Appendix E for reference. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 13 Table 6. Comparison of pond elevations and groundwater elevation. Finished Floor Elevation 4956.10 Pond Crest of Spillway Elevation 4952.00 100-Year Water Surface Elevation 4952.00 Pond Bottom Elevation at Outlet Structure 4949.00 “Inflow Infiltration Basin” Bottom Elevation 4944.50 “Inflow Infiltration Basin” Flat Bottom Area 353 FT 2 Depth of Infiltration Rock 2-FT Percolation Rate of Native Soil 30 min/in (2 in/hr) “Inflow Infiltration Basin” Volume 5,082 FT 3 Top of Gravel in Dry Well 4943.50 Invert of Underdrains into Dry Well 4943.00 Top of Perforated Dry Well Pipe 4942.50 Approximate Groundwater Elevation 4942.00 1 Bottom of Dry Well Structure 4941.00 Elevation of SW Soil in Boring B-17 4938.00 Bottom of Perforated Dry Well Pipe 4936.00 1. Existing ground elevation at approximate location of boring B-17 is 4951.00. Groundwater was encountered approximately 8-feet below existing ground surface. The elevation of the bottom of the pond is set to allow positive drainage from the pond outlet to the existing drainage ditch adjacent to the Site. The inflow infiltration basin has a total volume of 0.12 ac-ft (5,082 cubic feet). The percolation rate, as measured by Ninyo & Moore in October 2019, within the detention pond area is 30 mins/inch (2 in/hr). The flat area of the basin is 353 square feet, therefore, a basin volume of 2,353 cubic feet would be required to drain that surface area within 40 hours. As designed, the inflow infiltration basin has a total volume of 5,082 cubic feet, which provides an extra volume of 2,729 cubic feet above the required volume to infiltrate the surface area in 40 hours. The volume of the inflow infiltration basin is not included in the total detention pond volume calculations. Flows greater than the volume of the inflow infiltration basin will overtop the basin at the outflow trickle channel and enter the detention pond, discharging via the outlet structure. The 2-foot wide concrete V trickle channel conveys flows at 0.5% slope from the inflow infiltration basin to the outlet structure. One concrete forebay is proposed where the Rain Garden A 100-year flow enters the pond. A concrete V trickle channel Final Drainage Report Mulberry Connection – Fort Collins, Colorado 14 conveys these flows to the inflow infiltration basin. The detention pond also includes a maintenance path the length of the pond. A modified CDOT Type D inlet is proposed to serve as the outlet structure for the detention pond. The trickle channel is proposed to flow up to the base of the inlet. A 0.5-foot wide by 0.9-foot high square orifice is proposed at the trickle channel flowline/bottom of structure on the outside face of the structure. A trash rack is proposed over the orifice plate. The orifice is sized to release 3.40 CFS, which is the required 100- year release rate. The top of the inlet is set at an elevation of 4951.00, which is below the crest of the spillway, allowing any ponded water into the inlet. A restrictor plate over the outlet pipe (15-inch RCP) with the same open area (0.45 square feet) as the rectangular orifice is required to ensure the 100-year release rate is met. The crest of the emergency overflow spillway is set at the 100-year water surface elevation and 1.5-foot below the top of berm elevation. Spillway calculations provided in Appendix D indicate that the undetained 100-year flow rate flowing over the spillway will pond 0.5 feet above the crest. Maintenance of the detention pond is provided via a 12-foot gravel maintenance path accessible north of the pond via mountable curb in the parking lot. A 10-foot grass maintenance path along the bottom of the pond to allows access to the inflow infiltration basin and outlet structure. A drainage easement has been provided around the detention pond. Table 7. Detention Pond Summary Table Approx. Bottom of Pond Elevation 4949.00 100-Year Orifice Open Area 0.45 SF Top of Outlet Structure 4951.00 100-Year Water Surface Elevation 4952.00 Crest of Spillway Elevation 4952.00 Top of Berm Elevation 4953.50 Storm Sewer Conveyance Storm sewer pipe is proposed to connect sub-basins A, B, C, and D to the detention pond. The main stormline (rain garden C to detention pond) has been designed so that there is minimal ponding in the 100- year storm event. The tailwater condition into the pond was set at an elevation of 4949.66, which is the maximum ponding elevation with the inflow infiltration basin. This tailwater elevation causes minimal surcharging to occur at the Rain Garden C inlet and Inlet D4, just downstream of Rain Garden C in the 100- year storm event. Ponded water within Rain Garden C will pond to an elevation of 4953.70 (2.4 feet below FFE) before overtopping the south sidewalk and flowing into Redman Drive and the I-25 Frontage Road. A ponding depth above the inlet rim of 0.60 feet will occur. Ponded water at Inlet D4 will pond to an elevation of 4955.42 (0.68 feet below FFE) before spilling over the berm at the southern property line and flow into Redman Drive. A ponding depth of 2.42 feet above the rim of the inlet will occur before the berm if overtopped. Due to the required elevations within the loading dock area, ponding will occur within this area during the 100-year storm event. In addition to the HGL surcharging at all these locations, when the detention pond is Final Drainage Report Mulberry Connection – Fort Collins, Colorado 15 at the 100-year water surface elevation (4952.00), the water surface will equalize into this area. The maximum ponding depth in this area is 12-inches. Because of this ponding in the 100-year storm event, only the 2-year storm event was modeled for the length of pipe within the truck court. Inlet Capacity The capacity of each proposed inlet was evaluated to determine the maximum ponding depth to convey the 100-year storm event. The results of the capacity analysis indicate that the CDOT Type D inlets have the capacity to collect contributing runoff with minimal ponding during the 100-year storm event. Street Capacity Two streets within the project limits were evaluated, private Redman Drive and public I-25 Frontage Road. I-25 Frontage Road North of Redman Drive The I-25 Frontage Road is a public roadway owned and maintained by CDOT. The below typical section shows the ultimate cross-section of the roadway. As shown in the figure above, the proposed condition north of Redman Drive will maintain the existing super-elevated condition of the roadway, with runoff flowing east to west across the roadway. Sub-Basin OS-1 was delineated to capture the entire portion of the I-25 Frontage Road adjacent to the on-site improvements. Approximately 2.3 CFS and 9.3 CFS of runoff is generated from sub-basins OS-1 and OS4 in the 2-year and 100-year storm events, respectively. The UD-Inlet street capacity analysis indicates that in the 2-year storm event flows will spread 14.6 feet from the flowline into the roadway, which will occupy 8.5-feet into the travel lane. This spread results in 3.5-inches of ponding at the curb flowline. In the 100- year storm event flows will spread 18-feet from the flowline into the roadway, which will occupy the travel lane and 1-foot into the turn lane. This spread results in 5.1-inches of ponding at the curb flowline. Street capacity calculations are included in Appendix D. These flows along the frontage of the site will be routed east down Redman Drive. I-25 Frontage Road South of Redman Drive Final Drainage Report Mulberry Connection – Fort Collins, Colorado 16 The I-25 Frontage Road will also be widened along the southern adjacent property. In the existing condition, runoff from the roadway surface flows west into existing swales and 12” CMP culverts. The existing condition does not have curb and gutter along this portion of the 1-25 Frontage Road. The proposed condition includes widening of the roadway approximately 10 feet and adding curb and gutter. Curb cuts have been added along the proposed curb and gutter to allow runoff to enter the existing swale. Proposed grading will protect the existing culverts in place. Table 8 lists the existing and proposed imperviousness and flow rates for the 3 sub-basins encompassing these improvements. Table 8. Existing and Proposed Conditions along Southern I-25 Frontage Road Improvements. Sub-Basin Area (AC) Imperviousness 2-Year Flow Rate (CFS) 100-Year Flow Rate (CFS) EX4A 0.23 73% 0.45 1.94 OS3A 100% 0.58 2.14 Change -- +27% +0.13 +0.20 EX4B 0.13 86% 0.27 1.13 OS3B 100% 0.31 1.13 Change -- +14% +0.04 0.00 EX4C 0.09 96% 0.20 0.74 OS3C 100% 0.20 0.74 Change -- +4% 0.00 0.00 As shown in Table 8 above, the flows in both storm events for all basins increase less than 1 CFS in the proposed condition. Therefore, negative impacts to downstream stormwater infrastructure are not anticipated. Additionally, street capacity calculations have been completed for this portion of the I-25 Frontage Road. The total accumulated flows at the south side of the improvements are 1.0 CFS and 3.7 CFS in the 2-year and 100-year storm events, respectively. The UD-Inlet analysis indicates that in the 2- year storm event flows will spread 12.5 feet with a ponding at the gutter flowline of 3 inches. In the 100- year storm event flows will spread 15.2 feet with a ponding at the gutter flowline of 3.7 inches. This is the worst case scenario, assuming all flows from sub-basin OS3 are conveyed in the curb and gutter, which in the proposed condition, the majority of flows will be conveyed in the existing swales and culverts. Redman Drive Redman Drive is an existing private street with a total width of 40 feet and a crown approximately 20-ft from the proposed northern curb line. Redman Drive currently has no curb and gutter, with an existing swale on the north side conveying runoff west to Cooper Slough. Curb and gutter and driveway valley gutters are proposed along the north property frontage. Flows from I-25 Frontage Road (sub-basins O4 and OS1), Redman Drive (sub-basin OS-2) and a small portion of on-site runoff (sub-basins O2 and O3) will be conveyed west via the proposed curb and gutter until the curb is transitioned back to the existing roadside swale. The total flows to the north curb and gutter along Redman Drive at the downstream design point are 3.67 CFS and 16.09 CFS in the 2-year and 100-year storm events, respectively. The street capacity was evaluated using the MHFD UD-Inlet spreadsheet. The results of the analysis indicate that water will spread Final Drainage Report Mulberry Connection Fort Collins, Colorado 17 21.7-feet into Redman Drive in the 2-year storm event, with 5.2-inches of ponding at the curb flowline. In the 100-year storm event the north side of the street will not have capacity to convey the entire 100-year flows, therefore, the runoff will overtop the crown and utilize both sides of the street. A ponding depth of 8.1-inches at the curb flowline will result in a spread of 33.8 feet. Street capacity calculations are included in Appendix D. Flows that overtop the crown will flow south into the existing swale and culverts along the south side of the road. In the 100-year storm event, flows from the north side of the road will combine with flows from the south side of the road. This combined runoff will flow into the existing swales, which have depths between 3 and 5 feet. Runoff will continue to flow south through the exis beneath the southern driveways. These culverts do not have capacity to convey all the proposed 100-year flows, therefore, water will pond in the swales and then overtop into the roadway, continuing to flow west, bypassing the culverts. All flows in Redman Drive will flow west into Cooper Slough. VARIANCE REQUESTS A variance is requested to allow the inflow infiltration basin within the detention pond. Variance has been approved by Fort Collins Stormwater Division. Please see Appendix F for approved Variance. EROSION CONTROL A separate Erosion Control Report will be provided in addition to this Final Drainage Report. CONCLUSIONS COMPLIANCE WITH STANDARDS The Mulberry Connection project is in compliance with City of Fort Collins criteria for storm drainage design. Stormwater Crite and the Urban Drainage Flood Control District Urban Storm Drainage Criteria Manual Volumes 1, 2, and 3 have been utilized for reference. SUMMARY OF CONCEPT The proposed drainage concept is to surface flow runoff from impervious areas to pervious area to the extent practicable. Two rain gardens and one underground facility are proposed to treat the WQCV from as much of the Site as possible. A detention pond is proposed to detain the on-site 100-year runoff volume to the 2-year historic on-site flow. Downstream impacts due to the development of this Site are not anticipated. REFERENCES Fort Collins Stormwater Criteria Manual, December 2018 Edition, City of Fort Collins. Urban Storm Drainage Criteria Manual, Volume 1-3, Mile High Flood District, Denver, CO; January 2016, with latest revisions. Final Drainage Report Mulberry Connection – Fort Collins, Colorado 18 APPENDICES A. NRCS Data and FEMA Map B. Existing and Proposed Drainage Map C. Hydrologic Calculations D. Hydraulic Calculations E. Reference Materials F. Approved Stormwater Alternative Compliance / Variance 17 APPENDIX A 18 APPENDIX B 19 APPENDIX C DESIGN POINT DESIGN BASIN AREA (AC) RUNOFF COEFF C2 tc(min) C*A(ac) I (in/hr) Q (cfs) tc(max) S(C*A) (ac) I (in/hr) Q (cfs) SLOPE (%) STREET FLOW(cfs DESIGN FLOW(cfs ) SLOPE (%) PIPE SIZE (in) LENGTH (ft) VELOCIT Y tt (min) STORM LINE DESIGN POINT DESIGN BASIN AREA (AC) RUNOFF COEFF C100 tc(min) C*A(ac) I (in/hr) Q (cfs) tc(max) S(C*A) (ac) I (in/hr) Q (cfs) SLOPE (%) STREET FLOW(cfs) DESIGN FLOW(cfs) SLOPE (%) PIPE SIZE (in) LENGTH (ft) VELOCITY (fps) tt (min) STORM LINE PROJECT NAME: POUDRE VALLEY DEVELOPMENT DATE: 1/18/2021 PROJECT NUMBER: 096635000 CALCULATED BY: HMO CHECKED BY: DLS TOTAL IMPERVIOUS AREA IMPERVIOUS AREA TREATED (AC) (AC) Q2 Q100 EX1 EX1 13.23 0.00 0.00 4.07 17.17 EX2 EX2 0.55 0.00 0.00 0.56 2.55 EX3 EX3 0.91 0.00 0.00 1.06 4.78 EX4A EX4A 0.23 0.00 0.00 0.45 1.94 EX4B EX4B 0.13 0.00 0.00 0.27 1.13 EX4C EX4C 0.09 0.00 0.00 0.20 0.74 15.14 0.00 0.00 6.60 28.31 A A 5.39 3.65 3.65 7.95 41.06 B1 B1 1.72 1.52 1.52 4.20 17.08 B2 B2 1.27 1.13 1.13 2.93 11.79 C C 3.63 2.55 2.55 6.20 32.11 D1 D1 0.16 0.04 0.04 0.12 0.54 D2 D2 0.14 0.02 0.02 0.09 0.37 O1 O1 0.52 0.00 0.00 0.22 0.97 O2 O2 0.07 0.03 0.00 0.10 0.45 O3 O3 0.03 0.02 0.00 0.05 0.22 O4 O4 0.14 0.00 0.00 0.06 0.26 13.07 8.96 -- 21.91 104.86 12.01 8.85 8.85 -- -- 0.30 0.06 0.06 -- -- 12.31 8.92 --21.48 102.95 OS1 OS1 0.91 0.83 0.00 2.28 9.05 OS2 OS2 0.96 0.55 0.00 1.46 7.21 OS3A OS3A 0.23 0.23 0.00 0.58 2.14 OS3B OS3B 0.13 0.13 0.00 0.31 1.13 OS3C OS3C 0.09 0.09 0.00 0.20 0.74 2.32 1.82 0.00 4.83 20.28 ON-SITE BASINS OFF-SITE BASINS TOTAL TOTAL TOTAL TOTAL ON-SITE TO DETENTION TOTAL ON-SITE TO WQ TREATMENT (LID) TOTAL ON-SITE TO WQ TREATMENT (POND) EXISTING BASINS DESIGN POINT RATIONAL CALCULATIONS SUMMARY TRIBUTARY BASINS TRIBUTARY AREA (AC) PEAK FLOWS (CFS) 20 APPENDIX D Ac t i v e S c e n a r i o : 2 - Y R Fl e x T a b l e : C a t c h B a s i n T a b l e Mu l b e r r y C o n n e c t i o n Fl o w ( T o t a l O u t ) (c f s ) He a d l o s s (f t ) Hy d r a u l i c G r a d e Li n e ( O u t ) (f t ) Hy d r a u l i c G r a d e Li n e ( I n ) (f t ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n ( R i m ) (f t ) La b e l 6. 2 8 0. 1 4 4, 9 5 0 . 0 9 4, 9 5 0 . 2 3 4, 9 4 9 . 3 0 4, 9 5 3 . 0 0 RA I N G A R D E N C OU T L E T S T R U C T U R E 5. 8 3 0. 1 3 4, 9 4 9 . 1 7 4, 9 4 9 . 3 0 4, 9 4 8 . 4 1 4, 9 5 3 . 2 5 IN L E T D 4 6. 8 7 0. 3 9 4, 9 4 9 . 1 7 4, 9 4 9 . 5 6 4, 9 4 7 . 7 5 4, 9 5 0 . 9 7 IN L E T B 2 5. 1 7 0. 1 4 4, 9 5 1 . 1 0 4, 9 5 1 . 2 4 4, 9 4 8 . 9 5 4, 9 5 1 . 8 8 IN L E T B 1 11 . 1 6 0. 1 9 4, 9 4 7 . 1 5 4, 9 4 7 . 3 5 4, 9 4 6 . 1 0 4, 9 5 3 . 7 7 IN L E T D 1 3. 4 0 0. 0 0 4, 9 4 9 . 7 6 4, 9 4 9 . 7 6 4, 9 4 9 . 0 0 4, 9 5 1 . 0 0 DE T E N T I O N P O N D OU T L E T S T U C T U R E 41 . 0 6 0. 5 5 4, 9 5 2 . 1 1 4, 9 5 2 . 6 6 4, 9 4 9 . 6 7 4, 9 5 3 . 0 0 RG A O U T L E T Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Fl e x T a b l e : C a t c h m e n t T a b l e Mu l b e r r y C o n n e c t i o n Fl o w ( T o t a l O u t ) (c f s ) Ou t f l o w E l e m e n t La b e l 5. 1 7 IN L E T B 1 CM - B 1 2. 0 4 IN L E T B 2 CM - B 2 6. 2 8 RA I N G A R D E N C OU T L E T ST R U C T U R E CM - C 0. 0 9 IN L E T D 4 CM - D 2 0. 1 1 IN L E T D 1 CM - D 1 Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Fl e x T a b l e : C o n d u i t T a b l e Mu l b e r r y C o n n e c t i o n Hy d r a u l i c Gr a d e L i n e (O u t ) (f t ) Hy d r a u l i c Gr a d e L i n e (I n ) (f t ) Ca p a c i t y (F u l l Fl o w ) (c f s ) Ve l o c i t y (f t / s ) Fl o w (c f s ) Ma n n i n g ' s n Di a m e t e r (i n ) Sl o p e (C a l c u l a t ed ) (f t / f t ) Le n g t h (U s e r De f i n e d ) (f t ) In v e r t (S t o p ) (f t ) St o p N o d e In v e r t (S t a r t ) (f t ) St a r t N o d e La b e l 4, 9 4 5 . 4 9 4, 9 4 6 . 4 9 47 . 0 5 5. 4 3 10 . 9 9 0. 0 1 3 36 . 0 0. 0 0 5 18 8 . 9 4, 9 4 4 . 5 0 PO N D IN F L O W FE S 4, 9 4 5 . 4 4 MH - 1 PI P E - 0 5 4, 9 4 6 . 7 2 4, 9 4 7 . 1 5 47 . 3 4 5. 4 7 11 . 1 6 0. 0 1 3 36 . 0 0. 0 0 5 13 0 . 2 4, 9 4 5 . 4 4 MH - 1 4, 9 4 6 . 1 0 IN L E T D 1 PI P E - 1 7 (1 ) 4, 9 4 7 . 3 5 4, 9 4 7 . 9 5 47 . 1 5 5. 4 7 11 . 2 6 0. 0 1 3 36 . 0 0. 0 0 5 15 8 . 9 4, 9 4 6 . 1 0 IN L E T D 1 4, 9 4 6 . 8 9 MH - D 2 PI P E - 1 7 4, 9 4 9 . 3 0 4, 9 5 0 . 0 9 47 . 2 8 4. 6 4 6. 2 8 0. 0 1 3 36 . 0 0. 0 0 5 17 7 . 1 4, 9 4 8 . 4 1 IN L E T D 4 4, 9 4 9 . 3 0 RA I N GA R D E N C OU T L E T ST R U C T U R E PI P E - 0 8 4, 9 4 8 . 2 3 4, 9 4 8 . 5 2 16 . 0 0 4. 8 9 6. 8 3 0. 0 1 3 24 . 0 0. 0 0 5 14 0 . 4 4, 9 4 6 . 8 9 MH - D 2 4, 9 4 7 . 5 9 AD S I N L E T MH PI P E - 2 7 4, 9 4 9 . 5 2 4, 9 4 9 . 7 6 4. 9 1 4. 3 2 3. 4 0 0. 0 1 3 15 . 0 0. 0 0 6 38 . 0 4, 9 4 8 . 7 8 PO N D OU T F A L L FE S 4, 9 4 9 . 0 0 DE T E N T I O N PO N D OU T L E T ST U C T U R E PI P E - 0 4 4, 9 4 9 . 5 6 4, 9 5 1 . 1 0 4. 5 8 4. 2 2 5. 1 7 0. 0 1 3 15 . 0 0. 0 0 5 23 9 . 0 4, 9 4 7 . 7 5 IN L E T B 2 4, 9 4 8 . 9 5 IN L E T B 1 PI P E - 3 1 4, 9 4 8 . 8 0 4, 9 4 9 . 1 7 4. 5 4 5. 6 0 6. 8 7 0. 0 1 3 15 . 0 0. 0 0 5 32 . 4 4, 9 4 7 . 5 9 AD S I N L E T MH 4, 9 4 7 . 7 5 IN L E T B 2 PI P E - 3 0 4, 9 4 8 . 2 3 4, 9 4 9 . 1 7 49 . 1 0 4. 6 7 5. 8 3 0. 0 1 3 36 . 0 0. 0 0 5 20 3 . 0 4, 9 4 7 . 3 1 MH - D 2 4, 9 4 8 . 4 1 IN L E T D 4 PI P E - 0 9 4, 9 5 1 . 7 0 4, 9 5 2 . 1 1 29 . 0 0 8. 3 6 41 . 0 6 0. 0 1 3 30 . 0 0. 0 0 5 24 . 0 4, 9 4 9 . 5 5 RG P O N D IN F L O W 4, 9 4 9 . 6 7 RG A OU T L E T CO - 3 Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Fl e x T a b l e : M a n h o l e T a b l e Mu l b e r r y C o n n e c t i o n He a d l o s s (f t ) Hy d r a u l i c G r a d e Li n e ( I n ) (f t ) Hy d r a u l i c G r a d e Li n e ( O u t ) (f t ) Fl o w ( T o t a l O u t ) (c f s ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n ( R i m ) (f t ) La b e l 0. 2 3 4, 9 4 6 . 7 2 4, 9 4 6 . 4 9 10 . 9 9 4, 9 4 5 . 4 4 4, 9 5 3 . 8 8 MH - 1 0. 2 9 4, 9 4 8 . 8 0 4, 9 4 8 . 5 2 6. 8 3 4, 9 4 7 . 5 9 4, 9 5 1 . 3 6 AD S I N L E T M H 0. 2 7 4, 9 4 8 . 2 3 4, 9 4 7 . 9 5 11 . 2 6 4, 9 4 6 . 8 9 4, 9 5 3 . 4 2 MH - D 2 Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Fl e x T a b l e : O u t f a l l T a b l e Mu l b e r r y C o n n e c t i o n Sy s t e m R a t i o n a l Fl o w (c f s ) Sy s t e m Ad d i t i o n a l F l o w (c f s ) Bo u n d a r y C o n d i t i o n T y p e Hy d r a u l i c G r a d e (f t ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n (G r o u n d ) (f t ) La b e l 0. 0 0 3. 4 0 Fr e e O u t f a l l 4, 9 4 9 . 5 2 4, 9 4 8 . 7 8 4, 9 4 8 . 7 8 PO N D O U T F A L L FE S 10 . 7 7 0. 0 0 Fr e e O u t f a l l 4, 9 4 5 . 4 9 4, 9 4 4 . 5 0 4, 9 4 8 . 3 3 PO N D I N F L O W FE S 0. 0 0 41 . 0 6 Fr e e O u t f a l l 4, 9 5 1 . 7 0 4, 9 4 9 . 5 5 4, 9 4 9 . 5 5 RG P O N D IN F L O W Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 9 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Pr o f i l e R e p o r t En g i n e e r i n g P r o f i l e - M a i n l i n e ( M u l b e r r y . s t s w ) Mu l b e r r y C o n n e c t i o n Elevation(ft) Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Fl e x T a b l e : O u t f a l l T a b l e Mu l b e r r y C o n n e c t i o n Sy s t e m R a t i o n a l Fl o w (c f s ) Sy s t e m Ad d i t i o n a l F l o w (c f s ) Bo u n d a r y C o n d i t i o n T y p e Hy d r a u l i c G r a d e (f t ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n (G r o u n d ) (f t ) La b e l 0. 0 0 3. 4 0 Fr e e O u t f a l l 4, 9 4 9 . 5 2 4, 9 4 8 . 7 8 4, 9 4 8 . 7 8 PO N D O U T F A L L FE S 10 . 7 7 0. 0 0 Fr e e O u t f a l l 4, 9 4 5 . 4 9 4, 9 4 4 . 5 0 4, 9 4 8 . 3 3 PO N D I N F L O W FE S 0. 0 0 41 . 0 6 Fr e e O u t f a l l 4, 9 5 1 . 7 0 4, 9 4 9 . 5 5 4, 9 4 9 . 5 5 RG P O N D IN F L O W Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 2 - Y R Pr o f i l e R e p o r t En g i n e e r i n g P r o f i l e - T r u c k c o u r t t o M a i n l i n e ( M u l b e r r y . s t s w ) Mu l b e r r y C o n n e c t i o n Elevation(ft) Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Fl e x T a b l e : C a t c h B a s i n T a b l e Mu l b e r r y C o n n e c t i o n Fl o w ( T o t a l O u t ) (c f s ) He a d l o s s (f t ) Hy d r a u l i c G r a d e Li n e ( O u t ) (f t ) Hy d r a u l i c G r a d e Li n e ( I n ) (f t ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n ( R i m ) (f t ) La b e l 32 . 4 0 0. 1 6 4, 9 5 3 . 0 0 4, 9 5 3 . 1 6 4, 9 4 9 . 3 0 4, 9 5 3 . 0 0 RA I N G A R D E N C OU T L E T S T R U C T U R E 25 . 1 4 0. 1 0 4, 9 5 3 . 2 5 4, 9 5 3 . 3 5 4, 9 4 8 . 4 1 4, 9 5 3 . 2 5 IN L E T D 4 28 . 0 6 6. 5 0 4, 9 5 0 . 9 7 4, 9 5 7 . 4 7 4, 9 4 7 . 7 5 4, 9 5 0 . 9 7 IN L E T B 2 17 . 2 5 1. 5 4 4, 9 5 1 . 8 8 4, 9 5 3 . 4 2 4, 9 4 8 . 9 5 4, 9 5 1 . 8 8 IN L E T B 1 46 . 1 7 0. 3 3 4, 9 5 1 . 5 6 4, 9 5 1 . 8 9 4, 9 4 6 . 1 0 4, 9 5 3 . 7 7 IN L E T D 1 3. 4 0 0. 0 0 4, 9 4 9 . 7 6 4, 9 4 9 . 7 6 4, 9 4 9 . 0 0 4, 9 5 1 . 0 0 DE T E N T I O N P O N D OU T L E T S T U C T U R E 41 . 0 6 0. 5 4 4, 9 5 2 . 2 4 4, 9 5 2 . 7 9 4, 9 4 9 . 6 7 4, 9 5 3 . 0 0 RG A O U T L E T Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Fl e x T a b l e : C a t c h m e n t T a b l e Mu l b e r r y C o n n e c t i o n Fl o w ( T o t a l O u t ) (c f s ) Ou t f l o w E l e m e n t La b e l 17 . 2 5 IN L E T B 1 CM - B 1 11 . 9 2 IN L E T B 2 CM - B 2 32 . 4 0 RA I N G A R D E N C OU T L E T ST R U C T U R E CM - C 0. 3 9 IN L E T D 4 CM - D 2 0. 5 4 IN L E T D 1 CM - D 1 Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Fl e x T a b l e : C o n d u i t T a b l e Mu l b e r r y C o n n e c t i o n Hy d r a u l i c Gr a d e L i n e (O u t ) (f t ) Hy d r a u l i c Gr a d e L i n e (I n ) (f t ) Ca p a c i t y (F u l l Fl o w ) (c f s ) Ve l o c i t y (f t / s ) Fl o w (c f s ) Ma n n i n g ' s n Di a m e t e r (i n ) Sl o p e (C a l c u l a t ed ) (f t / f t ) Le n g t h (U s e r De f i n e d ) (f t ) In v e r t (S t o p ) (f t ) St o p N o d e In v e r t (S t a r t ) (f t ) St a r t N o d e La b e l 4, 9 4 9 . 6 6 4, 9 5 0 . 5 4 47 . 0 5 6. 4 6 45 . 6 3 0. 0 1 3 36 . 0 0. 0 0 5 18 8 . 9 4, 9 4 4 . 5 0 PO N D IN F L O W FE S 4, 9 4 5 . 4 4 MH - 1 PI P E - 0 5 4, 9 5 0 . 9 3 4, 9 5 1 . 5 6 47 . 3 4 6. 5 3 46 . 1 7 0. 0 1 3 36 . 0 0. 0 0 5 13 0 . 2 4, 9 4 5 . 4 4 MH - 1 4, 9 4 6 . 1 0 IN L E T D 1 PI P E - 1 7 (1 ) 4, 9 5 1 . 8 9 4, 9 5 2 . 6 6 47 . 1 5 6. 5 5 46 . 3 3 0. 0 1 3 36 . 0 0. 0 0 5 15 8 . 9 4, 9 4 6 . 1 0 IN L E T D 1 4, 9 4 6 . 8 9 MH - D 2 PI P E - 1 7 4, 9 5 3 . 2 5 4, 9 5 3 . 6 7 47 . 2 8 4. 5 8 32 . 4 0 0. 0 1 3 36 . 0 0. 0 0 5 17 7 . 1 4, 9 4 8 . 4 1 IN L E T D 4 4, 9 4 9 . 3 0 RA I N GA R D E N C OU T L E T ST R U C T U R E PI P E - 0 8 4, 9 5 3 . 1 2 4, 9 5 5 . 2 8 16 . 0 0 8. 9 2 28 . 0 2 0. 0 1 3 24 . 0 0. 0 0 5 14 0 . 4 4, 9 4 6 . 8 9 MH - D 2 4, 9 4 7 . 5 9 AD S I N L E T MH PI P E - 2 7 4, 9 4 9 . 5 2 4, 9 4 9 . 7 6 4. 9 1 4. 3 2 3. 4 0 0. 0 1 3 15 . 0 0. 0 0 6 38 . 0 4, 9 4 8 . 7 8 PO N D OU T F A L L FE S 4, 9 4 9 . 0 0 DE T E N T I O N PO N D OU T L E T ST U C T U R E PI P E - 0 4 4, 9 5 0 . 9 7 4, 9 6 8 . 0 2 4. 5 8 14 . 0 6 17 . 2 5 0. 0 1 3 15 . 0 0. 0 0 5 23 9 . 0 4, 9 4 7 . 7 5 IN L E T B 2 4, 9 4 8 . 9 5 IN L E T B 1 PI P E - 3 1 4, 9 5 1 . 3 6 4, 9 5 7 . 4 7 4. 5 4 22 . 8 7 28 . 0 6 0. 0 1 3 15 . 0 0. 0 0 5 32 . 4 4, 9 4 7 . 5 9 AD S I N L E T MH 4, 9 4 7 . 7 5 IN L E T B 2 PI P E - 3 0 4, 9 5 3 . 1 2 4, 9 5 3 . 4 1 49 . 1 0 3. 5 6 25 . 1 4 0. 0 1 3 36 . 0 0. 0 0 5 20 3 . 0 4, 9 4 7 . 3 1 MH - D 2 4, 9 4 8 . 4 1 IN L E T D 4 PI P E - 0 9 4, 9 5 2 . 0 0 4, 9 5 2 . 2 4 29 . 0 0 8. 3 6 41 . 0 6 0. 0 1 3 30 . 0 0. 0 0 5 24 . 0 4, 9 4 9 . 5 5 RG P O N D IN F L O W 4, 9 4 9 . 6 7 RG A OU T L E T CO - 3 Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Fl e x T a b l e : M a n h o l e T a b l e Mu l b e r r y C o n n e c t i o n He a d l o s s (f t ) Hy d r a u l i c G r a d e Li n e ( I n ) (f t ) Hy d r a u l i c G r a d e Li n e ( O u t ) (f t ) Fl o w ( T o t a l O u t ) (c f s ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n ( R i m ) (f t ) La b e l 0. 3 9 4, 9 5 0 . 9 3 4, 9 5 0 . 5 4 45 . 6 3 4, 9 4 5 . 4 4 4, 9 5 3 . 8 8 MH - 1 0. 9 9 4, 9 5 2 . 3 5 4, 9 5 1 . 3 6 28 . 0 2 4, 9 4 7 . 5 9 4, 9 5 1 . 3 6 AD S I N L E T M H 0. 4 7 4, 9 5 3 . 1 2 4, 9 5 2 . 6 6 46 . 3 3 4, 9 4 6 . 8 9 4, 9 5 3 . 4 2 MH - D 2 Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Fl e x T a b l e : O u t f a l l T a b l e Mu l b e r r y C o n n e c t i o n Sy s t e m R a t i o n a l Fl o w (c f s ) Sy s t e m Ad d i t i o n a l F l o w (c f s ) El e v a t i o n ( U s e r De f i n e d Ta i l w a t e r ) (f t ) Bo u n d a r y C o n d i t i o n T y p e Hy d r a u l i c G r a d e (f t ) El e v a t i o n (I n v e r t ) (f t ) El e v a t i o n (G r o u n d ) (f t ) La b e l 0. 0 0 3. 4 0 Fr e e O u t f a l l 4, 9 4 9 . 5 2 4, 9 4 8 . 7 8 4, 9 4 8 . 7 8 PO N D O U T F A L L FE S 44 . 8 9 0. 0 0 4, 9 4 9 . 6 6 Us e r D e f i n e d T a i l w a t e r 4, 9 4 9 . 6 6 4, 9 4 4 . 5 0 4, 9 4 8 . 3 3 PO N D I N F L O W FE S 0. 0 0 41 . 0 6 4, 9 5 2 . 0 0 Us e r D e f i n e d T a i l w a t e r 4, 9 5 2 . 0 0 4, 9 4 9 . 5 5 4, 9 4 9 . 5 5 RG P O N D IN F L O W Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Pr o f i l e R e p o r t En g i n e e r i n g P r o f i l e - M a i n l i n e ( M u l b e r r y . s t s w ) Mu l b e r r y C o n n e c t i o n Elevation (ft) Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Pr o f i l e R e p o r t En g i n e e r i n g P r o f i l e - O u t f a l l ( M u l b e r r y . s t s w ) Mu l b e r r y C o n n e c t i o n Elevation (ft) Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Ac t i v e S c e n a r i o : 1 0 0 - Y R Pr o f i l e R e p o r t En g i n e e r i n g P r o f i l e - R a i n G a r d e n A ( M u l b e r r y . s t s w ) Mu l b e r r y C o n n e c t i o n Elevation (ft) Pa g e 1 o f 1 27 S i e m o n C o m p a n y D r i v e S u i t e 2 0 0 W W a t e r t o w n , C T 0 6 7 9 5 U S A + 1 - 2 0 3 - 75 5 - 1 6 6 6 1/ 1 8 / 2 0 2 1 St o r m C A D [1 0 . 0 2 . 0 3 . 