Loading...
HomeMy WebLinkAboutReports - Soils - 06/17/2024 STRAUSS LAKE DEVELOPMENT GROUNDWATER MONITORING REPORT PREPARED FOR: Cottonwood Land and Farms, LLC P.O. Box 229 Boulder, CO 80306 PREPARED BY. o�o,DO,t/C�� pLA/V s �i'p Anderson Consulting Engineers, Inc. V; �;0 375 East Horsetooth Road, Building 5 412 s" Fort Collins, CO 80525 (ACE Project No. COCLF10) 4NAt� June 17, 2024 ANdERSON CONSU[TINCy ENGINEERS, INC.! Civil • Water Resources • Environmental TABLE OF CONTENTS 1 Introduction.......................................................................................................................................1-1 2 Data Collection...................................................................................................................................2-1 2.1 Base Map Preparation .............................................................................................................2-1 2.2 Phase 1 Geotechnical Investigation and Groundwater Monitoring........................................2-1 2.3 Phase 2 Geotechnical Investigation and Groundwater Monitoring........................................2-3 3 Results and Conclusions.....................................................................................................................3-1 3.1 Groundwater Monitoring Results............................................................................................3-1 3.2 Groundwater Monitoring Observations and Conclusions.......................................................3-3 LIST OF FIGURES Figure1.1 Project Vicinity Map..................................................................................................................1-2 Figure 2.1 Phase 1 Groundwater Monitoring Well Locations....................................................................2-2 Figure 2.2 Phase 2 Groundwater Monitoring Well Locations North of Boxelder Ditch ............................2-4 LIST OF TABLES Table 3.1 Monitoring Well Groundwater Elevations................................................................................3-1 Table 3.2 FCRID Water Surface Elevations................................................................................................3-2 Table 3.3 Boxelder Ditch Water Surface Elevations..................................................................................3-2 Table 3.4 Pond Water Surface Elevations.................................................................................................3-3 LIST OF APPENDICES Appendix A. Data Collection Appendix A.1. Phase 1 Geotechnical Report Appendix A.2. Phase 2 Geotechnical Report Appendix A.3. Groundwater Well Locations Appendix A.4. Groundwater Monitoring Data Appendix B. Groundwater Monitoring Results Appendix B.I. Groundwater Elevation Surface Maps Strauss Lake Groundwater Monitoring Report 6-17-2024.docx i Anderson Consulting Engineers,Inc. Appendix B.2. Groundwater Elevation plots Appendix C. Digital Data Strauss Lake Groundwater Monitoring Report 6-17-2024.docx II Anderson Consii1 ing Engineers,Inc. 1 INTRODUCTION In 2018, Anderson Consulting Engineers, Inc. (ACE) was contracted by Cottonwood Land and Farms, LLC (CLF) to perform a groundwater monitoring study for a potential development site called Strauss Lake. The site,which is located in southeastern Fort Collins,Colorado, is generally bounded by Horsetooth Road on the south, Ziegler Road on the west, the Rigden Farm Outfall Channel/Great Western Railway on the north, and the Boxelder Ditch/CLF's property line on the east. A vicinity map of the project area, which encompasses approximately 183 acres, is presented on the following page as Figure 1.1. The site has had several previous land uses. The portion of the site north of the Boxelder Ditch served as an asphalt batch plant in the late 1990s and early 2000s. The asphalt batch was removed,and this portion of the site was reclaimed in 2012. Approximately 25 acres near the center portion of the site served as a concrete batch plant for numerous years. In 2021, the concrete batch plant was removed, and this area of the site was reclaimed. As part of this reclamation work, grading was conducted to the pond north of the concrete batch plant site to contour and soften the slopes of the pond. In 2014, the City of Fort Collins began construction on the adjacent Rigden Reservoir. A compacted clay liner, that was keyed into bedrock, was installed around the perimeter of the reservoir to isolate it from the groundwater table. Excavation of the reservoir resulted in the placement of several feet of granular overburden material on the Strauss Lake site south of the Boxelder Ditch. Earthwork activities were also conducted on portions of the Stauss Lake site north of the Boxelder Ditch. In this location, existing granular soils were harvested from the site for use as fill on the adjacent property where the City of Fort Collins intends to construct a regional park. Clay material from the reservoir was utilized as backfill on the Strauss Lake site north of the Boxelder Ditch. After completion of earthwork activities, groundwater began to surface in this location presumably due to the placement of clay material and construction of the reservoir liner. In 2017 and 2018, the City of Fort Collins installed an underdrain system to alleviate the surfacing of groundwater on the site. The underdrain system was installed approximately 4-feet below the ground surface and discharges via gravity into the Rigden Farm Outfall Channel near the northwestern edge of the reservoir. The alignment of this underdrain system is shown in Figure 1.1. With the proposed Strauss Lake development site bordered by two irrigation ditches and a lined water storage reservoir, the purpose of this study is twofold: 1) to determine groundwater depths across the site for future development purposes; and 2) monitor the seasonal fluctuation in groundwater levels to determine how varying water levels in the adjacent ditches impact the groundwater table. Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 1-1 Anderson Consulting Engineers,Inc. Sr F MAC%, ,(� SYST�'M WILLIAM MEAL PKWY .� 1!2 � �LL r '► PRF.V]OkTS RIGDEN RESERVOIR CO CRF-TE BATCH PIANT AREA HORS ETCOTH ROAD f' STRE4USti LAKE AREA u� Figure 1.1 Project Vicinity Map. Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 1-2 Anderson Consulting Engineers,Inc. 2 DATA COLLECTION In support of the groundwater monitoring efforts,a general data collection effort was completed. Several field reconnaissance trips were conducted to familiarize ACE staff with the project area. A preliminary plan for the conceptual site development was provided by CLF and used to identify the locations where geotechnical and groundwater information would be useful for the site development. Data collection efforts for this study were conducted in the following two phases: • Phase 1 efforts were conducted between August 2018 and May 2021 and focused on the portion of the site south of the Boxelder Ditch. • Phase 2 efforts were conducted between October 2022 and May 2024 and included the area monitored as part of Phase 1, as well as portions of the site north of the Boxelder Ditch. The subsequent sections discuss the data collection efforts conducted as part of this study. 2.1 Base Map Preparation Base mapping for the study area primarily consists of aerial imagery, parcel boundary information, and available topographic data. Aerial imagery from 2015 and 2023 were obtained from the National Agriculture Imagery Program (NAIP)database. Existing topographic data for the site was prepared by King Surveyors in 2015 as part of the Rigden Storage Reservoir as-builts. Phase 1 groundwater monitoring well locations and elevations were surveyed by AVI, P.C. (AVI) in 2018. King Surveyors conducted the survey of the Phase 2 groundwater monitoring wells in 2022. All survey and topographic information for this study is vertically referenced to the North American Vertical Datum (NAVD) of 1988 and horizontally referenced to the Colorado State Plane (north) coordinate system. Electronic copies of the base map and ground survey for the monitoring well installations are provided as digital data in Appendix C. 2.2 Phase 1 Geotechnical Investigation and Groundwater Monitoring Based on site reconnaissance, and the conceptual site development plans provided by CLF, it was decided that 18 groundwater monitoring wells would be installed across the site, south of the Boxelder Ditch, to evaluate groundwater conditions as part of Phase 1. In July 2018,CTL/Thompson (CTL)was contracted by ACE to conduct the drilling to install the temporary groundwater monitoring wells and conduct a geotechnical investigation. Locations of the groundwater monitoring wells in relation to the study area are illustrated in Figure 2.1. To evaluate subsurface soil conditions for the future development site, soil samples and logs were collected at 15 of the 18 groundwater monitoring well sites. These locations are shown in red on Figure 2.1. The borings were drilled using a truck-mounted drill rig with a 4-inch diameter, continuous flight auger. CTL's field representative was on site to log the borings and collect soil samples for laboratory testing. The borings were drilled to a minimum of 25-feet deep, or to bedrock if encountered. Upon completion of the borings, a temporary slotted PVC pipe was installed in each of the boreholes for the continued monitoring of groundwater levels. Laboratory testing of the soil samples Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 2-1 Anderson Consulting Engineers,Inc. included the determination of moisture content and dry density, swell-consolidation characteristics, Atterberg limits, particle-size analysis, and water-soluble sulfate content. Results of the Phase 1 geotechnical investigation, along with development recommendations for the portion of the site located south of the Boxelder Ditch, are provided in a report prepared by CTL titled "Geologic and Preliminary Geotechnical Investigation, Strauss Lake Development, Fort Collins, Colorado, Revised August 26, 2023". A copy of this report has been provided in Appendix A.1. LEGEND: M'VtiJ-1 M W-2 MW-1 INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING W-3 19 MW-13 INDICATES APPROXIMATE LOCATION OF PIEZOMETER _0 Figure Developed by CTL/Thompson M 0 t7C MW-8 a MW-4 MW-5 i MW-7 M -8 MW-9 MW-13 • MW-12 Mlle-11 MW-10 71 MW-15 MVV=1 i MW-16 MW-17 M'V'V-18 Hvrsetooth Road Figure 2.1 Phase 1 Groundwater Monitoring Well Locations After the Phase 1 groundwater monitoring wells were installed, ACE contracted with AVI to precisely survey the horizontal and vertical location of the top of the PVC pipe at each well. ACE staff then measured the distance from the ground surface to the top of each PVC well to obtain a ground surface elevation. To facilitate the determination of water surface elevations along the Fossil Creek Reservoir Inlet Ditch(FCRID) Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 2-2 Anderson Consulting Engineers,Inc. and the Boxelder Ditch, AVI also collected survey data on the ditch crossings adjacent to the study area. To determine water surface elevations in the pond directly north of the concrete batch plant area, ACE staff installed a staff gage on the southwestern bank of the pond and used a rod and level to establish the elevation of the 4-foot mark on the staff gage. A figure depicting the surveyed horizonal locations,top of PVC elevations, and ground surface elevations for the 18 monitoring wells installed as part of Phase 1 is provided as Sheet 1 in Appendix A.3. Sheet 1 also illustrates the locations and elevations of the ditch crossings and pond staff gage that were utilized to record water surface elevations in the ditches and pond adjacent to the study area for Phase 1. In August 2018, ACE staff began recording groundwater depths in each well by using a standard water level meter. To record groundwater depths,the probe from the water meter was lowered into a well until the probe contacted water and made a sound. Then the depth of the probe was recorded. To estimate water surface elevations in the ditches and pond,ACE staff measured down from the known elevations at the ditch crossings and staff gage locations to the water surface. ACE staff recorded groundwater, ditch water surface, and pond surface elevations once a month from August 2018 through May 2021, resulting in a 34-month data collection period. Collected data was compiled into the tabular spreadsheet for review and analysis. A pdf version of the Phase 1 spreadsheet is presented as Table A.4.1 Appendix AA and an electronic copy of the data collection spreadsheet has been provided as digital data in Appendix C. The following data collection anomalies,which are highlighted in yellow on Table A.4.1 were noted during the data collection efforts for Phase 1: • Monitoring Well #3 was installed in a sump location between the concrete batch plant and Boxelder Ditch. During periods of wet weather, water would pond above the top of the PVC well and not allow for an accurate reading. • The pond located north of the concrete batch plant would typically freeze over during the winter months, which did not allow for accurate water surface readings during this time. • In January 2021, the concrete batch plant that had operated on the site was closed and dismantled. As part of the site reclamation associated with closing the concrete batch plant, Monitoring Wells#2, #3, and #6 were either disturbed or removed completely. Therefore, no data was recorded for these wells in 2021. • In February 2021, the pond north of the previous concrete batch plant was dewatered to facilitate the reconfiguration/reshaping of the northeastern side of the pond as part of the site reclamation. Consequently, no data was recorded for pond elevations in 2021. 2.3 Phase 2 Geotechnical Investigation and Groundwater Monitoring In July 2022, CLF requested that a geotechnical investigation be performed on the portion of the site located north of the Boxelder Ditch and that additional groundwater monitoring for the entire development site be conducted. Based on updated conceptual site development plans available at that time, it was decided that 5 new monitoring wells would be installed across the site north of the Boxelder Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 2-3 Anderson Consulting Engineers,Inc. Ditch to evaluate groundwater conditions as part of Phase 2. In addition to the five new groundwater monitoring wells, it was decided that geotechnical data would also be collected at five other borehole locations. Locations of the proposed groundwater monitoring wells and geotechnical borehole locations in relation to the study area north of the Boxelder Ditch are illustrated in Figure 2.2 LEGEND: Existing BH-1 INDICATES APPROXI MATE y`T Underdrain LOCATION OF EXPLORATORY �v0 BORING ¢� MW-1 INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING WITH INSTALLEDxG MONITORING WELL Figure Developed by CTL/Thompson ¢ ' MW-26 BH-5 MW-22 B H-4 B H-3 M W-25 • BH-1 i MW-24 MW-23 • ! BH-2 0 Figure 2.2 Phase 2 Groundwater Monitoring Well Locations North of Boxelder Ditch Similar to Phase 1,ACE contracted with CTL to conduct the geotechnical investigation for Phase 2. Borings for Phase 2 were also drilled using a truck-mounted drill rig with a 4-inch diameter, continuous flight auger. CTL's field representative was on site to log the borings and collect soil samples for laboratory testing. The borings were drilled to a minimum of 25-feet deep,or to bedrock if encountered. During the drilling it was decided that slotted PVC pipe would be installed at all monitoring well and borehole locations shown in Figure 2.2 to provide additional groundwater monitoring data due to the nearby underdrain system. In addition to the new data collection locations shown in Figure 2.2, it was also decided that the three Phase 1 monitoring wells that were destroyed as part of the concrete batch plant reclamation would be reinstalled near their original locations south of the Boxelder Ditch. The reestablishment of these three wells (MW-19, MW-20, and MW-21) did not include the collection of soil samples and geotechnical testing as part of Phase 2. Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 2-4 Anderson Consulting Engineers,Inc. Laboratory testing of the soil samples for Phase 2 included the same testing as Phase 1,which determined moisture content and dry density, swell-consolidation characteristics, Atterberg limits, particle-size analysis, and water-soluble sulfate content. Results of the Phase 2 geotechnical investigation, along with development recommendations for the portion of the site located north of the Boxelder Ditch, are provided in a report prepared by CTL titled "Preliminary Geotechnical Investigation, Strauss Lake Development North — Phase 2, Ziegler Road and Drake Road, Fort Collins, Colorado, Revised August 26, 2023". A copy of this report has been provided in Appendix A.2. After the Phase 2 groundwater monitoring wells were installed, ACE contracted with King Surveyors to precisely survey the horizontal and vertical location of the top of the PVC pipe and ground elevation at each well. King Surveyors also collected survey data on the northern most ditch crossings of FCRID and Boxelder Ditch to facilitate the determination of ditch water surface elevations along the northern portion of the study area. ACE staff also installed a new staff gage on the southern bank of the pond at the center of the site to determine water surface elevations in the pond. A rod and level were used to establish the elevation of the 4-foot mark on the staff gage. A figure depicting the surveyed horizonal locations,top of PVC elevations, and ground surface elevations for all 28 wells monitored as part of Phase 2 is provided as Sheet 2 in Appendix A.3. Sheet 2 also illustrates the locations and elevations of the ditch crossings and pond staff gage that were utilized to record water surface elevations in the ditches and pond adjacent to the study area for Phase 2. In October 2022, ACE staff began recording groundwater depths in each well by using the same standard water level meter and methodology that was used for Phase 1. Water surface elevations in the ditches were recorded by measuring down to the water surface from the known elevations at the crossings and staff gage readings were used to determine water surface elevations within the pond. ACE staff recorded groundwater,ditch water surface, and pond surface elevations once a month from October 2022 through April 2024, resulting in a 19-month data collection period. Collected data was compiled into the tabular spreadsheet for review and analysis. A pdf version of the Phase 2 spreadsheet is presented as Table A.4.2 in Appendix A.4 and an electronic copy of the data collection spreadsheet has been provided as digital data in Appendix C. The following data collection anomalies,which are highlighted in yellow on Table A.4.2 were noted during the data collection efforts for Phase 2: • Between October 2022 and May 2023, groundwater levels in Monitoring Well #15 appeared to drop below the bottom elevation of the well so no readings were recorded during this time. Adequate water levels returned in June 2023. • In August 2023 Monitoring Well #21 was lost, presumably due to mowing operations. Therefore, no data was recorded for this well after July 2023. • In September 2023 Monitoring Well #9 was lost, presumably due to mowing operations. Therefore, no data was recorded for this well after August 2023. • The pond continued to freeze over during the winter months, which did not allow for accurate water surface readings during this time. Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 2-5 Anderson Consulting Engineers,Inc. 3 RESULTS AND CONCLUSIONS 3.1 Groundwater Monitoring Results Data that was collected during both phases of the monitoring program, as discussed in Section 2 and presented in Appendix A.4, was analyzed to determine the maximum, average, and minimum water surface elevations for each monitoring well and ditch/pond data collection location. Results of the data collection analyses are subsequently summarized in Tables 3.1 through 3.4. Table 3.1 Monitoring Well Groundwater Elevations. Ground Maximum Average Average Depth to Minimum Monitoring Elevation at Well Groundwater Groundwater Groundwater Groundwater Well# (ft, NAVD88) Surface Elevation Surface Elevation From Ground Surface Elevation (ft,NAVD88) (ft, NAVD88) Surface(ft) (ft,NAVD88) 1 4886.0 4876.2 4874.4 11.6 4871.8 2 4875.8 4870.9 4870.1 5.8 4869.5 3 4873.2 4870.0 4869.2 4.0 4868.6 4 4885.2 4876.5 4874.9 10.3 4874.1 5 4881.5 4872.6 4871.3 10.2 4870.5 6 4873.8 4868.5 4867.7 6.1 4867.1 7 4883.7 4876.7 4875.0 8.8 4874.4 8 4880.5 4870.9 4869.6 10.8 4869.1 9 4873.4 4867.0 4865.9 7.5 4864.9 10 4870.6 4864.8 4863.9 6.7 4863.3 11 4877.6 4868.6 4867.6 10.1 4867.1 12 4880.7 4874.7 4872.7 8.0 4872.1 13 4882.2 4877.5 4875.5 6.7 4874.8 14 4917.4 4901.1 4900.0 17.4 4899.4 15 4906.9 4901.2 4899.7 7.1 4899.0 16 4880.0 4875.2 4872.6 7.4 4871.9 17 4877.5 4869.3 4868.1 9.4 4867.8 18 4868.8 4862.1 4861.5 7.3 4861.3 19 4876.3 4868.0 4867.4 8.9 4867.1 20 4877.3 4871.6 4870.7 6.6 4869.4 21 4882.3 4873.4 4872.5 9.7 4872.1 22 4872.7 4869.6 4869.3 3.4 4869.1 Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 3-1 Anderson Consulting Engineers,Inc. Table 3.1(Continued) Monitoring Well Groundwater Elevations. Ground Maximum Average Average Depth to Minimum Monitoring Elevation at Well Groundwater Groundwater Groundwater Groundwater Well# (ft, NAVD88) Surface Elevation Surface Elevation From Ground Surface Elevation (ft, NAVD88) (ft, NAVD88) Surface(ft) (ft, NAVD88) 23 4876.4 4871.4 4871.2 5.2 4871.0 24 4880.3 4873.3 4873.2 7.1 4873.1 25 4874.2 4869.9 4869.6 4.6 4869.4 26 4873.4 4868.8 4868.7 4.8 4868.5 BH 1 4874.2 4870.1 4869.7 4.4 4869.5 BH 2 4879.6 4873.0 4872.8 6.7 4872.6 BH 3 4877.5 4873.2 4872.9 4.6 4872.6 BH 4 4873.4 4869.8 4869.5 3.9 4869.4 BH 5 4873.8 4869.7 4869.5 4.4 4869.3 Table 3.2 FCRID Water Surface Elevations. Maximum Average Minimum Location Groundwater Surface Groundwater Surface Groundwater Surface Elevation(ft,NAVD88) Elevation(ft,NAVD88) Elevation (ft, NAVD88) Headwall on Downstream 4878.3 4876.7 4876.1 Side of Environmental Drive Northeast Wingwall 4877.5 4875.7 4875.2 at William Neal Parkway Southeast Wingwall 4877.E 4875.8 4875.2 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4877.2 4874.7 4874.0 of Horsetooth Road Table 3.3 Boxelder Ditch Water Surface Elevations. Maximum Average Minimum Location Groundwater Surface Groundwater Surface Groundwater Surface Elevation(ft, NAVD88) Elevation (ft,NAVD88) Elevation (ft, NAVD88) Southeast Wingwall at 4875.4 4874.8 4874.4 Siphon Outlet Top of CMP-Upstream 4871.0 4870.2 4869.4 (Northern Crossing) Top of CMP-Downstream 4870.7 4870.0 4869.4 (Northern Crossing) Top of CMP-Upstream 4870.0 4869.0 4868.3 (Southern Crossing) Top of CMP-Downstream 4869.9 4868.9 4868.2 (Southern Crossing) Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 3-2 Anderson Consulting Engineers,Inc. Table 3.3(Continued) Boxelder Ditch Water Surface Elevations. Maximum Average Minimum Location Groundwater Surface Groundwater Surface Groundwater Surface Elevation(ft, NAVD88) Elevation(ft, NAVD88) Elevation (ft, NAVD88) Northwest Corner of Wingwall Upstream of 4863.7 4863.0 4862.0 Drop Structure Southeast Corner of Wingwall Downstream of 4863.1 4861.5 4860.8 Drop Structure Western Wall at Check Structure Adjacent to 4862.7 4861.1 4860.6 Rigden Reservoir Table 3.4 Pond Water Surface Elevations. Maximum Average Minimum Location Groundwater Surface Groundwater Surface Groundwater Surface Elevation(ft, NAVD88) Elevation (ft, NAVD88) Elevation (ft, NAVD88) Staff Gage Located In Pond 4874.9 4873.3 4871.8 As presented in Tables 3.1 through 3.4, groundwater levels varied between 4.4-feet to 0.6-feet when maximum levels are compared to minimum levels over the duration of the data collection period. Average groundwater depths varied from more than 17-feet deep to less than 4-feet deep from the existing ground surface. Data presented in Tables 3.1 through 3.4 were also utilized to develop groundwater surface maps in ACAD to inform future design efforts as the site design progress. Groundwater surface maps for the maximum, average, and minimum water surface elevations across the site are presented as Sheets B.1, B.2, and B.3, respectively, in Appendix B.1. It is noted that these maps were developed based on the assumption that groundwater and ditch levels vary linearly between data collection points. Electronic copies of the groundwater surface maps in ACAD have been provided as digital data in Appendix C. 3.2 Groundwater Monitoring Observations and Conclusions The following observations and conclusions were drawn from the results of this study: • As illustrated on the groundwater elevations plots presented in Appendix B.2, groundwater elevations appear to be directly correlated to the water depths in the adjacent ditches. When the ditches are flowing full, the groundwater elevations are at their highest. When the ditches are not flowing, groundwater elevations are at their lowest. • Groundwater elevations fluctuate seasonally,with higher elevations in the summer months and lower elevations in the winter months. Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 3-3 Anderson Consulting Engineers,Inc. • Groundwater fluctuations of up to 4.4-feet were recorded at the monitoring well locations during the data collection period. Groundwater wells located closer to the ditches experienced a higher variance of fluctuation than wells located further away from the ditches. • Due to the presence of the underdrain system, groundwater elevations fluctuated less across the portion of the property located north of the Boxelder Ditch. • The grading conducted to shape the banks of the pond located north of the previous concrete batch plant area appeared to cause a rise in pond elevations. It is assumed that the earthwork activities that were conducted to shape the pond banks reduced the permeability of the soil between the pond and the Boxelder Ditch, causing the rise in water levels. The pond levels appeared to level off during the Phase 2 data collection period. However, it is recommended that pond levels continue to be monitored as development of the site progresses and that remediation actions be taken if pond levels increase to an undesired level. • Groundwater levels may increase once the site is developed due to the irrigation of lawns and open space. • Groundwater levels should be considered in the planning and design of buildings at the site. o The existing underdrain system on the portion of the property located north of the Boxelder Ditch should be maintained in order to keep groundwater from surfacing. Below grade areas such as basements or crawlspaces are likely limited for the portion of the property located north of the Boxelder Ditch due to shallow groundwater levels and the existing underdrain system. The configuration of the existing underdrain system could be modified or extended further to the northwest, if necessary, to facilitate future development. o Construction of an underdrain system to permanently lower groundwater levels below building foundations/basements may be necessary for the portion of the site located south of the Boxelder Ditch. CTL recommends a minimum separation of 5-feet between groundwater elevations and the lowest elevation of any below-grade structure. • Groundwater levels should also be considered in the planning and design of low lying or detention pond areas at the site such that groundwater does not become exposed. Construction of an underdrain system, or impermeable pond liner, may be necessary for detention pond locations. • Additional site development and geotechnical recommendations have been provided by CTL in their reports that are attached in Appendix A.1 and A.2. Strauss Lake Groundwater Monitoring Report 6-17-2024.docx 3-4 Anderson Consulting Engineers,Inc. APPENDIX A. DATA COLLECTION APPENDIX A.1. PHASE 1 GEOTECHNICAL REPORT CTL I THOMPSON GEOLOGIC AND PRELIMINARY GEOTECHNICAL INVESTIGATION STRAUSS LAKE DEVELOPMENT FORT COLLINS, COLORADO Prepared For: ANDERSON CONSULTING ENGINEERS, INC. 375 East Horsetooth Road, Building 5 Fort Collins, Colorado 80525 Attention: Brian Smith Project No. FC08493-115 REV 5 October 1, 2018 (Revised October 8, 2018) (Revised November 6, 2018) (Revised November 7, 2018) (Revised February 20, 2023) (Revised August 26, 2023) 400 North Link Lane Fort Collins, Colorado 80524 Telephone: 970-206-9455 Fax: 970-206-9441 TABLE OF CONTENTS SCOPE................................................................................................................................ 1 SUMMARY OF CONCLUSIONS........................................................................................ 1 SITE DESCRIPTION .......................................................................................................... 2 PROPOSED DEVELOPMENT........................................................................................... 2 SITEGEOLOGY................................................................................................................. 2 GEOLOGIC HAZARDS ...................................................................................................... 3 SoftSoils ......................................................................................................................... 3 Groundwater....................................................................................................................4 Expansive Soils and Bedrock .........................................................................................4 Seismicity ........................................................................................................................4 Radioactivity.................................................................................................................... 5 FIELD AND LABORATORY INVESTIGATIONS ............................................................... 5 SUBSURFACE CONDITIONS ........................................................................................... 6 DEVELOPMENT RECOMMENDATIONS.......................................................................... 6 SiteGrading .................................................................................................................... 6 Permanent Cut and Fill Slopes....................................................................................... 7 UtilityConstruction .......................................................................................................... 7 UnderdrainSystem ......................................................................................................... 9 RetainingWalls ............................................................................................................. 10 PRELIMINARY PAVEMENT RECOMMENDATIONS ..................................................... 10 SubgradePreparation................................................................................................... 10 Preliminary Pavement Thickness Design..................................................................... 11 PRELIMINARY RECOMMENDATIONS FOR STRUCTURES........................................ 11 Foundations................................................................................................................... 11 Slabs-on-Grade and Basement Floor Construction ..................................................... 12 Below-Grade Construction............................................................................................ 12 SurfaceDrainage .......................................................................................................... 12 General Design Considerations.................................................................................... 13 WATER SOLUBLE SULFATES ....................................................................................... 13 RECOMMENDED FUTURE INVESTIGATIONS ............................................................. 14 LIMITATIONS ................................................................................................................... 14 i TABLE OF CONTENTS cont'd FIGURE 1 - LOCATIONS OF EXPLORATORY BORINGS FIGURES 2 THROUGH 4 - SUMMARY LOGS OF EXPLORATORY BORINGS FIGURE 5 - GROUNDWATER ELEVATION CONTOURS FIGURES 6 THROUGH 8 - SEWER UNDERDRAIN DETAILS APPENDIX A - LABORATORY TEST RESULTS APPENDIX B - GUIDELINE SITE GRADING SPECIFICATIONS ii SCOPE This report presents the results of our Geologic and Preliminary Geotechnical Investigation. The purpose of our investigation was to identify geologic hazards that may exist at the site and to evaluate the subsurface conditions to assist in planning and budgeting for the proposed development. The report includes descriptions of site geology, our analysis of the impact of geologic conditions on site development, a description of subsoil, bedrock, and groundwater conditions found in our exploratory borings, and discussions of site development as influenced by geotechnical considerations. The scope was described in our Service Agreement (CTL Project No. FC-18-0242) dated June 6, 2018. This report was prepared based upon our understanding of the proposed use. The recommendations are considered preliminary and can be used as guidelines for further planning of development and design of grading. We should review development and grading plans to determine if additional investigation is merited, or if we need to revise our recommendations. Additional investigations will be required to design building foundations and pavements. A summary of our findings and recommendations is presented below. More detailed discussions of the data, analysis and recommendations are presented in the report. SUMMARY OF CONCLUSIONS 1. The site contains geologic hazards that should be mitigated during planning and development. No geologic or geotechnical conditions were identified which would preclude development of this site. Shallow groundwater, expansive soils and bedrock, soft soils, and regional issues of seismicity and radioactivity are the primary geologic concerns pertaining to the development of the site. 2. The subsurface conditions encountered in our borings were variable across the site. In general, the soils and bedrock encountered in our borings consisted of 3 to 8 feet of fill over 0 to 12 feet of clayey sand or sandy clay, underlain by sand and gravel. Claystone bedrock was encountered in six of our borings at depths ranging from 17 to 23 feet below the existing ground surface. 3. Groundwater was encountered at depths ranging from 3'/2 to 12 feet below the existing ground surface. Groundwater levels will likely affect planned development at this site. A contour map of the groundwater surface is provided on Figure 5. 1 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 4. We measured consolidation and low swell in samples of clayey sand, sandy clay, and the fill. Soils exhibited compression of up to 1.5 percent and swells of up to 2.0 percent. The bedrock was not tested for swell but is judged to have a minimal influence on the proposed construction. We anticipate footing or pad- type foundations will be appropriate for most structures. Slab-on-grade floors can likely be used. 5. Asphaltic pavement sections on the order of 4 to 6 inches over aggregate base course sections of 6 inches for streets, parking areas, and access drives are anticipated for preliminary planning purposes. SITE DESCRIPTION The site is located north of Horsetooth Road and east of Ziegler Road in Fort Collins, Colorado. During our investigation, the northern portion of the site was in use as a concrete plant. The southern portion of the site was vacant during our investigation. In 2014, excess material from the construction of the adjacent water storage reservoir project was used to fill the southern portion of the site. Compaction testing of the fill was conducted by CTLIThompson. Groundcover consisted of bare soils on the northern portion of the site and natural grasses and weeds on the southern portion of the site. The eastern boundary of the site is roughly the Boxelder Ditch. The building site on the 130±acre parcel has a general slope to the southeast. The Cache La Poudre River runs southeast approximately a mile east of the site. Rigden Reservoir is located east of the site. PROPOSED DEVELOPMENT We understand the parcel is planned for development of single and/or multi-family residences. The single and multi-family residences will be 1 to 3-story, wood frame structures. Apartment structures will be 3 to 4 stories tall. Below grade areas such as basements or crawl spaces are likely but may be limited due to shallow groundwater. SITE GEOLOGY The geology of the site was investigated through review of mapping by Roger B. Colton (Geologic Map of the Boulder-Fort Collins-Greeley Area, Colorado, 1978). Our technician visited the site to assess whether field conditions are consistent with the geologic mapping and 2 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLiT PROJECT NO. FC08493-115 REV 5 reports, evaluate specific site features and to look for other geologic concerns. Geology was further evaluated through review of conditions found in exploratory borings, and our experience in the area. Referenced geologic mapping indicates the site contains primarily alluvial deposits of sand and gravel. The Upper unit of Pierre Shale was mapped as a narrow band across the southwest corner of the site and was encountered underlying the fill and alluvium. An area of eolian deposition is mapped west of the site and in the southwest corner of the site but was not encountered during drilling. GEOLOGIC HAZARDS Our investigation identified several geologic hazards that must be considered during the planning and development phases of this project. None of the geologic hazards identified will preclude development of the property. Planning should consider the geologic hazards discussed below. The hazards require mitigation which could include avoidance, non-conflicting use or engineered design and construction during site development. Geologic hazards at the site that need to be addressed include soft soils, shallow groundwater, flooding, expansive soils and bedrock, regional issues of seismicity, and radioactivity. The following sections discuss each of these geologic hazards and associated development concerns. Mitigation concepts are discussed below and in the DEVELOPMENT RECOMMENDATIONS section of the report. Soft Soils Some of the soils encountered during drilling were very loose or medium-stiff. While mitigating groundwater levels may provide some improvement in the soil conditions, areas of soft or settling soils may still be encountered. Where encountered under proposed improvements, stabilization of soft soils can likely be achieved by removal and proper recompaction or crowding 1'/2 to 3-inch nominal size crushed rock into the subsoils until the base of the excavation does not deform by more than about '/2-inch when compactive effort is applied. 3 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Groundwater Groundwater was encountered at depths of 3'/2 to 12 feet during this investigation. Groundwater is expected to fluctuate seasonally, with changing water levels in nearby water bodies, and may rise due to site development. The depth to groundwater should be evaluated during Geotechnical Investigations at the site. In general, grading should be designed to raise the elevations in areas of shallow groundwater. Construction of underdrain systems with the sanitary sewer trenches is a commonly employed method to mitigate the accumulation of shallow groundwater after construction. A minimum separation of 5 feet is desirable between the groundwater elevations and the lowest elevation of any below-grade structure. Expansive Soils and Bedrock The soils at this site include low-swelling fill and native sandy clays. Much of the bedrock formation below the site consists of claystone. Due to the depth of the bedrock and the level of groundwater above the bedrock, we believe the influence of potential swells of the bedrock will be minimal. We do not anticipate mitigation for expansive soils and bedrock will be required for the proposed construction. Seismicity This area, like most of central Colorado, is subject to a low degree of seismic risk. No indications of recent movements of any of the faults in the Larimer County area have been reported in the available geologic literature. As in most areas of recognized low seismicity, the record of the past earthquake activity in Colorado is somewhat incomplete. Based on the subsurface conditions encountered in our borings and our understanding of the geology, the site classifies as a Seismic Site Class D (2012 International Building Code). Only minor damage to relatively new, properly designed and built buildings would be expected. Wind loads, not seismic considerations, typically govern dynamic structural design in this area. 4 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Radioactivity It is normal in the Front Range of Colorado and nearby eastern plains to measure radon gas in poorly ventilated spaces in contact with soil or bedrock. Radon 222 gas is considered a health hazard and is one of several radioactive products in the chain of the natural decay of uranium into stable lead. Radioactive nuclides are common in the soils and sedimentary rocks underlying the subject site. Because these sources exist on most sites, there is potential for radon gas accumulation in poorly ventilated spaces. The amount of soil gas that can accumulate is a function of many factors, including the radio-nuclide activity of the soil and bedrock, construction methods and materials, pathways for soil gas, and existence of poorly ventilated accumulation areas. It is difficult to predict the concentration of radon gas in finished construction. During our investigation, we did not detect any radiation levels above normal background levels for the area. We recommend testing to evaluate radon levels after construction is completed. If required, typical mitigation methods for residential construction may consist of sealing soil gas entry areas and periodic ventilation of below-grade spaces and perimeter drain systems. It is relatively economical to provide for ventilation of perimeter drain systems or underslab gravel layers at the time of construction, compared to retrofitting a structure after construction. Radon rarely accumulates to significant levels in above-grade, heated, and ventilated spaces. FIELD AND LABORATORY INVESTIGATIONS Subsurface conditions were further investigated by drilling fifteen exploratory borings and three piezometers at the approximate locations shown on Figure 1. The borings and piezometers were drilled using a truck-mounted drill rig and with 4-inch diameter continuous- flight augers. Our field representative observed drilling, logged the soils found in the borings, and obtained samples. Three additional borings were drilled solely to monitor groundwater levels. Summary logs of the soils and bedrock found in the borings and field penetration resistance values are presented on Figures 2 through 4. 