0 3 ] Be n t l e y S y s t e m s , I n c . H a e s t a d M e t h o d s S o l u t i o n C e n t e r Mu l b e r r y . s t s w Mulberry Connection Fort Collins, CO 1/19/2021 Rain Garden A CDOT Double Type D Close Mesh Grate 3.44' x 2.79'per grate Area of Grate (sq ft)19.1952 Apply 70% for Grate Open Area 13.44 100-Yr Flow, Q =41.06 cfs Area of Opening, A (Grate Area x Opening Ratio) = 13.44 sf Ponding, h = 0.39 ft Q = CA ( 2gh ) ^ 1/2 = 0.60 x A ( 2 x 32.2 ) ^ 1/2 x h ^1/2 Q = 67.34 x h ^ 1/2 For h = 0.39 Q intercepted, Qi = 42.05 cfs Q intercepted, Qi =42.05 > Q =41.06 cfs GRATE CALCULATIONS Pond Grate Description: Dimensions: Mulberry Connection Fort Collins, CO 1/19/2021 Rain Garden C CDOT Type D Close Mesh Grate 3.44' x 2.79' Area of Grate (sq ft)9.5976 Apply 70% for Grate Open Area 6.72 100-Yr Flow, Q =32.11 cfs Area of Opening, A (Grate Area x Opening Ratio) = 6.72 sf Ponding, h = 0.60 ft Q = CA ( 2gh ) ^ 1/2 = 0.60 x A ( 2 x 32.2 ) ^ 1/2 x h ^1/2 Q = 41.76 x h ^ 1/2 For h = 0.60 Q intercepted, Qi = 32.35 cfs Q intercepted, Qi =32.35 > Q =32.11 cfs GRATE CALCULATIONS Pond Grate Description: Dimensions: Mulberry Connection Fort Collins, CO 1/19/2021 Inlet D1 CDOT Type D Close Mesh Grate 3.44' x 2.79' Area of Grate (sq ft)9.5976 Apply 70% for Grate Open Area 6.72 100-Yr Flow, Q =0.54 cfs Area of Opening, A (Grate Area x Opening Ratio) = 6.72 sf Ponding, h = 0.02 ft Q = CA ( 2gh ) ^ 1/2 = 0.60 x A ( 2 x 32.2 ) ^ 1/2 x h ^1/2 Q = 7.62 x h ^ 1/2 For h = 0.02 Q intercepted, Qi = 1.08 cfs Q intercepted, Qi =1.08 > Q =0.54 cfs GRATE CALCULATIONS Pond Grate Description: Dimensions: Mulberry Connection Fort Collins, CO 1/19/2021 Inlet D4 CDOT Type D Close Mesh Grate 3.44' x 2.79' Area of Grate (sq ft)9.5976 Apply 70% for Grate Open Area 6.72 100-Yr Flow, Q =0.37 cfs Area of Opening, A (Grate Area x Opening Ratio) = 6.72 sf Ponding, h = 0.02 ft Q = CA ( 2gh ) ^ 1/2 = 0.60 x A ( 2 x 32.2 ) ^ 1/2 x h ^1/2 Q = 7.62 x h ^ 1/2 For h = 0.02 Q intercepted, Qi = 1.08 cfs Q intercepted, Qi =1.08 > Q =0.37 cfs GRATE CALCULATIONS Pond Grate Description: Dimensions: Mulberry Connection Fort Collins, CO 1/19/2021 Inlet B1 CDOT Type 13 Inlet 3.27' x 1.88' Area of Grate (sq ft)6.0912 Apply 70% for Grate Open Area 4.26 100-Yr Flow, Q =17.08 cfs Area of Opening, A (Grate Area x Opening Ratio) = 4.26 sf Ponding, h = 0.50 ft Q = CA ( 2gh ) ^ 1/2 = 0.60 x A ( 2 x 32.2 ) ^ 1/2 x h ^1/2 Q = 24.20 x h ^ 1/2 For h = 0.50 Q intercepted, Qi = 17.11 cfs Q intercepted, Qi =17.11 > Q =17.08 cfs GRATE CALCULATIONS Pond Grate Description: Dimensions: Mulberry Connection Fort Collins, CO 1/19/2021 Inlet B2 CDOT Type 13 Inlet 3.27' x 1.88' Area of Grate (sq ft)6.0912 Apply 70% for Grate Open Area 4.26 100-Yr Flow, Q =11.79 cfs Area of Opening, A (Grate Area x Opening Ratio) = 4.26 sf Ponding, h = 0.35 ft Q = CA ( 2gh ) ^ 1/2 = 0.60 x A ( 2 x 32.2 ) ^ 1/2 x h ^1/2 Q = 20.24 x h ^ 1/2 For h = 0.35 Q intercepted, Qi = 11.98 cfs Q intercepted, Qi =11.98 > Q =11.79 cfs GRATE CALCULATIONS Pond Grate Description: Dimensions: 4582 S. Ulster Street - Suite 1500 Denver, Colorado 80237 Project: Mulberry Connection Prepared By: HMO Project Number: 096501004 Checked By: DLS Date: 18-Jan-21 Water Quality Capture Volume - Basin A Contributing Basin Characteristics Site Area =5.39 64% - - Hydrologic Soil Group A = Hydrologic Soil Group B = Hydrologic Soil Group C = Hydrologic Soil Group D = Water Quality Capture Volume FCSCM Equation 7-1 WQ Watershed Inches = a*(0.91i3-1.19i2+.078i) a12 = 0.8 (12-Hr Drain Time) a40 = 1.0 (40-Hr Drain Time) FCSCM Equation 7-2 WQCV = (WQCV/12)*(Area)*1.2 WQCV Impervious (Site) = 64% a =0.8 WQ Watershed Inches (Site) = 0.200 WQCV Area (Site) = 5.39 WQ Capture Volume (Site) = 0.108 AC-FT 0.108 AC-FT 4,702 CU-FT Area (AC) Impervious (%) Watershed Flow Length (ft) Watershed Flow Slope (ft/ft) Site WQ Volume WQCV A (12hr) - 1/19/2021 4582 S. Ulster Street - Suite 1500 Denver, Colorado 80237 Project: Mulberry Connection Prepared By: HMO Project Number: 096501004 Checked By: DLS Date: 18-Jan-21 Water Quality Capture Volume - Basin B1 & B2 Contributing Basin Characteristics Site Area =2.99 89% - - Hydrologic Soil Group A = Hydrologic Soil Group B = Hydrologic Soil Group C = Hydrologic Soil Group D = Water Quality Capture Volume FCSCM Equation 7-1 WQ Watershed Inches = a*(0.91i3-1.19i2+.078i) a12 = 0.8 (12-Hr Drain Time) a40 = 1.0 (40-Hr Drain Time) FCSCM Equation 7-2 WQCV = (WQCV/12)*(Area)*1.2 WQCV Impervious (Site) = 89% a =0.8 WQ Watershed Inches (Site) = 0.314 WQCV Area (Site) = 2.99 WQ Capture Volume (Site) = 0.094 AC-FT 0.094 AC-FT 4,096 CU-FT Site WQ Volume Area (AC) Impervious (%) Watershed Flow Length (ft) Watershed Flow Slope (ft/ft) WQCV B (12hr) - 1/19/2021 4582 S. Ulster Street - Suite 1500 Denver, Colorado 80237 Project: Mulberry Connection Prepared By: HMO Project Number: 096501004 Checked By: DLS Date: 18-Jan-21 Water Quality Capture Volume - Basin C Contributing Basin Characteristics Site Area =3.63 66% - - Hydrologic Soil Group A = Hydrologic Soil Group B = Hydrologic Soil Group C = Hydrologic Soil Group D = Water Quality Capture Volume FCSCM Equation 7-1 WQ Watershed Inches = a*(0.91i3-1.19i2+.078i) a12 = 0.8 (12-Hr Drain Time) a40 = 1.0 (40-Hr Drain Time) FCSCM Equation 7-2 WQCV = (WQCV/12)*(Area)*1.2 WQCV Impervious (Site) = 66% a =0.8 WQ Watershed Inches (Site) = 0.206 WQCV Area (Site) = 3.63 WQ Capture Volume (Site) = 0.075 AC-FT 0.075 AC-FT 3,264 CU-FT Site WQ Volume Area (AC) Impervious (%) Watershed Flow Length (ft) Watershed Flow Slope (ft/ft) WQCV C (12hr) - 1/19/2021 PROJECT NAME: PROJECT NUMBER: 096755001 CALCULATED BY: HMO CHECKED BY: DLS DATE: 1/18/2021 Volume = (D/3)(A + B + (AB)^(1/2)) D=depth between two contours, ft A=area of bottom contour, SF; B=area of top contour, SF ELEV. AREA VOLUME ACCUM. VOL. ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4949.1 747 0 0 0.00 4949.2 4,793 248 248 0.01 4949.3 8,422 652 900 0.02 4949.4 11,741 1,004 1,904 0.04 4949.5 14,816 1,325 3,229 0.07 4949.6 17,737 1,625 4,854 0.11 4949.7 23,738 2,066 6,920 0.16 4949.8 26,581 2,515 9,435 0.22 4949.9 29,289 2,792 12,227 0.28 4950 32,975 3,111 15,339 0.35 4950.1 35,432 3,420 18,758 0.43 4950.2 38,080 3,675 22,433 0.51 4950.3 40,387 3,923 26,356 0.61 4950.4 42,406 4,139 30,495 0.70 4950.5 43,663 8,403 34,759 0.80 4950.6 44,662 8,706 39,201 0.90 4950.7 45,492 8,915 43,674 1.00 4950.8 46,174 9,083 48,284 1.11 4950.9 46,777 9,227 52,900 1.21 4951 47,293 9,347 57,631 1.32 4951.1 47,739 9,451 62,352 1.43 4951.2 48,160 9,545 67,176 1.54 4951.3 48,572 9,631 71,983 1.65 4951.4 48,985 9,714 76,891 1.77 4951.5 49,400 9,797 81,780 1.88 4951.6 49,816 9,880 86,771 1.99 4951.7 50,235 9,963 91,743 2.11 4951.8 50,655 10,047 96,818 2.22 4951.9 51,077 10,131 101,874 2.34 4952 51,739 10,239 107,057 2.46 STAGE-STORAGE ANALYSIS Detention Pond DETENTION BASIN PROJECT NAME:Detention Pond ELEV. AREA VOLUME ACCUM. VOL. ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4951 26 0 0 0.00 4951.1 499 21 21 0.00 4951.2 1,636 101 123 0.00 4951.3 3,565 254 376 0.01 4951.4 6,407 492 868 0.02 4951.5 10,145 820 1,689 0.04 4951.6 14,959 1,247 2,936 0.07 4951.7 21,150 1,797 4,733 0.11 4951.8 29,024 2,498 7,231 0.17 4951.9 38,735 3,376 10,607 0.24 4952 49,359 4,394 15,001 0.34 ELEV. AREA VOLUME ACCUM. VOL. ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4949.1 747 0 0 0.00 4949.2 4,793 248 248 0.01 4949.3 8,422 652 900 0.02 4949.4 11,741 1,004 1,904 0.04 4949.5 14,816 1,325 3,229 0.07 4949.6 17,737 1,625 4,854 0.11 4949.7 23,738 2,066 6,920 0.16 4949.8 26,581 2,515 9,435 0.22 4949.9 29,289 2,792 12,227 0.28 4950 32,975 3,111 15,339 0.35 4950.1 35,432 3,420 18,758 0.43 4950.2 38,080 3,675 22,433 0.51 4950.3 40,387 3,923 26,356 0.61 4950.4 42,406 4,139 30,495 0.70 4950.5 43,663 4,303 34,799 0.80 4950.6 44,662 4,416 39,215 0.90 4950.7 45,492 4,508 43,722 1.00 4950.8 46,174 4,583 48,306 1.11 4950.9 46,777 4,648 52,953 1.22 4951 47,319 4,705 57,658 1.32 4951.1 48,238 4,778 62,436 1.43 4951.2 49,796 4,902 67,337 1.55 4951.3 52,137 5,096 72,434 1.66 4951.4 55,392 5,376 77,809 1.79 4951.5 59,545 5,746 83,555 1.92 4951.6 64,775 6,214 89,769 2.06 4951.7 71,385 6,805 96,574 2.22 4951.8 79,679 7,549 104,124 2.39 4951.9 89,812 8,470 112,593 2.58 4952 101,098 9,540 122,133 2.80 100-YR (2.79 AC-FT) = 4952.00 PARKING LOT PONDING COMBINED VOLUMES PROJECT NAME: PROJECT NUMBER: 096755001 CALCULATED BY: HMO CHECKED BY: DLS DATE: 1/18/2021 Volume = (D/3)(A + B + (AB)^(1/2)) D=depth between two contours, ft A=area of bottom contour, SF; B=area of top contour, SF ELEV. AREA VOLUME ACCUM. VOL. ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4952 522 0 0 0.00 TOP OF MEDIA = 4952 4952.2 929 143 143 0.00 4952.4 1,132 206 349 0.01 4952.6 1,341 247 596 0.01 4952.8 1,558 290 886 0.02 4953 1,783 334 1,220 0.03 RIM OF INLET = 4953 ELEV.AREA VOLUME ACCUM. VOL.ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4952 2,508 0 0 0.00 TOP OF MEDIA = 4952 4952.2 3,409 589 589 0.01 4952.4 3,797 720 1,310 0.03 4952.6 4,160 795 2,105 0.05 4952.8 4,508 867 2,972 0.07 4953 4,849 935 3,907 0.09 RIM OF INLET = 4953 ELEV.AREA VOLUME ACCUM. VOL.ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4952 3,030 0 0 0.00 4952.2 4,339 733 733 0.02 4952.4 4,929 926 1,659 0.04 4952.6 5,502 1,043 2,702 0.06 4952.8 6,066 1,156 3,858 0.09 4953 6,632 1,269 5,127 0.12 REQUIRED WQCV = 4,702 cubic foot RAIN GARDEN A - SOUTH RAIN GARDEN A - COMBINED STAGE-STORAGE ANALYSIS BASIN A RAIN GARDEN A - NORTH PROJECT NAME: PROJECT NUMBER: 096755001 CALCULATED BY: HMO CHECKED BY: DLS DATE: 1/18/2021 Volume = (D/3)(A + B + (AB)^(1/2)) D=depth between two contours, ft A=area of bottom contour, SF; B=area of top contour, SF ELEV. AREA VOLUME ACCUM. VOL. ACCUM. VOL. (FT) (SQ FT.) (CU FT) (CU FT) (AC-FT) 4952 5,731 0 0 0.00 4952.2 6,411 1,214 1,214 0.03 4952.4 7,117 1,352 2,566 0.06 4952.6 7,892 1,500 4,066 0.09 4952.8 8,769 1,665 5,731 0.13 4953 9,733 1,849 7,581 0.17 RIM OF INLET = 4953; REQUIRED WQCV = 3,264 CF STAGE-STORAGE ANALYSIS Rain Garden C RAINGARDEN C Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =64.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.640 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.20 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 234,788 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 =0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region,VWQCV OTHER =cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER =4,702 cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum)DWQCV =12 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =3005 sq ft D) Actual Flat Surface Area AActual =3030 sq ft E) Area at Design Depth (Top Surface Area)ATop =6632 sq ft F) Rain Garden Total Volume VT=4,831 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided?1 B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y=2.3 ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 =4,702 cu ft iii) Orifice Diameter, 3/8" Minimum DO =1 9/16 in Design Procedure Form: Rain Garden (RG) HMO Kimley-Horn January 20, 2021 Mulberry Connection - Basin A Fort Collins, CO UD-BMP (Version 3.07, March 2018) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO UD-BMP_v3.07 A.xlsm, RG 1/20/2021, 12:04 PM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation NO SPRINKLER HEADS ON FLAT SURFACE A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) HMO Kimley-Horn January 20, 2021 Mulberry Connection - Basin A Fort Collins, CO Choose One Choose One Choose One Sheet Flow- No Energy Dissipation Required Concentrated Flow- Energy Dissipation Provided Plantings Seed (Plan for frequent weed control) Sand Grown or Other High Infiltration Sod Choose One YES NO YES NO UD-BMP_v3.07 A.xlsm, RG 1/20/2021, 12:04 PM Culvert Calculator Report Rain Garden A Equalizer Pipe k:\...\eng\drainage\calculations\mulberry2.cvm 03/02/21 01:52:00 PM Kimley Horn and Associates © Bentley Systems, Incorporated Haestad Methods Solution Center Watertown, CT 06795 USA +1-203-755-1666 Project Engineer: heidi.otten@kimley-horn.com CulvertMaster v10.3 [10.03.00.03] Page 1 of 1 Solve For: Headwater Elevation Culvert Summary Allowable HW Elevation 4,953.40 ft Headwater Depth/Height 1.48 Computed Headwater Elevation4,953.85 ft Discharge 17.37 cfs Inlet Control HW Elev. 4,953.72 ft Tailwater Elevation 4,953.00 ft Outlet Control HW Elev. 4,953.85 ft Control Type Outlet Control Grades Upstream Invert 4,952.00 ft Downstream Invert 4,951.80 ft Length 41.00 ft Constructed Slope 0.004878 ft/ft Hydraulic Profile Profile CompositeM2PressureProfile Depth, Downstream 1.20 ft Slope Type Mild Normal Depth N/A ft Flow Regime Subcritical Critical Depth 0.97 ft Velocity Downstream 4.78 ft/s Critical Slope 0.008877 ft/ft Section Section Shape Circular Mannings Coefficient 0.013 Section Material Concrete Span 1.25 ft Section Size 15 inch Rise 1.25 ft Number Sections 3 Outlet Control Properties Outlet Control HW Elev. 4,953.85 ft Upstream Velocity Head 0.35 ft Ke 0.50 Entrance Loss 0.17 ft Inlet Control Properties Inlet Control HW Elev. 4,953.72 ft Flow Control Submerged Inlet Type Square edge w/headwall Area Full 3.7 ft² K 0.00980 HDS 5 Chart 1 M 2.00000 HDS 5 Scale 1 C 0.03980 Equation Form 1 Y 0.67000 Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =66.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.660 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.21 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 158,123 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 =0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region,VWQCV OTHER =cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER =3,264 cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum)DWQCV =12 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =2087 sq ft D) Actual Flat Surface Area AActual =5731 sq ft E) Area at Design Depth (Top Surface Area)ATop =9733 sq ft F) Rain Garden Total Volume VT=7,732 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided?1 B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y=2.3 ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 =3,264 cu ft iii) Orifice Diameter, 3/8" Minimum DO =1 1/4 in Design Procedure Form: Rain Garden (RG) HMO Kimley-Horn January 18, 2021 Mulberry Connection - Basin C Fort Collins, CO UD-BMP (Version 3.07, March 2018) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO UD-BMP_v3.07 C.xlsm, RG 1/18/2021, 9:42 PM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation NO SPRINKLER HEADS ON FLAT SURFACE A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) HMO Kimley-Horn January 18, 2021 Mulberry Connection - Basin C Fort Collins, CO Choose One Choose One Choose One Sheet Flow- No Energy Dissipation Required Concentrated Flow- Energy Dissipation Provided Plantings Seed (Plan for frequent weed control) Sand Grown or Other High Infiltration Sod Choose One YES NO YES NO UD-BMP_v3.07 C.xlsm, RG 1/18/2021, 9:42 PM Va u l t I D To t a l R e q u i r e d WQ V o l u m e ( c f ) Fl o w , W Q (c f s ) i Ch a m b e r T y p e Ch a m b e r R e l e a s e Ra t e a ( c f s ) Ch a m b e r Vo l u m e b ( c f ) In s t a l l e d C h a m b e r w / Ag g r e g a t e c ( c f ) Mi n i m u m N o . o f Ch a m b e r s d To t a l R e l e a s e Ra t e e ( c f s ) Re q u i r e d S t o r a g e V o l u m e b y FA A M e t h o d ( c f ) j Mi n i m u m N o . o f Ch a m b e r s f St o r a g e P r o v i d e d w i t h i n th e C h a m b e r s g ( c f ) To t a l I n s t a l l e d S y s t e m Vo l u m e h ( c f ) 1 4 0 7 1 3 . 5 7 S C - 7 4 0 0 . 0 2 3 5 8 6 4 5 . 9 7 4 . 9 5 5 1 . 3 0 1 0 0 4 2 2 2 5 2 4 . 5 0 4 1 1 9 . 5 0 a. R e l e a s e r a t e p e r c h a m b e r , l i m i t e d b y f l o w t h r o u g h g e o t e x t i l e w i t h a c c u m u l a t e d s e d i m e n t . b. V o l u m e w i t h i n c h a m b e r o n l y , n o t a c c o u n t i n g f o r v o i d s p a c e s i n s u r r o u n d i n g a g g r e g a t e . c. V o l u m e i n c l u d e s c h a m b e r a n d v o i d s p a c e s ( 4 0 % ) i n s u r r o u n d i n g a g g r e g a t e , p e r c h a m b e r u n i t . d. N u m b e r o f c h a m b e r s r e q u i r e d t o p r o v i d e f u l l W Q C V w i t h i n t o t a l i n s t a l l e d s y s t e m , i n c l u d i n g a g g r e g a t e r o u n d e d u p t o n e a r e s t w h o l e n u m b e r e. R e l e a s e r a t e p e r c h a m b e r t i m e s n u m b e r o f c h a m b e r s . f. N u m b e r o f c h a m b e r s r e q u i r e d t o p r o v i d e r e q u i r e d F A A s t o r a g e v o l u m e s t o r e d w i t h i n t h e c h a m b e r o n l y ( n o a g g r e g a t e s t o r a g e ) . g. V o l u m e p r o v i d e d i n c h a m b e r s o n l y ( n o a g g r e g a t e s t o r a g e ) . T h i s n u m b e r m u s t m e e t o r e x c e e d t h e r e q u i r e d F A A s t o r a g e v o l u m e . h. S y s t e m v o l u m e i n c l u d e s t o t a l n u m b e r o f c h a m b e r s , p l u s s u r r o u n d i n g a g g r e g a t e . T h i s n u m b e r m u s t m e e t o r e x c e e d t h e r e q u i r e d W Q C V . i. A s s u m e d 1 / 2 o f t h e 2 - y e a r s t o r m e v e n t t o c a l c u l a t e w a t e r q u a l i t y f l o w . j. A s s u m e d t h e 2 - y e a r s t o r m e v e n t f o r i n t e s i t y v a l u e s i n c a l c u l a t i n g s t o r a g e v o l u m e b y F A A m e t h o d . Ch a m b e r C o n f i g u r a t i o n S u m m a r y PROJECT NAME: Mulberry Connection PROJECT NUMBER:096501004 CALCULATED BY:HMO CHECKED BY:DLS DATE:12/11/2020 3 1.297 0.86 Duration, Td Rainfall Intensity, I Inflow Volume, Vi Outflow Volume, Vo Storage Volume, Vs Storage Volume, Vs (min) (in/hr) (CF) (CF) (CF) (AC-FT) 5 1.43 1103 389 714 0.02 6 1.34 1240 467 773 0.02 7 1.26 1365 545 820 0.02 8 1.20 1486 623 863 0.02 9 1.15 1602 701 902 0.02 10 1.11 1711 778 932 0.02 11 1.07 1813 856 957 0.02 12 1.03 1904 934 970 0.02 13 0.99 1992 1012 980 0.02 14 0.96 2081 1090 991 0.02 15 0.94 2171 1168 1004 0.02 16 0.91 2242 1245 996 0.02 17 0.88 2303 1323 979 0.02 18 0.85 2368 1401 967 0.02 19 0.83 2426 1479 948 0.02 20 0.81 2492 1557 936 0.02 21 0.78 2536 1635 901 0.02 22 0.77 2605 1712 893 0.02 23 0.75 2652 1790 862 0.02 24 0.73 2712 1868 844 0.02 25 0.72 2767 1946 821 0.02 26 0.70 2817 2024 794 0.02 27 0.69 2863 2102 762 0.02 28 0.67 2904 2179 725 0.02 Area (A) acres (Basins B1 & B2) MODIFIED FAA DETENTION SIZING BASIN B WQCV WATER QUALITY CONTROL VOLUME BY MODIFIED FAA METHOD Release Rate (R)' cfs (Total Release Rate From Chamber) 2-Year Runoff Coefficient (C)'Composite of B1 & B2 CALCULATIONS Rating Table for Pond Outlet Orifice Project Description DischargeSolve For Input Data ft3.00Headwater Elevation ft0.45Centroid Elevation ft0.00Tailwater Elevation 0.600Discharge Coefficient ft0.50Opening Width ft0.9Opening Height Velocity (ft/s) Discharge (cfs) Headwater Elevation (ft) (N/A)0.00 3.571.581.00 5.992.652.00 7.693.403.00 Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1/19/2021 FlowMaster [10.03.00.03] Bentley Systems, Inc. Haestad Methods Solution CenterMulberry Connection.fm8 Worksheet for Pond Outlet Orifice Project Description DischargeSolve For Input Data ft3.00Headwater Elevation ft0.45Centroid Elevation ft0.00Tailwater Elevation 0.600Discharge Coefficient ft0.50Opening Width ft0.9Opening Height Results cfs3.40Discharge ft2.55Headwater Height Above Centroid ft-0.45Tailwater Height Above Centroid ft²0.4Flow Area ft/s7.69Velocity Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 1/19/2021 FlowMaster [10.03.00.03] Bentley Systems, Inc. Haestad Methods Solution CenterMulberry Connection.fm8 . Applicable Equations: Lp = (1/2tan )(At/Yt-W) At = Q/V = tan-1(1/(2*ExpansionFactor)) T = 2(Lptan )+W d50 = (0.023Q)/(Yt 1.2Dc 0.3) Assumptions Major event velocity is 5fps for non-cohesive soils and 7fps for erosion resistant soils. Input parameters: Description Variable Input Unit Width of the conduit (use diameter for circular conduits),W (Dc):1.25 ft HGL Elevation (assumed at centerline of pipe)4949.445 ft Invert Elevation 4948.82 ft Tailwater depth (ft),Yt:0.63 ft Expansion angle of the culvert flow : 0.08 radians Design discharge (cfs) Q:2.67 cfs Froude Number F r 0.48 Subcritical Unitless Variables for Tables: For Figure 7.2-2 Q/D2.5 1.53 For Figure 9-35 Yt/D 0.50 For Figure 9-38 Q/WH1.5 1.91 For Figure 9-38 Yt/D 0.50 Allowable non-eroding velocity in the downstream channel (ft/sec) V:5 ft/sec Expansion Factor (Figure 9-35), 1/(2tan())6.5 Solve for: Description Variable Output Unit 1. Required area of flow at allowable velocity (ft2)At:0.53 ft2 2. Length of Protection Lp:-2.57 ft Lp < 3D?Yes Lpmin:3.75 ft 3. Width of downstream riprap protection T: 2.00 ft Rip Rap Size Mean Particle Size Intermediate Dimension (for subcritical flow only)d50 0.10 inches Type from Figure 7.3-1 Type: L Fort Collins Requirements: d50 Minimum:12.00 inches Type: M Equation 9-14 per FCSCM Rip-Rap Apron Calculation Detention Pond 100-Year Outflow Equation 9-10 per FCSCM Equation 9-11 per FCSCM Equation 9-12 per FCSCM Equation 9-13 per FCSCM Stormwater Facility Name: Facility Location & Jurisdiction: User Input: Watershed Characteristics User Defined User Defined User Defined User Defined Watershed Slope =0.010 ft/ft Stage [ft] Area [ft^2] Stage [ft] Discharge [cfs] Watershed Length =1000 ft 0.00 503 0.00 0.04 Watershed Area = 12.31 acres 1.00 862 1.00 0.04 Watershed Imperviousness = 70.0%percent 2.00 1,322 2.00 0.04 Percentage Hydrologic Soil Group A = 0.0%percent 3.00 1,894 3.00 0.04 Percentage Hydrologic Soil Group B = 100.0%percent 4.00 2,619 4.00 0.04 Percentage Hydrologic Soil Groups C/D = 0.0%percent 5.00 31,274 5.00 1.58 5.50 35,432 5.50 2.18 User Input 17 6.00 47,292 6.00 2.65 6.50 49,816 6.50 3.05 7.00 51,508 7.00 3.40 8.00 55,516 8.00 104.86 WQCV Treatment Method =hours After completing and printing this worksheet to a pdf, go to: https://maperture.digitaldataservices.com/gvh/?viewer=cswdif create a new stormwater facility, and attach the pdf of this worksheet to that record. Routed Hydrograph Results Design Storm Return Period =WQCV 2 Year 5 Year 10 Year 50 Year 100 Year One-Hour Rainfall Depth =0.53 0.86 1.14 1.44 2.40 2.93 in Calculated Runoff Volume =0.572 0.797 1.094 2.062 2.640 acre-ft OPTIONAL Override Runoff Volume =acre-ft Inflow Hydrograph Volume =0.571 0.797 1.093 2.061 2.640 acre-ft Time to Drain 97% of Inflow Volume =41.7 41.0 39.9 35.3 32.2 hours Time to Drain 99% of Inflow Volume =45.1 45.8 46.6 47.8 48.2 hours Maximum Ponding Depth =4.88 5.13 5.45 6.29 6.74 ft Maximum Ponded Area =0.63 0.74 0.80 1.12 1.16 acres Maximum Volume Stored =0.432 0.609 0.852 1.683 2.205 acre-ft Stormwater Detention and Infiltration Design Data Sheet Mulberry Connection Detention Pond Fort Collins, CO Location for 1-hr Rainfall Depths (use dropdown): Workbook Protected Worksheet Protected SDI_Design_Data_v1.08_Detention Pond.xlsm, Design Data 4/14/2021, 9:35 AM WQCV_Trigger = 1 RunOnce= 1 CountA=1 Draintime Coeff=1.0 0 1 2 3 #N/A #N/A 0 1 2 3 #N/A #N/A Check Data Set 1 Check Data Set 1 Stormwater Detention and Infiltration Design Data Sheet Area Discharge 0 5 10 15 20 25 30 35 40 45 0.1 1 10 FL O W [ c f s ] TIME [hr] 100YR IN 100YR OUT 50YR IN 50YR OUT 10YR IN 10YR OUT 5YR IN 5YR OUT 2YR IN 2YR OUT WQCV IN WQCV OUT 0 1 2 3 4 5 6 7 8 0.1 1 10 100 PO N D I N G D E P T H [ f t ] DRAIN TIME [hr] 100YR 50YR 10YR 5YR 2YR WQCV SDI_Design_Data_v1.08_Detention Pond.xlsm, Design Data 4/14/2021, 9:35 AM Chapter 12 Storage September 2017 Urban Drainage and Flood Control District 12-33 Urban Storm Drainage Criteria Manual Volume 2 Figure 12-21. Embankment protection details and rock sizing chart (adapted from Arapahoe County) Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.000 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.013 Height of Curb at Gutter Flow Line HCURB =6.00 inches Distance from Curb Face to Street Crown TCROWN =48.0 ft Gutter Width W =2.00 ft Street Transverse Slope SX =0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO =0.015 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX =14.6 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =3.5 5.1 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes Maximum Capacity for 1/2 Street based On Allowable Spread Minor Storm Major Storm Water Depth without Gutter Depression (Eq. ST-2) y = 3.50 4.32 inches Vertical Depth between Gutter Lip and Gutter Flowline (usually 2")dC =2.0 2.0 inches Gutter Depression (dC - (W * Sx * 12))a =1.51 1.51 inches Water Depth at Gutter Flowline d =5.01 5.83 inches Allowable Spread for Discharge outside the Gutter Section W (T - W)TX =12.6 16.0 ft Gutter Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7)EO =0.408 0.330 Discharge outside the Gutter Section W, carried in Section TX QX =5.4 10.3 cfs Discharge within the Gutter Section W (QT - QX)QW =3.7 5.1 cfs Discharge Behind the Curb (e.g., sidewalk, driveways, & lawns)QBACK =0.0 0.0 cfs Maximum Flow Based On Allowable Spread QT =9.1 15.3 cfs Flow Velocity within the Gutter Section V =5.6 6.3 fps V*d Product: Flow Velocity times Gutter Flowline Depth V*d =2.3 3.1 Maximum Capacity for 1/2 Street based on Allowable Depth Minor Storm Major Storm Theoretical Water Spread TTH =8.3 15.0 ft Theoretical Spread for Discharge outside the Gutter Section W (T - W)TX TH =6.3 13.0 ft Gutter Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7)EO =0.670 0.398 Theoretical Discharge outside the Gutter Section W, carried in Section TX TH QX TH =0.8 5.8 cfs Actual Discharge outside the Gutter Section W, (limited by distance TCROWN)QX =0.8 5.8 cfs Discharge within the Gutter Section W (Qd - QX)QW =1.7 3.9 cfs Discharge Behind the Curb (e.g., sidewalk, driveways, & lawns)QBACK =0.0 0.0 cfs Total Discharge for Major & Minor Storm (Pre-Safety Factor) Q =2.6 9.7 cfs Average Flow Velocity Within the Gutter Section V =4.1 5.7 fps V*d Product: Flow Velocity Times Gutter Flowline Depth V*d =1.2 2.4 Slope-Based Depth Safety Reduction Factor for Major & Minor (d > 6") Storm R =1.00 1.00 Max Flow Based on Allowable Depth (Safety Factor Applied)Qd =2.6 9.7 cfs Resultant Flow Depth at Gutter Flowline (Safety Factor Applied)d =3.50 5.10 inches Resultant Flow Depth at Street Crown (Safety Factor Applied)dCROWN =0.00 0.00 inches MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =2.6 9.7 cfs Version 4.06 Released August 2018 ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Enter Your Project Name Here I-25 Fornatge Rd (OS1, O4) Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' UD-Inlet_v4.06 (7).xlsm, I-25 Fornatge Rd (OS1, O4) 3/3/2021, 2:31 PM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK =5.