5 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Samples of soil and bedrock were obtained during drilling by driving a modified California-type sampler(2.5-inch O.D.) into the soils and bedrock using a 140-pound hammer falling 30 inches. Samples recovered from the borings were returned to our laboratory and visually classified by the geotechnical engineer. Laboratory testing included determination of moisture content and dry density, swell-consolidation characteristics,Atterberg limits, particle- size analysis, and water-soluble sulfate content. Laboratory test results are presented in Appendix A. SUBSURFACE CONDITIONS Subsurface conditions encountered in our borings were variable across the site. In general, the soils and bedrock encountered in our borings consisted of 3 to 8 feet of fill over 0 to 12 feet of clayey sand or sandy clay, underlain by sand and gravel. Claystone bedrock was encountered in six of our borings at 17 to 23 feet to the depths explored. Soils exhibited compression of up to 1.5 percent and swells of up to 2.0 percent. The bedrock was not tested for swell but is judged to have a minimal influence on the proposed construction. Groundwater was encountered at depths ranging from 3'/2 to 12 feet below the existing ground surface. Groundwater levels will likely affect planned development at this site. A more detailed description of the subsurface conditions is presented on our boring logs and in our laboratory testing. A map of groundwater elevation contours is presented on Figure 5. DEVELOPMENT RECOMMENDATIONS Site Grading At the time of this investigation, site grading plans were not available for review in conjunction with this subsurface exploration program. It is important that deep fills (if planned) be constructed as far in advance of surface construction as possible. It is our experience that fill compacted in accordance with the compaction recommendations in this report may settle about 1 to 2 percent of its height under its own weight. Most of this settlement usually occurs during and soon after construction. Some additional settlement is possible after development and landscape irrigation increases soil moisture. Delaying construction of structures up to one year where located on deep fills is recommended. 6 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 The existing onsite soils are suitable for re-use as fill material provided debris or deleterious organic materials are removed. The existing onsite soils are suitable for re-use as fill material provided debris or deleterious organic materials are removed. If import material is used, it should be tested and approved as acceptable fill by CTLIThompson. In general, import fill should meet or exceed the engineering qualities of the onsite soils. Prior to fill placement,all debris should be removed from fill areas and properly disposed. The ground surface in areas to be filled should be stripped of vegetation, topsoil, and other deleterious materials, scarified to a depth of at least 8 inches, moisture conditioned, and compacted as recommended below. Site grading fill should be placed in thin, loose lifts, moisture conditioned and compacted. In areas of deep fill, we recommend higher compaction criteria to help reduce settlement of the fill. The placement and compaction of fill should be observed, and density tested during construction. Compaction and moisture requirements are presented in Appendix B. Permanent Cut and Fill Slopes We recommend permanent cut and fill slopes be designed with a maximum inclination of 3:1 (horizontal to vertical). Where fills will be placed on slopes exceeding 20 percent(5:1)the slope should be benched. Structures should be setback from the top or bottom of cut and fill slopes. If site constraints (property boundaries and streets) do not permit construction with recommended slopes, we should be contacted to evaluate the subsurface soils and steeper slopes. Utility Construction We believe excavations for utility installation in the overburden soils can be performed with conventional heavy-duty trenchers or large backhoes. The excavation contractor should anticipate water in excavations. Dewatering may be accomplished by sloping excavations to occasional sumps where water can be removed by pumping. 7 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Utility trenches should be sloped or shored to meet local, State, and federal safety regulations. Based on our investigation, we believe the sand and gravel classifies as Type C soil, the clay and fill as Type B, and the bedrock classifies as Type A soil based on OSHA standards. Excavation slopes specified by OSHA are dependent upon soil types and groundwater conditions encountered. Seepage and groundwater conditions in trenches may downgrade the soil type. Contractors should identify the soils encountered in the excavation and refer to OSHA standards to determine appropriate slopes. Excavations deeper than 20 feet should be designed by a professional engineer. The width of the top of an excavation may be limited in some areas. Bracing or"trench box" construction may be necessary. Bracing systems include sheet piling, braced sheeting, and others. Lateral loads on bracing depend on the depth of excavation, slope of excavation above the bracing, surface loads, hydrostatic pressures, and allowable movement. For trench boxes and bracing allowed to move enough to mobilize the strength of the soils, with associated cracking of the ground surface, the "active" earth pressure conditions are appropriate for design. If movement is not tolerable, the "at rest" earth pressures are appropriate. We suggest an equivalent fluid density of 40 pcf for the "active" earth pressure condition and 55 pcf for the "at rest" earth pressure condition, assuming level backfill. These pressures do not include allowances for surcharge loading or for hydrostatic conditions. We are available to assist further with bracing design if desired. Water and sewer lines are usually constructed beneath paved roads. Compaction of trench backfill can have significant effect on the life and serviceability of pavements. We believe trench backfill should be placed in thin, loose lifts, and moisture conditioned to between optimum and 3 percent above optimum content for clay soils and within 2 percent of optimum moisture content for sand. Trench backfill should be compacted to at least 95 percent of maximum dry density (ASTM D 698). The placement and compaction of fill and backfill should be observed and tested by our firm during construction. If deep excavations are necessary for planned utilities, the compaction requirements provided in Appendix B. 8 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Underdrain System The use of underdrain systems below sewer mains and services is a common method to control groundwater in response to development. We recommend an underdrain system be incorporated into sanitary sewer and sewer collection systems. Underdrains should also be installed below sewer service lines to each residence planned in this area with connection to residence foundation drains. The underdrain should consist of free-draining gravel surrounding a rigid PVC pipe. The pipe should be sized for anticipated flow. Guidelines for underdrain sizing are shown in Table A. The line should consist of smooth, perforated or slotted rigid PVC pipe laid at a grade of at least 0.5 percent. A gravel cross-section of at least 2 square feet should be placed around the pipe. A positive cutoff collar (concrete) should be constructed around the sewer pipe and underdrain pipe immediately downstream of the point the underdrain pipe leaves the sewer trench. Solid pipe should be used down gradient of this collar to the daylight point. Clean-outs should be provided along the system. The entity responsible for maintenance should be identified and guidelines developed for maintenance. The underdrain should be designed to discharge to a gravity outfall provided with a permanent concrete headwall and trash rack, or to a storm sewer with a check valve to control water backing up into the underdrain system. Sewer underdrain details are shown on Figures 6 through 8. The underdrain system should be designed by a professional engineer that is licensed in the State of Colorado. Table A provides a general guideline for sizing the underdrain system. 9 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 TABLE A UNDERDRAIN SIZING Slope = 0.005 (0.5 percent) Pipe Size (inches) 4 6 8 Maximum Number of Residences 50 100 200 Slope = 0.01 (1.0 percent) Pipe Size (inches) 4 6 8 Maximum Number of Residences 75 150 300 Slope = 0.02 (2.0 percent) Pipe Size (inches) 4 6 - Maximum Number of Residences 100 300 - Note: Minimum slopes of the underdrains will govern pipe sizes and maximum number of residences serviced. Retaining Walls Site retaining walls can generally be constructed on footing foundations, however, some movement is possible for walls constructed on fill or expansive soil. Due to the preliminary status of the design process for this project, wall locations have not yet been identified. Once wall structure locations and configurations have been identified, CTLIThompson should be contacted to perform appropriate subsurface explorations and provide design recommendations. PRELIMINARY PAVEMENT RECOMMENDATIONS Subgrade Preparation Based on the borings, the near surface soils on this site will consist of low-swelling sandy clay fill. Mitigation for swell is not likely. The subgrade soils will likely be moderately to highly plastic and will provide relatively poor subgrade support below the pavements. Lime or fly ash stabilization of these soils may be recommended to improve subgrade support characteristics, in addition to enhancing the workability of the clays and reducing water infiltration into the underlying subgrade and the potential movements under the pavements. 10 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Preliminary Pavement Thickness Design Preliminary guidelines for pavement systems on this site are provided. Final pavement sections should be determined based a design level geotechnical investigation and anticipated frequency of load applications on the pavement during the desired design life. Flexible hot mixed asphaltic concrete pavement (HMAC) over Aggregate Base Course (ABC) or rigid Portland cement concrete (PCC) pavements can be used at this site for automobile and light truck traffic use. Rigid pavements are recommended in any areas subject to heavy truck traffic. We anticipate asphalt pavement sections for local residential streets will be on the order of 4 to 6 inches thick. ABC sections will be on the order of 6 inches thick. Portland cement concrete (PCC) pavement is recommended in areas subject to any heavy truck traffic such as garbage pickup and/or dumpster trucks, and any heavy delivery trucks. We anticipate the use of 5 inches of PCC for general area pavements which are not subject to truck traffic. A minimum 6-inch-thick section is anticipated in main drives and any areas subject to some moderately heavy truck traffic. Any areas subject to frequent heavy trucks should be designed based on frequency and wheel loads. PCC pavements in this area are typically reinforced due to the underlying active clays. Properly designed control joints and other joints systems are required to control cracking and allow pavement movement. PRELIMINARY RECOMMENDATIONS FOR STRUCTURES The property is currently planned for residential construction. Our field and laboratory data indicate the soil and bedrock conditions vary across the site. The following discussions are preliminary and are not intended for design or construction. After grading is completed, a detailed soils and foundation investigation should be performed. Foundations Our geologic and preliminary geotechnical investigation for this site indicates structures may be founded on shallow foundations. A design level geotechnical investigation may identify potential hazards (i.e., higher swelling soils) for specified areas not indicated by our borings which may suggest the need for a deeper foundation system or mitigation of the subgrade such as over-excavation may be recommended. 11 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Slabs-on-Grade and Basement Floor Construction The use of slab-on-grade floors for unfinished basements should be limited to areas where soils within the depth likely to influence floor performance are consolidating to low- swelling. We believe most of the lots will be rated with low risk of poor slab performance. Structurally supported floor systems should be planned in all non-basement finished living areas and where higher swelling soils are encountered. Slab performance risk should be more thoroughly defined during the design level soils and foundation investigation. Below-Grade Construction Groundwater was encountered during this investigation and will limit below-grade-areas. A separation of 5 feet is recommended between groundwater and the bottom of footings. Surface water can infiltrate and develop adjacent to foundations walls. To reduce the risk of hydrostatic pressure developing on foundation walls, foundation drains will be necessary around all below-grade areas. We suggest foundation drains be tied to the sewer underdrain system. They may also discharge to sumps where water can be removed by pumping. In our opinion, underdrain systems offer more comprehensive control of water from the foundation drain and the impact of swelling soils on foundations, slabs, and pavements. Foundation walls and grade beams should be designed to withstand lateral earth pressures. The design pressure should be established during design-level soils investigations. Surface Drainage The performance of foundations will be influenced by surface drainage. The ground surface around proposed residences should be shaped to provide runoff of surface water away from the structure and off of pavements. We generally recommend slopes of at least 12 inches in the first 10 feet where practical in the landscaping areas surrounding residences. There are practical limitations on achieving these slopes. Irrigation should be minimized to control wetting. Roof downspouts should discharge beyond the limits of backfill. Water should not be allowed to pond on or adjacent to pavements. Proper control of surface runoff is also important to limit the erosion of surface soils. Sheet flow should not be directed over unprotected slopes. Water should not be allowed to pond at the crest of slopes. Permanent slopes should be re- vegetated to reduce erosion. 12 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLiT PROJECT NO. FC08493-115 REV 5 Water can follow poorly compacted fill behind curb and gutter and in utility trenches. This water can soften fill and undermine the performance of the roadways, flatwork, and foundations. We recommend compactive effort be used in placement of all fill. General Design Considerations Exterior sidewalks and pavements supported above the onsite clays are subject to post construction movement. Flat grades should be avoided to prevent possible ponding, particularly next to the building due to soil movement. Positive grades away from the structures should be used for sidewalks and flatwork around the perimeter of the buildings in order to reduce the possibility of lifting of flatwork, resulting in ponding next to the structures. Where movement of the flatwork is objectionable, procedures recommended for slab-on-grade floors should be considered. Joints next to buildings should be thoroughly sealed to prevent the infiltration of surface water. Where concrete pavement is used,joints should also be sealed to reduce the infiltration of water. Since some post construction movement of pavement and flatwork may occur,joints around the buildings should be periodically observed and resealed where necessary. Roof drains should be discharged well away from the structures, preferably by closed pipe systems. Where roof drains are allowed to discharge on concrete flatwork or pavement areas next to the structures, care should be taken to ensure the area is as water tight as practical to eliminate the infiltration of this water next to the buildings. WATER SOLUBLE SULFATES Concrete that comes into contact with soils can be subject to sulfate attack. We measured water-soluble sulfate concentrations in four samples from this site. Concentrations were measured between 0.08 and 0.12 percent, with two samples having sulfate concentrations between 0.1 and 0.2 percent. Water-soluble sulfate concentrations between 0.1 and 0.2 percent indicate Class 1 exposure to sulfate attack, according to the American 13 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 Concrete Institute (ACI). ACI indicates adequate sulfate resistance can be achieved by using Type II cement with a water-to-cementitious material ratio of 0.50 or less. ACI also indicates concrete in Class 1 exposure environments should have a minimum compressive strength of 4,000 psi. In our experience, superficial damage may occur to the exposed surfaces of highly permeable concrete, even though sulfate levels are relatively low. To control this risk and to resist freeze-thaw deterioration,the water-to-cementitious material ratio should not exceed 0.50 for concrete in contact with soils that are likely to stay moist due to surface drainage or high- water tables. Concrete should be air entrained. RECOMMENDED FUTURE INVESTIGATIONS Based on the results of this investigation and the proposed development, we recommend the following investigations be performed: 1. Review of final site grading plans by our firm; 2. Construction testing and observation for site development; 3. Subgrade investigation and pavement design after site grading and utility installation is complete; 4. Design-level soils and foundation investigations after grading; 5. Construction testing and observation for residential building construction and paving. LIMITATIONS Our exploratory borings were located to obtain preliminary subsurface data indicative of conditions on this site. Although our borings were spaced to obtain a reasonably accurate picture of subsurface conditions, variations in the subsurface conditions not indicated in our borings are always possible. We believe this investigation was conducted in a manner consistent with that level of skill and care ordinarily used by members of the profession currently practicing under similar conditions in the locality of this project. No warranty, express or implied, is made. 14 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 This report was prepared from data developed during our field exploration, laboratory testing, engineering analysis, and experience with similar conditions. The recommendations contained in this report were based upon our understanding of the planned construction. If plans change or differ from the assumptions presented herein, we should be contacted to review our recommendations. If we can be of further service in discussing the contents of this report or in the analysis of the building and pavement from the geotechnical point of view, please call. Very truly yours, CTL THOMPSON, INC. 1 Sep 26 2023 4:26 PM John Byers R. B. "Chip" Leadbetter, PE Staff Geologist Senior Engineer 15 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO.FC08493-115 REV 5 LEGEND: DRAKE RD. APPROXIMATE cMVW-1 INDICATES APPROXIMATE SITE SCALE: 1"=600' • LOCATION OF EXPLORATORY 0' 300' 600' BORING WILLIAM NEAL p N MW-13 INDICATES APPROXIMATE PKWY. • LOCATION OF PIEZOMETERui w N HORSETOOTH RD. VICINITY MAP (FT.COLLINS,CO) NOT TO SCALE MW-1 �, MW-2 MW-3 • •y i •ry �. - 0 A a- M W-6 CID MW-4 MW-5 • IV • • MW-7 MW-8 MW-9 • • • MW-13 MW-12 MW-11 MW-10 • MW-15 MW-14 MW-16 MW-17 MW-18 Horsetooth Road Locations of Exploratory Borings ANDERSON CONSULTING ENGINEERS,INC. FIGURE 1 STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 MW-1 MW-2 MW-3 MW-4 MW-5 El. 4886.0 El. 4875.8 El. 4873.2 El. 4885.2 El. 4881.5 4,890 4,890 WC=1 21/12 4,880 DD=119 WC=11.3 4,880 SW=0.6 DD=120 SW=0.4 4112 20/12 WC=15.2 1 R9/12 DD=109 �[- WC=19.9 SW=-0.3 DD=109 SS=0.120 011SW=-0.2 4/12 14/12 6/12 W C=28.8 WC=22.6 �L WC=18.0 1 6/12 DD=95 4,870 DD=104 DD=113 SW=-0.2 4,870 SW=-0.2 SW=0.2 9/12 oa QQ0 LJ WC=15.7 11/ 50/10 LL=45 PI=25 19/1 2 2 2 35/12 -200=51 33/12 2o .6 as 0 30/12 6L-0 00 50/6 O O O- 50/12 4,860 50/6 Ld 4,860 o� LU LU w w w w LL LL g 4,850 4,850 0 w w J J w w 4,840 4,840 4,830 4,830 4,820 4,820 4,810 4,810 Summary Logs of Exploratory Borings ANDERSON CONSULTING ENGINEERS,INC. FIGURE 2 STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 MW-6 MW-7 MW-8 MW-9 MW-10 El. 4873.8 El. 4883.7 El. 4880.5 El. 4873.4 El. 4870.6 4,890 4,890 4,880 31/12iqui 4,880 WC=11.1 DD=122 SW=1.1 26/12 = 11/12 DD=115 WC=22.8 SW=0.7 DD=103 00, sW=-0.2 13/12 4,870 1 WC=19.3 4,870 1 10/12 8/12 �z DD=111 6/12 WC=18.5 WC=23.9 SW=0.1 WC=13.4 V DD=108 DD=102 DD=107 SW=0.0 SW=-0.1 1 SW=0.0 Ss=o.090 5/12 V- 14/12 4/12 =Q 24/12 1 DD=1186 WC=23.1 8/12 SW=0.5 DD=106 6L :'Q -200=41 0 50/7 � 6/12 00 4,860 a 50/12 *01 50/9 6L. DD=1105 4,860 O we=7.3 LA 44/12 SW=-o.1 a -200=8 .0 50/6 a' =Q 15/12 w . w 0 LL D LL 4 4,850 0 0 ,850 50/12 0 a > LU W W J J W W 4,840 4,840 4,830 4,830 4,820 4,820 4,810 4,810 Summary Logs of Exploratory Borings ANDERSON CONSULTING ENGINEERS,INC. FIGURE 3 STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 MW-11 MW-12 MW-15 MW-17 MW-18 El. 4877.6 El. 4880.7 El. 4906.9 El. 4877.5 El. 4868.8 LEGEND: 4,910 4,910 FILL,CLAY,SAND,GRAVEL, MOIST,STIFF TO VERY STIFF,BROWN, DARK BROWN 0 39/12 CLAY,SANDY, MOIST TO WET, MEDIUM STIFF TO STIFF, BROWN(CL) a. WC=0.9 -200=4 4,900 a'- 4,90 �L SAND,CLAYEY, MOIST TO WET, LOOSE, BROWN(SC) O SAND AND GRAVEL,CLEAN TO SLIGHTLY CLAYEY, MOIST TO WET, DENSE TO VERY Q- DENSE, BROWN,TAN, GRAY(SP,GP, GW,SW-SC,SP-SC,GP-GC) 4,890 4,89 CLAYSTONE, SANDY,WITH OCCASIONAL SANDSTONE,CLAYEY INTERBEDS, MOIST TO WET, HARD, DARK GRAY 50/6 DRIVE SAMPLE.THE SYMBOL 20/12 INDICATES 20 BLOWS OF A 140-POUND HAMMER W C=6.5 4 880 L2L004'PI=19 4 $$ FALLING 30 INCHES WERE REQUIRED TO DRIVE A 2.5-INCH O.D.SAMPLER 12 INCHES. Full 15/12 Full SZ WATER LEVEL MEASURED AT TIME OF DRILLING. WC=18.0 DD=115 20/12 SW-0.4 21/12 1 WATER LEVEL MEASURED SEVERAL DAYS AFTER DRILLING. DD=20 = 5/12 DD 25 F 4,870 ss o bao Do-9 .3 sw=2.0 4 87 F LU �s 8/12 SW=-o.2 LIJ 100, 10/12 WC=20.9 WC=21.3 LL ' DD=106 5/12 DD=107 Z z Sw=-0.1 SW=0.4 p W C=25.1 p DD=99 6/12 F > 32/12 SW=-0.1 5/12 DD 112 > WQ 5/12 DD 05$ 1 SW=o.1 4,860 WC=23.8 400 SW=-a.z 00, 4 86 w O :Q DD=382 5/12 a a sw=-0.1 8/12 we=23.9 NOTES: DD=101 O 28/12 ss-i.00 Q• 1. THE BORINGS WERE DRILLED ON JULY 30 AND 31,2018 USING 4-INCH DIAMETER �Q O 0 35/12 CONTINUOUS-FLIGHT AUGERS AND A TRUCK-MOUNTED DRILL RIG. --D 4,850 p - 4,85 2. BORING ELEVATIONS WERE SURVEYED BY A REPRESENTATIVE OF OUR FIRM REFERENCING THE TEMPORARY BENCHMARK SHOWN ON FIGURE 1. 