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.080 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.013 Height of Curb at Gutter Flow Line HCURB =6.00 inches Distance from Curb Face to Street Crown TCROWN =40.0 ft Gutter Width W =2.00 ft Street Transverse Slope SX =0.020 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO =0.002 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX =21.7 33.8 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =5.2 8.1 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes Maximum Capacity for 1/2 Street based On Allowable Spread Minor Storm Major Storm Water Depth without Gutter Depression (Eq. ST-2) y = 5.20 8.10 inches Vertical Depth between Gutter Lip and Gutter Flowline (usually 2")dC =2.0 2.0 inches Gutter Depression (dC - (W * Sx * 12))a =1.51 1.51 inches Water Depth at Gutter Flowline d =6.71 9.61 inches Allowable Spread for Discharge outside the Gutter Section W (T - W)TX =19.7 31.8 ft Gutter Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7)EO =0.273 0.171 Discharge outside the Gutter Section W, carried in Section TX QX =6.5 23.3 cfs Discharge within the Gutter Section W (QT - QX)QW =2.4 4.8 cfs Discharge Behind the Curb (e.g., sidewalk, driveways, & lawns)QBACK =0.0 1.0 cfs Maximum Flow Based On Allowable Spread QT =9.0 29.1 cfs Flow Velocity within the Gutter Section V =2.6 3.4 fps V*d Product: Flow Velocity times Gutter Flowline Depth V*d =1.4 2.7 Maximum Capacity for 1/2 Street based on Allowable Depth Minor Storm Major Storm Theoretical Water Spread TTH =15.4 27.5 ft Theoretical Spread for Discharge outside the Gutter Section W (T - W)TX TH =13.4 25.5 ft Gutter Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7)EO =0.388 0.213 Theoretical Discharge outside the Gutter Section W, carried in Section TX TH QX TH =2.3 12.9 cfs Actual Discharge outside the Gutter Section W, (limited by distance TCROWN)QX =2.3 12.9 cfs Discharge within the Gutter Section W (Qd - QX)QW =1.5 3.5 cfs Discharge Behind the Curb (e.g., sidewalk, driveways, & lawns)QBACK =0.0 0.2 cfs Total Discharge for Major & Minor Storm (Pre-Safety Factor) Q =3.8 16.7 cfs Average Flow Velocity Within the Gutter Section V =2.1 3.0 fps V*d Product: Flow Velocity Times Gutter Flowline Depth V*d =0.9 2.0 Slope-Based Depth Safety Reduction Factor for Major & Minor (d > 6") Storm R =1.00 1.00 Max Flow Based on Allowable Depth (Safety Factor Applied)Qd =3.8 16.7 cfs Resultant Flow Depth at Gutter Flowline (Safety Factor Applied)d =5.20 8.10 inches Resultant Flow Depth at Street Crown (Safety Factor Applied)dCROWN =0.00 0.00 inches MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =3.8 16.7 cfs Version 4.06 Released August 2018 ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Enter Your Project Name Here Redman Dr. (O2,O3,O4,OS1,OS2) Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' UD-Inlet_v4.06 (7).xlsm, Redman Dr. (O2,O3,O4,OS1,OS2) 3/3/2021, 2:31 PM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.000 ft/ft Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.013 Height of Curb at Gutter Flow Line HCURB =6.00 inches Distance from Curb Face to Street Crown TCROWN =48.0 ft Gutter Width W =2.00 ft Street Transverse Slope SX =0.009 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO =0.020 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.016 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX =12.5 15.2 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =3.0 3.7 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes Maximum Capacity for 1/2 Street based On Allowable Spread Minor Storm Major Storm Water Depth without Gutter Depression (Eq. ST-2) y = 1.35 1.64 inches Vertical Depth between Gutter Lip and Gutter Flowline (usually 2")dC =2.0 2.0 inches Gutter Depression (dC - (W * Sx * 12))a =1.78 1.78 inches Water Depth at Gutter Flowline d =3.13 3.42 inches Allowable Spread for Discharge outside the Gutter Section W (T - W)TX =10.5 13.2 ft Gutter Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7)EO =0.602 0.502 Discharge outside the Gutter Section W, carried in Section TX QX =1.0 1.9 cfs Discharge within the Gutter Section W (QT - QX)QW =1.5 1.9 cfs Discharge Behind the Curb (e.g., sidewalk, driveways, & lawns)QBACK =0.0 0.0 cfs Maximum Flow Based On Allowable Spread QT =2.6 3.8 cfs Flow Velocity within the Gutter Section V =4.3 4.7 fps V*d Product: Flow Velocity times Gutter Flowline Depth V*d =1.1 1.3 Maximum Capacity for 1/2 Street based on Allowable Depth Minor Storm Major Storm Theoretical Water Spread TTH =11.3 17.4 ft Theoretical Spread for Discharge outside the Gutter Section W (T - W)TX TH =9.3 15.4 ft Gutter Flow to Design Flow Ratio by FHWA HEC-22 method (Eq. ST-7)EO =0.653 0.438 Theoretical Discharge outside the Gutter Section W, carried in Section TX TH QX TH =0.7 2.8 cfs Actual Discharge outside the Gutter Section W, (limited by distance TCROWN)QX =0.7 2.8 cfs Discharge within the Gutter Section W (Qd - QX)QW =1.4 2.2 cfs Discharge Behind the Curb (e.g., sidewalk, driveways, & lawns)QBACK =0.0 0.0 cfs Total Discharge for Major & Minor Storm (Pre-Safety Factor) Q =2.1 5.0 cfs Average Flow Velocity Within the Gutter Section V =4.2 5.0 fps V*d Product: Flow Velocity Times Gutter Flowline Depth V*d =1.0 1.5 Slope-Based Depth Safety Reduction Factor for Major & Minor (d > 6") Storm R =1.00 1.00 Max Flow Based on Allowable Depth (Safety Factor Applied)Qd =2.1 5.0 cfs Resultant Flow Depth at Gutter Flowline (Safety Factor Applied)d =3.00 3.65 inches Resultant Flow Depth at Street Crown (Safety Factor Applied)dCROWN =0.00 0.00 inches MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Spread Criterion Qallow =2.1 3.8 cfs Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Version 4.06 Released August 2018 ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Enter Your Project Name Here I-25 Frontage Rd (OS3) UD-Inlet_v4.06 (7).xlsm, I-25 Frontage Rd (OS3) 3/3/2021, 2:31 PM 21 APPENDIX E Geotechnical Evaluation Proposed Poudre Valley Development Redman Drive and NW Frontage Road Fort Collins, Colorado Comunale Properties 1855 South Pearl Street, Suite 20 | Denver, Colorado 80210 July 2, 2019 | Project No. 501710001 1855 South Pearl Street, Suite 20 | Denver, Colorado 80210 | Project No. 501710001 Kelley Lange, EI Senior Staff Engineer Brian F. Gisi, PE Principal Engineer Geotechnical Evaluation Proposed Poudre Valley Development Redman Drive and NW Frontage Road Fort Collins, Colorado Mr. Josh Heiney Comunale Properties 1855 South Pearl Street, Suite 20 | Denver, Colorado 80210 July 2 , 2019 | Project No. 501710001 KL/BFG/lm Distribution: (1) Addressee (via e-mail) 6001 South Willow Drive, Suite 195 | Greenwood Village, Colorado 80111 | p. 303.629.6000 |www.ninyoandmoore.com 07/2/2019 Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 i CONTENTS 1 INTRODUCTION 1 2 SCOPE OF SERVICES 1 3 SITE DESCRIPTION AND BACKGROUND REVIEW 2 4 PROPOSED CONSTRUCTION 2 5 FIELD EXPLORATION AND LABORATORY TESTING 2 6 GEOLOGY AND SUBSURFACE CONDITIONS 3 6.1 Geologic Setting 3 6.2 Subsurface Conditions 3 6.2.1 Loam 3 6.2.2 Alluvium 4 6.3 Groundwater 4 7 GEOLOGIC HAZARDS 4 7.1 Faulting and Seismicity 4 7.2 Expansive Soils 6 7.3 Compressible/Collapsible Soils 7 7.4 Liquefaction Potential 7 8 CONCLUSIONS 8 9 RECOMMENDATIONS 9 9.1 Earthwork 9 9.1.1 Excavations 9 9.1.2 Site Grading 10 9.1.3 Re-Use of Site Soils 11 9.1.4 Fill Placement and Compaction 11 9.1.5 Imported Soil 12 9.1.6 Controlled Low Strength Material 12 9.1.7 Utility Installation 13 9.1.8 Temporary Cut Slopes 14 9.2 Spread Footing Foundations 14 9.3 Slab-On-Grade Floors 15 9.4 Earth Pressures and Below-Grade Walls 17 Compressible/Collapsible SoilsCompressible/Collapsible Soils Liquefaction PotentialLiquefaction Potential CONCLUSIONSCONCLUSIONS RECOMMENDATIONSRECOMMENDATIONS 9.1 Earthwork9.1 Earthwork ExcavationsExcavations Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 ii 9.5 Pavements 17 9.5.1 Pavement Design 18 9.5.2 Dolly Pads 20 9.5.3 Pavement Subgrade Preparation 20 9.5.4 Pavement Materials 21 9.5.5 Pavement Maintenance 21 9.6 Concrete Flatwork 22 9.7 Corrosion Considerations 23 9.7.1 Concrete 23 9.7.2 Buried Metal Pipes 24 9.8 Scaling 24 9.9 Frost Heave 25 9.10 Construction in Cold or Wet Weather 25 9.11 Site Drainage 26 9.12 Construction Observation and Testing 26 9.13 Plan Review 27 9.14 Pre-Construction Meeting 27 10 LIMITATIONS 27 11 REFERENCES 29 TABLES 1 – 2015 International Building Code Seismic Design Criteria 5 2 – Slab Performance Risk Categories 6 3 – Lateral Earth Pressures 17 4 – Recommended Pavement Thickness 19 FIGURES 1 – Site Location 2 – Boring Locations APPENDICES A – Boring Logs B – Laboratory Testing Construction in Cold or Wet WeatherConstruction in Cold or Wet Weather Construction Observation and TestingConstruction Observation and Testing Construction Meeting International Building Code Seismic Design CriteriaInternational Building Code Seismic Design Criteria Slab Performance Risk CategoriesSlab Performance Risk Categories teral Earth Pressuresteral Earth Pressures Recommended Pavement ThicknessRecommended Pavement Thickness Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 1 1 INTRODUCTION In accordance with your authorization and our proposal dated May 29, 2019, we have performed a geotechnical evaluation for the proposed Poudre Valley Development located on the northwest corner of the intersection of Redman Drive and the NW Frontage Road in Fort Collins, Colorado. The approximate location of the site is depicted on Figure 1. The purpose of our study was to evaluate the subsurface conditions and to provide design and construction recommendations regarding geotechnical aspects of the proposed project. This report presents the findings of our subsurface exploration program, results of our laboratory testing, conclusions regarding the subsurface conditions at the site, and geotechnical recommendations for design and construction of this project. 2 SCOPE OF SERVICES The scope of our services for the project generally included: Review of referenced background information, including aerial imagery, published geologic and maps, in-house geotechnical data, and available topographical information pertaining to the project site and vicinity. Performance of a geologic reconnaissance and mark-out of the boring locations at the project site. Notification of Utility Notification Center of Colorado of the boring locations prior to drilling. Drilling, logging, and sampling of 17 small-diameter exploratory borings within the project site to depths ranging between approximately 15.5 and 20.5 feet below ground surface (bgs). The boring logs are presented in Appendix A. Boring locations are presented on Figure 2. Performance of laboratory tests on selected samples obtained from the borings to evaluate engineering properties including in-situ moisture content and dry density, Atterberg limits, percent materials finer than the No. 200 sieve and gradation, consolidation/swell potential, and soil corrosivity characteristics (including pH, resistivity, water soluble sulfates, and chlorides). The results of the laboratory testing are presented on the boring logs and in Appendix B. Compilation and analysis of the data obtained. Preparation of this report presenting our findings, conclusions, and geotechnical recommendations regarding design and construction of the project. he scope of our services for the project generally included:he scope of our services for the project generally included: Review of referenced background information, including aerial imagery, published geologic Review of referenced background information, including aerial imagery, published geologic house geotechnical data, and available topographical information pertaining to house geotechnical data, and available topographical information pertaining to Performance of a geologic reconnaissance and markPerformance of a geologic reconnaissance and mark Notification of Utility Notification Center of Colorado of the boring locations prior to drilling. Notification of Utility Notification Center of Colorado of the boring locations prior to drilling. illing, logging, and sampling of illing, logging, and sampling of 1717 small site to depths ranging between approximately 15.5 and 20.5site to depths ranging between approximately 15.5 and 20.5 (bgs). The boring logs are presented in Appendix A. Boring locations are presented on (bgs). The boring logs are presented in Appendix A. Boring locations are presented on Performance of laboratory tests on selected samples obtained from the borings to evaluate Performance of laboratory tests on selected samples obtained from the borings to evaluate Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 2 3 SITE DESCRIPTION AND BACKGROUND REVIEW The site is an approximately 20-acre parcel of land in Fort Collins, Colorado. The project site is bounded by agricultural land followed by East Vine Drive to the north, by the NW Frontage Road to the east, by Redman Drive to the south, and by a creek followed by agricultural land to the west. The site is approximately 2.5 miles southeast of Lindenmeier Lake and Long Pond Reservoir. The project site was used as farmland at the time of our subsurface exploration. Aerial photograph review indicates that the subject site has existed similar to its current condition since 1999 or earlier. The approximate location of the site is presented on Figure 1. 4 PROPOSED CONSTRUCTION The development of the site includes the design and construction of two industrial buildings with plan areas ranging from approximately 74,400 to 94,000 square feet (sf). Ancillary construction of pavement areas surrounding the development and an approximately 40,500 sf detention pond are also anticipated. Based on the site conditions and the anticipated construction, cut/fill thicknesses of generally less than 5 feet are anticipated for the development. Deeper cut/fill should be anticipated for deeper utilities. Detailed information regarding the finished floor elevations and anticipated loading information was not available for review at the time of this report. 5 FIELD EXPLORATION AND LABORATORY TESTING On June 3, 2019, Ninyo & Moore conducted a subsurface exploration at the site to evaluate the existing subsurface conditions and to collect soil samples for laboratory testing. The evaluation consisted of the drilling, logging, and sampling of 17 small-diameter borings using a truck- mounted drill rig equipped with 4-inch diameter solid-stem augers. The borings were drilled to depths ranging between approximately 15.5 and 20.5 feet bgs. The approximate locations of the borings are presented on Figure 2. Relatively undisturbed and disturbed soil samples were collected at selected intervals. The sampling methods used during the subsurface evaluation are presented in Appendix A. Soil samples collected during the subsurface exploration were transported to the Ninyo & Moore laboratory for geotechnical laboratory analyses. Selected samples were analyzed to evaluate engineering properties including in-situ moisture content and dry density, Atterberg limits, percent materials finer than the No. 200 sieve and gradation, swell/consolidation potential, and he development of the site includes the design and construction of two industrial buildings with he development of the site includes the design and construction of two industrial buildings with plan areas ranging from approximately 74,400 to 94,000 square feet (sf). Ancillary construction plan areas ranging from approximately 74,400 to 94,000 square feet (sf). Ancillary construction of pavement areas surrounding the development and an approximately 40,500 sf detention of pavement areas surrounding the development and an approximately 40,500 sf detention Based on the site conditions and the anticipated construction, cBased on the site conditions and the anticipated construction, c feet are anticipated for the feet are anticipated for the developmentdevelopment. Deeper cut/fill should be anticipated for Deeper cut/fill should be anticipated for Detailed information regarding the finished floor elevations and anticipated Detailed information regarding the finished floor elevations and anticipated loading information was not available for review at tloading information was not available for review at t FIELD EXPLORATION ANFIELD EXPLORATION AN Ninyo & Moore conducted Ninyo & Moore conducted existing subsurface conditions and to collect soil samples for laboratory testing. The evaluatioexisting subsurface conditions and to collect soil samples for laboratory testing. The evaluatio Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 3 soil corrosivity characteristics (including resistivity, pH, water soluble sulfates and chlorides). The results of the in-situ moisture content and dry density tests are presented on the boring logs in Appendix A. Descriptions of the laboratory test methods and the remainder of the test results are presented in Appendix B. 6 GEOLOGY AND SUBSURFACE CONDITIONS The geology and subsurface conditions at the site are described in the following sections. 6.1 Geologic Setting The site is located approximately 9 miles east of the Rocky Mountain Front Range, within the Colorado Piedmont section of the Great Plains Physiographic Province. The Laramide Orogeny uplifted the Rocky Mountains during the late Cretaceous and early Tertiary Periods. Subsequent erosion deposited sediments east of the Rocky Mountains, including the Pierre Shale in the area. As a result of regional uplift approximately 5 to 10 million years ago streams, such as the South Platte River, downcut and excavated into the Great Plains forming the Colorado Piedmont section (Trimble, 1980). The surficial geology of the site is mapped by Colton (1978) as Pleistocene-age Broadway Alluvium generally consisting of sand and gravel. The Pierre Shale bedrock is mapped as underlying the site at depth. 6.2 Subsurface Conditions Our understanding of the subsurface conditions at the project site is based on our field exploration, laboratory testing, review of published geologic maps, historic aerial imagery, and our experience with the general geology of the area. The following sections provide a generalized description of the subsurface materials encountered. More detailed descriptions are presented on the boring logs in Appendix A. 6.2.1 Loam Loam was encountered at the surface in each boring and extended to depths between approximately 2 and 9 feet bgs. The loam generally consisted of various shades of brown, white, and red, moist, firm to very stiff, fat clay with varying amounts of sand and gravel and lean clay with varying amounts of sand and gravel. As the site is used for agricultural purposes, a surficial plow zone with loosened soil should be anticipated. Colorado Piedmont section of the Great Plains Physiographic Province. The Laramide Orogeny Colorado Piedmont section of the Great Plains Physiographic Province. The Laramide Orogeny ocky Mountains during the late Cretaceous and early Tertiary Periods. Subsequent ocky Mountains during the late Cretaceous and early Tertiary Periods. Subsequent erosion deposited sediments east of the Rocky Mountains, including the Pierre Shaleerosion deposited sediments east of the Rocky Mountains, including the Pierre Shale area. As a result of regional uplift approximately 5 to 10 million years agoarea. As a result of regional uplift approximately 5 to 10 million years ago downcut and excavated into the Great Plains forming the Colorado Piedmont downcut and excavated into the Great Plains forming the Colorado Piedmont The surficial geology of the site is mapped by The surficial geology of the site is mapped by Colton (1978Colton (1978 generally consisting of sgenerally consisting of sand and graveland and gravel.The Subsurface ConditionsSubsurface Conditions Our understanding of the subsurface conditions at the project site is based on our field Our understanding of the subsurface conditions at the project site is based on our field exploration, laboratory testing, review of published geologicexploration, laboratory testing, review of published geologic our experience with the general geology of the area. The following sections provide a our experience with the general geology of the area. The following sections provide a Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 4 Based on the results of the laboratory testing, selected samples of the loam generally exhibited moderate to high plasticity, had in-place moisture contents ranging from approximately 10.4 to 21.9 percent, and dry densities ranging from approximately 102.0 to 119.9 pounds per cubic foot (pcf). 6.2.2 Alluvium Alluvium was encountered in each boring beneath the loam and extended to the borings’ termination depths of up to approximately 20.5 feet bgs. The alluvium was generally composed of various shades of brown, red, yellow, and gray, moist to wet, very loose to very dense, fine to coarse sand with varying amounts of clay, silt, and gravel, and firm to stiff, sandy, silty clay and sandy lean and fat clay. Based on the laboratory test results, the selected samples of the alluvium had in-place moisture contents ranging from approximately 1.1 to 27.0 percent and dry densities ranging from approximately 93.9 to 128.1 pcf. 6.3 Groundwater Groundwater was encountered in our borings at depths ranging between approximately 8.5 and 12 feet bgs during drilling. Groundwater levels can fluctuate due to seasonal variations, precipitation, irrigation, groundwater withdrawal or injection, and other factors. Depending on the time of year construction occurs, groundwater, particularly perched groundwater within the upper loam soils, could be encountered. However, based on the knowledge of the area and the results of our subsurface exploration, groundwater is not considered to be a constraint to the construction of this project, but may be encountered during deep utility excavation and installation. 7 GEOLOGIC HAZARDS The following sections describe potential geologic hazards at the site including faulting and seismicity, expansive soils, compressible/collapsible soils, and liquefaction potential. 7.1 Faulting and Seismicity Historically, several minor earthquakes have been recorded around the Front Range area. Based on our field observations and our review of readily available published geological maps and literature there are no known active faults underlying or adjacent to the subject site. The faults closest to the project site include the Walnut Creek and Rock Creek Faults and the Golden Fault. Based on the laboratory test results, the selected samples of the Based on the laboratory test results, the selected samples of the 1.1 to 27.01.1 to 27.0 percent and dry densities ranging percent and dry densities ranging dwater was encountered in our boringsdwater was encountered in our borings at depths ranging between approximately 8.5 and at depths ranging between approximately 8.5 and 12 feet bgs during drilling. Groundwater 12 feet bgs during drilling. Groundwater levels can fluctuate duelevels can fluctuate due precipitation, irrigation, groundwater withdrawal or injection, and other factors. Depending on the precipitation, irrigation, groundwater withdrawal or injection, and other factors. Depending on the time of year construction occurs, groundwater, particularly perched groundwater within the time of year construction occurs, groundwater, particularly perched groundwater within the could be encountered. However, based on the knowledge of the area and the could be encountered. However, based on the knowledge of the area and the results of our subsurface exploration, groundwater is not considered to be a constraint to the results of our subsurface exploration, groundwater is not considered to be a constraint to the construction of this project, but may be encountered during deep utility excavation and construction of this project, but may be encountered during deep utility excavation and Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 5 The Rock Creek and Walnut Creek Faults lay approximately 45 miles southwest of the site (Widmann, Kirkham, and Rogers, 1998). Both faults are mapped as 3 kilometer long reverse faults with slip rates of less than 0.2 millimeters per year. Both Faults are located in the High Plains region, just east of the Front Range. They are downthrown to the southeast and may become listric at depth where it is floored within the Laramie Formation (Risk Engineering, 1994). The surface of the Quaternary-age alluvium above the bedrock does not appear to be displaced so there is not strong evidence of Quaternary faulting. The Golden Fault lies approximately 50 miles southwest of the site. The fault is considered to be late Quaternary in age and has not shown displacement in Holocene time, as Pleistocene deposits overlie the fault (approximately 75 to 125 thousand years before the present [Kirkham, 1977]). Therefore, the probability of damage at the site from seismically induced ground surface rupture from this fault is considered to be low. Design of any proposed improvements should be performed in accordance with the requirements of the governing jurisdictions and applicable building codes. Table 1 presents the preliminary seismic design parameters for the site in accordance with the 2015 International Building Code guidelines and adjusted maximum considered earthquake spectral response acceleration parameters evaluated using the web-based OSHPD ground motion calculator (OSHPD, 2019). Table 1 – 2015 International Building Code Seismic Design Criteria Seismic Design Factors Value Site Class D Site Coefficient, Fa 1.6 Site Coefficient, Fv 2.4 Mapped Spectral Acceleration at 0.2-second Period, Ss 0.178 g Mapped Spectral Acceleration at 1.0-second Period, S1 0.057 g Spectral Acceleration at 0.2-second Period Adjusted for Site Class, SMS 0.284 g Spectral Acceleration at 1.0-second Period Adjusted for Site Class, SM1 0.137 g Design Spectral Response Acceleration at 0.2-second Period, SDS 0.190 g Design Spectral Response Acceleration at 1.0-second Period, SD1 0.092 g 1977]). Therefore, the probability of damage at the site from seismically induced ground surface 1977]). Therefore, the probability of damage at the site from seismically induced ground surface proposed improvements should be performed in accordance with the proposed improvements should be performed in accordance with the requirements of the governing jurisdictions and applicable building codes.requirements of the governing jurisdictions and applicable building codes. seismic design parameters for the site in accordance with the seismic design parameters for the site in accordance with the Building Code guidelines and adjusted maximum considered earthquake spectral response Building Code guidelines and adjusted maximum considered earthquake spectral response acceleration parameters evaluated using the webacceleration parameters evaluated using the web--based based OO International Building Code Seismic Design Criteria Seismic Design Factors Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 6 7.2 Expansive Soils One of the more significant geologic hazards in Colorado is the presence of swelling clays in bedrock or surficial deposits. Moisture changes to bedrock or surficial deposits containing swelling clays can result in volumetric expansion and collapse of those units. Changes in soil moisture content can result from rainfall, irrigation, pipeline leakage, surface drainage, perched groundwater, drought, or other factors. Volumetric change of expansive soil may cause excessive cracking and heaving of structures with shallow foundations, concrete slabs-on- grade, or pavements supported on these materials. Construction on soils known to be potentially expansive could have a significant impact to the project. A review of a Colorado Geological Survey map delineating areas based on their relative potential for swelling in the Front Range area by Hart (1973-1974) indicates soil and bedrock materials in the project vicinity typically exhibit low swell potential. Based on the results of our laboratory testing, the loam deposits exhibited swell percentages of up to approximately 5 percent when inundated against surcharge pressures of 200 pounds per square foot (psf). The alluvial deposits exhibited swell percentages of up to approximately 1.5 percent at surcharge pressures of 500 psf. Based on the results of our subsurface exploration, laboratory testing, and the information obtained from our background review, the on-site soils expected to be encountered during project development would have a slab performance risk category of “LOW”, based on the criteria presented in Table 2. Recommendations intended to reduce the risk for post- construction movement due to swelling soils are included in this report. Table 2 – Slab Performance Risk Categories Slab Performance Risk Category Representative Percent Swell (500 psf Surcharge) Representative Percent Swell (1,000 psf Surcharge) LOW 0 to <3 0 to <2 MODERATE 3 to <5 2 to <4 HIGH 5 to <8 4 to <6 VERY HIGH > 8 > 6 Note:Based on Colorado Association of Geotechnical Engineers, Guidelines for Slab Performance Risk Evaluation and Residential Basement Floor System Recommendations (Denver Metropolitan Area, 1996). Slab Performance Risk Categories 1974) indicates soil and bedrock 1974) indicates soil and bedrock swell potential.swell potential. loam deposits exhibited swell loam deposits exhibited swell against surcharge pressures of against surcharge pressures of exhibited swell exhibited swell percentagespercentages percent at surcharge pressures of 500 psf. Based on the results of our subsurface exploration, laboratory testing, and the information Based on the results of our subsurface exploration, laboratory testing, and the information ned from our background review, the onned from our background review, the on--site soils expected to be encountered during site soils expected to be encountered during project development would have a slab performance risk category ofproject development would have a slab performance risk category of criteria presented in Table 2. Recommendations intended to reduce the risk for postcriteria presented in Table 2. Recommendations intended to reduce the risk for post onstruction movement due to swelling soils are included in this report.onstruction movement due to swelling soils are included in this report. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 7 We recommend supporting the proposed buildings on shallow foundations and slab-on-grade floors bearing on a zone of moisture conditioned and compacted fill material (i.e., fill prism). The recommendations provided in this report assume supporting the proposed improvements on a fill prism is acceptable to the Owner and can be accommodated by the structural design. It should be recognized that the proposed buildings may experience distortions of approximately 1-inch (vertical) over 50 feet (horizontal) due to the swell potential of the on-site soils that will be used to construct the fill prism. Failure to follow the site drainage recommendations provided in Section 9.10 may also result in additional building movement that is difficult to quantify. 7.3 Compressible/Collapsible Soils Compressible soils are generally comprised of soils that undergo consolidation when exposed to new loadings, such as fill or foundation loads. Soil collapse (or hydro-collapse) is a phenomenon where soils undergo a significant decrease in volume upon an increase in moisture content, with or without an increase in external loads. Buildings, structures, and other improvements may be subject to excessive settlement-related distress when compressible soils or collapsible soils are present. Based on our subsurface evaluation, the results of our laboratory testing, and provided the recommendations provided herein are followed, it is our opinion post-construction settlements due to the imposed foundation loads will be within generally accepted construction practices. 7.4 Liquefaction Potential Liquefaction is a phenomenon in which loose, saturated soils lose shear strength under short- term (dynamic) loading conditions. Ground shaking of sufficient duration results in the loss of grain-to-grain contact in potentially liquefiable soils due to a rapid increase in pore water pressure, causing the soil to behave as a fluid for a short period of time. To be potentially liquefiable, a soil is typically cohesionless with a grain-size distribution generally consisting of sand and silt. It is generally loose to medium dense and has a relatively high moisture content, which is typical near or below groundwater level. The potential for liquefaction decreases with increasing clay and gravel content, but increases as the ground acceleration and duration of shaking increase. Potentially liquefiable soils need to be subjected to sufficient magnitude and duration of ground shaking for liquefaction to occur. Based on our subsurface exploration, laboratory testing, and the relatively low ground motion anticipated at the site, liquefaction is not considered a hazard at this site. to new loadings, such as fill or foundation loads. Soil collapse (or hydroto new loadings, such as fill or foundation loads. Soil collapse (or hydro phenomenon where soils undergo a significant decrease in volume upon an increase in phenomenon where soils undergo a significant decrease in volume upon an increase in moisture content, with or without an increase in external loads. moisture content, with or without an increase in external loads. BuildingsBuildings, structures, and other improvements may be subject to excessive settlementimprovements may be subject to excessive settlement-related distress when compressible soils related distress when compressible soils the results of our the results of our laboratorylaboratory recommendations provided herein are followed, it is our opinion recommendations provided herein are followed, it is our opinion due to the imposed foundation loads will be within generally accepted construction practices.due to the imposed foundation loads will be within generally accepted construction practices. Liquefaction PotentialLiquefaction Potential Liquefaction is a phenomenon in which loose, saturated soils lose shear strength under shortLiquefaction is a phenomenon in which loose, saturated soils lose shear strength under short term (dynamic) loading conditions. Ground shaking of sufficient duration results in the losterm (dynamic) loading conditions. Ground shaking of sufficient duration results in the los grain contact in potentially liquefiable soils due to a rapid increase in pore water grain contact in potentially liquefiable soils due to a rapid increase in pore water pressure, causing the soil to behave as a fluid for a short period of time. pressure, causing the soil to behave as a fluid for a short period of time. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 8 8 CONCLUSIONS Based on the results of the subsurface evaluation, laboratory testing, and data analyses, it is our opinion that the proposed project is feasible from a geotechnical standpoint, provided the recommendations presented herein are implemented and appropriate construction practices are followed. Geotechnical design and construction considerations for the proposed project include the following: Loam was encountered at the surface in each boring and extended to depths between approximately 2 and 9 feet bgs. The loam generally consisted of various shades of brown, white, and red, moist, firm to very stiff, fat clay with varying amounts of sand and gravel and lean clay with varying amounts of sand and gravel. Laboratory testing indicates the loam deposits exhibit high swell potential. Alluvium was encountered in each boring beneath the loam and extended to the borings’ termination depths of up to approximately 20.5 feet bgs. The alluvium was generally composed of various shades of brown, red, yellow, and gray, moist to wet, very loose to very dense, fine to coarse sand with varying amounts of clay, silt, and gravel, and firm to stiff, sandy, silty clay and sandy lean and fat clay. Laboratory testing indicates the alluvial deposits exhibit low swell potential. Based on our aerial imagery review, the site has been used for agricultural purposes since 1999 or earlier. A plow zone should be anticipated at the subgrade level. The loosened soil within the plow zone should be removed and recompacted as engineered fill. As an alternative to deep foundation systems, overlot grading improvements should be designed carefully so that the swelling soils are removed and replaced to create a zone of low-swelling material below the proposed structures and surface improvements. Chemical treatment of pavement subgrade could also be considered to reduce the swell potentials. The on-site soils should generally be excavatable with medium- to heavy-duty earthmoving or excavating equipment in good operating condition. Groundwater was encountered at depths ranging between approximately 8.5 and 12 feet bgs during drilling. Groundwater levels will fluctuate due to seasonal variations from precipitation, irrigation, groundwater withdrawal or injection, and other factors. In general, groundwater is not anticipated to be a constraint to the proposed construction but may be encountered during excavation and installation of deep utilities. Based on our laboratory data and our experience with similar materials at adjacent sites, the sulfate content of the tested soils presents a moderate risk of sulfate attack to concrete. We recommend the use of Type II cement for construction of concrete structures at this site. Based on our laboratory data and our experience with similar materials at adjacent sites, the subgrade soils at the site are moderately corrosive to ferrous metals. Therefore, special consideration should be given to the use of heavy gauge, corrosion-protected, underground steel pipe or culverts, if any are planned. As an alternative, plastic pipe or reinforced concrete pipe could be considered. A corrosion specialist should be consulted for further recommendations. No known or reported active faults are reported underlying, or adjacent to, the site. Based on the low ground motion hazard, the likelihood or potential for liquefaction is considered to was encountered in each boring beneath the loamwas encountered in each boring beneath the loam and extended to the boringand extended to the boring 20.5 feet bgs. 20.5 feet bgs. The composed of various shades of brown, red, yellow, and graycomposed of various shades of brown, red, yellow, and gray,,moist to wet, very loose to very moist to wet, very loose to very dense, fine to coarse sand with varying amounts of clay, silt, and gravel, and dense, fine to coarse sand with varying amounts of clay, silt, and gravel, and Laboratory testing indicates the Laboratory testing indicates the he site has as beenbeen used for agricultural purposes w zone should be anticipated at the subgrade level. The loosened soil w zone should be anticipated at the subgrade level. The loosened soil within the plow zone should be removed and recompacted as engineered fill.within the plow zone should be removed and recompacted as engineered fill. As an alternative to deep foundation systems, overlot grading improvements should be As an alternative to deep foundation systems, overlot grading improvements should be the swelling soils are the swelling soils are removed swelling material below the proposed structures and surface improvements. swelling material below the proposed structures and surface improvements. treatment of pavement subgrade could also be considered treatment of pavement subgrade could also be considered s should generally be excavatable with s should generally be excavatable with or excavating equipment in good operating or excavating equipment in good operating Groundwater was encountered at depths ranging between approximately 8.5 and 12 feet Groundwater was encountered at depths ranging between approximately 8.5 and 12 feet Groundwater levels will fluctuate due to seasonal variations from Groundwater levels will fluctuate due to seasonal variations from precipitation, irrigation, groundwater withdrawal or injection, and other factors. precipitation, irrigation, groundwater withdrawal or injection, and other factors. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 9 be negligible and therefore not a design consideration. 9 RECOMMENDATIONS Based on our understanding of the project, the following sections present our geotechnical recommendations for design and construction of the proposed buildings and other site improvements. 9.1 Earthwork The following sections provide our earthwork recommendations for this project. We anticipate the site grading may consist of material cuts and fills on the order of 5 feet. Deeper cuts and fills may be needed to install buried utilities. 9.1.1 Excavations Our evaluation of the excavation characteristics of the on-site materials is based on the results of the subsurface exploration, our site observations, and our experience with similar materials. The on-site surface and near surface soils (loam and alluvium) may generally be excavated with moderate- to heavy-duty earthmoving or excavation equipment in good operating condition. Equipment and procedures that do not cause significant disturbance to the excavation bottoms should be used. Excavators and backhoes with buckets having large claws to loosen the soil should be avoided when excavating the bottom approximately 6 to 12 inches of excavations as such equipment may disturb the excavation bases. The site has been used as agriculture fields. It should be anticipated that loose and disturbed soil will be encountered at the subgrade level which will need to be compacted and moisture-conditioned prior to fill placement. The contractor should provide safely sloped excavations or an adequately constructed and braced shoring system, in compliance with Occupational Safety and Health Administration (OSHA) (OSHA, 2005) guidelines, for employees working in an excavation that may expose employees to the danger of moving ground. If material is stored or equipment is operated near an excavation, stronger shoring should be used to resist the extra pressure due to superimposed loads. Our evaluation of the excavation characteristics of the onOur evaluation of the excavation characteristics of the on-site materials is based on the site materials is based on the results of the subsurface exploration, our site observations, and our experience with similar results of the subsurface exploration, our site observations, and our experience with similar site surface and near surface soils (loam and site surface and near surface soils (loam and duty earthmoving or excavation equipment in good duty earthmoving or excavation equipment in good proceduresprocedures that do that do not cause significant disturbance to the excavation cause significant disturbance to the excavation bottoms should be used. Excavators and backhoes with buckets having large claws to bottoms should be used. Excavators and backhoes with buckets having large claws to loosen the soil should be avoided when excavating the bottom approximately 6 to 12 inches loosen the soil should be avoided when excavating the bottom approximately 6 to 12 inches of excavations as such equipment mayof excavations as such equipment may The site has been used as agriculture fields. It should be anticipated that loose and The site has been used as agriculture fields. It should be anticipated that loose and disturbed soil will be encountered at the subgrade level which will need to be compacted disturbed soil will be encountered at the subgrade level which will need to be compacted Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 10 9.1.2 Site Grading Prior to grading, the ground surface in proposed structure and improvement areas should be cleared of any surface obstructions, debris, topsoil, organics (including vegetation), and other deleterious material. Materials generated from clearing operations should be removed from the project site for disposal (e.g. at a legal landfill site). Obstructions that extend below finish grade, if present, should be removed and resulting voids filled with compacted, engineered fill or Controlled Low Strength Material (CLSM). The proposed buildings may be supported on shallow foundation systems consisting of spread-footings bearing on a relatively uniform thickness of moisture-conditioned and compacted engineered fill extending to 12 or more inches below the bottom of the footings. The buildings may be provided with slab-on-grade floors bearing 3 or more feet of moisture conditioned and compacted engineered fill. The limits of this fill layer should extend 5 or more feet out beyond the footings to reduce the swell potential within the structures, as well as the surrounding building appurtenances, such as exterior flatwork adjacent to the building. There are risks associated with supporting pavements over expansive soils without soil modification. However, the costs associated with remediating pavement subgrades for expansive soils are generally considered cost-prohibitive. Therefore, the following recommendation for pavement subgrade preparation is provided assuming the owner is willing to accept some risk of poor pavement performance as a result of post-construction vertical movements associated with the high swell potential of the overburden soils. Asphalt and concrete pavements and flatwork may be placed on 24 or more inches of moisture conditioned and compacted engineered fill. As an alternative, the upper 12 or more inches of subgrade below the pavements sections could be chemically treated using fly ash or lime to reduce plasticity, reduce swell-potential, and increase strength of the treated subgrade soils. The geotechnical consultant should be retained to observe the remedial excavations, and the elevations of the excavation bottoms should be surveyed by the project civil engineer. The exposed subgrade materials should be firm and unyielding prior to fill placement. The extent of and depths of removal should be evaluated by our representative during the excavation work based on observation of the soils exposed. Additional recommendations below the bottom of the footings. below the bottom of the footings. grade floors bearing grade floors bearing 3 or more feet of The limits of thisThe limits of this fill layer should extend fill layer should extend more feet out beyond the footings to reduce the swell potentialmore feet out beyond the footings to reduce the swell potential within the structures, as well appurtenances, appurtenances, such as exterior flatwork adjacent to the such as exterior flatwork adjacent to the There are risks associated with There are risks associated with supportingsupporting pavements over expansive soils without soil modification. However, the modification. However, the costscosts associated with remediating pavement subgrades for associated with remediating pavement subgrades for expansive soils are generally considered costexpansive soils are generally considered cost recommendation for pavement subgraderecommendation for pavement subgrade willing to accept some risk of poor pavement performance as a result of postwilling to accept some risk of poor pavement performance as a result of post vertical movements associated with the high swell potential of the overburden soils. vertical movements associated with the high swell potential of the overburden soils. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 11 specific to the site conditions encountered may be provided at the time of construction. The project budget should include additional cost associated with the removal and replacement of additional fill material. Subgrade materials that are disturbed during grading should be moisture conditioned and re-compacted according to the recommendations provided in this report. 9.1.3 Re-Use of Site Soils The onsite soils encountered during our subsurface exploration consisted of loam and alluvium. Laboratory testing indicates the onsite soils have high swell potential at low confinement pressures (near surface soils) at their in-situ moisture contents. Soils generated from on-site excavation activities in the loam and alluvium deposits that are free of deleterious materials and organic matter, do not contain particles larger than 3 inches in diameter, can generally be used as engineered fill as evaluated by the geotechnical consultant provided they are compacted and moisture conditioned as recommended in this report. Fragments of rock, cobbles, and inert construction debris (e.g., concrete or asphalt) larger than 3 inches in diameter may be incorporated into the project fills in non-structural areas and below the anticipated utility installation depths. A Geotechnical Engineer should be consulted regarding appropriate recommendations for usage of such materials on a case- by-case basis when such materials have been observed during earthwork. Care should be taken to avoid nesting of oversized materials during placement. Recommendations provided in Section 203 of the current CDOT Standard Specifications for Road and Bridge Construction should be followed during the placement of oversized material. 9.1.4 Fill Placement and Compaction Fine-grained soils (on-site soils that classify as CL or CH) used as engineered fill should be moisture-conditioned to moisture contents between optimum moisture content and 3 percent over optimum moisture content. Granular soils (on-site soils that classify as SC, SW, SP-SC, or import soils) used as engineered fill should be moisture-conditioned to moisture contents within 2 percent of optimum moisture content. Engineered fill should be placed in uniform horizontal lifts. Engineered fill should be compacted to a relative compaction of 95 percent, or more, as evaluated by the American Society for Testing and Materials (ASTM) D698. The engineered fill should be compacted by appropriate mechanical methods. Lift thickness for fill will be dependent upon the type of compaction equipment utilized. Backfill should be of deleterious materials and organic matter, do not contain particles larger than 3 inches in of deleterious materials and organic matter, do not contain particles larger than 3 inches in diameter, can generally be used as engineered fill as evaluated by the geotechnical diameter, can generally be used as engineered fill as evaluated by the geotechnical consultant provided they are compacted and moisture conditionedconsultant provided they are compacted and moisture conditioned as recommended in this Fragments of rock, cobbles, and inert construction debris (e.g., concrete or asphalt) larger Fragments of rock, cobbles, and inert construction debris (e.g., concrete or asphalt) larger than 3 inches in diameter may be incorporated into the project fills in nonthan 3 inches in diameter may be incorporated into the project fills in non and below the anticipated utility installation depths. A Geotechnical Engineer should be and below the anticipated utility installation depths. A Geotechnical Engineer should be appropriate recommendations for usage of such materials on a caseappropriate recommendations for usage of such materials on a case case basis when such materials have case basis when such materials have beenbeen taken to avoid nesting of oversized materials during placement. Recommendations taken to avoid nesting of oversized materials during placement. Recommendations provided in Section 203 of the current CDOT Standard Specifications for Road and Bridge provided in Section 203 of the current CDOT Standard Specifications for Road and Bridge Construction should be followed during the placement of oversized material. Construction should be followed during the placement of oversized material. Fill Placement and Fill Placement and Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 12 placed in lifts not exceeding 8 inches in loose thickness in areas compacted by other-than hand operated machines. Backfill should be placed in lifts not exceeding 6 inches in loose thickness in areas compacted by hand operated machines. Fill materials should not be placed, worked, rolled while they are frozen, thawing, or during poor/inclement weather conditions. Compaction areas should be kept separate, and no lift should be covered by another until relative compaction and moisture content within the recommended ranges are obtained. Use of controlled low-strength material (CLSM) should be considered in lieu of compacted fill for areas with low tolerances for surface settlements, for excavations that extend below the groundwater table and in areas with difficult access for compaction equipment. CLSM should be placed in lifts of 5 feet or less with a 24-hour or more curing period between each lift. 9.1.5 Imported Soil Imported soil to be used as engineered fill should be free of organic material and other deleterious materials should consist of relatively impervious material with a very low to low expansion potential (less than 1 percent against a surcharge pressure of 500 psf when remolded at optimum moisture content). Imported fill should have less than 50 percent passing the No. 200 Sieve and should have a plasticity index that is between 10 and 20. Import soil in contact with ferrous metals should have low corrosion potential. Import material in contact with concrete should have a soluble sulfate content less than 0.1 percent. We further recommend that proposed import soils be evaluated by the project’s geotechnical consultant at the borrow source for its suitability prior to importation to the project site. Import soil should be moisture-conditioned and placed and compacted in accordance with the recommendations set forth in Section 9.1.4. 9.1.6 Controlled Low Strength Material Use of CLSM should be considered in lieu of compacted fill for areas with low tolerances for surface settlements, for excavations that extend below the groundwater table and in areas with difficult access for compaction equipment. CLSM consists of a fluid, workable mixture of aggregate, Portland cement, and water. CLSM should be placed in lifts of 5 feet or less with a 24-hour or more curing period between each lift. in areas with difficult access for compaction equipment. CLSM in areas with difficult access for compaction equipment. CLSM hour or more curing period between each hour or more curing period between each Imported soil to be used as engineered fill should be free of organic material and other Imported soil to be used as engineered fill should be free of organic material and other deleterious materials should consist of relatively impervious material with a very low to low deleterious materials should consist of relatively impervious material with a very low to low 1 1 percent against a surcharge pressure of percent against a surcharge pressure of remolded at optimum moisture content). Imported fill should have less than 50 percent remolded at optimum moisture content). Imported fill should have less than 50 percent passing the No. 200 Sieve and should have a plasticity index that is between 10 and 20. passing the No. 200 Sieve and should have a plasticity index that is between 10 and 20. Import soil in contact with ferrous metals should have low corrosion potential. Import Import soil in contact with ferrous metals should have low corrosion potential. Import material in contact with concrete should have a soluble sulfate content less than material in contact with concrete should have a soluble sulfate content less than Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 13 The use of CLSM has several advantages: A narrower excavation can be used where shoring is present, thereby minimizing the quantity of soil to be excavated and possibly reducing disturbance to the near-by traffic; Compaction requirements do not apply; There is less risk of damage to improvements, since little compaction is needed to place CLSM; CLSM can be batched to flow into irregularities in excavation bottoms and walls; and The number of workers needed inside the trench excavation is reduced. The CLSM mix design should be submitted for review prior to placement. The 28-day strength of the material should be no less than 50 pounds per square inch (psi) and no more than 150 psi. CLSM should be observed and tested by the geotechnical consultant. 9.1.7 Utility Installation The contractor should take particular care to achieve and maintain adequate compaction of the backfill soils around manholes, valve risers and other vertical pipeline elements where settlements are commonly observed. Use of CLSM or a similar material should be considered in lieu of compacted soil backfill in areas with low tolerances for surface settlement. This would also reduce the permeability of the utility trenches. Pipe bedding materials, placement and compaction should meet the specifications of the pipe manufacturer and applicable municipal standards. Materials proposed for use as pipe bedding should be tested for suitability prior to use. Special care should be exercised to avoid damaging the pipe or other structures during the compaction of the backfill. In addition, the underside (or haunches) of the buried pipe should be supported on bedding material that is compacted as described above. This may need to be performed with placement by hand or small-scale compaction equipment. Surface drainage should be designed to divert the surface water away from utility trench alignments. Where topography, site constraints or other factors limit or preclude adequate surface drainage, the granular bedding materials should be surrounded by a non-woven geotextile fabric (e.g., TenCate Mirafi® 140N or the equivalent) to reduce the migration of fines into the bedding which can result in severe, isolated settlements. Development of site grading plans should consider the subsurface transfer of water in utility trenches and the pipe bedding. Sandy pipe bedding materials can function as efficient strength of the material should be no less than 50 pounds per square inch (psi) and no strength of the material should be no less than 50 pounds per square inch (psi) and no by the geotechnical consultant.by the geotechnical consultant. The contractor should take particular care to achieve and maintain adequate compaction of The contractor should take particular care to achieve and maintain adequate compaction of risers and other vertical pipeline elements where risers and other vertical pipeline elements where settlements are commonly observed. Use of CLSM or a settlements are commonly observed. Use of CLSM or a considered in lieu of compacted soil backfill in areas with low tolerances for surface considered in lieu of compacted soil backfill in areas with low tolerances for surface settlement. This would also reduce the permeability of the utility trenches. settlement. This would also reduce the permeability of the utility trenches. Pipe bedding materials, placemenPipe bedding materials, placement and compaction should t and compaction should pipe manufacturer and applicable pipe manufacturer and applicable municipalmunicipal bedding should be tested for suitability prior to use. bedding should be tested for suitability prior to use. Special care should be exercised to avoid Special care should be exercised to avoid compaction of the backfill. In addition, the underside (or haunches) of the buried pipe compaction of the backfill. In addition, the underside (or haunches) of the buried pipe Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 14 conduits for re-distribution of natural and applied waters in the subsurface. Cut-off walls in utility trenches or other water-stopping measures should be implemented to reduce the rates and volumes of water transmitted along utility alignments and toward buildings, pavements and other structures where excessive wetting of the underlying soils will be damaging. Incorporation of water cut-offs and/or outlet mechanisms for saturated bedding materials into development plans could be beneficial to the project. These measures also will reduce the risk of loss of fine-grained backfill soils into the bedding material with resultant surface settlement. 9.1.8 Temporary Cut Slopes Temporary excavations will be needed for this project to construct utilities. Based on the subsurface information obtained from our exploratory excavations and our experience with similar projects, we anticipate that the soil conditions and stability of the excavation sidewalls may vary with depth. Soils with higher fines content may stand vertically for a short time (less than 12 hours) with little sloughing. However, as the soil dries after excavation or as the excavations are exposed to rainfall, sloughing may occur. Soils with low cohesion (e.g., predominately sandy or gravelly material), may slough or cave during excavation, especially if wet or saturated. The contractor should provide safely sloped excavations or an adequately constructed and braced shoring system, in compliance with OSHA regulations as mentioned in Section 9.1.1. In our opinion, the site soils should generally be considered a Type C soil when applying the OSHA regulations. For these soil conditions, OSHA recommends a temporary slope inclination of 1.5H:1V or flatter for excavations 20 feet or less in depth. Appropriate slope inclinations should be evaluated in the field by an OSHA-qualified “Competent Person” based on the conditions encountered. 9.2 Spread Footing Foundations Perimeter footings should extend to 36 inches or more below the lowest exterior finished grade (for frost protection), and bear on 12 or more inches of moisture-conditioned and compacted engineered fill as described in Section 9.1.2 of this report. Continuous wall footings should have a width of 18 inches or more and column footings should have a width of 24 inches or more. Footings should be reinforced in accordance with the recommendations of the Structural Engineer. our exploratory excavations and our experience with our exploratory excavations and our experience with similar projects, we anticipate that the soil conditions and stability of the excavation similar projects, we anticipate that the soil conditions and stability of the excavation sidewalls may vary with depth. Soils with higher fines content may stand vertically for a sidewalls may vary with depth. Soils with higher fines content may stand vertically for a short time (less than 12 hours) with little sloughing. However, as the soil dries after short time (less than 12 hours) with little sloughing. However, as the soil dries after excavation or as the excavations are exposed to rainfall, sloughing may occur. Soils with excavation or as the excavations are exposed to rainfall, sloughing may occur. Soils with low cohesion (e.g., predominately sandy or gravelly material), may slough or cave during low cohesion (e.g., predominately sandy or gravelly material), may slough or cave during excavation, especially if wet or saturated.excavation, especially if wet or saturated. The contractor should provide safely The contractor should provide safely slopedsloped excavations or an adequately constructed and excavations or an adequately constructed and braced shoring system, in compliance with OSHA braced shoring system, in compliance with OSHA In our opinion, the site soils should generally be In our opinion, the site soils should generally be the OSHA regulations. For these soil conditiothe OSHA regulations. For these soil conditio H:1V or flatter for excavations 20 feet or less in depth. Appropriate slope H:1V or flatter for excavations 20 feet or less in depth. Appropriate slope Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 15 Footings may be designed using an allowable bearing pressure of 2,500 pounds psf for static conditions. The bearing capacity may be increased by one-third when considering loads of short duration such as wind or seismic forces. The foundations should preferably be proportioned such that the resultant force from design loads, including lateral loads, falls within the kern (i.e., middle one-third of the footing base). Uplift resistance can be developed from the weight of the footings, the effective weight of any overlying soil, and the weight of the supported structure itself. The effective unit weight of the soil can be assumed to be 120 pcf. Soil uplift resistance may be calculated as the weight of the soil prism defined by a diagonal line extending from the perimeter of the foundation to the ground surface at an angle equal to 20 degrees from the vertical. Under large moment and/or shear loading, the effective size of the uplift soil prism may be reduced. An appropriate safety factor should be applied. The bottom surface of foundation excavations should be compacted with hand-held dynamic compaction equipment (i.e., jumping jack, flat-plate vibrator) prior to placement of forms and reinforcing steel. The base of foundation excavations should be free of water and loose soil prior to placing concrete. Concrete should be placed soon after subgrade compaction to reduce bearing soil disturbance. Should the soils at bearing level become excessively dry, disturbed, or saturated, the affected soil should be moisture conditioned and compacted. It is recommended that Ninyo & Moore be retained to observe, test, and evaluate the soil foundation bearing materials. Based on the results of our subsurface exploration and laboratory testing, and provided our grading recommendations provided in Section 9.1 are followed, we estimate total and differential settlement of approximately 1-inch and 1/2-inch, respectively. Distortions of approximately 1-inch (vertical) over 50 feet (horizontal) are possible due the swell potential of the on-site soils. 9.3 Slab-On-Grade Floors The buildings may be provided with slab-on-grade floors bearing 3 or more feet of moisture conditioned and compacted engineered fill as described in Section 9.1.2 of this report. For slab design, a design modulus of subgrade reaction (K) of 150 pounds per square inch per inch of deflection (pci) may be used for the subgrade soils in evaluating such deflections. This value is based on a unit square foot area and can be adjusted for large slabs. Adjusted values shear loading, the effective size of the uplift soil prism may be reduced. An appropriate safety shear loading, the effective size of the uplift soil prism may be reduced. An appropriate safety face of foundation excavations should be compacted with handface of foundation excavations should be compacted with hand plate vibrator) prior to placement of forms and plate vibrator) prior to placement of forms and reinforcing steel. The base of foundation excavations should be free of water and loosereinforcing steel. The base of foundation excavations should be free of water and loose to placing concrete. Concrete should be placed soon after subgrade compaction to reduce to placing concrete. Concrete should be placed soon after subgrade compaction to reduce bearing soil disturbance. Should the soils at bearing level become excessively dry, disturbed, or bearing soil disturbance. Should the soils at bearing level become excessively dry, disturbed, or saturated, the affected soil should be moisture conditioned and compacted. It is recommended saturated, the affected soil should be moisture conditioned and compacted. It is recommended that Ninyo & Moore be retained to observe, test, and evaluate the soil foundation bearing that Ninyo & Moore be retained to observe, test, and evaluate the soil foundation bearing Based on the results of our subsurface exploration and laboratory testing, and provided our Based on the results of our subsurface exploration and laboratory testing, and provided our ndations provided in Section 9.1ndations provided in Section 9.1 differential settlement of approximately 1differential settlement of approximately 1 inch (vertical) over inch (vertical) over Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 16 of the modulus of subgrade reaction, Kv, can be obtained from the following equation for slabs of various widths: Kv = K[(B+1)/2B]2 (pci) B in the above equation represents the width of the slab in feet between line loads/point loads. The design of the floor slabs (including jointing and reinforcement) is the responsibility of the Structural Engineer. Joints should be constructed at intervals designed by the Structural Engineer to help reduce random cracking of the slab. Floor slabs should be adequately reinforced. Recommendations based on structural considerations for slab thickness, jointing, and steel reinforcement should be developed by the Structural Engineer in accordance with American Concrete Institute recommendations. Proper placement of reinforcement in the slab is vital for satisfactory performance. The slab should be constructed so that it “floats” independent of the foundations. Floor slabs should be separated from bearing walls and columns with expansion joints, which allow unrestrained vertical movement. Joints should be observed periodically, particularly during the first several years after construction. Slab movement can cause previously free-slipping joints to bind. Measures should be taken so that slab isolation is maintained in order to reduce the likelihood of damage to walls and other interior improvements. If post-construction vertical slab movement of approximately 1 inch cannot be tolerated or desired, then we recommend utilizing a structural floor system spanning over a void or a crawl space. Interior partitions resting on floor slabs should be provided with slip joints so that if the slabs move, the movement cannot be transmitted to the upper structure, including wallboards and door frames. A slip joint that allows 2 or more inches of vertical movement is recommended for placement at the bottoms of the interior partitions. If slip joints are placed at the tops of walls, in the event that the floor slabs move, it is expected that the wall will show signs of distress, especially where the floors meet the exterior wall. Interior plumbing lines that penetrate interior partition walls, where the slip joints are placed at the top of the walls, should be provided with flexible connections that can handle 2 or more inches of vertical movement. The need for a moisture retarding and/or vapor retarding system should be considered by the Structural Engineer or Architect, based on the moisture sensitivity of the anticipated flooring. The placement of a vapor retarder is recommended in areas where moisture-sensitive floor coverings are anticipated. and steel reinforcement should be developed by the Structural Engineer in accordance with and steel reinforcement should be developed by the Structural Engineer in accordance with American Concrete Institute recommendations. Proper placement of reinforcement in the slab American Concrete Institute recommendations. Proper placement of reinforcement in the slab independent of the foundations. independent of the foundations. should be separated from bearing walls and columns with expansion joints, which allow should be separated from bearing walls and columns with expansion joints, which allow nts should be observed periodically, particularly during the nts should be observed periodically, particularly during the first several years after construction. Slab movement can cause previously freefirst several years after construction. Slab movement can cause previously free bind. Measures should be taken so that slab isolation is maintained in order to reduce the bind. Measures should be taken so that slab isolation is maintained in order to reduce the ihood of damage to walls and other interior improvements. If postihood of damage to walls and other interior improvements. If post movement of approximately 1 inch cannot be tolerated or desired, then we recommend utilizing inch cannot be tolerated or desired, then we recommend utilizing a structural floor system spanning over a void or a crawl space. a structural floor system spanning over a void or a crawl space. rior partitions resting on floor slabs should be provided with slip joints so that if the slabs rior partitions resting on floor slabs should be provided with slip joints so that if the slabs move, the movement cannot be transmitted to the upper structure, including wallboards and move, the movement cannot be transmitted to the upper structure, including wallboards and door frames. A slip joint that allows door frames. A slip joint that allows Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 17 9.4 Earth Pressures and Below-Grade Walls Earth pressures are used to compute the lateral forces acting on below-grade walls. These pressures can be classified as at-rest, active, and passive. The direction and magnitude of the soil/wall movement just before failure affects the resulting pressure condition. At-rest conditions exist when there is no movement, such as for a restrained wall. Active stresses are exerted when the wall moves out and the soil moves toward the wall away from the soil mass, thereby mobilizing the shear strength of the soil. Passive stresses exist when the wall moves toward the soil mass. The recommended equivalent fluid pressures in Table 3 assume moisture-conditioned and compacted engineered fill with an angle of internal friction () of 26 degrees and a unit weight of 120 pcf. The values listed below are for static conditions. Table 3 – Lateral Earth Pressures Soil Condition Active Pressure (pcf) At-rest Pressure (pcf) Passive Pressure (pcf) Engineered Fill 47 67 307 The use of heavy compaction equipment adjacent to below-grade walls could result in lateral earth pressures well in excess of those predicted in Table 3. We recommend that the upper 24 inches of soil that is not protected by pavement or a concrete slab, be neglected when calculating passive resistance. This zone, where applicable, should be backfilled with cohesive soils to minimize infiltration of surface water into the backfill. For frictional resistance to lateral loads, we recommend that an ultimate coefficient of friction of 0.35 be used between soil and concrete. To limit long-term hydrostatic pressure behind the wall, we recommend measures, such as placement of sealants, be taken such that surface water is not allowed to penetrate between the loading dock walls and exterior slabs. 9.5 Pavements We understand project pavements will be privately maintained. Pavement section alternatives are included herein for the paved surfaces, which include standard duty automobile parking areas and driveways, and heavy duty drive lanes and fire lanes. The pavement sections recommended below were developed in general accordance with the guidelines and procedures of the American Association of State Highway and Transportation At rest Pressure (pcf) The use of heavy compaction equipment adjacent to The use of heavy compaction equipment adjacent to belowbelow earth pressures well in excess of those predicted in Table earth pressures well in excess of those predicted in Table inches of soil that is not protected by pavementinches of soil that is not protected by pavement calculating passive resistance. This zone, where applicable, should be backfilled with cohesive calculating passive resistance. This zone, where applicable, should be backfilled with cohesive soils to minimize infiltration of surface water into the backfill. For frictional resistance to laterasoils to minimize infiltration of surface water into the backfill. For frictional resistance to latera loads, we recommend that an ultimate coefficient of friction of 0.35 be used between soil and loads, we recommend that an ultimate coefficient of friction of 0.35 be used between soil and Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 18 Officials (AASHTO), (AASHTO, 1993), CDOT, and Larimer County. Table 4 summarizes the minimum pavement sections for asphaltic concrete (AC) pavements and Portland cement concrete pavements (PCCP). Pavement sections may be modified once more detailed information regarding traffic volumes and vehicle usage is available for review. 9.5.1 Pavement Design Specific traffic loadings for the project were not available at the time of this report preparation. Based on our experience with similar commercial facilities, an equivalent 18- kip single axle load value of 36,500 was assumed for standard-duty automobile parking areas and 365,000 was assumed for heavy-duty drive lanes and loading areas for 20-year design lives, respectively. If design traffic loadings differ significantly from this assumed value, we should be notified to re-evaluate the pavement recommendations below. The current subgrade soils encountered in our borings typically consisted of lean clay to fat clay with varying amounts of sand and gravel that classify as A-6 and A-7 soils in accordance with the AASHTO classification system. It is anticipated that fill imported to the site will classify as A-6 or better. We utilized a design R-Value of 5 for the pavement subgrade soils for the project. The design of flexible pavements was based on the following input parameters: Initial Serviceability: 4.5 Terminal Serviceability: 2.0 Reliability 80% Overall Standard Deviation: 0.44 Resilient Modulus (untreated): 3,025 psi (R-Value of 5) Stage Construction: 1.0 The design of rigid pavements was based on the following input parameters: Initial Serviceability: 4.5 Terminal Serviceability: 2.0 Reliability 80% 28-Day Mean PCC Modulus Rupture: 650 psi 28-Day Mean Modulus of Elasticity: 3.6 x 10 6 psi Mean Effective k value: 100 psi/in Overall Standard Deviation: 0.34 Load Transfer Coefficient: 4.2 Overall Drainage Coefficient: 1.0 evaluate the pavement recommendations below.evaluate the pavement recommendations below. The current subgrade soils encountered in our borings typically consisted of lean The current subgrade soils encountered in our borings typically consisted of lean and gravel and gravel that classify as Athat classify as A classification system. It is anticipated that fill imported to the classification system. It is anticipated that fill imported to the 6 or better. We utilized a design R6 or better. We utilized a design R-Value of 5 for the The design of flexible pavements was basedThe design of flexible pavements was based on the following on the following Terminal Serviceability:Terminal Serviceability: Overall Standard Deviation:Overall Standard Deviation: (untreated)(untreated): : Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 19 Based on the above-mentioned guidelines, procedures, and input parameters, Table 4 provides our recommended pavement section thicknesses for pavements supported on 2 or more feet of moisture conditioned and compacted engineered fill (overexcavated and recompacted in-situ deposits). Table 4 – Recommended Pavement Thickness Traffic Type Full Depth AC (inches) Composite AC / ABC (inches) PCCP (inches) Standard-Duty Areas 6.0 4.0 / 6.0 5.0 Heavy-Duty Areas 8.0 6.0 / 8.0 6.0 Notes:AC = Asphalt Concrete, ABC = Aggregate Base Course, PCCP = Portland Cement Concrete Pavement We recommend PCCP be utilized in entrance and exit sections, dumpster pads, loading areas, or other areas where extensive wheel maneuvering are expected. The dumpster pad should be large enough to support the wheels of the truck, which will bear the load of the dumpster. Although the use of ABC is not integral for structural support in PCCP pavements, the placement of 4 or more inches of ABC below PCCP pavements will develop a more stable subgrade for concrete truck traffic associated with the pavement construction and help reduce potential slab curl, shrinkage cracking, and subgrade “pumping” through joints. Adequate joint spacing and reinforcement is recommended to prevent loss of load transfer across saw-cut crack control joints. Joints should be sealed to reduce water infiltration. The design guidelines provided in the referenced ACI 330R-01 guide should be followed for joint spacing and reinforcing. Where practical, we recommend “early-entry” cutting of crack-control joints in PCCP. Cutting of PCCP in its ‘green” state typically reduces the potential for micro-cracking of the pavements prior to the crack control joints being formed, compared to cutting the joints after the concrete has fully set. Micro-cracking of pavements may lead to crack formation in locations other than the sawed joints, and/or reduction of fatigue life of the pavement. Ninyo & Moore has observed dishing in some AC parking lots. Dishing is observed in frequently-used parking stalls (such as near the front of buildings), and occurs under the wheel footprint in these stalls. The use of higher-grade AC, or surfacing these areas with PCCP, could be considered. The dishing is exacerbated by factors such as irrigated islands or planter areas, and sheet surface drainage to the front of structures. PCCP be utilized in entrance and exit sections, dumpster pads, loadPCCP be utilized in entrance and exit sections, dumpster pads, load areas, or other areas where extensive wheel maneuvering are expected. The dumpster pad areas, or other areas where extensive wheel maneuvering are expected. The dumpster pad should be large enough to support the wheels of the truck, should be large enough to support the wheels of the truck, whichwhich will bear the load of the will bear the load of the Although the use of ABC is not integral for structural Although the use of ABC is not integral for structural support support placement of 4 or more inches of ABC below PCCP pavementsplacement of 4 or more inches of ABC below PCCP pavements subgrade for concrete truck traffic associated with the pavement construction and help subgrade for concrete truck traffic associated with the pavement construction and help reduce potential slab curl, shrinkage cracking, and subgrade reduce potential slab curl, shrinkage cracking, and subgrade Adequate joint spacing and reinforcement is recommended to prevent loss of load transfer Adequate joint spacing and reinforcement is recommended to prevent loss of load transfer cut crack control joints. Joints should be sealed to reduce water infiltration. The cut crack control joints. Joints should be sealed to reduce water infiltration. The design guidelines provided in the referenceddesign guidelines provided in the referenced spacing and reinforcing. spacing and reinforcing. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 20 If AC pavements are utilized in the trailer parking areas, dishing of the AC pavements should be anticipated where trailer dollies are in contact with the AC surface due to the concentrated loads which occur at the trailer dollies. As a result, we recommend a PCCP dolly pad be constructed within the heavy-duty AC areas. The dolly pad should have a width of 5 feet or more. Reinforcing and joint spacing should be designed by the project structural engineer. 9.5.2 Dolly Pads If trailer parking is desired in the heavy-duty AC areas, dishing of the AC areas should be anticipated where trailer dollies are in contact with the AC surface due to the concentrated loads which occur at the trailer dollies. As a result, we recommend a PCCP dolly pad be constructed within the heavy-duty AC areas if trailing parking is desired in these areas. The dolly pad should be constructed on both the shipping and receiving pavements and should have a width of 5 feet or more. Reinforcing and joint spacing should be designed by the project structural engineer. 