3. THESE LOGS ARE SUBJECT TO THE EXPLANATIONS, LIMITATIONS AND CONCLUSIONS IN THIS REPORT. 4. WC _ INDICATES MOISTURE CONTENT(%). 4,840 4,84 DD _ INDICATES DRY DENSITY(PCF). SW _ INDICATES SWELL WHEN WETTED UNDER OVERBURDEN PRESSURE(%). -200_ INDICATES PASSING NO.200 SIEVE(%). LL _ INDICATES LIQUID LIMIT. PI INDICATES PLASTICITY INDEX. UC _ INDICATES UNCONFINED COMPRESSIVE STRENGTH(PSF). 4,830 4,83 SS _ INDICATES SOLUBLE SULFATE CONTENT(%). 4,820 4,820 Summary Longs of ANDERSON CONSULTING ENGINEERS,INC. Exploratory Borings STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE 4 LEGEND: DRAKE RD. APPROXIMATE i INDICATES ESTIMATED SCALE: 1"=600' i GROUNDWATER CONTOUR SITE 0' 300' 600' ELEVATION MW-1 INDICATES APPROXIMATE KWYMNEAL o • LOCATION OF EXPLORATORY W BORING OR PIEZOMETER w N (10.5) INDICATES MEASURED DEPTH T737RSETOOTH RD. TO GROUNDWATER VICINITY MAP (FT.COLLINS,CO) NOT TO SCALE (12) MW-1 MW-2 • 1 (5.5) o MW-3 N • � (3.5) c� 0 ct� / L M W-6 MW-4 MW-5 (•5) N • (10) • (11) /(9) (11) (7) BMW-13 :(AL 9.5)— MW-12 C�f;VV-I1 (6.5) (9) MW-10 MW-14 MW 16 MW-17 MW 18 (17.5) • (10.5) ` I Horsetooth Road Groundwater Elevation Contours ANDERSON CONSULTING ENGINEERS,INC. FIGURE 5 STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 Ell _z 0 w z z 0 N RESIDENCE FOUNDATION DRAIN. SANITARY 4" NON—PERFORATED SEWER CORRUGATED POLYETHYLENE PIPE (ASTM F 405). PVC SOLID UNDERDRAIN PIPE. SIZE VARIES. PVC PIPE AND FITTINGS CONFORMING TO ASTM 3034, SDR 35. MIN. : " 6" MIN. r. PROVIDE GEOTEXTILE .•sv `' .f�' - '• FABRIT BETWEEN •' ' . WASHED ROCK AND • •"`: '' ° SEWER BEDDING. .::.: ,:.,.::".:"�•::: • ; .,• .�..: .�. A. WASHED ROCK MAXIMUM SIZE: 1' •" '. %`-" ••'•4 •" � :4' " LESS THAN 3 PERCENT PASSING THE NO. 200 SIEVE. SPECIFIED TRENCH WIDTH NOTE: NOT TO SCALE. Sewer ANDERSON CONSULTING ENGINEERS, INC. U nderd ra i n STRAUSS LAKE DEVELOPMENT CTL\T Project No. FC08493-115 REV 5 Detail FIGURE 6 " 0 z 0 0 z MIN. 12" TO 18" SANITARY SEWER " (BACKHOE BUCKET WIDTH) SANITARY GRAVEL SEWER ENVELOPE BEDDING e: s.''� �.. :v,•w:•; ,�...p,.;;t{:� ,P. °P. �:.a .r� .:� . . :.• :i.°.a.' ,a. .;i.:; y;}.::•y:. :v.: a ..r a e•° .e• ..< . . d e o e e SOLID UNDERDRAIN a ' MIN. 12" PERFORATED PIPE TO OUTFALL I UNDERDRAIN LOCATION �' + PIPE POUR CONCRETE NEAT — AGAINST EXCAVATION WALL AND SANITARY SEWER BEDDING NOTE: THE CONCRETE CUTOFF WALL SHOULD EXTEND INTO THE UNDISTURBED SOILS OUTSIDE THE UNDERDRAIN AND SANITARY SEWER TRENCH A MINIMUM DISTANCE OF 12 INCHES. ANDERSON CONSULTING ENGINEERS, INC. U nderd ra i n STRAUSS LAKE DEVELOPMENT CTL\T Project No. FC08493-115 REV 5 Cutoff Wall Detail FIGURE 7 SO-UNDERDRAJN-06 GROUND SURFACE PROPOSED STREET SEWER BASEMENT EXCAVATION TRENCH SERVICE (MINIMUM 3' ABOVE BACKFILL� GROUND WATER LEVEL) FOUNDATION SANITARY DRAIN SEWER TRENCH MAIN UNDERDRAIN SERVICE VERIFY THAT ELEVATION OF UNDERDRAIN UNDERDRAIN WILL PROVIDE ADEQUATE DROP FROM FOUNDATION DRAIN TO UNDERDRAIN, PARTICULARLY WHERE DEEPER EXCAVATIONS OCCUR (WHERE STRUCTURAL FLOORS ARE PLANNED). NOT TO SCALE Conceptual ANDERSON CONSULTING ENGINEERS, INC. U nderd ra i n STRAUSS LAKE DEVELOPMENT CTL\T Project No. FC08493-115 REV 5 Service Profile FIGURE 8 APPENDIX A LABORATORY TEST RESULTS TABLE A-I: SUMMARY OF LABORATORY TEST RESULTS i I I i i i I l l EXPANSION UNDER CONSTANT r f PRESSURE DUE TO WETTING 5 I I I II I I I I I I I I I I I I I I I I I I I 4 ---._._.._.. - -- ._..__ .__..}._....�..__ .. �-I- I I I I I I I I I I I I I I I I i l l I I I I I I 3 I i i j I 2 -----------�------fi---fi--�--fi--.r--rt--;-r---------fi-----.rt.._..----t------t-----I---fit-------t------fi-----t--;--..t_._...r-;-�- ! ! -2 T-7 i i i i i i l I I I I I I I I I I I I ! I I I I ( I I I I I i t I i I I I I I I i I I I I I I I I I I I ! I I I I ( I I I I I � I j i -3 I I i l l l i l l I I I I I I I I I I i l l l i l Z r 1 II 0 -4 Qx -5 t------ l l II LU Z 0 -6 - - LU (L ' 0 I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 119 PCF From MW- 1 AT 4 FEET MOISTURE CONTENT= 13.6 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-1 i I I I i I s �- 1 I ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 5 4 � I I -........._....._......_.... I I I � I — �—I—..... I I I I I I I I I I I i t i l l I I I I I I 3 I I i j I I I I I I I I : I I I I I I I I I I I I ! I I I I I I I I I I 0 ---�- - -- _ �---I ----- - - _ ___ _ ----- - -- - - - I I I I I I I I I I 1 1 ! I I i I I III I I I I I I -2 - -- -- - - - - - - �- - -- - - j : I I � I I I I I II I I I i I I I I I I I I I I I I I I I I I I I I I z I ' 0 -4 .__�..._...... _; - - ------ --- --� -T Q I I d LU o I I I I z � I LU 1 I I, 0 () I I I I I I I I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 104 PCF From MW- 1 AT 9 FEET MOISTURE CONTENT= 20.8 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-2 i I I s �- 1 l ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 5 I I I II III I I I I I I I I I I I I I I I 4 ---._._.._.. �- -- ._..__ �._....�..__ -........._....._......_.... _..{...._...._...._....}........._.. I I I I I I I I I I I I i l l I I I I I I I 3 _ J i i i i i i i i I 2 -----------�------fi---fi--�--fi--.r--rt--;-r---------t------.rt.._..----!---�---!-----!---fit--- -------t------fi-----t--;--..t_._...r-;-�- ! ! i i i i i i l : r I I I I I I I I I I I I ! I I I I I I I I I ! !I ! ! I I I I I I I I I I I I ! I I I I I I I I I I I I I -2 i 0 Z ri 1 -4 - - -- .__�..._.... -- Z ! II W Z I I 0 -6 -- - ---- --4--...._.. -- -4. - W ! l l LL L) I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 104 PCF From MW- 1 AT 14 FEET MOISTURE CONTENT= 22.6 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-3 3 II EXPANSION UNDER CONSTANT ! z PRESSURE DUE TO WETTING I I I I I I I I I I I I I I I 1 _ - � i I I z zI x ! w - L Lift 0 2 o ! l w � ! fl! 1 0 O U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 113 PCF From MW-2 AT 4 FEET MOISTURE CONTENT= 18.0 % 3 II I EXPANSION UNDER CONSTANT z P ESSURE DUE TO WETTING I I II I j ! I � I z O o — /) z Q I I I I I I I a LLI 8-0 I I I I I I I z _O z - � I I ( I d -3 -----� - - ---- � ! I III I 1 O U it -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 120 PCF From MW-4 AT 4 FEET MOISTURE CONTEN,T1= 11.3 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-4 CTL l T PROJECT NO.FC08493-115 REV 5 3 - - ADDITIONAL UNDER CONSTANT PRESSURE DUE 2 j ! ! TO WETTING Tli I ii 1 - I I Z 0 0 ( l NIN, d w IL I 2 - ZO ! l w ! ! j O U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 109 PCF From MW-4 AT 9 FEET MOISTURE CONTENT= 19.9 % 3 ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE z TO ETTING I I II I I I : I Z : Z 0 - --�- --- --I -- ---- -- I_ t1 Lu o I Z _O z - Lu I ! --. - - ---- 3 - I II I I V O ' I -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 95 PCF From MW-5 AT 9 FEET MOISTURE CONTEN,T1= 28.8 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-5 CTL l T PROJECT NO.FC08493-115 REV 5 3 II I 2 ( ! NO MOVEMENT DUE TO WETTING I I I I I I I I I I I I I I I —L I I I I it o z 0 cl) l I l 4 Q l I w 2 - IL + a 0 _ I �! ! o ! l w i ! W F O U 4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 108 PCF From MW-6 AT 4 FEET MOISTURE CONTENT= 18.5 % 3 I I EXPANSION UNDER CONSTANT z PRESSURE DUE TO WETTING I I I I ! ! I I z ! z z Q I I I I I I I I CL o 0 I I I I I I I z _O z - � I I ( I d -3 -----� - - ---- � ! I III I 1 O U it -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 122 PCF From MW-7 AT 4 FEET MOISTURE CONTEN,T1= 11.1 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-6 CTL I T PROJECT NO.FC08493-115 REV 5 i I I I i I s �- 1 l ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 4 � I I -........._....._......_.... I I I _._ � I � I—..... I I I I I I I I I I I I I i l l I I I I I I I 3 I i i I I I I I ! I 2 - ! i i I i i i l : I I I I I I I I I I I I I I I I I ( I I I I I I I I I 0 I I I I I I I I I I I I I I I I I I I I I ( I I I I I I 2 - -- -- - - - +- - i l l "'y il I I I I I I Z ri 1 0 -4 Q II LU o I I I I Z 6 ! I I LU (L ' 0 I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 103 PCF From MW-7 AT 9 FEET MOISTURE CONTENT= 22.8 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-7 i I I I i I s �- 1 l ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 5 I I I II III I I I I I I I I I I I I I I I 4 ---._._.._.. �- -- ._..__ �._....�..__ -........._....._......_....... {...._...._...._....}........._.. .__..___...._�__._..__.. ..1.-.... l I I I I I I I I I I I I I I I i l l I I I I I I I 3 _ J I i i j I i i i i i i i i I 2 I -----------�------fi---fi--�--fi--.r--rt--;-r---------t------.rt.._..----t-------t-----I---fit--- --------t------fi-----t--;--..t_._...r-;-�- ! ! i i i i i i l : r I I I I I I I I I I I I ! I I I I I I I I I i I I : ! I i ! I I I ! I I I I i I I i l l l i II I I I I I II I I i l l l l l I I Z ........._. Z ( ! I I LU o I I I I Z 6 I I LU (L ' 0 I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 102 PCF From MW-7 AT 14 FEET MOISTURE CONTENT= 23.9 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-8 3 EXPANSION UNDER CONSTANT z ( ! PRESSURE DUE TO WETTING i I i l l i I I I I I I I i t I I I z o — ocn I j l w L z - - i l w � ! O U 4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 115 PCF From MW-8 AT 4 FEET MOISTURE CONTENT= 9.1 % 3 II I EXPANSION UNDER CONSTANT z PR SSURE DUE TO WETTING I I I I I I I I II ii z I _O o z z dLLI 8-0 j z _O z - � I I ( I a -3 -----� - - ---- � ! I III I 1 v l it I -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 111 PCF From MW-8 AT 9 FEET MOISTURE CONTEN,T1= 19.3 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-9 CTL l T PROJECT NO.FC08493-115 REV 5 3 II I 2 ( ! NO MOVEMENT DUE TO WETTING I I I I I I I I I I I I I I 0 I I I I I I I I I I I z gcn I w - L a 0 2 IL o l w � ! a F � I I O U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of SAND, CLAYEY(SC) DRY UNIT WEIGHT= 107 PCF From MW-9 AT 4 FEET MOISTURE CONTENT= 13.4 % 3 II I EXPANSION UNDER CONSTANT z P ESSURE DUE TO WETTING I I II I I ! I I I z z z a I d o I I I I I I I z _OLu z - � I I ( I d -3 -----� - - ---- � ! I III I 1 v l it I -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 118 PCF From MW- 10 AT 4 FEET MOISTURE CONTEN,T1= 14.6 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-10 CTL I T PROJECT NO.FC08493-115 REV 5 3 - - ADDITIONAL COMPRESSION T ( UNDER CONSTANT PRESSURE DUE z TO WETTING --F-T i I i l l i I I l i l I I l Hi I : , HI 1 _ - ! ! I I I I I I I I ! 0 _.—. Z —�— 0 ! I N Q 1 - x w i I i i I a 2 IL --L] o l w a F � I I O U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of SAND, CLAYEY(SC) DRY UNIT WEIGHT= 110 PCF From MW- 10 AT 9 FEET MOISTURE CONTENT= 19.5 % 3 II I EXPANSION UNDER CONSTANT z P ESSURE DUE TO WETTING I I II I I ! I I I I Z O 0 - ...- d W 8-0 I I I i I I I Z _Ouj z - � I I ( I d -3 -----� - - ---- � ! I III I 1 O I ill -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 120 PCF From MW- 11 AT 4 FEET MOISTURE CONTEN,T1= 7.1 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-11 CTL I T PROJECT NO.FC08493-115 REV 5 3 - - ADDITIONAL COMPRESSION T ( UNDER CONSTANT PRESSURE DUE z TO WETTING I I I I I I I I I I I I I I I I I 0 1 - I I z gcl) l z w 2 o ! l w � I I O U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 106 PCF From MW- 11 AT 9 FEET MOISTURE CONTENT= 20.9 % 3 I I EXPANSION UNDER CONSTANT z PRESSURE DUE TO WETTING I I ! I I ! I I z _O 0 z z CL W -- o I I I I I I I z _OLu z - � I I ( I d -3 -----� - - ---- � ! I III I 1 O I ill U ' ill -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 115 PCF From MW- 12 AT 4 FEET MOISTURE CONTEN,T1= 18.0 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-12 CTL I T PROJECT NO.FC08493-115 REV 5 i I I i i i I s �- 1 l ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 4 � I I -........._....._......_.... I I I � I - �-I-..... I I I I I I I I I I I I I i l l I I I I I I I 3 I i i j I : I I I I I I I I I I I I I I I I I ( I I I I I i I I I 0 I i I I i I I I I I I I I I I I I I I I I ( I I I I I i -2 Ti � I -3 I I i I I l i I I I I I I I I I I I I i I I l i l Z r 1 II 0 -4 - - -- .__�........ ._ ...................._.... _.._.. Qx -5 t------ -t- 14 l l II LU o I I I I Z LU (L ' 0 I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 94 PCF From MW- 12 AT 9 FEET MOISTURE CONTENT= 29.3 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-13 5 I I I I ! ! I I 4 +- 1 l ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 3 : 2 ------ ---- _........._....._......_...._ o ----------�-----fi-----r--1---fi—r--rt---;-r----------t-----.rt.._..----r--;---,�-----;--1--r--- -------t------fi-----t--; I I I i i : I I I I I I I I I I I ! I I I I I I I I I I I l i !I I I I I I I I I I I I I I I I I I I I I I I I I -3 �� i ! I i I I i I I i l l l i l l I I I I I i l l I I i l l l l l I I Z li 6 J J Q d LU c i i i i i i i Z I tp $ LU � 9 I I I I I I I I I I I I I I I I I I I I I O -10 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 99 PCF From MW- 12 AT 14 FEET MOISTURE CONTENT= 25.1 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-14 3 - - ADDITIONAL COMPRESSION T ( UNDER CONSTANT PRESSURE DUE z TO WETTING 0 I I I I I I I I I I I I I l i I _- i i I I I I I I I I i t z 0 : II I a a I I I I w 8_0 2 - g w 3 : � I I O U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 382 PCF From MW- 12 AT 19 FEET MOISTURE CONTENT= 23.8 % 3 II I EXPANSION UNDER CONSTANT z PRESSURE DUE TO WETTING I I II I I ! I I I I z z �-- z I a I i I I I I i I a W -- o I I I I I I I z _O z - F Lu d -3 -----� - - ---- � ! I III I 1 O I ill U ' ili I i -4 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 125 PCF From MW- 17 AT 4 FEET MOISTURE CONTEN,T1= 9.4 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT Test Results FIGURE A-15 CTL I T PROJECT NO.FC08493-115 REV 5 i I I I i I l l EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 5 + I I III III I I i t 111 I I I I I II I I . . .. . . ........_.. ._.........4 ---___ 3 _ J j i i j I I 2 ------------�------fi------I ---�--fi--.r--rt--;-r---------t------.rt.._..----t---�---t-----I---fit-------t------fi-----t--;--..t_._...r-;-�- i I i i I i i i i i i I I I I I I I I I I I I I I I I I I I I I ... ! I I I i I I I I I I I I I I I I I I-2 i -3 I I i l l l i II I I I I I I II I I i l l l l l Z ri 1 l 0 -4 Q ! II LU Z 0 -6 - - LU (L ' 11k I I I 0 i i i I i l i i -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 107 PCF From MW- 17 AT 9 FEET MOISTURE CONTENT= 21.3 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-16 i I i I i I s �- 1 l ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I 5 I I I II III I I I I I I I I I I I I I I I l I I I I I I I I I I I I I I I i l l I I I I I I I 3 _ J I i i j I i i i i i i i i I 2 -----------�------fi---fi--�--fi--.r--rt--;-r---------t------.rt.._..----t---�---t-----I---fit-- --------t------fi-----t--;--..t_._...r-;-�- ! ! i i i i i i l : r I I I I I I I I I I I I ! I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I I I i i ! I I I I I I I I -3 i I I i l l l i II I I I I I I II I I i l l l l l I I I I I I Z ri 0 -4 - - -- .__�..._.... ._ ...................._.... _.._.. T.__.�.. . Q II i W 5 - -- - + + --- -- --- +- 0 Z I I O -s -- - ---- -E--...._.. -- -- - - ......._... ..._...... - -i---- -I- - -- --- - - - - LU (L ' 0 I I -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 105 PCF From MW- 17 AT 14 FEET MOISTURE CONTENT= 21.8 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-17 i I i i i i I EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING I I I I I I I I I I I I I I I I I I I I I -�- I- i I I I ! I I I 3 j i i j I I 2 ------------�------ --fi--�--fi--.r--rt--;-r---------t------.rt.._..----I---�---�-----I---fit-------t------fi-----t--;--..t_._...r-;-�- : I I I I I I I I I I I I I I I I I I I I I I i I I I I I I I I I I I I I I I I I I I I i I I I I I -2 -3 — I I I I I IIII I I I I I III I I I i l l � l Z II -4 Z ( ! I I Q W -5 +- c I I Z O -s -- - ---- -E— -- - - -I---- -I- - - W (L ' 0 L) -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 112 PCF From MW- 18 AT 4 FEET MOISTURE CONTENT= 15.0 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-18 i I I I i I s �- 1 I ADDITIONAL COMPRESSION UNDER CONSTANT PRESSURE DUE TO WETTING I . .. ..+ -...._...._....._._...._.... � � - — .-4 4 ---.-__ I I I I I i l I I I i t i l l I I I I I I 3 IJ -J LI I i i j I i i i i i i t : I I I I I I I I I I I I ! I I I I I I I I I I I j I � I -2 — -j - -- - +— i -3 i I I i I I l i lI I I I I I I I I I I i I I I I I Z j II 0 -4 - - -- .__r..._... -� -----.. ._..........- Q I II LU Z O -6 -i ....I. g-4i t - I- -- --- - : LU � _ � � I I I I I I I I I I I I l l l I I I I I O L) -8 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 101 PCF From MW- 18 AT 9 FEET MOISTURE CONTENT= 23.9 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT Test Results CTL I T PROJECT NO.FC08493-115 REV 5 FIGURE A-19 HYDROMETER ANALYSIS SIEVE ANALYSIS 25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS 45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN, 1 MIN. *200 *100 *50 *40 *30 *16 *10 *8 *4 3/8" 3/4" 1'1W 3" 5"6" 8" 100 1 10 90 10 80 20 z 70 30 Z w a a 60 40 w z cr 50 50 w wof w EL 40 60 a 30 70 20 80 10 90 0 100 .001 0.002 .005 .009 .019 .037 .074 .149 .297 .590 1.19 2.0 2.38 4.76 9.52 19.1 36.1 76.2 127 200 0.42 152 DIAMETER OF PARTICLE IN MILLIMETERS SANDS GRAVEL CLAY(PLASTIC)TO SILT(NON-PLASTIC) FINE I MEDIUM ICOARSEI FINE COARSE I COBBLES Sample of GRAVEL, SANDY, SLIGHTLY CLAYEY(GP-GC) GRAVEL 49 % SAND 43 % From MW- 1 AT 19 FEET SILT&CLAY g % LIQUID LIMIT % PLASTICITY INDEX % HYDROMETER ANALYSIS SIEVE ANALYSIS 25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS 45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN. 1 MIN. *200 *100 *50 *40 *30 *16 *10 *8 *4 3/8" 314" 11/" 3" 5"6" 8" 100 1 110 90 10 80 20 0 70 30 w z z a 60 40 w z F LU 50 50 z w K U w af a 40 60 a 30 70 20 80 10 90 0 100 .001 0.002 .005 .009 .019 .037 .074 .149 .297042.590 1.19 2.0 2.38 4.76 9.52 19.1 36.1 76.2 12952200 DIAMETER OF PARTICLE IN MILLIMETERS 177 SANDS GRAVEL CLAY(PLASTIC)TO SILT(NON-PLASTIC) FINE 1COARSE1 FINE I COARSE I COBBLES Sample of SAND, GRAVELLY, SLIGHTLY CLAYEY(SP-SC) GRAVEL 22 % SAND 69 % From MW-5 AT 14 FEET SILT&CLAY 9 % LIQUID LIMIT % PLASTICITY INDEX % ANDERSON CONSULTING ENGINEERS,INC. Gradation STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 Test Results FIGURE A-20 HYDROMETER ANALYSIS SIEVE ANALYSIS 25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS 45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN, 1 MIN. *200 *100 *50 *40 *30 *16 *10 *8 *4 3/8" 3/4" 11W" 3" 5"6" 8" 100 1 10 90 10 80 20 z 70 30 Z w a a 60 40 w 00000 tr z z 0W50 50 w Uj of w EL 40 60 a 30 70 20 80 10 90 0 100 .001 0.002 .005 .009 .019 .037 .074 .149 .297 .590 1.19 2.0 2.38 4.76 9.52 19.1 36.1 76.2 127 200 0.42 152 DIAMETER OF PARTICLE IN MILLIMETERS SANDS GRAVEL CLAY(PLASTIC)TO SILT(NON-PLASTIC) FINE I MEDIUM ICOARSEI FINE I COARSE I COBBLES Sample of SAND,GRAVELLY,SLIGHTLY CLAYEY(SP-SC) GRAVEL 34 % SAND 58 % From MW-7 AT 24 FEET SILT&CLAY 8 % LIQUID LIMIT % PLASTICITY INDEX % HYDROMETER ANALYSIS SIEVE ANALYSIS 25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS 45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN. 1 MIN. *200 *100 *50 *40 *30 *16 *10 *8 *4 3/8" 3/4" 11/" 3" 5"6" 8" 100 10 90 10 80 20 0 70 30 w z Z a 60 40 w z F v 50 50 Z w U cc a 40 60 Lou 30 70 20 80 10 90 0 100 .001 0.002 .005 .009 .019 .037 .074 .149 .297042.590 1.19 2.0 2.38 4.76 9.52 19.1 36.1 76.2 12952200 DIAMETER OF PARTICLE IN MILLIMETERS 177 SANDS GRAVEL CLAY(PLASTIC)TO SILT(NON-PLASTIC) FINE 1COARSE1 FINE I COARSE I COBBLES Sample of GRAVEL, SANDY(GW) GRAVEL 69 % SAND 27 % From MW- 15 AT 4 FEET SILT&CLAY 4 % LIQUID LIMIT % PLASTICITY INDEX % ANDERSON CONSULTING ENGINEERS,INC. Gradation STRAUSS LAKE DEVELOPMENT CTL I T PROJECT NO.FC08493-115 REV 5 Test Results FIGURE A-21 Ir TABLE A-1 SUMMARY OF LABORATORY TESTING ATTERBERG LIMITS SWELL TEST RESULTS' PASSING WATER- MOISTURE DRY LIQUID PLASTICITY APPLIED SWELL NO.200 SOLUBLE DEPTH CONTENT DENSITY LIMIT INDEX SWELL* PRESSURE PRESSURE SIEVE SULFATES BORING FEET %) (PCF) (%) (PSF) (PSF % % DESCRIPTION MW-1 4 13.6 119 0.6 500 FILL,CLAY,SANDY(CL) MW-1 9 15.2 109 -0.3 1,100 0.12 CLAY,SANDY(CL) MW-1 14 22.6 104 -0.2 1,800 CLAY,SANDY(CL) MW-1 19 4.2 8 GRAVEL,SANDY,SLIGHTLY CLAYEY(GP-GC) MW-2 4 18.0 113 0.2 500 CLAY,SANDY(CL) MW-3 4 15.7 45 25 51 FILL,CLAY,SANDY(CL) MW-4 4 11.3 120 0.4 500 IFILL,CLAY,SANDY(CL) MW-4 9 19.9 109 -0.2 1,100 CLAY,SANDY(CL) MW-5 9 28.8 95 -0.2 1,100 CLAY,SANDY CL MW-5 14 11.6 9 SAND,GRAVELLY,SLIGHTLY CLAYEY SP-SC) MW-6 4 18.5 108 0.0 500 0.09 FILL,CLAY,SANDY(CL) MW-6 9 23.1 106 41 SAND,CLAYEY(SC) MW-7 4 11.1 122 1.1 500 FILL,CLAY,SANDY(CL) MW-7 9 22.8 103 -0.2 1,100 CLAY,SANDY CL MW-7 14 23.9 102 -0.1 1,800 CLAY,SANDY(CL) MW-7 24 7.3 8 SAND,GRAVELLY,SLIGHTLY CLAYEY(SP-SC) MW-8 4 9.1 115 0.7 500 FILL,CLAY,SANDY CL MW-8 9 19.3 111 0.1 1,100 CLAY,SANDY(CL) MW-9 4 13.4 107 0.0 500 SAND,CLAYEY SC MW-10 4 14.6 118 0.5 500 ICLAY,SANDY(CL) MW-10 9 19.5 110 -0.1 1,100 SAND,CLAYEY(SC) MW-11 4 7.3 120 0.2 500 0.08 FILL,CLAY,SANDY(CL) MW-11 9 20.9 106 -0.1 1,100 CLAY,SANDY(CL) MW-12 4 18.0 115 0.4 500 1,300 FILL,CLAY,SANDY(CL) MW-12 9 29.3 94 -0.2 1,100 CLAY,SANDY CL MW-12 14 25.1 99 -0.1 1,800 CLAY,SANDY(CL) MW-12 19 23.8 382 -0.1 2,400 CLAY,SANDY CL MW-15 4 0.9 4 GRAVEL,SANDY(GW) MW-15 24 6.5 42 19 17 SANDSTONE,CLAYEY MW-17 4 9.4 125 2.0 500 FILL,CLAY,SANDY(CL) MW-17 9 21.3 107 0.4 1,100 2,000 CLAY,SANDY CL MW-17 14 21.8 105 -0.2 1,800 CLAY,SANDY(CL) MW-18 4 15.0 112 0.1 500 1,000 IFILL,CLAY,SANDY CL MW-18 9 23.9 101 -1.5 1,100 1 0.10 ICLAY,SANDY(CL) *NEGATIVE VALUE INDICATES COMPRESSION. ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO.FC08493-115 REV 5 Page 1 of 1 APPENDIX B GUIDELINE SITE GRADING SPECIFICATIONS GUIDELINE SITE GRADING SPECIFICATIONS 1. DESCRIPTION This item shall consist of the excavation, transportation, placement and compaction of materials from locations indicated on the plans, or staked by the Engineer, as necessary to achieve preliminary street and overlot elevations. These specifications shall also apply to compaction of excess cut materials that may be placed outside of the development boundaries. 