9.5.3 Pavement Subgrade Preparation Due to the measured swell potential of the subgrade fill materials, we recommend pavements are placed on a zone of moisture-conditioned and compacted fill extending 24 or more inches below the bottom of the pavement section or flatwork as discussed above in Section 9.1.2. As an alternative, the pavements can be placed on a zone of 12 or more inches of CTS using fly ash, lime, or Portland cement to reduce plasticity, reduce swell- potential, and increase strength of the treated subgrade soils. The contractor should be prepared either to dry the subgrade materials or moisten them, as needed, prior to compaction. Some site soils may pump or deflect during compaction if moisture levels are not carefully monitored. The contractor should be prepared to process and compact such soils to establish a stable platform for paving, including use of chemical stabilization or geotextiles, where needed. The prepared subgrade should be protected from the elements prior to pavement placement. Subgrades that are exposed to the elements may need additional moisture conditioning and compaction, prior to pavement placements. Immediately prior to paving, the subgrade should be proofrolled with a heavily loaded, pneumatic tired vehicle and checked for moisture. Areas that show excessive deflection during proof rolling should be excavated and replaced and/or stabilized. Areas allowed to pond prior to paving may need to be re-worked prior to proofrolling. if trailing parking is desired in these areasif trailing parking is desired in these areas dolly pad should be constructed on both the shipping and receiving pavements and should dolly pad should be constructed on both the shipping and receiving pavements and should have a width of 5 feet or more. Reinforcing and joint spacing should be designed by the have a width of 5 feet or more. Reinforcing and joint spacing should be designed by the Pavement Subgrade PreparationPavement Subgrade Preparation Due to the measured swell potential of the subgrade fill materials, we recommend Due to the measured swell potential of the subgrade fill materials, we recommend pavements are placed on a zone of moisturepavements are placed on a zone of moisture--conditioned and compacted fill extending 24 conditioned and compacted fill extending 24 or more inches below the bottom of the pavement or more inches below the bottom of the pavement s an alternative, the pavements can be placed on a zone ofs an alternative, the pavements can be placed on a zone of using fly ashusing fly ash, limelime, or Portland cement, or Portland cement potential, and increase strength of the treated subgrade soils. potential, and increase strength of the treated subgrade soils. The contractor should be prepareThe contractor should be prepare needed, prior to compaction. Some site soils may pump or deflect during compaction if needed, prior to compaction. Some site soils may pump or deflect during compaction if Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 21 It should be noted that the subgrade recommendations included in this report are provided based on the owner accepting some risk of poor pavement performance due to the on-site swelling soils. The measures recommended above are intended to minimize this risk. Additional recommendations could be provided to further reduce this risk. 9.5.4 Pavement Materials The AC pavement shall consist of a bituminous plant mix composed of a mixture of high quality aggregate and bituminous material, which meets the requirements of a job-mix formula established by a qualified engineer. The asphalt material used should be based on a SuperPave Gyratory Design Revolution of 75. Lower lifts should be constructed using an asphalt mix Grading S and asphalt cement binder grade PG 58-28. The top lift should be constructed using an asphalt mix Grading SX and asphalt cement binder grade PG 64-22. Pavement layer thickness should be between 2 and 3 inches for the lower lifts and 2 to 2.5 inches for the top lift. The geotechnical engineer should be retained to review the proposed pavement mix designs, grading, and lift thicknesses prior to construction. PCCP should consist of a plant mix composed of a mixture of aggregate, Portland cement and appropriate admixtures meeting the requirements of Larimer County. Concrete should have a modulus of rupture of third point loading of 650 psi or more. The concrete should be air-entrained with approximately 6 percent air and should have a cement content of six or more sacks per cubic yard. Allowable slump should be approximately 4 inches. Thickened edges should be used along outside edges of PCCP. The edge thickness should be 2 inches or more than the recommended PCCP thickness and taper to the recommended PCCP thickness 36 inches inward from the edge. Integral curbs may be used in lieu of thickened edges. PCCP should have longitudinal and transverse joints that meet the applicable requirements of Larimer County. 9.5.5 Pavement Maintenance The collection and diversion of surface drainage away from paved areas is vital to satisfactory performance of the pavements. The subsurface and surface drainage systems should be carefully designed to facilitate removal of the water from paved areas and subgrade soils. Allowing surface waters to pond on pavements will cause premature pavement deterioration. Where topography, site constraints or other factors limit or preclude adequate surface drainage, pavements should be provided with edge drains to reduce loss constructed using an asphalt mix Grading SX and asphalt cement binder grade constructed using an asphalt mix Grading SX and asphalt cement binder grade Pavement layer thickness should be between 2 and 3 inches for the lower lifts and 2 to 2.5 Pavement layer thickness should be between 2 and 3 inches for the lower lifts and 2 to 2.5 inches for the top lift. The geotechnical engineer should be retained to review the proposed inches for the top lift. The geotechnical engineer should be retained to review the proposed pavement mix designs, grading, and lift thicknesses prior to copavement mix designs, grading, and lift thicknesses prior to construction. nstruction. should consist of a plant mix composed of a mixture of aggregate, Portland should consist of a plant mix composed of a mixture of aggregate, Portland meeting the requirements ofmeeting the requirements of Larimer County. Concrete should have a modulus of rupture of third point loading of 650 psi or more. The concrete should be have a modulus of rupture of third point loading of 650 psi or more. The concrete should be entrained with approximately 6 percent air and should have a cement content of six or entrained with approximately 6 percent air and should have a cement content of six or more sacks per cubic yard. Allowable slump should be approximately 4 inches. more sacks per cubic yard. Allowable slump should be approximately 4 inches. Thickened edges should be used along outside edges of PCCP. The edge thickness Thickened edges should be used along outside edges of PCCP. The edge thickness should be 2 inches or more than the recommended PCCP thickness and taper to the should be 2 inches or more than the recommended PCCP thickness and taper to the recommended PCCP thickness 36 inches inward from the edge. Integral curbs may be recommended PCCP thickness 36 inches inward from the edge. Integral curbs may be used in lieu of thickened edges.used in lieu of thickened edges. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 22 of subgrade support. The long-term performance of the pavement also can be improved greatly by backfilling and compaction behind curbs, gutters, and sidewalks so that ponding is not permitted and water infiltration is reduced. Landscape irrigation in planters adjacent to pavements and in “island” planters within paved areas should be carefully monitored or differential heave and/or rutting of the nearby pavements will result. Drip irrigation systems are recommended for such planters to reduce over-spray and water infiltration beyond the planters. We recommend edge drains where the profile/slopes are less than 1 percent. The standard care of practice in pavement design describes the recommended flexible pavement section as a “20-year” design pavement; however, many pavements will not remain in satisfactory condition without routine, preventive maintenance and rehabilitation procedures performed during the life of the pavement. Preventive pavement treatments are surface rehabilitation and operations applied to improve or extend the functional life of a pavement. These treatments preserve, rather than improve, the structural capacity of the pavement structure. In the event the existing pavement is not structurally sound, the preventive maintenance will have no long-lasting effect. Therefore, a routine maintenance program to seal joints and cracks, and repair distressed areas is recommended. 9.6 Concrete Flatwork Ground-supported flatwork, such as walkways, will be subject to soil-related movements resulting from heave/settlement, frost, etc. Thus, where these types of elements abut rigid building foundations or isolated/suspended structures, differential movements should be anticipated. We recommend that flexible joints be provided where such elements abut the main structure to allow for differential movement at these locations. We recommend that exterior concrete flatwork and the target structures be supported on improved subgrade as described in Section 9.1.2 of this report. Positive drainage should be established and maintained adjacent to flatwork. Water should not be allowed to pond on flatwork. In no case should exterior flatwork extend under any portion of the building where there is less than 2 inches of clearance between the flatwork and any element of the building. Exterior flatwork in contact with brick, rock facades, or any other element of the building can cause damage to the structure if the flatwork experiences movements. design pavement; however, many pavements will not design pavement; however, many pavements will not remain in satisfactory condition without routine, preventive maintenance and rehabilitation remain in satisfactory condition without routine, preventive maintenance and rehabilitation procedures performed during the life of the pavement. Preventive pavement treatments are procedures performed during the life of the pavement. Preventive pavement treatments are surface rehabilitation and operations applied to improve or extend the functional life of a surface rehabilitation and operations applied to improve or extend the functional life of a pavement. These treatments preserve, rather than improve, the structural capacity of the pavement. These treatments preserve, rather than improve, the structural capacity of the pavement structure. In the event the existing pavement is not structurally sound, the pavement structure. In the event the existing pavement is not structurally sound, the preventive maintenance will have no longpreventive maintenance will have no long--lasting effect. Therefore, a routine maintenance lasting effect. Therefore, a routine maintenance program to seal joints and cracks, and repair distressed areas is recommended. program to seal joints and cracks, and repair distressed areas is recommended. flatwork, such as walkways, will be subject to soilflatwork, such as walkways, will be subject to soil resulting from heave/settlement, frost, etc. Thus, where these types of elements abut rigid resulting from heave/settlement, frost, etc. Thus, where these types of elements abut rigid building foundations or isolated/suspended structures, differential movements should be building foundations or isolated/suspended structures, differential movements should be ipated. We recommend that flexible joints be provided where such elements abut the main ipated. We recommend that flexible joints be provided where such elements abut the main structure to allow for differential movement at these locations. structure to allow for differential movement at these locations. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 23 The ground-supported flatwork should be provided with crack-control and expansion joints in accordance with Larimer County Specifications. 9.7 Corrosion Considerations The corrosion potential of on-site soils to concrete and buried metal was evaluated in the laboratory using selected samples obtained from the exploratory borings. Laboratory testing was performed to assess the effects of sulfate on concrete and the effects of soil resistivity on buried metal. Results of these tests are presented in Appendix B. Recommendations regarding concrete to be utilized in construction of proposed improvements and for buried metal pipes are provided in the following sections. 9.7.1 Concrete The test for water-soluble sulfate content of the soils was performed using CDOT Test Method CP-L 2104. The laboratory test results are presented in Appendix B. The percentage of water-soluble sulfates in water measured was 0.025 percent, corresponding to 250 parts per million, respectively. Based on Table 601-2 of the CDOT 2011 Standard Specifications for Road and Bridge Construction, the on-site soils represent a Class 1 severity of sulfate exposure to concrete on a scale that ranges between Class 0 and Class 3. Therefore, we recommend that the concrete used for this project should have a maximum water to cementitious material ratio of 0.45 and the cementitious materials should meet one of the below outlined requirements. ASTM C 150 Type II or V; Class C fly ash shall not be substituted for cement. ASTM C 595 Type IP(MS) or IP(HS); Class C fly ash shall not be substituted for cement. ASTM C 1157 Type MS or HS; Class C fly ash shall not be substituted for cement. When ASTM C 150 Type III cement is allowed, as in Class E concrete, it shall have no more than 8 percent C3A. Class C fly ash shall not be substituted for cement. The Structural Engineer should ultimately select the concrete design strength based on the project specific loading conditions. However, higher strength concrete may be selected for increased durability, resistance to slab curling and shrinkage cracking. We recommend the use of concrete with a design 28-day compressive strength of 4,000 psi or more, for concrete slabs at this site. Concrete exposed to the elements should be air-entrained. soluble sulfate content of the soils was performed using CDOT Tsoluble sulfate content of the soils was performed using CDOT T L 2104. The laboratory test results are presented in AppendixL 2104. The laboratory test results are presented in Appendix soluble sulfates in water measured was soluble sulfates in water measured was 0.020.025 5 percent, corresponding , respectively. Based on Table 601, respectively. Based on Table 601-2 of the CDOT 2011 Standar Specifications for Road and Bridge Construction, the onSpecifications for Road and Bridge Construction, the on-site soils represent a Class severity of sulfate exposure to concrete on a scale that ranges between Class 0 and Class severity of sulfate exposure to concrete on a scale that ranges between Class 0 and Class 3. Therefore, we recommend that the concrete used for this project should have a 3. Therefore, we recommend that the concrete used for this project should have a maximum water to cementitious material ratio of 0.45 and the cementitious materials should maximum water to cementitious material ratio of 0.45 and the cementitious materials should meet one of the below outlined requirements. meet one of the below outlined requirements. ASTM C 150 Type II or V; Class C fly ash shall not be substituted for cement.ASTM C 150 Type II or V; Class C fly ash shall not be substituted for cement. ASTM C 595 Type IP(MS) or IP(HS); ClaASTM C 595 Type IP(MS) or IP(HS); Cla ASTM C 1157 Type MS or HS; Class C fly ash shall not be substituted for cement.ASTM C 1157 Type MS or HS; Class C fly ash shall not be substituted for cement. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 24 9.7.2 Buried Metal Pipes The corrosion potential of the on-site materials was analyzed to evaluate its potential effects on buried metals. Corrosion potential was evaluated using the results of laboratory testing of samples obtained during the subsurface evaluation that were considered representative of soils at the subject site. The results of the laboratory testing indicate the on-site materials have low resistivity and could potentially be moderately corrosive to ferrous metals. Therefore, special consideration should be given to the use of heavy gauge, corrosion protected, underground steel pipe or culverts, if any are planned. As an alternative, plastic pipe or reinforced concrete pipe could be considered. A corrosion specialist should be consulted for further recommendations. 9.8 Scaling Climatic conditions in the project area including relatively low humidity, large temperature changes and repeated freeze-thaw cycles, may cause surficial scaling and spalling of exterior concrete. Occurrence of surficial scaling and spalling can be aggravated by poor workmanship during construction, such as “over-finishing” concrete surfaces and the use of de-icing salts on exterior concrete flatwork, particularly during the first winter after construction. The use of de- icing salts on nearby roadways, which can be transferred by vehicle traffic onto newly placed concrete, can be sufficient to induce scaling. The measures below can be beneficial for reducing the concrete scaling. However, because of the other factors involved, including workmanship, surface damage to concrete can develop even though the measures provided below were followed. The mix design criteria should be coordinated with other project requirements including the criteria for soluble sulfate resistance presented in Section 9.7.1. Curing concrete in accordance with applicable codes and guidelines. Maintaining a water/cement ratio of 0.45 by weight for exterior concrete mixes. Including Type F fly ash in exterior concrete mixes as 20 percent of the cementitious material. Specifying a 28-day, compressive strength of 4,500 or more psi for exterior concrete that may be exposed to de-icing salts. Avoiding the use of de-icing salts through the first winter after construction. If colored concrete is being proposed for use at this site, Ninyo & Moore should be consulted for additional recommendations. limatic conditions in the project area including relatively low humidity, large temperature limatic conditions in the project area including relatively low humidity, large temperature thaw cycles, may cause surficial scaling and spalling of exterior thaw cycles, may cause surficial scaling and spalling of exterior concrete. Occurrence of surficial scaling and spalling can be aggravated by poor workmanship concrete. Occurrence of surficial scaling and spalling can be aggravated by poor workmanship finishing””concrete surfaces and the use of deconcrete surfaces and the use of de exterior concrete flatwork, particularly during the first winter after construction. The use of deexterior concrete flatwork, particularly during the first winter after construction. The use of de icing salts on nearby roadways, whichicing salts on nearby roadways, which can be transferred by vehicle traffic onto newly placed can be transferred by vehicle traffic onto newly placed concrete, can be sufficient to induce scaling.concrete, can be sufficient to induce scaling. The measures below can be beneficial for reducing the concrete scaling. However, because of The measures below can be beneficial for reducing the concrete scaling. However, because of the other factors involved, including workmanship, surface damage to concrete can develop the other factors involved, including workmanship, surface damage to concrete can develop even though the measures provided below were followed. The mix design criteria should be even though the measures provided below were followed. The mix design criteria should be coordinated with other project requirements including the criteria for soluble sulfate rescoordinated with other project requirements including the criteria for soluble sulfate res Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 25 9.9 Frost Heave Site soils are susceptible to frost heave if allowed to become saturated and exposed to freezing temperatures and repeated freeze/thaw cycling. The formation of ice in the underlying soils can result in two or more inches of heave of pavements, flatwork and other hardscaping in sustained cold weather. A portion of this movement may be recovered when the soils thaw, but due to loss of soil density some degree of displacement will remain. Frost heave of hardscaping could also result in areas where the subgrade soils were placed on engineered fill. In areas where hardscape movements are a design concern (i.e. exterior flatwork located adjacent to the building within the doorway swing zone), replacement of the subgrade soils with 2 or more feet of clean, coarse sand or gravel, or supporting the element on foundations similar to the building, or spanning over a void should be considered. Recommendations in this regard can be provided upon request. 9.10 Construction in Cold or Wet Weather During construction, the site should be graded such that surface water can drain readily away from the building areas. Given the soil conditions, it is important to avoid ponding of water in or near excavations. Water that accumulates in excavations should be promptly pumped out or otherwise removed and these areas should be allowed to dry out before resuming construction. Berms, ditches, and similar means should be used to decrease stormwater entering the work area and to efficiently convey it off site. Earthwork activities undertaken during the cold weather season may be difficult and should be done by an experienced contractor. Fill should not be placed on top of frozen soils. The frozen soils should be removed prior to the placement of fill or other construction material. Frozen soil should not be used as engineered fill or backfill. The frozen soil may be reused (provided it meets the selection criteria) once it has thawed completely. In addition, compaction of the soils may be more difficult due to the viscosity change in water at lower temperatures. If construction proceeds during cold weather, foundations, slabs, or other concrete elements should not be placed on frozen subgrade soil. Frozen soil should either be removed from beneath concrete elements, or thawed and recompacted. To limit the potential for soil freezing, the time passing between excavation and construction should be minimized. Blankets, straw, soil cover, or heating may be used to discourage the soil from freezing. to the building, or spanning over a void should be considered. Recommendations in this regard to the building, or spanning over a void should be considered. Recommendations in this regard onstruction in Cold or Wet Weatheronstruction in Cold or Wet Weather During construction, the site should be graded such that surface water can drain readily away During construction, the site should be graded such that surface water can drain readily away from the building areas. Given the soil conditions, it is important to avoid ponding of water in or from the building areas. Given the soil conditions, it is important to avoid ponding of water in or near excavations. Water that accumulates in excavations should be promptly pumped out or near excavations. Water that accumulates in excavations should be promptly pumped out or otherwise removed and these areas should be allowed to dry out before resuming construction. otherwise removed and these areas should be allowed to dry out before resuming construction. Berms, ditches, and similar means should be used to decrease stormwater entering the work Berms, ditches, and similar means should be used to decrease stormwater entering the work efficiently convey it off site.efficiently convey it off site. Earthwork activities undertaken during the cold weather season may be difficult and should be Earthwork activities undertaken during the cold weather season may be difficult and should be done by an experienced contractor. Fill should not be placed on top of frozen soils. The frozen done by an experienced contractor. Fill should not be placed on top of frozen soils. The frozen soils should be removed prior to the placement of fill or other construction material. Frozen soil soils should be removed prior to the placement of fill or other construction material. Frozen soil should not be used as engineered fill or backfill. The frozen soil may be reused (provided it should not be used as engineered fill or backfill. The frozen soil may be reused (provided it Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 26 9.11 Site Drainage Infiltration of water into subsurface soils can lead to soil movement and associated distress, and chemically and physically related deterioration of concrete and masonry structures. To reduce the potential for infiltration of moisture into subsurface soils at the site, we recommend the following: Positive drainage should be established and maintained away from the proposed buildings. Positive drainage may be established by providing a surface gradient for paved areas of 2 to 5 percent or more for a distance of 10 feet or more away from structures. Where concrete flatwork is placed adjacent to structures and other considerations are required by law, such as ADA requirements, slopes of 1 percent or more are considered acceptable. For unpaved areas, positive drainage may be established by a slope of 5 to 10 percent for 10 feet or more away from structures, where possible. Adequate surface drainage should be provided to channel surface water away from on-site structures and off paved surfaces to a suitable outlet such as a storm drain. Adequate surface drainage may be enhanced by utilization of graded swales, area drains, and other drainage devices. Surface run-off should not be allowed to pond near structures. Building roof drains should have downspouts tightlined to an appropriate outlet, such as a storm drain or the street, away from structures, pavements, and flatwork. If tightlining of the downspouts is not practicable, they should discharge 5 feet or more away from structures and onto surfaces that slope away from the structure. Downspouts should not be allowed to discharge onto the ground surface adjacent to building foundations or on exterior walkways. The possibility of moisture infiltration beneath a structure, in the event of plumbing leaks, should be considered in the design and construction of underground water and sewer conduits. Permitting increases in moisture to the building supporting soils may result in a decrease in bearing capacity and an increase in settlement, heave, and/or differential movement. Incorporating a perimeter drainage system around the building foundations that will aid in reduction of the moisture infiltration of subsurface soils may be considered. Due to the proposed construction and anticipated utilities within the structures, not placing the perimeter drainage would be considered a low risk to the owner. Irrigated landscaping, consisting of sprinklers to water plants with high demands for water, should not be placed within 10 feet of the building(s). Drip irrigation is considered acceptable within this zone. Utility trenches should be backfilled with compacted, low permeability fill (i.e. permeability of 5-10 cm/s or less) within 5 feet of the building. Planters, if any, should be maintained 10 feet or more from the building and constructed with closed bottoms or with drainage systems to drain excess irrigation away from the building. 