2. GENERAL The Soils Engineer shall be the Owner's representative. The Soils Engineer shall approve fill materials, method of placement, moisture contents and percent compaction, and shall give written approval of the completed fill. 3. CLEARING JOB SITE The Contractor shall remove all vegetation and debris before excavation or fill placement is begun. The Contractor shall dispose of the cleared material to provide the Owner with a clean, neat appearing job site. Cleared material shall not be placed in areas to receive fill or where the material will support structures of any kind. 4. SCARIFYING AREA TO BE FILLED All topsoil and vegetable matter shall be removed from the ground surface upon which fill is to be placed. The surface shall then be plowed or scarified until the surface is free from ruts, hummocks or other uneven features, which would prevent uniform compaction. 5. COMPACTING AREA TO BE FILLED After the foundation for the fill has been cleared and scarified, it shall be disked or bladed until it is free from large clods, brought to the proper moisture content(0 to 3 percent above optimum moisture content for clays and within 2 percent of optimum moisture content for sands) and compacted to not less than 95 percent of maximum dry density as determined in accordance with ASTM D698. 6. FILL MATERIALS Fill soils shall be free from organics, debris, or other deleterious substances, and shall not contain rocks or lumps having a diameter greater than six (6) inches. Fill materials shall be obtained from cut areas shown on the plans or staked in the field by the Engineer. ANDERSON CONSULTING ENGINEERS, INC. B_1 STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 On-site materials classifying as CL, CH, SC, SM, SW, SP, GP, GC, and GM are acceptable. Concrete, asphalt, organic matter and other deleterious materials or debris shall not be used as fill. 7. MOISTURE CONTENT AND DENSITY Fill material shall be moisture conditioned and compacted to the criteria in the table, below. Maximum density and optimum moisture content shall be determined from the appropriate Proctor compaction tests. Sufficient laboratory compaction tests shall be made to determine the optimum moisture content for the various soils encountered in borrow areas. FILL COMPACTION AND MOISTURE REQUIREMENTS Soil Depth from Moisture Requirement Final Grade Density Requirement Type (feet) (% from optimum) Clay 0 to 15 feet 0 to +3 95% of ASTM D 698 Sand -2 to +2 95% of ASTM D 698 Clay Greater than 15 -2 to +1 98% of ASTM D 698 F§a feet -2 to +1 95% of ASTM D 1557 The Contractor may be required to add moisture to the excavation materials in the borrow area if, in the opinion of the Soils Engineer, it is not possible to obtain uniform moisture content by adding water on the fill surface. The Contractor may be required to rake or disc the fill soils to provide uniform moisture content through the soils. The application of water to embankment materials shall be made with any type of watering equipment approved by the Soils Engineer, which will give the desired results. Water jets from the spreader shall not be directed at the embankment with such force that fill materials are washed out. Should too much water be added to any part of the fill, such that the material is too wet to permit the desired compaction from being obtained, rolling and all work on that section of the fill shall be delayed until the material has been allowed to dry to the required moisture content. The Contractor will be permitted to rework wet material in an approved manner to hasten its drying. ANDERSON CONSULTING ENGINEERS, INC. B-2 STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 8. COMPACTION OF FILL AREAS Selected fill material shall be placed and mixed in evenly spread layers. After each fill layer has been placed, it shall be uniformly compacted to not less than the specified percentage of maximum density. Fill shall be compacted to the criteria above. At the option of the Soils Engineer, soils classifying as SW, GP, GC, or GM may be compacted to 95 percent of maximum density as determined in accordance with ASTM D 1557 or 70 percent relative density for cohesionless sand soils. Fill materials shall be placed such that the thickness of loose materials does not exceed 12 inches and the compacted lift thickness does not exceed 6 inches. Compaction as specified above, shall be obtained by the use of sheepsfoot rollers, multiple-wheel pneumatic-tired rollers, or other equipment approved by the Engineer for soils classifying as CL, CH, or SC. Granular fill shall be compacted using vibratory equipment or other equipment approved by the Soils Engineer. Compaction shall be accomplished while the fill material is at the specified moisture content. Compaction of each layer shall be continuous over the entire area. Compaction equipment shall make sufficient trips to ensure that the required density is obtained. 9. COMPACTION OF SLOPES Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction operations shall be continued until slopes are stable, but not too dense for planting, and there is not appreciable amount of loose soils on the slopes. Compaction of slopes may be done progressively in increments of three to five feet(3'to 5') in height or after the fill is brought to its total height. Permanent fill slopes shall not exceed 3:1 (horizontal to vertical). 10. PLACEMENT OF FILL ON NATURAL SLOPES Where natural slopes are steeper than 20 percent in grade and the placement of fill is required, benches shall be cut at the rate of one bench for each 5 feet in height (minimum of two benches). Benches shall be at least 10 feet in width. Larger bench widths may be required by the Engineer. Fill shall be placed on completed benches as outlined within this specification. ANDERSON CONSULTING ENGINEERS, INC. B-3 STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 11. DENSITY TESTS Field density tests shall be made by the Soils Engineer at locations and depths of his choosing. Where sheepsfoot rollers are used, the soil may be disturbed to a depth of several inches. Density tests shall be taken in compacted material below the disturbed surface. When density tests indicate that the density or moisture content of any layer of fill or portion thereof is not within specification, the particular layer or portion shall be reworked until the required density or moisture content has been achieved. 12. SEASONAL LIMITS No fill material shall be placed, spread, or rolled while it is frozen, thawing, or during unfavorable weather conditions. When work is interrupted by heavy precipitation, fill operations shall not be resumed until the Soils Engineer indicates that the moisture content and density of previously placed materials are as specified. 13. NOTICE REGARDING START OF GRADING The Contractor shall submit notification to the Soils Engineer and Owner advising them of the start of grading operations at least three (3) days in advance of the starting date. Notification shall also be submitted at least 3 days in advance of any resumption dates when grading operations have been stopped for any reason other than adverse weather conditions. 14. REPORTING OF FIELD DENSITY TESTS Density tests made by the Soils Engineer, as specified under"Density Tests" above, shall be submitted progressively to the Owner. Dry density, moisture content, and percentage compaction shall be reported for each test taken. 15. DECLARATION REGARDING COMPLETED FILL The Soils Engineer shall provide a written declaration stating that the site was filled with acceptable materials and was placed in general accordance with the specifications. ANDERSON CONSULTING ENGINEERS, INC. B_4 STRAUSS LAKE DEVELOPMENT CTLIT PROJECT NO. FC08493-115 REV 5 APPENDIX A.2. PHASE 2 GEOTECHNICAL REPORT CTLITHOMPSON • PRELIMINARY GEOTECHNICAL INVESTIGATION Strauss Lake Development North — Phase 2 Ziegler Road and Drake Road Fort Collins, Colorado Prepared for: Anderson Consulting Engineers, Inc. 375 East Horsetooth Road, Building 5 For Collins, Colorado 80525 Attention: Brian Smith Project No. FC08493.002-115 November 16, 2022 (Revised February 20, 2023) (Revised August 26, 2023) CTLIThompson, Inc. Denver, Fort Collins, Colorado Springs, Glenwood Springs, Pueblo, Summit County—Colorado Cheyenne, Wyoming and Bozeman, Montana Table of Contents Scope.............................................................................................................................................. 1 SummaryOf Conclusions............................................................................................................... 1 Site Description and Proposed Construction ................................................................................. 2 PreviousInvestigation..................................................................................................................... 2 SiteGeology.................................................................................................................................... 2 GeologicHazards ........................................................................................................................... 3 SoftSoils ..................................................................................................................................... 3 Groundwater................................................................................................................................ 3 Expansive Soils and Bedrock .....................................................................................................4 Seismicity ....................................................................................................................................4 Radioactivity................................................................................................................................4 Field And Laboratory Investigations............................................................................................... 5 SubsurfaceConditions.................................................................................................................... 5 Development Recommendations ................................................................................................... 6 SiteGrading ................................................................................................................................ 6 Permanent Cut and Fill Slopes................................................................................................... 6 UtilityConstruction ...................................................................................................................... 7 UnderdrainSystem ..................................................................................................................... 8 RetainingWalls ........................................................................................................................... 9 Preliminary Pavement Recommendations..................................................................................... 9 SubgradePreparation................................................................................................................. 9 Preliminary Pavement Thickness Design ................................................................................... 9 Preliminary Recommendations for Structures.............................................................................. 10 Foundations and Floor Systems............................................................................................... 10 Below-Grade Construction........................................................................................................ 10 SurfaceDrainage ...................................................................................................................... 11 General Design Considerations................................................................................................ 11 WaterSoluble Sulfates.............................................................................................................. 12 Recommended Future Investigations........................................................................................... 13 Limitations..................................................................................................................................... 13 FIGURE 1 — LOCATIONS OF EXPLORATORY BORINGS FIGURE 2 — GROUNDWATER ELEVATION CONTOURS FIGURES 3 AND 4 — SUMMARY LOGS OF EXPLORATORY BORINGS FIGURES 5 THROUGH 7—SEWER UNDERDRAIN DETAILS APPENDIX A— LABORATORY TEST RESULTS APPENDIX B — GUIDELINE SITE GRADING SPECIFICATIONS i Scope This report presents the results of our Geologic and Preliminary Geotechnical Investigation. The purpose of our investigation was to identify geologic hazards that may exist at the site and to evaluate the subsurface conditions to assist in planning and budgeting for the proposed development. The report includes descriptions of site geology, our analysis of the impact of geologic conditions on site development, a description of subsoil, bedrock, and groundwater conditions found in our exploratory borings, and discussions of site development as influenced by geotechnical considerations. The scope was described in our Service Agreement(CTLIT Proposal No. FC-22-0387) dated August 23, 2022. This report was prepared based upon our understanding of the development plans. The recommendations are considered preliminary and can be used as guidelines for further planning of development and design of grading. We should review final development and grading plans to determine if additional investigation is merited, or if we need to revise our recommendations. Additional investigations will be required to design building foundations and pavements. A summary of our findings and recommendations is presented below. More detailed discussions of the data, analysis, and recommendations are presented in the report. Summary Of Conclusions 1. The site contains geologic hazards that should be mitigated during planning and development. No geologic or geotechnical conditions were identified which would preclude development of this site. Shallow groundwater, expansive soils and bedrock, soft soils, and regional issues of seismicity and radioactivity are the primary geologic concerns pertaining to the development of the site. 2. The subsurface conditions encountered in our borings were variable across the site. In general, the soils encountered in our borings consisted of 6 to 14 feet of fill over clayey sand, sandy clay, or gravelly sand. Claystone bedrock was encountered in all of our borings at 13 to 23 feet to the depths explored. 3. Groundwater was encountered at depths ranging from 3'/2 to 7'/z feet below the existing ground surface. Groundwater levels will likely affect planned development at this site. 4. Our geologic and preliminary geotechnical investigation for this site indicates structures will likely require deep foundations with crawlspaces. Deep foundations are likely due to the soft, undocumented fill as well as the depth to groundwater. 5. Hot mix asphalt pavement sections on the order of 4 to 6 inches over aggregate base course sections of 6 inches for streets, parking areas, and access drives are anticipated for preliminary planning purposes. 1 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Site Description and Proposed Construction The site is located southeast of Drake Road and Ziegler Road in Fort Collins, Colorado. During our investigation, the site was vacant. Boxelder Ditch is located along the southern edge of the site. Rigden Reservoir is located to the southeast. We understand soils from the project site had been partially excavated and used to build up a future park site for the City of Fort Collins locate east of the site. The project site was later brought up to current grades with excess material from the construction of the adjacent water storage reservoir project. No compaction testing was completed on the fill. After the fill was placed, groundwater began to rise at the site and an underdrain system was installed. We understand the owner is considering single and multi-family units 1 to 3 stories tall and apartments 3 to 4 stories tall. Below grade areas such as basements or crawl spaces are likely limited in this area unless final grade is raised to meet the proper separation from footings to the shallow groundwater. Previous Investigation CTLIThompson previously performed a Geologic and Preliminary Geotechnical Investigation (Project No. FC08493-115, report revised November 7, 2018) for Phase 1 of the Strauss Lake Development located south of Phase 2. The data generated from this investigation was reviewed in preparation of this report. Site Geology The geology of the site was investigated through review of mapping by Roger B. Colton (Geologic Map of the Boulder-Fort Collins-Greeley Area, Colorado, 1978). Our technician visited the site to assess whether field conditions are consistent with the geologic mapping and reports, evaluate specific site features, and to look for other geologic concerns. Geology was further evaluated through review of conditions found in exploratory borings,and our experience in the area. Referenced geologic mapping indicates the site contains primarily alluvial deposits of sand and gravel. The Upper unit of Pierre Shale was mapped as a narrow band to the west and south of the site, and was encountered underlying the fill and alluvium. An area of eolian deposition is mapped west of the site and in the south of the site, but was not encountered during drilling. 2 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Geologic Hazards Our investigation identified several geologic hazards that must be considered during the planning and development phases of this project. None of the geologic hazards identified will preclude development of the property. Planning should consider the geologic hazards discussed below. The hazards require mitigation which could include avoidance, non-conflicting use or engineered design and construction during site development. Geologic hazards at the site that need to be addressed include soft soils, shallow groundwater, expansive soils and bedrock, and regional issues of seismicity and radioactivity. The following sections discuss each of these geologic hazards and associated development concerns. Mitigation concepts are discussed below and in the DEVELOPMENT RECOMMENDATIONS section of the report. Soft Soils Some of the soils encountered during drilling were soft. The soft soils are generally existing fill. The fill was never tested for compaction when it was placed. Where encountered under proposed improvements, stabilization of soft soils can likely be achieved by removal and proper recompaction or crowding 11/2 to 3-inch nominal size crushed rock into the subsoils until the base of the excavation does not deform by more than about '/2-inch when compactive effort is applied. Groundwater Groundwater was encountered at depths of 3'/2 to 7'/2 feet during this investigation. Groundwater is expected to fluctuate seasonally,with changing water levels in nearby water bodies, and may rise due to site development. The depth to groundwater should be evaluated during Geotechnical Investigations at the site. In general, grading should be designed to raise the elevations in areas of shallow groundwater. Construction of underdrain systems with the sanitary sewer trenches is a commonly employed method to mitigate the accumulation of shallow groundwater after construction. A minimum separation of 5 feet is desirable between the groundwater elevations and the lowest elevation of any below-grade structure. Below grade structures may be limited. 3 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Expansive Soils and Bedrock The soils at this site include low-swelling fill and native sandy clays. Much of the bedrock formation below the site consists of claystone. Due to the depth of the bedrock and the level of groundwater above the bedrock, we believe the influence of potential swells of the bedrock will be minimal. We do not anticipate mitigation for expansive soils and bedrock will be required for the proposed construction. Seismicity This area, like most of central Colorado, is subject to a low degree of seismic risk. No indications of recent movements of any of the faults in the Larimer County area have been reported in the available geologic literature. As in most areas of recognized low seismicity, the record of the past earthquake activity in Colorado is somewhat incomplete. Based on the subsurface conditions encountered in our borings and our understanding of the geology, the site classifies as a Seismic Site Class D (2012 International Building Code). Only minor damage to relatively new, properly designed and built buildings would be expected. Wind loads, not seismic considerations, typically govern dynamic structural design in this area. Radioactivity It is normal in the Front Range of Colorado and nearby eastern plains to measure radon gas in poorly ventilated spaces in contact with soil or bedrock. Radon 222 gas is considered a health hazard and is one of several radioactive products in the chain of the natural decay of uranium into stable lead. Radioactive nuclides are common in the soils and sedimentary rocks underlying the subject site. Because these sources exist on most sites, there is potential for radon gas accumulation in poorly ventilated spaces. The amount of soil gas that can accumulate is a function of many factors, including the radio-nuclide activity of the soil and bedrock, construction methods and materials, pathways for soil gas and existence of poorly ventilated accumulation areas. It is difficult to predict the concentration of radon gas in finished construction. 4 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 During our investigation, we did not detect any radiation levels above normal background levels for the area. We recommend testing to evaluate radon levels after construction is completed. If required, typical mitigation methods for residential construction may consist of sealing soil gas entry areas and periodic ventilation of below-grade spaces and perimeter drain systems. It is relatively economical to provide for ventilation of perimeter drain systems or underslab gravel layers at the time of construction, compared to retrofitting a structure after construction. Radon rarely accumulates to significant levels in above-grade, heated and ventilated spaces. Field And Laboratory Investigations Subsurface conditions were further investigated by drilling five exploratory borings and installing temporary piezometers at the approximate locations shown on Figure 1. The borings were drilled using a truck-mounted drill rig with 4-inch diameter continuous-flight augers. Our field representative observed drilling, logged the soils found in the borings, and obtained samples. Summary logs of the soils found in the borings and field penetration resistance values are presented on Figures 3 and 4 Samples of soil and bedrock were obtained during drilling by driving a modified California- type sampler (2.5-inch O.D.) into the subsoils and bedrock using a 140-pound hammer falling 30 inches. Samples recovered from the test holes were returned to our laboratory and visually classified by the geologist/ geotechnical engineer. Laboratory testing included determination of moisture content and dry density, swell-consolidation characteristics,Atterberg limits, particle-size analysis, and water-soluble sulfate content. Laboratory test results are presented in Appendix A. Subsurface Conditions The subsurface conditions encountered in our borings were variable across the site. In general, the soils encountered in our borings consisted of 6 to 14 feet of fill over clayey sand,sandy clay, or gravelly sand. Claystone bedrock was encountered in all of our borings at 13 to 23 feet to the depths explored. Samples of the soils and bedrock tested exhibited nil to 2.6 percent swell. Groundwater levels will likely affect planned development at this site. A more detailed description of the subsurface conditions is presented on our boring logs and in our laboratory testing. 5 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Development Recommendations Site Grading At the time of this investigation, site grading plans were not available for review in conjunction with this subsurface exploration program. Based on conversations with the developer, we understand site grading will be limited to fills of about 2 to 3 feet. Although not currently planned, it is important that deep fills be constructed as far in advance of surface construction as possible. It is our experience that fill compacted in accordance with the compaction recommendations in this report may settle about 1 to 2 percent of its height under its own weight. Most of this settlement usually occurs during and soon after construction. Some additional settlement is possible after development and landscape irrigation increases soil moisture. Delaying construction of structures up to one year where located on deep fills is recommended. The existing onsite soils are suitable for re-use as fill material provided debris or deleterious organic materials are removed. The existing onsite soils are suitable for re-use as fill material provided debris or deleterious organic materials are removed. If import material is used, it should be tested and approved as acceptable fill by CTLIThompson. In general, import fill should meet or exceed the engineering qualities of the onsite soils. Prior to fill placement, all debris should be removed from fill areas and properly disposed. The ground surface in areas to be filled should be stripped of vegetation, topsoil, and other deleterious materials, scarified to a depth of at least 8 inches, moisture conditioned and compacted as recommended below. Site grading fill should be placed in thin, loose lifts, moisture conditioned and compacted. In areas of deep fill, we recommend higher compaction criteria to help reduce settlement of the fill. The placement and compaction of fill should be observed, and density tested during construction. Compaction and moisture requirements are presented in Appendix B. Permanent Cut and Fill Slopes We recommend permanent cut and fill slopes be designed with a maximum inclination of 3:1 (horizontal to vertical). Where fills will be placed on slopes exceeding 20 percent (5:1) the slope should be benched. Structures should be setback from the top or bottom of cut and fill slopes. If site constraints (property boundaries and streets) do not permit construction with recommended slopes, we should be contacted to evaluate the subsurface soils and steeper slopes. 6 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Utility Construction We believe excavations for utility installation in the overburden soils can be performed with conventional heavy-duty trenchers or large backhoes. The excavation contractor should anticipate water in excavations. Dewatering may be accomplished by sloping excavations to occasional sumps where water can be removed by pumping. Utility trenches should be sloped or shored to meet local, State, and federal safety regulations. Based on our investigation, we believe the sand and gravel classifies as Type C soil, the clay and fill as Type B, and the bedrock classifies as Type A soil based on OSHA standards. Excavation slopes specified by OSHA are dependent upon soil types and groundwater conditions encountered. Seepage and groundwater conditions in trenches may downgrade the soil type. Contractors should identify the soils encountered in the excavation and refer to OSHA standards to determine appropriate slopes. Excavations deeper than 20 feet should be designed by a professional engineer. The width of the top of an excavation may be limited in some areas. Bracing or"trench box" construction may be necessary. Bracing systems include sheet piling, braced sheeting,and others. Lateral loads on bracing depend on the depth of excavation,slope of excavation above the bracing, surface loads, hydrostatic pressures, and allowable movement. For trench boxes and bracing allowed to move enough to mobilize the strength of the soils,with associated cracking of the ground surface, the "active" earth pressure conditions are appropriate for design. If movement is not tolerable, the"at rest"earth pressures are appropriate. We suggest an equivalent fluid density of 40 pcf for the "active" earth pressure condition and 55 pcf for the "at rest" earth pressure condition, assuming level backfill. These pressures do not include allowances for surcharge loading or for hydrostatic conditions. We are available to assist further with bracing design if desired. Water and sewer lines are usually constructed beneath paved roads. Compaction of trench backfill can have significant effect on the life and serviceability of pavements. We believe trench backfill should be placed in thin, loose lifts, and moisture conditioned to between optimum and 3 percent above optimum content for clay soils and within 2 percent of optimum moisture content for sand. Trench backfill should be compacted to at least 95 percent of maximum dry density(ASTM D 698). The placement and compaction of fill and backfill should be observed and tested by our firm during construction. If deep excavations are necessary for planned utilities, the compaction requirements provided in Appendix B. 7 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Underdrain System Although there is already an underdrain system at this site, the use of underdrain systems below sewer mains and services is a common method to control groundwater in response to development. We recommend an underdrain system be incorporated into sanitary sewer and sewer collection systems. Underdrains should also be installed below sewer service lines to each residence planned in this area with connection to residence foundation drains. The underdrain should consist of free-draining gravel surrounding a rigid PVC pipe. The pipe should be sized for anticipated flow. Guidelines for underdrain sizing are shown in Table A. The line should consist of smooth, perforated or slotted rigid PVC pipe laid at a grade of at least 0.5 percent. A gravel cross-section of at least 2 square feet should be placed around the pipe. A positive cutoff collar(concrete) should be constructed around the sewer pipe and underdrain pipe immediately downstream of the point the underdrain pipe leaves the sewer trench. Solid pipe should be used down gradient of this collar to the daylight point. Clean-outs should be provided along the system. The entity responsible for maintenance should be identified and guidelines developed for maintenance. The underdrain should be designed to discharge to a gravity outfall provided with a permanent concrete headwall and trash rack, or to a storm sewer with a check valve to control water backing up into the underdrain system. Sewer underdrain details are shown on Figures 5 through 7. The underdrain system should be designed by a professional engineerthat is licensed in the State of Colorado. Table A provides a general guideline for sizing the underdrain system. TABLE A UNDERDRAIN SIZING Slope = 0.005 (0.5 percent) Pipe Size (inches) 4 6 8 Maximum Number of Residences 50 100 200 Slope = 0.01 (1.0 percent) Pipe Size (inches) 4 6 8 Maximum Number of Residences 75 150 300 Slope = 0.02 (2.0 percent) Pipe Size (inches) 4 6 - Maximum Number of Residences 100 300 - Note: Minimum slopes of the underdrains will govern pipe sizes and maximum number of residences serviced. 8 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Retaining Walls Site retaining walls can generally be constructed on footing foundations, however, some movement is possible for walls constructed on fill or expansive soil. Due to the preliminary status of the design process for this project, wall locations have not yet been identified. Once wall structure locations and configurations have been identified, CTLIThompson should be contacted to perform appropriate subsurface explorations and provide design recommendations. Preliminary Pavement Recommendations Subgrade Preparation Based on the borings, the near surface soils on this site will consist of low swelling sandy clay fill. Mitigation for swell is not likely; however, the upper soils are comprised of uncompacted, soft fill that will likely need mitigation. The subgrade soils will be moderately to highly plastic and will provide relatively poor subgrade support below the pavements. Lime or fly ash stabilization of these soils may be recommended to improve subgrade support characteristics, in addition to enhancing the workability of the clays and reducing water infiltration into the underlying subgrade and the potential movements under the pavements. Preliminary Pavement Thickness Design Preliminary guidelines for pavement systems on this site are provided. Final pavement sections should be determined based a design level geotechnical investigation and anticipated frequency of load applications on the pavement during the desired design life. Flexible hot mixed asphaltic pavement (HMA) over aggregate base course (ABC) or rigid Portland cement concrete (PCC)pavements can be used at this site for automobile and light truck traffic use. Rigid pavements are recommended in any areas subject to heavy truck traffic. We anticipate asphalt pavement sections for local residential streets will be on the order of 4 to 6 inches thick. ABC sections will be on the order of 6 inches thick. Portland cement concrete(PCC)pavement is recommended in areas subject to any heavy truck traffic such as garbage pickup and/or dumpster trucks and any heavy delivery trucks. We anticipate the use of 5 inches of PCC for general area pavements which are not subject to truck 9 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 traffic. A minimum 6-inch-thick section is anticipated in main drives and any areas subject to some moderately heavy truck traffic. Any areas subject to frequent heavy trucks should be designed based on frequency and wheel loads. PCC pavements in this area are typically reinforced due to the underlying active clays. Properly designed control joints and otherjoints systems are required to control cracking and allow pavement movement. Preliminary Recommendations for Structures The property is currently planned for residential construction. Our field and laboratory data indicate the soil and bedrock conditions vary across the site. The following discussions are preliminary and are not intended for design or construction. After grading is completed, a detailed soils and foundation investigation should be performed. Foundations and Floor Systems Our geologic and preliminary geotechnical investigation for this site indicates structures will likely require deep foundations with crawlspaces. Deep foundations are likely due to the soft, undocumented fill as well as the depth to groundwater. Below-Grade Construction Groundwater was encountered during this investigation and will limit below-grade-areas. A separation of 3 feet, preferably 5 feet, is recommended between groundwater and the bottom of footings. Below grade structures may be limited due to required separation. Surface water can infiltrate and develop adjacent to foundations walls. To reduce the risk of hydrostatic pressure developing on foundation walls,foundation drains will be necessary around all below-grade areas. We suggest foundation drains be tied to the sewer underdrain system. They may also discharge to sumps where water can be removed by pumping. In our opinion, underdrain systems offer more comprehensive control of water from the foundation drain and the impact of swelling soils on foundations, slabs, and pavements. Foundation walls and grade beams should be designed to withstand lateral earth pressures. The design pressure should be established during design-level soils investigations. 10 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Surface Drainage The performance of foundations will be influenced by surface drainage. The ground surface around proposed residences should be shaped to provide runoff of surface water away from the structure and off of pavements. We generally recommend slopes of at least 12 inches in the first 10 feet where practical in the landscaping areas surrounding residences. There are practical limitations on achieving these slopes. Irrigation should be minimized to control wetting. Roof downspouts should discharge beyond the limits of backfill. Water should not be allowed to pond on or adjacent to pavements. Proper control of surface runoff is also important to limit the erosion of surface soils. Sheet flow should not be directed over unprotected slopes. Water should not be allowed to pond at the crest of slopes. Permanent slopes should be re-vegetated to reduce erosion. Water can follow poorly compacted fill behind curb and gutter and in utility trenches. This water can soften fill and undermine the performance of the roadways, flatwork, and foundations. We recommend compactive effort be used in placement of all fill. General Design Considerations Exterior sidewalks and pavements supported above the onsite clays are subject to post construction movement. Flat grades should be avoided to prevent possible ponding, particularly next to the building due to soil movement. Positive grades away from the structures should be used for sidewalks and flatwork around the perimeter of the buildings in order to reduce the possibility of lifting of flatwork, resulting in ponding next to the structures. Where movement of the flatwork is objectionable, procedures recommended for slab-on-grade floors should be considered. Joints next to buildings should be thoroughly sealed to prevent the infiltration of surface water. Where concrete pavement is used,joints should also be sealed to reduce the infiltration of water. Since some post construction movement of pavement and flatwork may occur,joints around the buildings should be periodically observed and resealed where necessary. Roof drains should be discharged well away from the structures, preferably by closed pipe systems. Where roof drains are allowed to discharge on concrete flatwork or pavement areas next to the structures, care should be taken to ensure the area is as water-tight as practical to eliminate the infiltration of this water next to the buildings. 11 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Water Soluble Sulfates Concrete that comes into contact with soils can be subject to sulfate attack. We measured water-soluble sulfate concentrations in three samples from this site. Concentrations were measured between less than .01 and .03 percent. As indicated in our tests and ACI 332-20, the sulfate exposure class is Not Applicable or RSO. SULFATE EXPOSURE CLASSES PER ACI 332-20 Water-Soluble Sulfate(SO4) Exposure Classes in Soil A Not Applicable RSO <0.10 Moderate RS1 0.10 to 0.20 Severe RS2 0.20 to 2.00 �_Very Severe RS3 >2.00 A) Percent sulfate by mass in soil determined by ASTM C1580 For this level of sulfate concentration, ACI 332-20 Code Requirements for Residential Concrete indicates there are no cement type requirements for sulfate resistance as indicated in the table below. CONCRETE DESIGN REQUIREMENTS FOR SULFATE EXPOSURE PER ACI 332-20 Cementitious Material Ty es e Maximum Minimum Calcium Exposure Water/ Compressive ASTM ASTM ASTM Chloride Class Cement Strength A C150/ C595/ C1157/ Ratio (psi) C150M C595M C1157M Admixtures No Type No Type No No RSO N/A 2500 Restrictions Restrictions Type Restrictions Restrictions RS1 0.50 2500 II Type with (MS) MS No Designation Restrictions RS2 0.45 3000 V C Type with (HS) HS Not Designation Permitted Type with (HS) HS + RS3 0.45 3000 V+ Pozzolan or Designation plus Pozzolan or Not Slag Cement° Pozzolan or Slag Slag Cement Permitted Cement E E A) Concrete compressive strength specified shall be based on 28-day tests per ASTM C39/C39M B) Alternate combinations of cementitious materials of those listed in ACI 332-20 Table 5.4.2 shall be permitted when tested for sulfate resistance meeting the criteria in section 5.5. C) Other available types of cement such as Type III or Type I are permitted in Exposure Classes RS1 or RS2 if the C3A contents are less than 8 or 5 percent, respectively. D) The amount of the specific source of pozzolan or slag to be used shall not be less than the amount that has been determined by service record to improve sulfate resistance when used in concrete containing Type V cement.Alternatively,the amount of the specific source of the pozzolan or slab to be used shall not be less than the amount tested in accordance with ASTM C1012/C1012M and meeting the criteria in section 5.5.1 of ACI 332-20. E) Water-soluble chloride ion content that is contributed from the ingredients including water aggregates, cementitious materials, and admixtures shall be determined on the concrete mixture ASTM C1218/C1218M between 29 and 42 days. 12 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 Superficial damage may occur to the exposed surfaces of highly permeable concrete,even though sulfate levels are relatively low. To control this risk and to resist freeze-thaw deterioration, the water-to-cementitious materials ratio should not exceed 0.50 for concrete in contact with soils that are likely to stay moist due to surface drainage or high-water tables. Concrete should have a total air content of 6 percent± 1.5 percent. We advocate damp-proofing of all foundation walls and grade beams in contact with the subsoils (including the inside and outside faces of garage and crawl space grade beams). Recommended Future Investigations Based on the results of this investigation and the proposed development, we recommend the following investigations be performed: 1. Review of final site grading plans by our firm; 2. Construction testing and observation for site development; 3. Subgrade investigation and pavement design after site grading is complete; 4. Design-level soils and foundation investigations after grading; and 5. Construction testing and observation for residential building construction and paving. Limitations Our exploratory borings were located to obtain preliminary subsoil data indicative of conditions on this site. Although our borings were spaced to obtain a reasonably accurate picture of subsurface conditions, variations in the subsoils not indicated in our borings are always possible. We believe this investigation was conducted in a manner consistent with that level of skill and care ordinarily used by members of the profession currently practicing under similar conditions in the locality of this project. No warranty, express or implied, is made. This report was prepared from data developed during our field exploration, laboratory testing, engineering analysis and experience with similar conditions. The recommendations contained in this report were based upon our understanding of the planned construction. If plans change or differ from the assumptions presented herein, we should be contacted to review our recommendations. 