9.12 Construction Observation and Testing A qualified geotechnical consultant should perform appropriate observation and testing services during grading and construction operations. These services should include observation of any soft, loose, or otherwise unsuitable soils, evaluation of subgrade conditions where soil removals are performed, evaluation of the suitability of proposed borrow materials for use as fill, Adequate surface drainage should be provided to channel surface water away from onAdequate surface drainage should be provided to channel surface water away from on structures and off paved surfaces to a suitable outlet such as a storm drain. Adequate structures and off paved surfaces to a suitable outlet such as a storm drain. Adequate surface drainage may be enhanced by utilization of graded swales, area drains, and other surface drainage may be enhanced by utilization of graded swales, area drains, and other off should not be allowed to pond near structures.off should not be allowed to pond near structures. Building roof drains should have downspouts tightlined to an appropriate outlet, such as a Building roof drains should have downspouts tightlined to an appropriate outlet, such as a storm drain or the street, away from structures, pavements, and flatwork. If tightlining of the storm drain or the street, away from structures, pavements, and flatwork. If tightlining of the downspouts is not practicable, they should discharge 5downspouts is not practicable, they should discharge 5 feet or more away from structures d onto surfaces that slope away from the structure. Downspouts should not be allowed to d onto surfaces that slope away from the structure. Downspouts should not be allowed to discharge onto the ground surface adjacent to building foundations or on exterior walkways.discharge onto the ground surface adjacent to building foundations or on exterior walkways. The possibility of moisture infiltration beneath a structure, in the event of plumbing leaks, The possibility of moisture infiltration beneath a structure, in the event of plumbing leaks, should be considered in the design and construction of underground water and sewer should be considered in the design and construction of underground water and sewer conduits. Permitting increases in moisture to the building supporting soils may result in a conduits. Permitting increases in moisture to the building supporting soils may result in a decrease in bearing capacity and an increase in settlement, heave, and/or differential decrease in bearing capacity and an increase in settlement, heave, and/or differential movement. Incorporating a perimeter drainage system around the building foundations that movement. Incorporating a perimeter drainage system around the building foundations that will aid in reduction of the moisture infiltration of subsurface soils may be considered.will aid in reduction of the moisture infiltration of subsurface soils may be considered. the proposed construction and anticipated utilities within the structurethe proposed construction and anticipated utilities within the structure perimeter drainage would be considered a low risk to the owner.perimeter drainage would be considered a low risk to the owner. consisting of sprinklers consisting of sprinklers should not be placed within 10 feet of the building(s)should not be placed within 10 feet of the building(s) Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 27 evaluation of the stability of open temporary excavations, evaluation of the results of any subgrade stabilization or dewatering activities, and performance of observation and testing services during placement and compaction of engineered fill and backfill soils. The geotechnical consultant should also perform observation and testing services during placement of concrete, mortar, grout, asphalt concrete, and steel reinforcement. If another geotechnical consultant is selected to perform observation and testing services for the project, we request that the selected consultant provide a letter to the owner, with a copy to Ninyo & Moore, indicating that they fully understand our recommendations and that they are in full agreement with the recommendations contained in this report. Qualified subcontractors utilizing appropriate techniques and construction materials should perform construction of the proposed improvements. 9.13 Plan Review The recommendations presented in this report are based on preliminary design information for the proposed project and on the findings of our geotechnical evaluation. When finished, project plans and specifications should be reviewed by the geotechnical consultant prior to submitting the plans and specifications for bid. Additional field exploration and laboratory testing may be needed upon review of the project design plans. 9.14 Pre-Construction Meeting We recommend a pre-construction meeting be held. The owner or the owner’s representative, the architect, the contractor, and the geotechnical consultant should be in attendance to discuss the plans and the project. 10 LIMITATIONS The field evaluation, laboratory testing, and geotechnical analyses presented in this geotechnical report have been conducted in general accordance with current practice and the standard of care exercised by geotechnical consultants performing similar tasks in the project area. No warranty, expressed or implied, is made regarding the conclusions, recommendations, and opinions presented in this report. There is no evaluation detailed enough to reveal every subsurface condition. Variations may exist and conditions not observed or described in this report may be encountered during construction. Uncertainties relative to subsurface conditions can be reduced through additional subsurface exploration. Additional subsurface evaluation will be performed upon request. Please also note that our evaluation was limited to assessment of The recommendations presented in this report are based on preliminary design information for The recommendations presented in this report are based on preliminary design information for the proposed project and on the findings of our geotechnical evaluation. When finished, project the proposed project and on the findings of our geotechnical evaluation. When finished, project plans and specifications should be reviewed by the geotechnical consultant prior to submitting plans and specifications should be reviewed by the geotechnical consultant prior to submitting the plans and specifications for bid. Additional field exploration and laboratory testing may be the plans and specifications for bid. Additional field exploration and laboratory testing may be needed upon review of the project design plans.needed upon review of the project design plans. Construction MeetingConstruction Meeting onstruction meeting be held. The owner or the owneronstruction meeting be held. The owner or the owner the architect, the contractor, and the geotechnical consultant should be in attendance to discuss the architect, the contractor, and the geotechnical consultant should be in attendance to discuss the plans and the project.the plans and the project. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 28 the geotechnical aspects of the project, and did not include evaluation of structural issues, environmental concerns, or the presence of hazardous materials. This document is intended to be used only in its entirety. No portion of the document, by itself, is designed to completely represent any aspect of the project described herein. Ninyo & Moore should be contacted if the reader requires additional information or has questions regarding the content, interpretations presented, or completeness of this document. This report is intended for design purposes only. It does not provide sufficient data to prepare an accurate bid by contractors. It is suggested that the bidders and their geotechnical consultant perform an independent evaluation of the subsurface conditions in the project areas. The independent evaluations may include, but not be limited to, review of other geotechnical reports prepared for the adjacent areas, site reconnaissance, and additional exploration and laboratory testing. Our conclusions, recommendations, and opinions are based on an analysis of the observed site conditions. If geotechnical conditions different from those described in this report are encountered, our office should be notified and additional recommendations, if warranted, will be provided upon request. It should be understood that the conditions of a site could change with time as a result of natural processes or the activities of man at the subject site or nearby sites. In addition, changes to the applicable laws, regulations, codes, and standards of practice may occur due to government action or the broadening of knowledge. The findings of this report may, therefore, be invalidated over time, in part or in whole, by changes over which Ninyo & Moore has no control. This report is intended exclusively for use by the client. Any use or reuse of the findings, conclusions, and/or recommendations of this report by parties other than the client is undertaken at said parties’ sole risk. may include, but not be limited to, review of other geotechnical reports may include, but not be limited to, review of other geotechnical reports prepared for the adjacent areas, site reconnaissance, and additional exploration and prepared for the adjacent areas, site reconnaissance, and additional exploration and Our conclusions, recommendations, and opinions are based on an analysis of the observed site Our conclusions, recommendations, and opinions are based on an analysis of the observed site conditions. If geotechnical conditions different from those described in this report are conditions. If geotechnical conditions different from those described in this report are encountered, our office should be notified and additional recommendations, if warranted, will be encountered, our office should be notified and additional recommendations, if warranted, will be provided upon request. It should be understood that the conditions of a site could change with provided upon request. It should be understood that the conditions of a site could change with time as a result of natural processes or the activities of man at the subject site or nearby sites. time as a result of natural processes or the activities of man at the subject site or nearby sites. In addition, changes to the applicable laws, regulations, codes, and standards of practice may In addition, changes to the applicable laws, regulations, codes, and standards of practice may ment action or the broadening of knowledge. The findings of this report may, ment action or the broadening of knowledge. The findings of this report may, therefore, be invalidated over time, in part or in whole, by changes over which Ninyotherefore, be invalidated over time, in part or in whole, by changes over which Ninyo This report is intended exclusively for use by the client. Any use orThis report is intended exclusively for use by the client. Any use or conclusions, and/or recommendations of this report by parties other than the client is conclusions, and/or recommendations of this report by parties other than the client is Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 29 11 REFERENCES American Association of State Highway and Transportation Officials (AASHTO), 1993, AASHTO Guide for Design of Pavement Structures. American Association of State Highway and Transportation Officials (AASHTO), 2011, Standard Specifications for Transportation Materials and Methods of Sampling and Testing, 31st Edition, and Provisional Standards. American Concrete Institute (ACI), 2010, Guide to Design of Slabs-On-Ground (ACI 360R-10). American Concrete Institute (ACI), 2011, Building Code Requirements for Structural Concrete (ACI 318-11) and Commentary. American Concrete Institute (ACI), 2015, Guidelines for Concrete Floor and Slab Construction (ACI 302.1R-15). American Society for Testing and Materials (ASTM), 2015 Annual Book of ASTM Standards. Colorado Association of Geotechnical Engineers (CAGE), 2007, Geotechnical Study Guidelines for Light Commercial and Residential Buildings in Colorado, dated September. Colorado Association of Geotechnical Engineers (CAGE), 1996, Guideline for Slab Performance Risk Evaluation and Residential Basement Floor System Recommendations (Denver Metropolitan Area), dated December. Colorado Department of Transportation (CDOT), 2017, Standard Specifications for Road and Bridge Construction. Colton, Roger B., 1978, Geologic Map of the Boulder-Fort Collins-Greeley Area, Colorado, United States Geological Survey. Hart, Stephen S., 1973-1974, Potentially Swelling Soil and Rock in the Front Range Urban Corridor, Colorado: Colorado Geological Survey, Sheet 1 of 4. International Code Council, 2015, International Building Code. Kirkham, R.M., and Rogers, W.P., 1981, Earthquake potential in Colorado: Colorado Geological Survey Bulletin 43, 171 p., 3 pls. Ninyo & Moore, In-house proprietary information. Occupational Safety and Health Administration (OSHA), 2005, OSHA Standards for the Construction Industry, 29 CFR Part 1926: dated June. OSHPD, 2019, Seismic Design Maps, http://seismicmaps.org/. Rogers, W. P. and Widmann B. L., Fault Number 2324, Golden Fault; in Quaternary Fault and Fold Database of the United States: U.S. Geological Survey website, http://earthquakes.usgs.gov/regional/qfaults. Trimble, Donald E., 1980, The Geologic Story of the Great Plains, Geological Survey Bulletin 1493. United States Geological Survey and Colorado Geological Survey (USGS & CGS), 2019, Quaternary fault and fold database for the United States, accessed April 18, 2019, from USGS web site: http://earthquakes.usgs.gov/regional/qfaults/. Google Earth, October 1999, October 2017. Colorado Association of Geotechnical Engineers (CAGE), 2007, Geotechnical Study Guidelines Colorado Association of Geotechnical Engineers (CAGE), 2007, Geotechnical Study Guidelines cial and Residential Buildings in Colorado, dated September.cial and Residential Buildings in Colorado, dated September. Colorado Association of Geotechnical Engineers (CAGE), 1996, Guideline for Slab Performance Colorado Association of Geotechnical Engineers (CAGE), 1996, Guideline for Slab Performance Risk Evaluation and Residential Basement Floor System Recommendations (Denver Risk Evaluation and Residential Basement Floor System Recommendations (Denver Colorado Department of Transportation (CDOT), 201Colorado Department of Transportation (CDOT), 2017, Standard Specifications for Road and , Standard Specifications for Road and Colton, Roger B., 1978, Geologic Map of the BoulderColton, Roger B., 1978, Geologic Map of the Boulder--Fort CollinsFort Collins United States Geological Survey. 1974, Potentially Swelling Soil and Rock in the Front Range Urban 1974, Potentially Swelling Soil and Rock in the Front Range Urban Corridor, Colorado: Colorado Geological Survey, Sheet 1 of 4.Corridor, Colorado: Colorado Geological Survey, Sheet 1 of 4. International Code Council, 2015, International Building Code.International Code Council, 2015, International Building Code. Kirkham, R.M., and Rogers, W.P., 1981, Earthquake potential in Colorado: Colorado Geological Kirkham, R.M., and Rogers, W.P., 1981, Earthquake potential in Colorado: Colorado Geological Survey Bulletin 43, 171 p., 3 pls.Survey Bulletin 43, 171 p., 3 pls. house proprietary information.house proprietary information. Occupational Safety and Health Administration (OSHA), 2005, OSHA Standards for the Occupational Safety and Health Administration (OSHA), 2005, OSHA Standards for the Construction Industry, 29 CFR Part 1926: dated JuneConstruction Industry, 29 CFR Part 1926: dated June OSHPD, 2019, Seismic Design Maps, http://seismicmaps.org/.OSHPD, 2019, Seismic Design Maps, http://seismicmaps.org/. Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 Appendix A Photographic Documentation FIGURESFIGURES 501710001 | 6/19 REDMAN DRIVE AND NORTHWEST FRONTAGE ROAD FORT COLLINS, COLORADO POUDRE VALLEY DEVELOPMENT NOTE: DIMENSIONS, DIRECTIONS AND LOCATIONS ARE APPROXIMATE. Source: US Geological Survey 7.5-minute topographic map, Fort Collins and Timnath, Colorado, 2016. 0 2000 FEET N bsm file no: 1710blm0619 Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 APPENDIX A Boring Logs APPENDIX A Boring Logs Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 APPENDIX A BORING LOGS Field Procedure for the Collection of Disturbed Samples Disturbed soil samples were obtained in the field using the following methods. Bulk Samples Bulk samples of representative earth materials were obtained from the exploratory borings. The samples were bagged and transported to the laboratory for testing. Field Procedure for the Collection of Ring-lined Samples Ring-lined soil samples were obtained in the field using the following methods. The Modified California Split-Barrel Drive Sampler The sampler, with an external diameter of 3.0 inches, was lined with thin brass rings with inside diameters of approximately 2.4 inches. The sample barrel was driven into the ground with the weight of a hammer in general accordance with ASTM D 3550. The driving weight was permitted to fall freely. The approximate length of the fall, the weight of the hammer or bar, and the number of blows per foot of driving are presented on the boring logs as an index to the relative resistance of the materials sampled. The samples were removed from the sample barrel in the brass rings, sealed, and transported to the laboratory for testing. The California Drive Sampler The sampler, with an external diameter of 2.4 inches, was lined with four 4-inch long, thin brass rings with inside diameters of approximately 1.9 inches. The sample barrel was driven into the ground with the weight of a hammer in general accordance with ASTM D 3550. The driving weight was permitted to fall freely. The approximate length of the fall, the weight of the hammer, and the number of blows per foot of driving are presented on the boring logs as an index to the relative resistance of the materials sampled. The samples were removed from the sample barrel in the brass liners, sealed, and transported to the laboratory for testing. The sampler, with an external diameter of 3.0 inches, was lined with thin brass rings with The sampler, with an external diameter of 3.0 inches, was lined with thin brass rings with approximately 2.4 inches. The sample barrel was driven into the ground approximately 2.4 inches. The sample barrel was driven into the ground with the weight of a hammer in general accordance with ASTM Dwith the weight of a hammer in general accordance with ASTM D 3550. The driving weight was permitted to fall freely. The approximate length of the fall, the weight of the hammer or was permitted to fall freely. The approximate length of the fall, the weight of the hammer or , and the number of blows per foot of driving are presented on the boring logs as an , and the number of blows per foot of driving are presented on the boring logs as an index to the relative resistance of the materials sampled. The samples were removed from index to the relative resistance of the materials sampled. The samples were removed from the sample barrel in the brass rings, sealed, and transported to the laboratory fothe sample barrel in the brass rings, sealed, and transported to the laboratory fo The sampler, with an external diameter of 2.4 inches, was lined with four 4The sampler, with an external diameter of 2.4 inches, was lined with four 4 brass rings with inside diameters of approximately 1.9 inches. The sample barrel was brass rings with inside diameters of approximately 1.9 inches. The sample barrel was driven into the ground with the weight of a hammer in general accordance with ASTM driven into the ground with the weight of a hammer in general accordance with ASTM 3550. The driving weight was permitted to fall freely. The approximate length of the fall, 3550. The driving weight was permitted to fall freely. The approximate length of the fall, the weight of the hammer, and the number of blows per foot of driving are presented on the the weight of the hammer, and the number of blows per foot of driving are presented on the boring logs as an index to the relative resistance of the materials sampled. The samples boring logs as an index to the relative resistance of the materials sampled. The samples were removed from the sample barrel in the brass liners, sealed, and transported to the were removed from the sample barrel in the brass liners, sealed, and transported to the laboratory for testing.laboratory for testing. PRIMARY DIVISIONS SECONDARY DIVISIONS GROUP SYMBOL GROUP NAME COARSE- GRAINED SOILS more than 50% retained on No. 200 sieve GRAVEL more than 50% of coarse fraction retained on No. 4 sieve CLEAN GRAVEL GW well-graded GRAVEL GP poorly graded GRAVEL GRAVEL with DUAL CLASSIFICATIONS GW-GM well-graded GRAVEL with silt GP-GM poorly graded GRAVEL with silt GW-GC well-graded GRAVEL with clay GP-GC poorly graded GRAVEL with clay GRAVEL with FINES more than GM silty GRAVEL GC clayey GRAVEL GC-GM silty, clayey GRAVEL SAND 50% or more of coarse fraction passes No. 4 sieve CLEAN SAND SW well-graded SAND SP poorly graded SAND SAND with DUAL CLASSIFICATIONS SW-SM well-graded SAND with silt SP-SM poorly graded SAND with silt SW-SC well-graded SAND with clay SP-SC poorly graded SAND with clay SAND with FINES more than SM silty SAND SC clayey SAND SC-SM silty, clayey SAND FINE- GRAINED SOILS 50% or more passes No. 200 sieve SILT and CLAY liquid limit less than 50% INORGANIC CL lean CLAY ML SILT CL-ML silty CLAY ORGANIC OL (PI > 4) organic CLAY OL (PI < 4) organic SILT SILT and CLAY liquid limit 50% or more INORGANIC CH fat CLAY MH elastic SILT ORGANIC OH (plots on or above “A”-line)organic CLAY OH (plots below “A”-line)organic SILT Highly Organic Soils PT Peat USCS METHOD OF SOIL CLASSIFICATION Explanation of USCS Method of Soil Classification PROJECT NO. DATE FIGURE APPARENT DENSITY SPOOLING CABLE OR CATHEAD AUTOMATIC TRIP HAMMER SPT (blows/foot) MODIFIEDSPLIT BARREL (blows/foot) SPT (blows/foot) MODIFIEDSPLIT BARREL (blows/foot) Very Loose < 4 < 8 < 3 < 5 Loose 5 - 10 9 - 21 4 - 7 6 - 14 Medium Dense 11 - 30 22 - 63 8 - 20 15 - 42 Dense 31 - 50 64 - 105 21 - 33 43 - 70 Very Dense > 50 > 105 > 33 > 70 CONSIS- TENCY SPOOLING CABLE OR CATHEAD AUTOMATIC TRIP HAMMER SPT (blows/foot) MODIFIEDSPLIT BARREL (blows/foot) SPT (blows/foot) MODIFIEDSPLIT BARREL (blows/foot) Very Soft < 2 < 3 < 1 < 2 Soft 2 - 4 3 - 5 1 - 3 2 - 3 Firm 5 - 8 6 - 10 4 - 5 4 - 6 Stiff 9 - 15 11 - 20 6 - 10 7 - 13 Very Stiff 16 - 30 21 - 39 11 - 20 14 - 26 Hard > 30 > 39 > 20 > 26 LIQUID LIMIT (LL), % 0 10 107 4 20 30 40 50 60 70 0 20 30 40 50 60 70 80 90 100 MH or OH ML or OLCL - ML DESCRIPTION SIEVE SIZE GRAIN SIZE APPROXIMATE SIZE Boulders > 12” > 12” Larger than basketball-sized Cobbles 3 - 12” 3 - 12” Fist-sized to basketball-sized Gravel Coarse 3/4 - 3” 3/4 - 3” Thumb-sized to Fine #4 - 3/4” 0.19 - 0.75” Pea-sized to thumb-sized Sand Coarse #10 - #4 0.079 - 0.19” Rock-salt-sized to pea-sized Medium #40 - #10 0.017 - 0.079” Sugar-sized to rock-salt-sized Fine #200 - #40 0.0029 - 0.017” Flour-sized to sugar-sized Fines Passing #200 < 0.0029” Flour-sized and smaller CH or OH CL or OL well-graded SAND with clay poorly graded SAND with clay silty SANDsilty SAND clayey SANDclayey SAND silty, clayey SAND lean CLAY SILTSILT CL-ML silty CLAYsilty CLAY OL (PI > 4)organic CLAY OL (PI < 4) CH OH (plots on or above “A”-line) OH (plots below “A”-line) Fines BORING LOG EXPLANATION SHEET 0 5 XX/XX 10 15 Bulk sample. Modified split-barrel drive sampler. 2-inch inner diameter split-barrel drive sampler. No recovery with modified split-barrel drive sampler, or 2-inch inner diameter split-barrel drive sampler. Sample retained by others. Standard Penetration Test (SPT). No recovery with a SPT. Shelby tube sample. Distance pushed in inches/length of sample recovered in inches. No recovery with Shelby tube sampler. Continuous Push Sample. Seepage. Groundwater encountered during drilling. Groundwater measured after drilling. SM MAJOR MATERIAL TYPE (SOIL): Solid line denotes unit change. CL Dashed line denotes material change. Attitudes: Strike/Dip b: Bedding c: Contact j: Joint f: Fracture F: Fault cs: Clay Seam s: Shear bss: Basal Slide Surface sf: Shear Fracture sz: Shear Zone sbs: Shear Bedding Surface The total depth line is a solid line that is drawn at the bottom of the boring. 20 BORING LOG Explanation of Boring Log Symbols PROJECT NO. DATE FIGURE Shelby tube sample. Distance pushed in inchShelby tube sample. Distance pushed in inches/length of sample recovered in inches. es/length of sample recovered in inches. No recovery with Shelby tube sampler. No recovery with Shelby tube sampler. Continuous Push Sample. Continuous Push Sample. Seepage. Seepage. GroGroundwater encountered duundwater encountered du Groundwater measured after drilling. Groundwater measured after drilling. SM MAJOR MATERIAL TYPE (SOIL)MAJOR MATERIAL TYPE (SOIL) Solid line denotes unit change. Solid line denotes unit change. CL Dashed line denotes material change. Dashed line denotes material change. Attitudes: Strike/Dip Attitudes: Strike/Dip b: Bedding b: Bedding c: Contact c: Contact 0 10 20 30 40 17 5 43 7 34 20.9 15.0 6.7 106.6 106.2 122.2 CH CL-ML SW SM SP LOAM: Brown, moist, very stiff, fat CLAY; trace sand and gravel. ALLUVIUM: Red, moist, firm, sandy silty CLAY. Red with yellow and gray, wet, dense, fine to coarse SAND with gravel; trace clay. @10': Groundwater encountered during drilling. Light brown with red, wet, loose, silty SAND; trace iron oxide staining. Light brown with red, wet, very dense, fine to medium SAND; trace clay. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 1 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-1 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Red with yellow and gray, wet, dense, fine to coarse SAND with gravel; trace clay.Red with yellow and gray, wet, dense, fine to coarse SAND with gravel; trace clay. @10': Groundwater encountered during drilling.@10': Groundwater encountered during drilling. Light brown with red, wet, loose, silty SAND; trace iron oxide staining.Light brown with red, wet, loose, silty SAND; trace iron oxide staining. Light brown with red, wet, very dense, fine to medium SAND; trace clay.Light brown with red, wet, very dense, fine to medium SAND; trace clay. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling.Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 18 5 15 90/10" 21.4 17.3 103.9 104.3 CH CL SW LOAM: Brown with white, moist, very stiff, sandy fat CLAY with few calcium mineralizations. ALLUVIUM: Red, moist, firm, sandy lean CLAY; trace gravel. Light brown with red, moist, medium dense, fine to coarse SAND; trace clay. @12': Groundwater encountered during drilling. Wet; very dense. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 12 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 2 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-2 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Light brown with red, moist, medium dense, fine to coarse SAND; trace clay.Light brown with red, moist, medium dense, fine to coarse SAND; trace clay. @12': Groundwater encountered during drilling.@12': Groundwater encountered during drilling. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 12 feet during drilling.Groundwater was encountered at a depth of approximately 12 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 12 5 25 7 16.8 17.1 3.8 111.8 106.8 CH CL SW LOAM: Brown, moist, sandy fat CLAY. ALLUVIUM: Pale red to red, moist, stiff, lean CLAY with sand. Firm. Pale red to light brown, moist to wet, moderately dense, fine to coarse SAND with gravel; trace clay. @11': Groundwater encountered during drilling. Loose with few clayey interlayers. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 11 feet during drilling. Backfilled with on-site soils on 06/08/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 3 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-3 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Pale red to light brown, moist to wet, moderately dense, fine to coarse SAND with gravel;Pale red to light brown, moist to wet, moderately dense, fine to coarse SAND with gravel; @11': Groundwater encountered during drilling.@11': Groundwater encountered during drilling. Loose with few clayey interlayers.Loose with few clayey interlayers. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 11 feet during drilling.Groundwater was encountered at a depth of approximately 11 feet during drilling. Backfilled with on-site soils on 06/08/2019.Backfilled with on-site soils on 06/08/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 10 3 36 17 14.4 16.0 6.1 113.2 109.5 123.7 CL SC SW LOAM: Light brown to brown, moist, stiff, sandy lean CLAY; trace gravel. ALLUVIUM: Reddish brown, moist, very loose, clayey SAND. Reddish brown, moist to wet, medium dense, fine to coarse SAND with gravel; trace clay. @10': Groundwater encountered during drilling. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/08/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 4 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-4 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @10': Groundwater encountered during drilling.@10': Groundwater encountered during drilling. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling.Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/08/2019.Backfilled with on-site soils on 06/08/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 19 6 24 20 20.8 15.3 106.7 107.8 CH CL SW LOAM: Reddish brown to brown mottled, moist, very stiff, fat CLAY; trace sand. Red, moist, firm, sandy lean CLAY. ALLUVIUM: Light brown to red, moist, medium dense, fine to coarse SAND; trace clay. @11': Groundwater encountered during drilling. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 11 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 5 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-5 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Light brown to red, moist, medium dense, fine to coarse SAND; trace clay.Light brown to red, moist, medium dense, fine to coarse SAND; trace clay. @11': Groundwater encountered during drilling.@11': Groundwater encountered during drilling. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 11 feet during drilling.Groundwater was encountered at a depth of approximately 11 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 13 7 24 9 19.1 27.0 2.4 106.1 93.9 CH CH SW LOAM: Reddish brown, moist, stiff, fat CLAY; trace sand and gravel. ALLUVIUM: Pale red to red, moist, stiff, fat CLAY; trace sand. Reddish brown with white and gray, moist, medium dense, fine to coarse SAND with gravel; trace clay. @11': Groundwater encountered during drilling. Total Depth = 15.5 feet. Groundwater was encountered at a depth of approximately 11 feet during drilling. Backfilled with on-site soils on 06/08/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 6 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-6 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @11': Groundwater encountered during drilling.@11': Groundwater encountered during drilling. Total Depth = 15.5 feet.Total Depth = 15.5 feet. Groundwater was encountered at a depth of approximately 11 feet during drilling.Groundwater was encountered at a depth of approximately 11 feet during drilling. Backfilled with on-site soils on 06/08/2019.Backfilled with on-site soils on 06/08/2019. Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 14 6 37 37 20 16.0 15.8 5.7 110.7 107.6 128.1 CL CL SW LOAM: Red to brown, moist, very stiff, lean CLAY; trace sand. Red to reddish brown, moist, firm, sandy lean CLAY. ALLUVIUM: Pale red to red, moist to wet, medium dense, fine to coarse SAND with gravel; trace clay. @10': Groundwater encountered during drilling. Pale brown to yellowish brown. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 7 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-7 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Pale red to red, moist to wet, medium dense, fine to coarse SAND with gravel; trace clay.Pale red to red, moist to wet, medium dense, fine to coarse SAND with gravel; trace clay. @10': Groundwater encountered during drilling.@10': Groundwater encountered during drilling. Pale brown to yellowish brown.Pale brown to yellowish brown. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling.Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 19 20 27 32 51 26.9 7.7 98.6 126.0 CL CH SW LOAM: Brown to reddish brown, moist, very stiff, fat CLAY; trace sand, gravel, and few calcium mineralizations. ALLUVIUM: Red to reddish brown, moist, very stiff, fat CLAY; trace sand and gravel. Red to reddish brown, moist, medium dense, fine to coarse SAND with gravel; trace clay. @12': Groundwater encountered during drilling. Wet; dense. Very dense; grading to clayey sand. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 12 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 8 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-8 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Red to reddish brown, moist, medium dense, fine to coarse SAND with gravel; trace clay.Red to reddish brown, moist, medium dense, fine to coarse SAND with gravel; trace clay. @12': Groundwater encountered during drilling.@12': Groundwater encountered during drilling. Very dense; grading to clayey sand.Very dense; grading to clayey sand. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 12 feet during drilling.Groundwater was encountered at a depth of approximately 12 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 17 16 50/5" 20 21.9 1.8 102.0 123.1 CH SW-SC LOAM: Brown with white, moist, very stiff, sandy fat CLAY with few calcium mineralizations. ALLUVIUM: Reddish brown to yellowish brown, moist, medium dense, fine to coarse SAND with clay and gravel. @9': Groundwater encountered during drilling. Very dense. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 9 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-9 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @9': Groundwater encountered during drilling.@9': Groundwater encountered during drilling. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling.Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 14 6 22 15 30 21.2 8.2 103.7 120.5 CH SC-SM SW LOAM: Brown and reddish brown mottled, moist, very stiff, sandy fat CLAY. ALLUVIUM: Red to reddish brown, moist, loose, silty, clayey SAND with gravel. @9': Groundwater encountered during drilling. Light brown to reddish brown, wet, medium dense, fine to coarse SAND; trace clay. Dense. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 10 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-10 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @9': Groundwater encountered during drilling.@9': Groundwater encountered during drilling. Light brown to reddish brown, wet, medium dense, fine to coarse SAND; trace clay.Light brown to reddish brown, wet, medium dense, fine to coarse SAND; trace clay. Dense.Dense. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling.Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 6 12 50/3" 23 11.4 2.0 107.8 CL SP LOAM: Pale red to red, moist, firm, lean CLAY; trace sand. ALLUVIUM: Reddish yellow to pale red, moist, loose, fine to medium SAND. @9': Groundwater encountered during drilling. Very dense. @10': Scattered cobbles. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/08/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 11 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-11 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @9': Groundwater encountered during drilling.@9': Groundwater encountered during drilling. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling.Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/08/2019.Backfilled with on-site soils on 06/08/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 15 13 8 9 1.1 CH SW LOAM: Brown, moist, very stiff, sandy fat CLAY with gravel. ALLUVIUM: Red to reddish brown, moist, loose, fine to coarse SAND with gravel; trace clay. @8.5': Groundwater encountered during drilling. Wet; medium dense; with few clayey fine sand interlayers. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 8.5 feet during drilling. Backfilled with on-site soils on 06/08/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 12 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-12 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @8.5': Groundwater encountered during drilling.@8.5': Groundwater encountered during drilling. Wet; medium dense; with few clayey fine sand interlayers.Wet; medium dense; with few clayey fine sand interlayers. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 8.5 feet during drilling.Groundwater was encountered at a depth of approximately 8.5 feet during drilling. Backfilled with on-site soils on 06/08/2019.Backfilled with on-site soils on 06/08/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 4 6 50 30 15.5 4.1 106.5 106.0 CH CL SC SW LOAM: Brown, moist, sandy fat CLAY. ALLUVIUM: Red, moist, firm, sandy lean CLAY; trace gravel. Red with gray and brown, moist, loose, clayey SAND with gravel. Red with gray and brown, moist, very dense, fine to coarse SAND; trace clay. @9': Groundwater encountered during drilling. Dense. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/07/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 13 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/07/2019 BORING NO.B-13 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Red with gray and brown, moist, very dense, fine to coarse SAND; trace clay.Red with gray and brown, moist, very dense, fine to coarse SAND; trace clay. @9': Groundwater encountered during drilling.@9': Groundwater encountered during drilling. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling.Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/07/2019.Backfilled with on-site soils on 06/07/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. 0 10 20 30 40 13 17 64 37 14 10.4 8.0 119.9 142.4 CH SW-SC LOAM: Brown to dark brown, moist, stiff, sandy fat CLAY. ALLUVIUM: Reddish yellow to yellow, dry, medium dense, fine to coarse SAND with clay and gravel. @9': Groundwater encountered during drilling. Wet; dense. Medium dense. Light brown. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 14 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-14 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @9': Groundwater encountered during drilling.@9': Groundwater encountered during drilling. Light brown.Light brown. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling.Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 18 10 50 27 19 17.2 6.8 109.5 102.6 CH SM SP-SC LOAM: Brown to dark brown, moist, very stiff, fat CLAY with sand; trace gravel and calcium mineralizations. ALLUVIUM: Pale red to reddish yellow, dry, loose, silty SAND; trace gravel. Pale red to reddish yellow, wet, very dense, fine to medium SAND with clay and gravel. @10': Groundwater encountered during drilling. Dense. Medium dense. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/03/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 15 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/03/2019 BORING NO.B-15 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 Pale red to reddish yellow, wet, very dense, fine to medium SAND with clay and gravel.Pale red to reddish yellow, wet, very dense, fine to medium SAND with clay and gravel. @10': Groundwater encountered during drilling.@10': Groundwater encountered during drilling. Medium dense.Medium dense. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 10 feet during drilling.Groundwater was encountered at a depth of approximately 10 feet during drilling. Backfilled with on-site soils on 06/03/2019.Backfilled with on-site soils on 06/03/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 13 5 50/2" 11 14 12.4 110.9 CL SC LOAM: Brown with white and red, moist, stiff, sandy lean CLAY; trace gravel. ALLUVIUM: Pale red to pale reddish brown, moist to wet, loose, clayey SAND; trace gravel and scattered cobbles. @8.5': Groundwater encountered during drilling. Very dense. Medium dense; few clayey interlayers. Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 8.5 feet during drilling. Backfilled with on-site soils on 06/08/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 16 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-16 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @8.5': Groundwater encountered during drilling.@8.5': Groundwater encountered during drilling. Medium dense; few clayey interlayers.Medium dense; few clayey interlayers. Total Depth = 20.5 feet.Total Depth = 20.5 feet. Groundwater was encountered at a depth of approximately 8.5 feet during drilling.Groundwater was encountered at a depth of approximately 8.5 feet during drilling. Backfilled with on-site soils on 06/08/2019.Backfilled with on-site soils on 06/08/2019. NotesNotes: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is 0 10 20 30 40 18 14 29 19 16.7 5.8 8.1 109.9 124.6 132.7 CL SC SW LOAM: Brown with white and red, moist, very stiff, lean CLAY with sand; trace gravel. ALLUVIUM: Reddish brown to brown, moist, loose, clayey SAND with gravel. @8': Groundwater encountered during drilling. Wet; medium dense. Reddish brown, wet, medium dense, fine to coarse SAND; trace clay and gravel. Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/07/2019. Notes: Groundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents. FIGURE A- 17 POUDRE VALLEY DEVELOPMENT FORT COLLINS, COLORADO 501710001 |7/19 DESCRIPTION/INTERPRETATION DATE DRILLED 06/08/2019 BORING NO.B-17 GROUND ELEVATION --SHEET 1 OF METHOD OF DRILLING CME-45, 4" Solid-Stem Auger (Unlimited Access Drilling) DRIVE WEIGHT 140 Lbs. (Automatic-Trip Hammer)DROP 30" SAMPLED BY DLH LOGGED BY DLH REVIEWED BY BFG 1 @8': Groundwater encountered during drilling.@8': Groundwater encountered during drilling. Reddish brown, wet, medium dense, fine to coarse SAND; trace clay and gravel.Reddish brown, wet, medium dense, fine to coarse SAND; trace clay and gravel. Total Depth = 19 feet.Total Depth = 19 feet. Groundwater was encountered at a depth of approximately 9 feet during drilling.Groundwater was encountered at a depth of approximately 9 feet during drilling. Backfilled with on-site soils on 06/07/2019.Backfilled with on-site soils on 06/07/2019. NotesNotes:: Groundwater may rise to a level higher than that measured in borehole due to seasonalGroundwater may rise to a level higher than that measured in borehole due to seasonal variations in precipitation and several other factors as discussed in the report.variations in precipitation and several other factors as discussed in the report. The ground elevation shown above is an estimation only. It is based on our interpretationsThe ground elevation shown above is an estimation only. It is based on our interpretations of published maps and other documents reviewed for the purposes of this evaluation. It isof published maps and other documents reviewed for the purposes of this evaluation. It is not sufficiently accurate for preparing construction bids and design documents.not sufficiently accurate for preparing construction bids and design documents. ~4851.5 Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 APPENDIX B Laboratory Testing Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 APPENDIX B LABORATORY TESTING Classification Soils were visually and texturally classified in accordance with the Unified Soil Classifications System (USCS) in general accordance with ASTM D 2488. Soil classifications are indicated on the logs of the exploratory excavations in Appendix A. In-Place Moisture and Density Tests The moisture content and dry density of ring-lined samples obtained from the exploratory borings were evaluated in general accordance with ASTM D 2837. These test results are presented on the logs of the exploratory borings in Appendix A. Atterberg Limits Tests were performed on selected representative fine-grained soil samples to evaluate the liquid limit, plastic limit, and plasticity index in general accordance with ASTM D 4318. These test results were utilized to evaluate the soil classification in accordance with the Unified Soil Classification System. The test results and classifications are shown on Figures B-1 through B-4. No. 200 Sieve Analysis An evaluation of the percentage of particles finer than the No. 200 sieve in selected soil samples was performed in general accordance with ASTM D 1140. The results of the tests are presented on Figures B-5 through B-7. Consolidation/Swell Tests Consolidation/swell tests were performed on selected ring-lined soil samples in general accordance with ASTM D 4546. The samples were inundated during testing to represent adverse field conditions. The percent of consolidation or swell for each load cycle was recorded as a ratio of the amount of vertical compression to the original height of the sample. The results of the tests are summarized on Figures B-8 through B-25. Soil Corrosivity Tests A soil pH test was performed on a representative sample in general accordance with ASTM Test Method D 4972. A soil minimum resistivity test was performed on a representative sample in general accordance with AASHTO T288. The sulfate content of a selected sample was evaluated in general accordance with CDOT Test Method CP-L 2103. The chloride content of a selected sample was evaluated in general accordance with CDOT Test Method CP-L 2104. The test results are presented on Figure B-26. results were utilized to evaluate the soil classification in accordanceresults were utilized to evaluate the soil classification in accordance Classification System. The test results and classifications are shown on FiguresClassification System. The test results and classifications are shown on Figures An evaluation of the percentage of particles finer than the No. 200 sieve in selected soil An evaluation of the percentage of particles finer than the No. 200 sieve in selected soil samples was performed in general accordance with ASTM Dsamples was performed in general accordance with ASTM D 1140. The results of the tests are 1140. The results of the tests are Consolidation/swell tests were performed on selected ringConsolidation/swell tests were performed on selected ring 4546. The samples were inundated during testing to represent samples were inundated during testing to represent adverse field conditions. The percent of consolidation or swell for each load cycle was recorded adverse field conditions. The percent of consolidation or swell for each load cycle was recorded as a ratio of the amount of vertical compression to the original height of the sample. The results as a ratio of the amount of vertical compression to the original height of the sample. The results sts are summarized on Figures Bsts are summarized on Figures B-8 -8 through Bthrough B A soil pH test was performed on a representative sample in general accordance with ASTM Test A soil pH test was performed on a representative sample in general accordance with ASTM Test Method D 4972. A soil minimum resistivity test was performed on a representative sample in Method D 4972. A soil minimum resistivity test was performed on a representative sample in eneral accordance with AASHTO T288. The sulfate content of a selected sample was eneral accordance with AASHTO T288. The sulfate content of a selected sample was evaluated in general accordance with CDOT Test Method CPevaluated in general accordance with CDOT Test Method CP selected sample was evaluated in general accordance with CDOT Test Method CPselected sample was evaluated in general accordance with CDOT Test Method CP test results are presented on Figure Btest results are presented on Figure B X X Ninyo & Moore |Proposed Poudre Valley Development, Fort Collins, Colorado |501710001 R |July 2, 2019 6001 South Willow Drive, Suite 195 |Greenwood Village, Colorado 80111 |p. 303.629.6000 ARIZONA | CALIFORNIA | COLORADO | NEVADA | TEXAS | UTAH www.ninyoandmoore.com 309 South Summit View Drive, Unit 6 | Fort Collins, Colorado 805241 | p. 303.629.6000 | www.ninyoandmoore.com October 3, 2019 Project No. 501710003 Mr. Josh Heiney Comunale Properties 1855 South Pearl Street, Suite 20 Denver, Colorado 80210 Subject: Supplemental Geotechnical Evaluation Percolation Testing Mulberry Connection Redman Drive & NW Frontage Road Fort Collins, Colorado Reference: Ninyo & Moore, 2019, Geotechnical Evaluation, Proposed Poudre Valley Development, Redman Drive & NW Frontage Road, Fort Collins, Colorado, dated July 2. Dear Mr. Heiney: In accordance with your authorization, we have performed a supplemental geotechnical evaluation for the proposed Mulberry Connection industrial project located at the northwest corner of Redman Drive and Northwest Frontage Road in Fort Collins, Colorado (Figure 1). The purpose of our supplemental geotechnical evaluation was to assess the percolation rate within the proposed stormwater detention ponds (Figure 2). This report presents the results of the percolation testing. Our referenced report dated July 2, 2019 presented our methodology, findings, conclusions, and limitations regarding the geotechnical conditions and our geotechnical recommendations for the proposed development. Recommendations and limitations provided in the referenced report remain valid, except where superseded herein. PROPOSED CONSTRUCTION As a part of the proposed development, detention basins will be constructed to the south, west, and east of the proposed structures. We understand the basins will require excavations ranging from less than 1 foot to up to approximately 3 feet below existing site grades. PERCOLATION TESTING Percolation testing was performed by hand-excavating 12, approximately 8- to 10-inch diameter, percolation holes that ranged from approximately 30 to 37 inches below the existing site grades. Borings performed as a part of our subsurface exploration in the vicinity of the detention basins Ninyo & Moore | Mulberry Connection Percolation Tests, Fort Collins, Colorado | 501710003 | October 3, 2019 were utilized for determination of soil profiles in the area. Along the eastern and southeastern portion of the site, subsurface conditions generally consisted of approximately 2 to 4 feet of clay loam underlain by clay alluvial soils to depths of approximately 9 to 9.5 feet below ground surface (bgs). Sandy alluvial deposits were encountered below the clay alluvial deposits. Along the western and southwestern portion of the site, approximately 4 feet of clay loam was encountered underlain by sandy alluvial deposits. Groundwater was observed in our borings at depths of approximately 8.5 to 12 feet bgs. Our percolation testing procedures consisted of excavating the percolation holes with an electric auger. Once excavated, the sides of the holes were roughening, as needed, and the percolation holes were pre-soaked. Approximately 2 inches of sand was added to the bottom of the holes prior to the holes being pre-soaked for approximately 24 hours. In accordance with Larimer County Health and Environment percolation testing requirements, each percolation test was conducted over a 4-hour period with measurements obtained at 30-minute intervals. The water level drop in the final 30-minute interval was used to calculate the percolation rate. The results of the percolation testing are presented in Appendix A. In order to account for the site variability, the limited number of tests performed, and to account for siltation, a correction factor of 2 should be applied to the calculated average percolation rate per basin. This report is intended exclusively for use by the client. Any use or reuse of the findings, conclusions, and/or recommendations of this report by parties other than the client is undertaken at said parties’ sole risk. We appreciate the opportunity to be of continued service to you during this phase of the project. Respectfully submitted, NINYO & MOORE Kelley Lange, EI Senior Staff Engineer Brian F. Gisi, PE Principal Engineer KL/BFG Attachments: Figure 1 – Site Location Figure 2 – Percolation Test Locations Appendix A – Percolation Test Results Distribution: (1) Addressee (via email) (1) Mr. Dan Skeehan, PE, Kimley Horn (via email) 10/3/2019 Ninyo & Moore | Mulberry Connection Percolation Tests, Fort Collins, Colorado | 501710003 | October 3, 2019 Appendix A Photographic Documentation FIGURES Ninyo & Moore | Mulberry Connection Percolation Tests, Fort Collins, Colorado | 501710003 | October 3, 2019 APPENDIX A Percolation Tests Project Number: 501710003 Test Date: 9/13/2019 Project: Mulberry Connection Tested By: FT Location: Fort Collins Elevation: - +/- (MSL) Hole Number Hole Depth Time Interval Initial Water Level Height at Start Final Water Level Height at End Drop in Water Level Average Percolation Rate Time Start Time Stop (inches) (minutes) (inches) (inches) (inches) (min/in) (hh:mm) (hh:mm) P1-1 37 0 29.00 29.00 0.00 Height of Sand/Gravel 30 29.00 27.00 2.00 15.00 added at bottom (in):2.0 30 28.50 27.50 1.00 30.00 30 29.50 25.50 4.00 7.50 30 29.00 25.00 4.00 7.50 30 29.00 27.00 2.00 15.00 30 29.50 27.00 2.50 12.00 30 28.50 26.50 2.00 15.00 30 29.00 27.00 2.00 15.00 P1-2 31 0 23.00 23.00 0.00 Height of Sand/Gravel 30 23.00 19.00 4.00 7.50 added at bottom (in):2.0 30 23.00 21.50 1.50 20.00 30 22.50 20.00 2.50 12.00 30 23.00 21.50 1.50 20.00 30 23.00 22.00 1.00 30.00 30 23.50 21.50 2.00 15.00 30 23.00 21.50 1.50 20.00 30 23.00 21.00 2.00 15.00 P1-3 32 30 24.00 24.00 1.25 Height of Sand/Gravel 30 24.00 23.00 1.00 30.00 added at bottom (in):2.0 30 25.00 24.00 1.00 30.00 30 23.50 21.50 2.00 15.00 30 24.00 22.50 1.50 20.00 30 24.00 21.50 2.50 12.00 30 24.50 22.00 2.50 12.00 30 24.00 21.00 3.00 10.00 30 23.50 21.50 2.00 15.00 Average Percolation Rate =15.00 min/in Corrected Percolation Rate =30.00 min/in PERCOLATION TEST RESULTS Project Number: 501710003 Test Date: 9/13/2019 Project: Mulberry Connection Tested By: FT Location: Fort Collins Elevation: - +/- (MSL) Hole Number Hole Depth Time Interval Initial Water Level Height at Start Final Water Level Height at End Drop in Water Level Average Percolation Rate Time Start Time Stop (inches) (minutes) (inches) (inches) (inches) (min/in) (hh:mm) (hh:mm) P2-1 31 0 21.5 21.50 0.00 Height of Sand/Gravel 30 22 18 4.00 7.50 added at bottom (in):2.0 30 23 19.5 3.50 8.57 30 22.5 20.5 2.00 15.00 30 23 20.5 2.50 12.00 30 23 21.5 1.50 20.00 30 23.5 21 2.50 12.00 30 23 20 3.00 10.00 30 22.5 20 2.50 12.00 P2-2 33 0 24.5 24.50 0.00 Height of Sand/Gravel 30 24.5 22.5 2.00 15.00 added at bottom (in):2.0 30 25 22.5 2.50 12.00 30 25 22 3.00 10.00 30 25 22 3.00 10.00 30 24.5 22 2.50 12.00 30 25 23 2.00 15.00 30 25 22 3.00 10.00 30 25 23 2.00 15.00 P2-3 36 0 27 27.00 0.00 Height of Sand/Gravel 30 27 24.5 2.50 12.00 added at bottom (in):2.0 30 28 25.5 2.50 12.00 30 27.5 24 3.50 8.57 30 27.5 23 4.50 6.67 30 27 24 3.00 10.00 30 28 26 2.00 15.00 30 27.5 24.5 3.00 10.00 30 28 26 2.00 15.00 Average Percolation Rate =14.00 min/in Corrected Percolation Rate =28.00 min/in PERCOLATION TEST RESULTS Project Number: 501710003 Test Date: 9/13/2019 Project: Mulberry Connection Tested By: FT Location: Fort Collins Elevation: - +/- (MSL) Hole Number Hole Depth Time Interval Initial Water Level Height at Start Final Water Level Height at End Drop in Water Level Average Percolation Rate Time Start Time Stop (inches) (minutes) (inches) (inches) (inches) (min/in) (hh:mm) (hh:mm) P3-1 33 0 24.5 24.50 0.00 Height of Sand/Gravel 30 24.5 20 4.50 6.67 added at bottom (in):2.0 30 24 21.5 2.50 12.00 30 24.5 21 3.50 8.57 30 24.5 22 2.50 12.00 30 25 23.5 1.50 20.00 30 25 22.5 2.50 12.00 30 24.5 23 1.50 20.00 30 25 23.5 1.50 20.00 P3-2 30 0 22 22.00 0.00 Height of Sand/Gravel 30 22 18 4.00 7.50 added at bottom (in):2.0 30 21 18.5 2.50 12.00 30 21 20 1.00 30.00 30 22 20 2.00 15.00 30 21.5 19 2.50 12.00 30 22 21 1.00 30.00 30 22.5 21 1.50 20.00 30 22 21 1.00 30.00 P3-3 30 0 22 22.00 0.00 Height of Sand/Gravel 30 22 20 2.00 15.00 added at bottom (in):2.0 30 21.5 20.5 1.00 30.00 30 22 20.5 1.50 20.00 30 22 19.5 2.50 12.00 30 23 22 1.00 30.00 30 21.5 20 1.50 20.00 30 22 20 2.00 15.00 30 22 21 1.00 30.00 Average Percolation Rate =26.67 min/in Corrected Percolation Rate =53.33 min/in PERCOLATION TEST RESULTS Project Number: 501710003 Test Date: 9/13/2019 Project: Mulberry Connection Tested By: FT Location: Fort Collins Elevation: - +/- (MSL) Hole Number Hole Depth Time Interval Initial Water Level Height at Start Final Water Level Height at End Drop in Water Level Average Percolation Rate Time Start Time Stop (inches) (minutes) (inches) (inches) (inches) (min/in) (hh:mm) (hh:mm) P4-1 30 0 22 22.00 0.00 Height of Sand/Gravel 30 22 20 2.00 15.00 added at bottom (in):2.0 30 22 18.5 3.50 8.57 30 22.5 19.5 3.00 10.00 30 21.5 18 3.50 8.57 30 22 19.5 2.50 12.00 30 22 19.5 2.50 12.00 30 21 19 2.00 15.00 30 22 19.5 2.50 12.00 P4-2 30 0 21.5 21.50 0.00 Height of Sand/Gravel 30 21.5 18.5 3.00 10.00 added at bottom (in):2.0 30 22 18.5 3.50 8.57 30 22 20 2.00 15.00 30 23 22 1.00 30.00 30 21.5 20 1.50 20.00 30 22 20.5 1.50 20.00 30 22 20 2.00 15.00 30 22 20 2.00 15.00 P4-3 31 0 22 22.00 0.00 Height of Sand/Gravel 30 23 20 3.00 10.00 added at bottom (in):2.0 30 23 21 2.00 15.00 30 22.5 19.5 3.00 10.00 30 23 21 2.00 15.00 30 23.5 23 0.50 60.00 30 23 21 2.00 15.00 30 22.5 21 1.50 20.00 30 23 21.5 1.50 20.00 Average Percolation Rate =15.67 min/in Corrected Percolation Rate =31.33 min/in PERCOLATION TEST RESULTS 24 APPENDIX F