13 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 If we can be of further service in discussing the contents of this report or in the analysis of the building and pavement from the geotechnical point of view, please call. Very truly yours, D0 LI CTLITHOMPSON, INC. 04 -EA CF�� Sep 26 2023 4:27 PM John Byers R.B. "Chip" Leadbetter, III, P.E. Staff Geologist Senior Engineer jbyers@ctithompson.com 14 ANDERSON CONSULTING ENGINEERS, INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO.FC08493.002-115 REV.2 Ir DRAKE RD. LEGEND: F/////" BH-1 INDICATES APPROXIMATE SITE • LOCATION OF EXPLORATORY / BORING WILLIAM NEAL p N APPROXIMATE PKWY. O SCALE: 1"=400' MW-1 INDICATES APPROXIMATE w 0' 200' 400' • LOCATION OF EXPLORATORY ^' BORING WITH INSTALLED HORSETOOTH RD. MONITORING WELL VICINITY MAP (FORT COLLINS,COLORADO) NOT TO SCALE EXISTING UNDERDRAIN � �ts.7ra•pr y wow vri^� �Q- ctrais i �t+w+ �'�MW-26 r. 5 BH-5 � . - f • /MW-22 Y BH-4 BH-3 MW-25 • y �,� • BH-1 - _ • - "wool M W-24 - 4 M W-23 . � BH-2 ••� Locations of ANDERSON CONSULTING ENGINEERS,INC. Exploratory Borings FIGURE STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV 2 LEGEND: BH-1 INDICATES APPROXIMATE • LOCATION OF EXPLORATORY BORING DRAKE RD. MW-1 INDICATES APPROXIMATE • LOCATION OF EXPLORATORY BORING WITH INSTALLED MONITORING WELL SITE (10.6) INDICATES MEASURED DEPTH TO WILLIAEAL o N APPROXIMATE GROUNDWATER PKWY. � v SCALE: 1"=400' W 0' 200' 400' INDICATES ESTIMATED GROUND a 4848 WATER SURFACE ELEVATION CONTOUR HORSETOOTH RD. VICINITY MAP (FORT COLLINS,COLORADO) NOT TO SCALE _ - EXISTING UNDERDRAIN Al OWW-26 A \ (7)� ` o BH-5 •V MW-22_ _., (4.5) BH-4 • t 4872 BH-3 MW-25 (4) (3.5) BH-1 (5) (7) • i�.. (4.5)—4870 MW-24 MW-23� Ty 0'. � . r ' —BH-2 O r j Q 4 K i7•- t Groundwater Elevation Contours ANDERSON CONSULTING ENGINEERS,INC. FIGURE 2 STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV 2 BH-1 BH-2 BH-3 BH-4 BH-5 El. 4874.2 El. 4879.5 El. 4877.5 El. 4873.4 El. 4873.8 LEGEND: 4,885 4,88 FILL,CLAY,SANDY,SLIGHTLY MOIST TO MOIST, MEDIUM STIFF TO STIFF, BROWN,GREY (CL) - F1 CLAY,SANDY,GRAVELLY, MOIST TO WET, MEDIUM STIFF TO STIFF, BROWN(CL) 4,880 4,88 SAND,CLAYEY,GRAVELLY, MOIST TO WET,VERY LOOSE TO MEDIUM DENSE, BROWN(SC) - 5/12 - El SAND, GRAVELLY, MOIST TO WET, MEDIUM DENSE,GREY,BROWN(SP) WC=14.4 4,875 4,87 LL=47 PI=23 _ -200=87 INTERBEDDED CLAYSTONE AND SANDSTONE, MOIST, MEDIUM HARD, BROWN, RUST, 14/ iqui 8.1 GREY DD=1 - =100 -200=58 ss=<0.01 WEATHERED CLAYSTONE, MOIST, MEDIUM HARD, GREY WC 4,870 1 6/12 = 4,87 19.5 we=ls.a DD=110 1 1 4/12 DD=0.4 sw=2,6 WC=1 DD=09 CLAYSTONE, MOIST, HARD TO VERY HARD,GREY SW=0.4 WC=16.0 DD=109 SS=0.030 9/12 DD=112 SW=0.1 OOP SW=0.9 DRIVE SAMPLE.THE SYMBOL 6/12 INDICATES 6 BLOWS OF A 140-POUND HAMMER 4,865 10/12 7/12 4 86 FALLING 30 INCHES WERE REQUIRED TO DRIVE A 2.5-INCH O.D.SAMPLER 12 INCHES. w 24/12 5/12 w w w z 0/12 z WATER LEVEL MEASURED AT TIME OF DRILLING. O O j 1 WATER LEVEL MEASURED SEVERAL DAYS AFTER DRILLING. w w J J w 4,860 20/12 50/10 50/10 4,86 w 50/6 WC=16.6 DD=114 50/8 LL=40 PI=21 WC=19.7 -200=85 DD=118 SW=0.7 4,855 50/5 50/4 4,85 50/7 50/6 NOTES: 50/4 1. THE BORINGS WERE DRILLED ON SEPTEMBER 29TH,2022 USING 4-INCH DIAMETER CONTINUOUS-FLIGHT AUGERS AND A TRUCK-MOUNTED DRILL RIG. 2. THESE LOGS ARE SUBJECT TO THE EXPLANATIONS, LIMITATIONS AND CONCLUSIONS IN 4,850 50/5 4,85 THIS REPORT. 50/9 3. WC _ INDICATES MOISTURE CONTENT(%). DD _ INDICATES DRY DENSITY(PCF). SW _ INDICATES SWELL WHEN WETTED UNDER OVERBURDEN PRESSURE(%). -200_ INDICATES PASSING NO.200 SIEVE(%). 4,845 4,84 LL INDICATES LIQUID LIMIT. PI INDICATES PLASTICITY INDEX. UC _ INDICATES UNCONFINED COMPRESSIVE STRENGTH(PSF). SS _ INDICATES SOLUBLE SULFATE CONTENT(%). 4,840 4,840 Summary Logs of Exploratory Borings ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE 3 MW-22 MW-23 MW-24 MW-25 MW-26 El. 4872.7 El. 4876.4 El. 4880.3 El. 4874.2 El. 4873.4 4,885 4,885 4,880 4,88 8/12 4,875 4,87 Ful— FICA 7/12 WC=18.8 DD=107 13/12 SW=0.4 1 WC=13.4 4,870 DD=120 12/12 4,87 F SW= F w 1 ss=o.0.o3o DD=1028 15/12 LU LU SW=0.6 WC=13.5 LL 18/12 DD=119 Z Sz SW=0.2 z 9/12 �1 SZ w 5/12 uJ W 4,865 10/12 4,86 LU 0/12 7/12 14/12 11/12 4,860 = 42/12 4,860 50/10 50/12 50/9 4,855 4,85 50/6 150/4 4,850 40/12 4,85 150/5 4,845 4,845 Summary Logs of Exploratory Borings ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV2 FIGURE 4 GROUND SURFACE PROPOSED STREET BASEMENT EXCAVATION (MINIMUM T ABOVE GROUNDWATER LEVEL) Trench FOUNDATION Backfill SEWER DRAIN TRENCH SERVICE VERIFY ELEVATION OF UNDERDRAIN SANITARY WILL PROVIDE ADEQUATE DROP SEWER FOUNDATION DRAIN TO UNDERDRAIN, MAIN PARTICULARLY WHERE DEEPER EXISTING EXCAVATIONS OCCUR(WHERE UNDERDRAIN STRUCTURAL FLOORS ARE PLANNED). SERVICE UNDERDRAIN NOT TO SCALE Conceptual Underdrain ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 Service Profile CTL I T PROJECT NO. FC08493.002-115 REV 2 FIGURE 5 4-INCH MIN. DIAMETER PERFORATED PVC UNDERDRAIN PIPE (WRAPPED WITH GEOTEXTILE FABRIC). PERFORATIONS (3/8" DIAMETER) AT 5" O.C., TWO ROWS AT 60 DEGREES FROM VERTICAL. PVC PIPE AND FITTINGS CONFORMING RESIDENCE TO ASTM 3034, SDR 35. FOUNDATION DRAIN. SANITARY 4" NON-PERFORATED SEWER CORRUGATED POLYETHYLENE PIPE (ASTM F 405). r •.e. 6 ' MIRAFI 140N 46 MIN. : . 6, MIN.- -4* . '„ :.JI...• .a Via•' +• 3/4 TO 1.5-INCH WASHED ROCK, %`-'�v• •4 r .: . LESS THAN 3 PERCENT PASSING THE NO. 200 SIEVE. I SPECIFIED - TRENCH WIDTH NOTE: NOT TO SCALE Sewer ANDERSON CONSULTING ENGINEERS,INC. U nderdraln STRAUSS LAKE DEVELOPMENT PHASE 2 Detail CTL I T PROJECT NO. FC08493.002-115 REV 2 FIGURE 6 MIN. 12" TO 18" SANITARY (BACKHOE BUCKET WIDTH) SEWER SANITARY GRAVEL SEWER ENVELOPE BEDDING d ' .=i O O O O _ _ _ _ _ _ _ -_-I 1 1-1 1 I T 1-I 1 1-1 1 I-III-III-III-I -I I I-I 11=1 11-1 11= I I-I I -I 1-I I I-III-III III-III-III-I 1-1 -III-III-III-III-III-I 1= 1=1 11-1 I III-III-I -III-III-II I 11=1 11=1 11=1 1=1 11=1 1=1 I -1 I I I I 1=1 I-11 I-1 11=111i ' -1 I I-III III-III-III-I ° � " SOLID UNDERDRAIN --111 1 I-III—III—III III-MIN. 12 Ell I - -1 1=1 1=1 =1 11—I ° . I I—III—III—I 11—III- PERFORATED UNDERDRAIN PIPE PIPE TO OUTFALL 1-1 = 11=1 LOCATION -III——1 III—I 1 1�@111111 1111-1I—II III P a�R CONCRETE NEAT-AGAINST EXCAVATION WALL AND SANITARY SEWER BEDDING NOTE: THE CONCRETE CUTOFF WALL SHOULD EXTEND INTO THE UNDISTURBED SOILS OUTSIDE THE UNDERDRAIN AND SANITARY SEWER TRENCH A MINIMUM DISTANCE OF 12 INCHES. Underdrain Cutoff Wall Detail ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO. FC08493.002-115 REV 2 FIGURE 7 APPENDIX A LABORATORY TEST RESULTS TABLE A-I: SUMMARY OF LABORATORY TEST RESULTS I } EXPANSION UNDER CONSTANT � PRESSURE. DUE TO WETTING ! I 5 l I I l 1 I l i 1 I 1 I I I I I I I I I I I I 4 -I-- I I I I I I I I I I g =-- —r- I � ! I I I I I I i I i fi 1 I l ! I 1 1 I 1 I I I I I I I I I I I 2 I I I I I I I I I I I l I I 1 1 I I ! } } 1 I I I i i i I I i i I i i I ! L I I I a d I I ! I ! I ! I I I I ! ! .._:-._.._..._.._..._..._.._. ._.._......_... _..J.-..1..._i._.._. ..._.._:-:_.:_..._...1..._..._:._: .._..._.I._..._... .._.. .._1_...L...1.....----_--:_.:_:.-..:_. ..._.._._.1.._..._...1..._... _.._..1._...L...J.._. I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i i 11 1 i I I i l 1 } 1 l 1 1 I j I �I I 1 III 1 I i I I i I 1 I I i f i i Z Z a X -5 I a I I I I I ! !.-.._+ W _.i_. l ! o I 1 1 I ! l I I I I I I 1 I I I I I I Z l l I 1 1 O -s —:._.:_:.. _.._.4-..Fn - I W I I i I I I j I I i I O $ l I l l 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 110 PCF From BH-1 AT 4 FEET MOISTURE CONTENT= 16.8 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 Test Results CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE A-1 I } I I I I I I ! I I I I 1 1 I I EXPANSION UNDER CONSTANT � PRESSURE. DUE TO WETTING I I I 5 1 1 I L I�I l 1 I 1 I I I I I I I I I I I 1 I I 1 1 I 1 1 1 I i I 4 _..I..._.!._I_....._!_.!..--_.- I 1 I 1 1 I 1 l I 1 I I I I I I I I I I I 1 I 1 1 1 l I r 1 I l I I 1 1 I 1 I I I I I I I I I I I I I I I I I I I I I l I I I I I ! 1 I I I i i i I I i i I i i I ! L I I I I d I I ! I I I I I I ! I I ! 0 _..._.._._._.._..._.._- ._.._......_:.. ._.._I._..1..._1._.._.. ..._:._:-:_.:_..._...1..._... _:-:_.:_:... ..._.._._.1.._:.._..:1..._..._.._..1._...L...J.._. I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I i � III i I I I I -3 1 ri J I I I I I I I I I l I I I I I l I 1 I Z O -4 -- 1 I ! I I ! l I 1 I Z A X -5 I -.._........ W _.i_. 1 1 ! ! 0 1 I 1 1 I i 1 I I I I I I 1 I I I I I I Z l l I 1 1 O -s —:._.:_:.. _.._.4- __.�. t._ _.: a_.__.:_ ._.._ t 1 a.. :._.: - Fn I I I W a I __._. 1 1 I 1 O $ l I l l 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 110 PCF From BH-2 AT 9 FEET MOISTURE CONTENT= 19.5 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 Test Results CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE A-2 3 i I I : -1i EXPANSION UNDER CONSTANT 2 PRESSURE DUE TO WETTING I I i l i i l i I I i I I I - - ' - �0 x W , 0 2 -- -- fifi� -- �- W 3 I 1 1 j IT a l 1 0 4 U 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of CLAYSTONE DRY UNIT WEIGHT= 118 PCF From BH-3 AT 19 FEET MOISTURE CONTENT= 19.7 % 3 Ijl EXPANSION UNDER CONSTANT z - -- i_PRESSURE DUE TO WETTING nil Z II 1 111 0 0 - -1 �—--' J -------1 , Z I I - w a i I i I I i i i I i i I II i I i i i I cn cn j j ii it a � I __ I I l l O I -4 0.1 1.0 10 100 OPPI IFn PRFSSI IRF -KRF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 112 PCF From BH-4 AT 4 FEET MOISTURE CONTENT= 16.0 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE A-3 3 i I I -1j EXPANSION UNDER CONSTANT 2 PRESSURE DUE TO WETTING I I i I I i l i i I I I I I I I i III I I I I I I I I I Z X II LLI Ocn cf) 1 1 i I i i 0 j it U -4 0.1 1.0 10 100 APPLIED PRESSURE -KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 109 PCF From BH-5 AT 4 FEET MOISTURE CONTENT= 21.2 % 3 Ijl EXPANSION UNDER CONSTANT z - -- i_PRESSURE DUE TO WETTING nili I i iI � I I II I j I i I I I 'I Z II III 0 0 j ..... Z 11 j Q a w 1 - ----i---- --�- - -- -- - - a- - a i I i I I i i I i i I II i I i i i I Lu cn I -4 0.1 1.0 10 100 OPPI IFn PRFSSI IRF -KRF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 107 PCF From MW-23 AT 4 FEET MOISTURE CONTENT= 18.8 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE A-4 3 I I Ii 1 I I I I I I I I I I 2 � NO MOVEMENT DUE TO WETTING _ I I i I l i i I I '/� . I I l 1 71, t it X II LLI fi 1-171cf) 0 CO I I I i i t 3 A IT a l 1 l t O 4 U 0.1 to 10 100 APPLIED PRESSURE -KSF Sample of CLAY, SANDY(CL) DRY UNIT WEIGHT= 120 PCF From MW-24 AT 9 FEET MOISTURE CONTENT= 13.4 % 3 I ' ll EXPANSION UNDER CONSTANT 2 - -1— -L-PRESSURE DUE TO WETTING - ..._.... --..._... II III Z - - -0 .....L -" _ ...- I -- z Q i I I III I I I I I I i I I I I I I X - ---- 1 --�- i--- -- - -- - 1 - a- - W _ I ! a I II i ' II I i Iii I II'i i I i i iI o -2Lu - cn ii a O I -4 0.1 1.0 10 100 OPPI IFn PRFSSI IRF -KRF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 102 PCF From MW-25 AT 4 FEET MOISTURE CONTENT= 17.8 % ANDERSON CONSULTING ENGINEERS,INC. Swell Consolidation STRAUSS LAKE DEVELOPMENT PHASE 2 CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE A-5 I } I I I I I I I I I I I I I I } � L I EXPANSION UNDER CONSTANT I I I PRESSURE DUE TO WETTING 5 l I I l 1 I l i 1 I 1 I I I I I I I I I I I I 4 I I I I I I I I I I I _ I I I I I I I I I I 2 _.._. ._ y t.._t_ _ 1-- — t — t .+-1 __ I I I I I I I I I I I l I I 1 L 1 I I I 1 I I I I I I I I I I I I i i i I I i i I i i ! I ! I I I I I I I ! 0 ._..._..._..._..._..._..I_..._..._..._. ._.._...... _...L.... _..._....1...._... _.._..1._...L...J.._. I I I I I I I I I I I I I I I I I I I I I ! I I ! I I I I I I I I I I I I ! ! I I ! I I I I ! 2 1 } 1 ! l 1 I I I i I 1 I I i f i i Z Z A a II ! X -5 -.._. —.._.a..._..._. __+ .�_�_ .._. — a_._ _._ 4 _ i a.. _.. �.—.._... W I. l I I I 1 I I I I I I Z l l I 1 1 O -s —:._.:_:.. _.._.4-.. - � W I I I I ! O $ l I l l 0.1 1.0 10 100 APPLIED PRESSURE - KSF Sample of FILL, CLAY, SANDY(CL) DRY UNIT WEIGHT= 119 PCF From MW-26 AT 4 FEET MOISTURE CONTENT= 13.5 % Swell Consolidation ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 Test Results CTL I T PROJECT NO.FC08493.002-115 REV 2 FIGURE A-6 TABLE A-1 SUMMARY OF LABORATORY TESTING ATTERBERG LIMITS SWELL TEST RESULTS* PASSING WATER- MOISTURE DRY LIQUID PLASTICITY APPLIED NO. 200 SOLUBLE DEPTH CONTENT DENSITY LIMIT INDEX SWELL' PRESSURE SIEVE SULFATES BORING (FEET) N (PCF) (%) (PSF) N N DESCRIPTION BH-1 4 16.8 110 0.4 500 0.03 FILL, CLAY, SANDY (CL) BH-2 4 14.4 47 23 87 FILL, CLAY, SANDY (CL) BH-2 9 19.5 110 2.6 1,100 CLAY, SANDY(CL) BH-3 4 18.1 100 58 <0.01 CLAY, SANDY(CL) BH-3 19 19.7 118 0.7 2,400 CLAYSTONE BH-4 4 16.0 112 0.9 500 FILL, CLAY, SANDY (CL) BH-5 4 21.2 109 0.1 500 FILL, CLAY, SANDY (CL) BH-5 14 16.8 114 40 21 85 CLAYSTONE MW-23 4 18.8 107 0.4 500 FILL, CLAY, SANDY (CL) MW-24 9 13.4 120 0.0 1,100 0.03 CLAY, SANDY(CL) MW-25 4 17.8 102 0.6 500 FILL, CLAY, SANDY (CL) MW-26 1 4 13.5 1 119 0.2 500 FILL, CLAY, SANDY (CL) NEGATIVE VALUE INDICATES COMPRESSION. ANDERSON CONSULTING ENGINEERS,INC. STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO.FC08493.002-115 REV 2 Page 1 of 1 APPENDIX B GUIDELINE SITE GRADING SPECIFICATIONS GUIDELINE SITE GRADING SPECIFICATIONS 1. DESCRIPTION This item shall consist of the excavation, transportation, placement and compaction of materials from locations indicated on the plans, or staked by the Engineer, as necessary to achieve preliminary street and overlot elevations. These specifications shall also apply to compaction of excess cut materials that may be placed outside of the development boundaries. 2. GENERAL The Soils Engineer shall be the Owner's representative. The Soils Engineer shall approve fill materials, method of placement, moisture contents and percent compaction, and shall give written approval of the completed fill. 3. CLEARING JOB SITE The Contractor shall remove all vegetation and debris before excavation or fill placement is begun. The Contractor shall dispose of the cleared material to provide the Owner with a clean, neat appearing job site. Cleared material shall not be placed in areas to receive fill or where the material will support structures of any kind. 4. SCARIFYING AREA TO BE FILLED All topsoil and vegetable matter shall be removed from the ground surface upon which fill is to be placed. The surface shall then be plowed or scarified until the surface is free from ruts, hummocks or other uneven features, which would prevent uniform compaction. 5. COMPACTING AREA TO BE FILLED After the foundation for the fill has been cleared and scarified, it shall be disked or bladed until it is free from large clods, brought to the proper moisture content(0 to 3 percent above optimum moisture content for clays and within 2 percent of optimum moisture content for sands) and compacted to not less than 95 percent of maximum dry density as determined in accordance with ASTM D698. 6. FILL MATERIALS Fill soils shall be free from organics, debris, or other deleterious substances, and shall not contain rocks or lumps having a diameter greater than six (6) inches. Fill materials shall be obtained from cut areas shown on the plans or staked in the field by the Engineer. ANDERSON CONSULTING ENGINEERS, INC. Appendix B-1 STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 On-site materials classifying as CL, CH, SC, SM, SW, SP, GP, GC, and GM are acceptable. Concrete, asphalt, organic matter and other deleterious materials or debris shall not be used as fill. 7. MOISTURE CONTENT AND DENSITY Fill material shall be moisture conditioned and compacted to the criteria in the table, below. Maximum density and optimum moisture content shall be determined from the appropriate Proctor compaction tests. Sufficient laboratory compaction tests shall be made to determine the optimum moisture content for the various soils encountered in borrow areas. FILL COMPACTION AND MOISTURE REQUIREMENTS Soil Depth from Moisture Requirement Overlot Grade Density Requirement Type (feet) (% from optimum) Clay 0 to 20 feet +1 to +4 95% of ASTM D 698 Sand -2 to +2 95% of ASTM D 698 Clay Greater than 20 -2 to +1 98% of ASTM D 698 F§—and feet -2 to +1 95% of ASTM D 1557 The Contractor may be required to add moisture to the excavation materials in the borrow area if, in the opinion of the Soils Engineer, it is not possible to obtain uniform moisture content by adding water on the fill surface. The Contractor may be required to rake or disc the fill soils to provide uniform moisture content through the soils. The application of water to embankment materials shall be made with any type of watering equipment approved by the Soils Engineer, which will give the desired results. Water jets from the spreader shall not be directed at the embankment with such force that fill materials are washed out. Should too much water be added to any part of the fill, such that the material is too wet to permit the desired compaction from being obtained, rolling and all work on that section of the fill shall be delayed until the material has been allowed to dry to the required moisture content. The Contractor will be permitted to rework wet material in an approved manner to hasten its drying. ANDERSON CONSULTING ENGINEERS, INC. Appendix B-2 STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 8. COMPACTION OF FILL AREAS Selected fill material shall be placed and mixed in evenly spread layers. After each fill layer has been placed, it shall be uniformly compacted to not less than the specified percentage of maximum density. Fill shall be compacted to the criteria above. At the option of the Soils Engineer, soils classifying as SW, GP, GC, or GM may be compacted to 95 percent of maximum density as determined in accordance with ASTM D 1557 or 70 percent relative density for cohesionless sand soils. Fill materials shall be placed such that the thickness of loose materials does not exceed 12 inches and the compacted lift thickness does not exceed 6 inches. Compaction as specified above, shall be obtained by the use of sheepsfoot rollers, multiple-wheel pneumatic-tired rollers, or other equipment approved by the Engineer for soils classifying as CL, CH, or SC. Granular fill shall be compacted using vibratory equipment or other equipment approved by the Soils Engineer. Compaction shall be accomplished while the fill material is at the specified moisture content. Compaction of each layer shall be continuous over the entire area. Compaction equipment shall make sufficient trips to ensure that the required density is obtained. 9. COMPACTION OF SLOPES Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable equipment. Compaction operations shall be continued until slopes are stable, but not too dense for planting, and there is not appreciable amount of loose soils on the slopes. Compaction of slopes may be done progressively in increments of three to five feet(3'to 5') in height or after the fill is brought to its total height. Permanent fill slopes shall not exceed 3:1 (horizontal to vertical). 10. PLACEMENT OF FILL ON NATURAL SLOPES Where natural slopes are steeper than 20 percent in grade and the placement of fill is required, benches shall be cut at the rate of one bench for each 5 feet in height (minimum of two benches). Benches shall be at least 10 feet in width. Larger bench widths may be required by the Engineer. Fill shall be placed on completed benches as outlined within this specification. 11. DENSITY TESTS Field density tests shall be made by the Soils Engineer at locations and depths of his choosing. Where sheepsfoot rollers are used, the soil may be disturbed to a depth of several inches. Density tests shall be taken in compacted material below the disturbed surface. When density tests indicate that the density or moisture content of any layer of fill or portion thereof is not within specification, the particular layer or portion shall be reworked until the required density or moisture content has been achieved. ANDERSON CONSULTING ENGINEERS, INC. Appendix B-3 STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 77=- 12. SEASONAL LIMITS No fill material shall be placed, spread or rolled while it is frozen, thawing, or during unfavorable weather conditions. When work is interrupted by heavy precipitation, fill operations shall not be resumed until the Soils Engineer indicates that the moisture content and density of previously placed materials are as specified. 13. NOTICE REGARDING START OF GRADING The Contractor shall submit notification to the Soils Engineer and Owner advising them of the start of grading operations at least three (3) days in advance of the starting date. Notification shall also be submitted at least 3 days in advance of any resumption dates when grading operations have been stopped for any reason other than adverse weather conditions. 14. REPORTING OF FIELD DENSITY TESTS Density tests made by the Soils Engineer, as specified under"Density Tests" above, shall be submitted progressively to the Owner. Dry density, moisture content, and percentage compaction shall be reported for each test taken. 15. DECLARATION REGARDING COMPLETED FILL The Soils Engineer shall provide a written declaration stating that the site was filled with acceptable materials and was placed in general accordance with the specifications. ANDERSON CONSULTING ENGINEERS, INC. Appendix B-4 STRAUSS LAKE DEVELOPMENT PHASE 2 CTLIT PROJECT NO. FC08493.002-115 REV.2 APPENDIX A.3. GROUNDWATER WELL LOCATIONS POP T Ic =_ STAFF GAGE LOCATION UPSTREAM SIDE CMP 4 m IN POND CULVERT CROSSING N - 1442312.34 E- 3133614.46 E= 31343561 _ #v GRAPHICAL SCALE IN Fr- o� �•` ELEV. OF 4.0' MARK ON TOP OF CMP ELEV. = 4872.84 G c C O c 3 STAFF GAGE= 4874.49 0 100 200 400 N - 1442159.94 DOWNSTREAM SIDE CMP A4 �� o E = 3134346.36 CULVERT CROSSING s- TOP OF WELL ELEV. - 4878.38 N = 1442259.88 - +� GROUND ELEV. - 4875.84 E = 3134340.79 NORTHEAST WINGWALL OF TOP OF CMP ELEV. = 4873.27 WIWAM NEAL PARKWAY N - 1442014.41 E - 3133430.81 UPSTREAM SIDE CMP CULVERT CROSSING TOP OF WALL ELEV. - 4885.90 N = 1441958.75 �y J f 4 lej r E= 3134542.94 ri'A i TOP OF CMP ELEV. = 4871.61 WILLIAM NEAL PKWY DOWNSTREAM SIDE CMP CULVERT CROSSING N = 1441890.94 MW#1: E= 3134562.54 - NORTHEAST WINGWALL OF N - 1442083.69 TOP OF CMP ELEV. = 4871.77 J _ WIW E -AM NEAL PARKWAY 3133583.71 JTOP OF WELL ELEV. - 4888.17 +. �t* N = 1441929.86 GROUND ELEV. - 4806.04 N =1 w Z e _ E= 3133429.58 �N - 1441760.99 L. Q TOP OF WALL ELEV. = 4885.79 E = 3134585.95 ... , TOP OF WELL ELEV. = 4873.87 GROUND ELEV. = 4873.20 W Z Z O MW#5, (n . . I MW#4- N - 1441126.47 - c N = 1441173.12 E - 3134185.12 Q O Q E= 3133572.88 TOP OF WELL ELEV. - 4884.20 MW#6: = O P TOP OF WELL ELEV. = 4886.54 GROUND ELEV. - 4881.49 N = 1*441184.27 GROUND ELEV. = 4885.21 E= 3134780.94 Q. Q w •' ` r 0 TOP OF WELL ELEV. = 4876.22 Z V J GROUND ELEV. = 4873.76 0 O w '•� ` LL J . 1 iyo. �o f�a0 o. r W� J ��ti MW#9: LJ.I N = 1440514.11 N =i 440519.71 N - 1440505.61 w � o E = 3133593.70 Y E- 3135242.04 Z E= 3134444.65(v TOP OF WELL ELEV. = 4887.82 TOP OF WELL ELEV. = 4882.82 TOP OF WELL ELEV. - 4875.44 Q W GROUND ELEV. = 4883.74 GROUND ELEV. = 4880.49 GROUND ELEV. - 4873.40 J C PERCHERON ROAD c cl) O F y- w «_ C/) o MW#13: MW#12: MW#11: MW#10: N = 1440144.78 14 z N = 1439864.43 N = 1439954.89 N = 39916.07 E - 3133482.98 E= 3134098.38 E= 3134845.95 E= 3135619.20 '�- TOP OF WELL ELEV. = 4884.76 TOP OF WELL ELEV. = 4882.91 TOP OF WELL ELEV. = 4879.81 TOP OF WELL ELEV. = 4873.73 _ GROUND_ELEV. - 4862.22 GROUND ELEV. = 4880.66 GROUND ELEV. = 4877.64 GROUND ELEV. = 4870.56 0 a i UPSTREAM NORTHWEST WINGWALL OF DROP/CHECK STRUCTURE N - 1439714.30 E- 3135879.02 TOP OF WALL ELEV. - 4865.45 c� = M W#15: N = 1439401.70' MW#18: E= 3133562.21 N = 1439334.98 DOWNSTREAM SOUTHEAST WINGWALL i TOP OF WELL ELEV. = 4910.19 MW#16- E= 3135858.93 ��OF DROP/CHECK STRUCTURE yyy GROUND ELEV. = 4906.86 N = 1439355.53 TOP OF WELL ELEV. = 4870.84 N = 1439702.15 E = 3134162.32 GROUND ELEV. = 4868.84 E= 3135899.88 3 e J TOP OF WELL ELEV. = 4681.84 TOP OF WALL ELEV. = 4865.18 i GROUND ELEV. = 4880.01 MW#17: * E= 3 34621.89 CHECKRSTRUCTURE N WINGWALL OF ' .� - x"i a N = 1439MW 40 GROUND TOP OF WELL 4877.5377.66 _ E - 3136175.06 E = 3133471.84 r, TOP OF WALL ELEV. - 4864.14 TOP OF WELL ELEV. = 4918.48 c GROUND ELEV. = 4917.35 ' "Aa _ DRAWN BY: BAS Abkg AM, NOTES: DESIGNED BY: BAS f CHECKED BY: BAS +` THIS DRAWING IS BASED ON COLORADO STATE PLANE NORTH COORDINATE 1 ...................... ��ea PROJECT NUMBER: < NORTHEAST WINGWALL OF miallowSYSTEM. ALL ELEVATIONS SHOWN HERON ARE IN THE NORTH AMERICAN �M RADIAL GATE STRUCTURE HORSETOOTH ROAD COCLF10 N = 1439203.47 ,� �p VERTICAL DATUM 7988 (NAVD88) DATE: �� �• E= 3134346.67 1 n~��'-'i� !�i_- OS 28 2024 TOP of WALL ELEV. = 4e81.1 2015 AERIAL PHOTOGRAPH OBTAINED FROM NATIONAL AGRICULTURE IMAGERY SHEET: PROGRAM (NAIP) a P: COCLF10-STRAUSS LAKE DEVELOPMENT GROUNDWATER MONITORING ACAD P2- MONITORING WELL LOCATION MAP FOR REPORT.DWG DOWNSTREAM CENTER OF HEADWALL ON ENVIRONMENTAL DRIVE N = 1,1442,15,33 E = 3133359.06 TOP OF WALL ELEV. _ 4884.80 WINGWALL ON SOUTHEAST SIDE OF SIPHON OUTLET N = 1443918.94 ` E = 3133422.58 MW#24: ' TOP OF WALL ELEV. = 4877.65 N = 1443801.26 E = 3133675.08 TOP OF WELL ELEV. = 4883.45 +� GROUND ELEV. = 4880.29 N = 14124 BH#3: s E = 343576 13355533 N = 1443641.91 TOP OF WELL ELEV. = 4880.99 E = 3133951.63 GROUND ELEV. = 4879.55 TOP OF WELL ELEV. = 4880.23 GROUND ELEV. = 4877.48 \\� +p ♦a,,, '�'"V. MW 25: BHy5: # N = 1443341.17 N = 1443308.39 E = 3134245.24 '07_ t,, E = 3133975.00 TOP OF WELL ELEV. = 4874.05 I `` �. 'j; TOP OF WELL ELEV. = 4875.66 GROUND ELEV. = 4873.81 1�'F"1 GROUND ELEV. = 4874.19 • H+�yr�. �•-�11�'Fi MW#23: - N = 1443136.26 *►- :P r ' \`1� N = 1443249.46 E = 3134079.65 E = 3133704.69 TOP OF WELL ELEV. = 4874.76 TOP OF WELL ELEV. = 4877.90 GROUND ELEV. = 4873.38 '+A ' GROUND ELEV. = 4876.41 {. SH#1: N = 1443152.66 - N - 1442969.94 E = 3134550.82 E = 3133913.63 TOP OF WELL ELEV. = 4876.66 TOP OF WELL ELEV. = 4875.39 MW#22 GROUND ELEV. = 4873.42 GROUND ELEV. = 4874.17 E = 3134165.69 1442709.7 ' \ > TOP OF WELL ELEV. = 4873.81 GROUND ELEV. = 4872.70 PHASE 2 INSTALLATION (TYP.) 1�ems^ Cn PHASE 2 STAFF GAGE LOCATION # INSTALLATION F,qT� IN POND PHASE 1 INSTALLAA TION (TYP.; ELEV. OF 4.0' MARK ON FS�� STAFF GAGE = 4876.29 nA, �'--' "-41� � h _ UPSTREAM SIDE CMP ,1",✓/� r - MW#1: '. CULVERT CROSSING q� - -�� N = 1442083.69-�- N = 14-41958.75 /w- E = 3133583.71 E = 3134542.94 �ll/� •' TOP OF WELL ELEV. = 4-888.17 TOP OF CMP ELEV. = 4871.61 ��' GROUND ELEV. = 4886.04 ' � '4 / DOWNSTREAM SIDE CMP .�. 'k...aaa/// CULVERT CROSSING WILLIAM NEAL PKWY MW#20. N = 1441890.94 N = 1442111.79 E = 3134562.54 / E = 3134296.84 TOP OF CMP ELEV. = 4871.77 NORTHEAST WINGWALL OF / TOP OF WELL ELEV. = 4878.32 .f WILLIAM NEAL PARKWAY / GROUND ELEV. = 4877.34 r - N = 1442014.41 r E = 3133430.81 tT.Or P OF WALL ELEV. = 4885.9' r MW#5: N = 1441126.47 "SOUTHEAST WINGWALL OF '�I E = 3134185.12 tA. -til ti WILLIAM NEAL PARKWAY MW#21; TOP OF WELL ELEV. = 4884.28 N = 1441929.E N = 1441685.02 GROUND ELEV. = 4881.49 E = 3133429, E = 3134036.65 1. TOP OF !w'l'I n r+J IFfi'" TOP OF WELL ELEV. = 4883.34 M W#1 fy GROUND ELEV. = 4882.27 N = 1441276.97 E = 3134751.31 TOP OF WELL ELEV. = 4877.43 01 GROUND ELEV. = 4876.34 M W#4: N = 1441173.12 _ E = 3133572.88 p �O TOP OF WELL ELEV. = 4886.54 Q . GROUND ELEV. = 4885.2'. 0 IV4, p O� RIGDEN RESERVOIR MW/#8: 0 -MW�!9: ' J LL N = 1440519.71 N = 1440505.61 E = 3134444.65 E= 3135242.04 PERCHERON ROAD w TOP WELL ELEV. 4882.82 ELEV.LL E= 1873,40754 GROUND ELEV. = 488 GROUND 0.49 e MW#7. N = 1440514.11 E = 3133593.70 TOP OF WELL ELEV. = 4887.82 - _ GROUND ELEV. = 4883.74' MW#12: MW#11: \'� MW#1O: N = 1439864.43 N = 1439954.89 N = 1439916,07 E = 3134098.38 E = 3134845.95 E = 3135619.20 TOP OF WELL ELEV. = 4882.91 TOP OF WELL ELEV. = 4879.81 TOP OF WELL ELEV. = 4873.73 MW#13: � GROUND ELEV. = 4880.66 GROUND ELEV. = 4877.64 �f GROUND ELEV. = 4870.56 N = 1440144.78 =-- -- - -- - E = 3133482.98 ' TOP OF WELL ELEV. 4884.7 GROUND El UPSTREAM NORTHWEST WINGWALL OF DROP/CHECK STRUCTURE N = 1439714.30 s MW#15: E= 3135879.02 N = 1439401.70 MW#18: TOP OF WALL ELEV. = 4865.45 E = 3133562.21' MW#16: N = 1439334.98 TOP OF WELL ELEV. = 4910.19r --� E = 3135858.93 GROUND ELEV. = 4906.95 N = 1439355.53 TOP OF WELL ELEV. = 4870.84 E = 3134162.32 _.e OUTHEAST WIN GROUND ELEV. = 4868.84 - DOWNSTREAM S ,- TOP WELL ELEV. 4881.84 OF DROP/CHECK STRUCTURE - GROUND ELEV. = 488 0.01 N = 1439702.15 .88 TOP OF 3WALL ELEV. 4865.18- MW#14,.•W r'.- - N = 1439223 40 E = 3133471.841, TOP OF WELL ELEV. = 4918.48Z,^ - GROUND ELEV. = 4917.35 - ,:,:WESTERN WINGWALL OF r r �+ ,,_; HORSETOOTH ROAD CHECK STRUCTURE _ _ N = 1439358.65 "` -- - E = 3136175.06 �ti' MW#17: TOP OF WALL ELEV. = 4864,14 E = 3134621.89 TOP OF WELL ELEV. = 4877.66 NORTHEAST WINGWALL OF GROUND ELEV. = 4877.53 RADIAL GATE STRUCTURE `y N = 14-39203.47 E = 3134346.67r T. F ' TOP OF WALL ELEV. = 4881.1 -- _ r t � r - NOTES L THIS DRAWING IS BASED ON COLORADO STATE PLANE NORTH COORDINATE N SYSTEM. ALL ELEVATIONS SHOWN HERON ARE IN THE NORTH AMERICAN VERTICAL DATUM 1988 (NAVD88) GRAPHICAL SCALE IN FT: 2023 AERIAL PHOTOGRAPH OBTAINED FROM NATIONAL AGRICULTURE IMAGERY PROGRAM (NAIP) 0 125 250 500 xm O EA z C) PHASE 2: n o m m 0 ` STRAUSS LAKE MONITORING WELL = m a c ' . Anderson Consulting Engineers, Inc N DEVELOPMENT LOCATIONS AND e Civil•Yi'ater Rero+rrces•ErrvironmerVal N ; 375 B:ui 14.11 ootli Ro d,Building 5.F.,Cu im,CO 80- Pdone(9 �,6.OI20,Fa(9�0,2,fi.,,1 to ELEVATIONS APPENDIX A.4. GROUNDWATER MONITORING DATA TABLE A.4.1:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 1 Monitoring Well Data 2018 DATA August 16,2018 September 17,2018 October 22,2018 November 21,2018 December 17,2018 Ground Depth from Top of Distance to Groundwater Groundwater Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Monitoring Elevation Ground to Top PVC/Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Well R at Well of PVC/Well Elevation from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground (ft,NAVD88) (inches) (ft,NAVD88) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 13.9 4874.3 11.8 14.0 4874.2 11.8 13.9 4874.3 11.8 14.3 4873.9 12.1 14.4 4873.8 12.2 2 4875.8 30.5 4878.4 8.0 4870.4 5.4 8.0 4870.4 5.4 8.3 4870.1 5.8 8.9 4869.5 6.4 8.8 4869.6 6.3 3 4873.2 8.0 4873.9 4.4 4869.5 3.7 4.4 4869.5 3.7 4.7 4869.2 4.0 5.2 4868.7 4.5 5.1 4868.7 4.5 4 4885.2 16.0 4886.5 11.7 4874.9 10.3 11.7 4874.8 10.4 10.8 4875.8 9.4 12.0 4874.5 10.7 12.0 4874.5 10.7 5 4881.5 33.5 4884.3 12.8 4871.5 10.0 12.9 4871.4 10.1 12.5 4871.8 9.7 13.3 4871.0 10.5 13.3 4871.0 10.5 6 4873.8 29.5 4876.2 8.3 4867.9 5.8 8.3 4867.9 5.8 8.6 4867.7 6.1 9.1 4867.1 6.7 9.1 4867.2 6.6 7 4883.7 49.0 4887.8 12.9 4874.9 8.8 12.9 4874.9 8.8 11.4 4876.5 7.3 13.2 4874.7 9.1 13.2 4874.7 9.1 8 4880.5 28.0 4882.8 13.1 4869.7 10.8 13.1 4869.7 10.8 12.6 4870.2 10.3 13.5 4869.3 11.2 13.5 4869.4 11.1 9 4873.4 24.5 4875.4 9.3 4866.2 7.2 9.2 4866.2 7.2 9.4 4866.1 7.3 9.9 4865.5 7.9 9.8 4865.6 7.8 10 4870.6 38.0 4873.7 9.7 4864.0 6.5 9.7 4864.0 6.5 9.8 4864.0 6.6 10.1 4863.6 7.0 10.1 4863.7 6.9 11 4877.6 26.0 4879.8 12.1 4867.7 9.9 12.2 4867.6 10.0 12.0 4867.9 9.8 12.6 4867.3 10.4 12.5 4867.3 10.3 12 4880.7 27.0 4882.9 10.4 4872.5 8.1 10.4 4872.6 8.1 9.0 4874.0 6.7 10.6 4872.3 8.4 10.6 4872.3 8.4 13 4882.2 30.5 4884.8 9.4 4875.4 6.9 9.3 4875.5 6.8 7.9 4876.9 5.3 9.6 4875.1 7.1 9.6 4875.1 7.1 14 4917.4 13.5 4918.5 18.6 4899.9 17.5 18.8 4899.7 17.6 18.7 4899.8 17.5 18.6 4899.8 17.5 18.7 4899.8 17.6 15 4906.9 40.0 4910.2 10.9 4899.3 7.6 11.1 4899.1 7.7 10.9 4899.3 7.5 10.9 4899.3 7.5 10.9 4899.3 7.6 16 4880.0 22.0 4881.8 9.7 4872.2 7.8 9.7 4872.2 7.8 8.0 4873.9 6.1 9.6 4872.2 7.8 9.7 4872.1 7.9 17 4877.5 1.5 4877.7 9.7 4868.0 9.6 9.7 4868.0 9.6 9.0 4868.7 8.9 9.7 4868.0 9.5 9.7 4868.0 9.6 18 4868.8 24.0 4870.8 9.5 4861.3 7.5 9.4 4861.4 7.4 9.4 4861.5 7.4 9.5 4861.3 7.5 9.5 4861.4 7.4 FCRID Water Surface Elevations 2018 DATA August 16,2018 September 17,2018 October 22,2018 November 21,2018 December 17,2018 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation(ft, (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Northeast Wingwall 4885.90 121 10.1 4875.8 120 10.0 4875.9 101 8.4 4877.5 127 10.5 4875.4 126 10.5 4875.4 at William Neal Parkway Southeast Wingwall 4885.79 120 10.0 4875.8 119 9.9 4875.9 99 8.2 4877.E 124 10.3 4875.5 125 10.4 4575.4 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 79 6.6 4874.5 81 6.7 4874.4 47 3.9 4877.2 82 6.9 4874.2 81 6.7 4874.4 of Horsetooth Road Boxelder Water Surface Elevations 2018 DATA August 16,2018 September 17,2018 October 22,2018 November 21,2018 December 17,2018 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Top of CMP-Upstream (Northern Crossing) 4572.84 26.5 2.2 4870.E 26.3 2.2 4870.7 33.5 2.8 4870.0 41.3 3.4 4869.4 40.0 3.3 4869.5 Top of CMP-Downstream (Northern Crossing) 4873.27 34.0 2.8 4870.4 34.5 2.9 4870.4 40.3 3.4 4869.9 46.0 3.8 4869.4 44.5 3.7 4869.E Top of CMP-Upstream 4871.61 24.0 2.0 4869.E 24.0 2.0 4869.E 30.5 2.5 4869.1 38.0 3.2 4868.4 37.0 3.1 4868.5 (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 27.0 2.3 4869.5 26.5 2.2 4869.E 33.0 2.8 4869.0 40.3 3.4 4868.4 39.0 3.3 4868.5 Northwest Corner of Wingwall 4865.45 24.5 2.0 4863.4 24.5 2.0 4863.4 28.3 2.4 4863.1 34.0 2.8 4862.E 33.8 2.8 4862.E Upstream of Drop Structure Southeast Corner of Wingwall 4865.18 36.0 3.0 4862.2 36.0 3.0 4862.2 42.0 3.5 4561.7 50.0 4.2 4861.0 48.5 4.0 4861.1 Downstream of Drop Structure Western Wall at Check Structure Adjacent to Rigden Reservoir 4864.14 34.0 2.8 4861.3 34.0 2.8 4861.3 37.0 3.1 4861.1 42.3 3.5 4860.E 42.0 3.5 4860.E Pond Water Surface Elevations 2018 DATA August 16,2018 September 17,2018 October 22,2018 November 21,2018 December 17,2018 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Staff Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage (ft,NAVD88) (ft) (ft) A NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) A NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) Staff Gage Located In Southwestern N/A N/A N/A N/A N/A N/A N/A N/A N/A Corner of Pond 4874.49 1.S 2.2 4872.3 1.3 2.7 4871.8 (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Pond Frozen) (Pond Frozen) (Pond Frozen) Page 1 of 6 TABLE A.4.1:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 1 Monitoring Well Data 2019 DATA January 15,2019 February 15,2019 March 21,2019 April 16,2019 May 16,2019 June 11,2019 Ground Depth from Top of Distance to Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Distance to Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Monitoring Elevation Ground to Top PVC/Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Well R at Well of PVC/Well Elevation from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground (ft,NAVD88) (inches) (ft,NAVD88) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 14.4 4873.8 12.3 14.5 4873.7 12.3 14.3 4873.9 12.2 13.8 4874.4 11.7 13.6 4874.5 11.5 13.4 4874.8 11.2 2 4875.8 30.5 4878.4 8.9 4869.5 6.3 8.9 4869.5 6.4 8.5 4869.9 6.0 8.0 4870.3 5.5 8.0 4870.4 5.4 7.8 4870.5 5.3 3 4873.2 8.0 4873.9 5.1 4868.8 1 4.4 5.1 4868.7 1 4.5 4.9 4869.0 4.2 N/A N/A N/A 4.4 4869.5 3.7 4.3 4869.6 3.6 4 4885.2 16.0 4886.5 12.1 4974.5 10.7 12.1 4874.4 10.8 12.0 4874.6 10.6 11.7 4874.8 10.4 11.3 4875.2 10.0 11.0 4875.5 9.7 5 4881.5 33.5 4884.3 13.3 4871.0 10.5 13.4 4870.9 10.6 13.1 4871.2 10.3 12.7 4871.6 9.9 12.5 4871.8 9.7 12.3 4872.0 9.5 6 4873.8 29.5 4876.2 9.1 4967.1 6.6 9.1 4867.1 6.7 8.8 4867.4 6.4 8.4 4867.8 5.9 8.4 4867.9 5.9 8.2 4868.0 5.7 7 4883.7 49.0 4887.8 13.2 4874.6 9.1 13.3 4874.5 9.2 13.2 4874.6 9.1 13.0 4874.8 8.9 12.4 4875.5 8.3 12.2 4875.6 8.1 S 4880.5 28.0 4882.8 13.5 4869.3 11.2 13.5 4869.3 11.2 13.3 4369.5 11.0 13.0 4869.8 10.7 12.7 4870.1 10.4 12.6 4870.3 10.2 9 4873.4 24.5 4875.4 9.9 4865.6 7.8 9.9 4865.6 7.8 9.6 4865.9 7.5 9.2 4866.3 7.1 9.1 4866.4 7.0 9.0 4866.5 6.9 10 4870.6 38.0 4873.7 10.1 4863.6 6.9 10.1 4863.6 6.9 9.8 4863.9 6.7 9.6 4864.2 6.4 9.3 4864.4 6.2 9.3 4864.5 6.1 11 4877.6 26.0 4879.8 12.6 4867.2 10.4 12.6 4867.2 10.4 12.4 4867.4 10.2 12.1 4867.7 9.9 11.9 4867.9 9.7 11.7 4868.1 9.6 12 4880.7 27.0 4882.9 10.7 4872.2 8.5 10.8 4872.1 8.5 10.7 4972.3 8.4 10.4 4872.6 8.1 9.8 4873.1 7.5 9.5 4873.4 7.3 13 4882.2 30.5 4884.8 9.7 4875.0 7.2 9.8 4875.0 7.2 9.7 4875.0 7.2 9.5 4875.3 6.9 8.8 4875.9 6.3 8.6 4876.1 6.1 14 4917.4 13.5 4918.5 18.7 4899.8 17.6 19.8 4899.7 17.6 18.7 4899.8 17.6 18.7 4899.8 17.5 18.7 4899.8 17.5 18.6 4899.9 17.5 15 4906.9 40.0 4910.2 10.9 4899.3 7.6 11.0 4899.2 7.6 11.0 4899.2 7.6 10.9 4899.3 7.6 10.9 4899.3 7.6 10.8 4899.4 7.5 16 4880.0 22.0 4881.8 9.8 4872.0 8.0 9.9 4872.0 8.1 9.7 4872.1 7.9 9.4 4872.4 7.6 8.9 4872.9 7.1 8.5 4873.3 6.7 17 4877.5 1.5 4877.7 9.7 4867.9 9.6 9.8 4867.9 9.6 9.6 4868.0 9.5 9.5 4868.1 9.4 9.3 4868.3 9.2 9.2 4868.5 9.0 18 4868.8 24.0 4870.8 9.5 4861.3 7.5 9.5 4861.3 7.5 9.4 4861.5 7.4 9.2 4861.6 7.2 9.0 4861.8 7.0 8.9 4861.9 6.9 FCRID Water Surface Elevations 2019 DATA January 15,2019 February 15,2019 March 21,2019 April 16,2019 May 16,2019 June 11,2019 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water S Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water S Surface Surface Surface Elevation(ft, (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) I (ft,NAVD88) Northeast Wingwall at William Neal Parkway 4855.90 126 10.5 4575.4 127 10.5 4875.4 127 10.5 4875.4 124 10.3 4875.E 116 9.7 4876.2 112 9.3 4876.E Southeast Wingwall 4885.79 124 10.3 4875.5 125 10.4 4875.4 125 10.4 4875.4 122 10.2 4875.E 114 9.5 4576.3 110 9.2 4876.E at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 83 6.9 4874.2 82 6.8 4874.3 83 6.9 4874.2 79 6.6 4874.5 67 5.6 4875.5 67 5.6 4875.5 of Horsetooth Road Boxelder Water Surface Elevations 2019 DATA January 15,2019 February 15,2019 March 21,2019 April 16,2019 May 16,2019 June 11,2019 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Top of CMP-Upstream (Northern Crossing) 4572.84 40.5 3.4 4869.5 41.0 3.4 4869.4 37.0 3.1 4869.8 27.0 2.3 4870.E 27.5 2.3 4870.5 25.0 2.1 4870.8 Top of CMP-Downstream (Northern Crossing) 4873.27 45.0 3.8 4869.5 45.5 3.8 4869.5 41.0 3.4 4869.9 36.5 3.0 4870.2 36.0 3.0 4870.3 34.5 2.9 4870.4 Top of CMP-Upstream 4871.61 36.0 3.0 4868.E 36.0 3.0 4868.E 33.0 2.8 4868.9 26.5 2.2 4869.4 25.5 2.1 4869.5 23.5 2.0 4869.7 (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 38.5 3.2 4868.E 38.5 3.2 4868.E 35.0 2.9 4865.9 29.0 2.4 4869.4 25.5 2.4 4869.4 26.5 2.2 4869.E Northwest Corner of Wingwall 4865.45 34.5 2.9 4862.E 34.5 2.9 4862.E 30.5 2.5 4862.9 25.5 2.1 4863.3 24.0 2.0 4863.5 23.0 1.9 4863.5 Upstream of Drop Structure Southeast Corner of Wingwall 4865.18 49.5 4.1 4861.1 50.0 4.2 4861.0 44.5 3.7 4561.5 40.5 3.4 4861.8 30.0 2.5 4862.7 30.0 2.5 4862.7 Downstream of Drop Structure Western Wall at Check Structure Adjacent to Rigden Reservoir 4864.14 42.3 3.5 4860.6 42.5 3.5 4860.6 39.5 3.3 4860.8 36.5 3.0 4861.1 17.0 1.4 4862.7 17.0 1.4 4862.7 Pond Water Surface Elevations 2019 DATA January 15,2019 February 15,2019 March 21,2019 April 16,2019 May 16,2019 June 11,2019 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface is to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Staff Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Elevation Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage (ft,NAVD88) (ft) (ft) A NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) Staff Gage Located In Southwestern N/A N/A N/A N/A N/A N/A Corner of Pond 4874.49 1.7 2.3 4872.2 2.3 1.7 4872.8 2.3 1.7 4872.8 2.3 1.7 4872.8 (Pond Frozen) (Pond Frozen) (Pond Frozen) (Pond Frozen) (Pond Frozen) (Pond Frozen) Page 2 of 6 TABLE A.4.1:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 1 Monitoring Well Data 2019 DATA(Continued) July 17,2019 August 16,2019 September 17,2019 October 15,2019 November 15,2019 December 15,2019 Ground Depth from Tap of Distance to Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Monitoring Elevation Ground to Top PVC/Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Well R at Well of PVC/Well Elevation from Tap of Elevation from Ground from Top of Elevation from Ground from Tap of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground (ft,NAVD88) (inches) (ft,NAVD88) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 12.8 4875.3 10.7 13.2 4875.0 11.0 13.4 4874.8 11.3 13.8 4874.4 11.6 14.1 4874.0 12.0 14.2 4874.0 12.1 2 4875.8 30.5 4878.4 7.5 4870.9 4.9 7.6 4870.8 5.1 7.8 4870.6 5.3 7.9 4870.5 5.3 8.9 4869.5 6.3 8.9 4869.5 6.3 3 4873.2 8.0 4873.9 N/A N/A N/A 4.1 4869.8 3.4 4.2 4869.6 3.6 4.3 4869.6 3.6 5.1 4868.7 4.5 N/A N/A N/A 4 4885.2 16.0 4886.5 10.1 4876.5 8.7 10.4 4876.2 9.0 11.2 4875.3 9.9 11.9 4874.7 10.5 12.0 4974.6 10.6 12.0 4874.5 10.7 5 4881.5 33.5 4884.3 11.6 4872.6 8.8 11.9 4872.4 9.1 12.5 4871.8 9.7 12.8 4871.5 10.0 13.2 4871.1 10.4 13.3 4871.0 10.5 6 4873.8 29.5 4876.2 7.7 4868.5 5.2 7.9 4868.3 5.4 8.1 4868.1 5.7 8.2 4868.0 5.8 9.1 4867.1 6.6 9.1 4867.1 6.7 7 4883.7 49.0 4887.8 11.2 4876.6 7.1 11.5 4876.4 7.4 12.7 4875.2 8.6 13.1 4874.8 9.0 13.1 4874.7 9.1 13.2 4874.7 9.1 8 4880.5 28.0 4882.8 11.9 4870.9 9.5 12.1 4870.7 9.8 12.7 4870.1 10.4 13.1 4869.7 10.7 13.4 4869.4 11.1 13.5 4869.3 11.2 9 4873.4 24.5 4875.4 8.5 4867.0 6.4 8.8 4866.7 6.7 9.0 4866.4 7.0 9.1 4866.3 7.1 9.8 4865.6 7.8 9.9 4865.6 7.8 10 4870.6 38.0 4873.7 8.9 4864.8 5.8 9.1 4864.6 6.0 9.5 4864.2 6.3 9.6 4864.1 6.4 10.1 4863.6 6.9 10.1 4863.6 7.0 11 4877.6 26.0 4879.8 11.2 4868.6 9.0 11.4 4868.4 9.2 11.9 4867.9 9.7 12.2 4867.6 10.0 12.5 4867.3 10.3 12.5 4867.3 10.4 12 4880.7 27.0 4882.9 8.5 4874.5 6.2 8.8 4874.1 6.5 9.9 4873.0 7.6 10.4 4872.5 8.2 10.6 4872.3 9.3 10.6 4872.3 8.4 13 4882.2 30.5 4884.8 7.5 4877.2 5.0 7.8 4877.0 5.2 8.9 4875.8 6.4 9.5 4875.3 7.0 9.6 4875.2 7.1 9.6 4875.1 7.1 14 4917.4 13.5 4918.5 18.5 4899.9 17.4 18.7 4899.8 17.5 18.7 4899.7 17.6 18.8 4899.7 17.7 18.8 4899.7 17.6 18.7 4899.8 17.6 15 4906.9 40.0 4910.2 10.8 4899.4 7.4 11.0 4899.2 7.6 11.0 4899.2 7.7 10.9 4899.3 7.6 10.9 4899.3 7.6 10.8 4899.4 7.5 16 4880.0 22.0 4881.8 7.4 4874.5 5.5 7.9 4873.9 6.1 9.1 4872.8 7.2 9.6 4872.3 7.7 9.6 4872.2 7.8 9.7 4872.2 7.8 17 4877.5 1.5 4877.7 8.7 4869.0 8.6 8.9 4868.8 8.7 9.4 4868.3 9.2 9.8 4867.8 9.7 9.7 4868.0 9.6 9.7 4867.9 9.6 18 4868.8 24.0 4870.8 9.0 4861.9 7.0 8.9 4862.0 6.9 9.2 4861.6 7.2 9.2 4861.6 7.2 9.5 4861.4 7.5 9.5 4861.4 7.5 FCRID Water Surface Elevations 2019 DATA(Continued) July 17,2019 August 16,2019 September 15,2019 October 15,2019 November 15,2019 December 15,2019 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation(ft, (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Northeast Wingwall 4885.90 104 8.7 4877.2 109 9.1 4876.8 123 10.3 4875.7 126 10.5 4875.4 125 10.4 4875.5 126 10.5 4875.4 at William Neal Parkway Southeast Wingwall 4885.79 102 8.5 4877.3 107 8.9 4876.9 121 10.1 4875.7 124 10.3 4875.5 123 10.3 4875.5 124 10.3 4875.5 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 56 4.6 4876.5 58 4.8 4876.3 77 6.4 4874.7 81 6.8 4874.4 82 6.8 4874.3 82 6.8 4874.3 of Horsetooth Road Boxelder Water Surface Elevations 2019 DATA(Continued) July 17,2019 August 16,2019 September 15,2019 October 15,2019 November 15,2019 December 15,2019 Top of Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance Distance to Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Top of CMP-Upstream (Northern Crossing) 4872.84 22.3 1.9 4871.0 25.0 2.1 4870.8 26.5 2.2 4870.E 27.5 2.3 4870.5 40.0 3.3 4869.5 39.5 3.3 4869.5 Top of CMP-Downstream (Northern Crossing) 4873.27 31.0 2.6 4870.7 32.5 2.7 4870.E 34.0 2.8 4870.4 35.0 2.9 4870.4 44.5 3.7 4869.E 44.3 3.7 4869.E Top of CMP-Upstream 4871.61 19.3 1.6 4870.0 22.0 1.8 4869.8 23.0 1.9 4869.7 23.5 2.0 4869.7 38.0 3.2 4868.4 38.0 3.2 4868.4 (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 22.3 1.9 4869.9 24.5 2.0 4869.7 25.5 2.1 4869.E 26.5 2.2 4869.E 40.0 3.3 4868.4 39.8 3.3 4868.5 Northwest Corner of Wingwall 4865.45 21.5 1.8 4863.7 23.0 1.9 4863.5 22.5 1.9 4863.E 24.0 2.0 4863.5 34.0 2.8 4862.E 33.5 2.8 4862.7 Upstream of Drop Structure Southeast Corner of Wingwall 4865.18 29.0 2.4 4862.8 30.5 2.5 4862.E 37.0 3.1 4862.1 39.0 3.3 4861.9 50.0 4.2 4861.0 50.5 4.2 4861.0 Downstream of Drop Structure Western Wall at Check Structure Adjacent to Rigden Reservoir 4864.14 17.5 1.5 4862.7 18.0 1.5 4862.6 33.5 2.8 4861.3 34.0 2.8 4861.3 42.0 3.5 4860.6 42.3 3.5 4860.6 Pond Water Surface Elevations 2019 DATA(Continued) July 17,2019 August 16,2019 September 15,2019 October 15,2019 November 15,2019 December 15,2019 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Staff Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Elevation Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) Staff Gage Located In Southwestern N/A N/A N/A Corner of Pond 4874.49 2.9 1.1 4873.4 2.6 1.4 4873.1 2.5 1.5 4873.0 2.2 1.8 4872.7 1.5 2.5 4872.0 (Pond Frozen) (Pond Frozen) (Pond Frozen) Page 3 of 6 TABLE A.4.1:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 1 Monitoring Well Data 2020 DATA January 17,2020 February 20,2020 March 18,2020 April 24,2020 May 20,2020 June 17,2020 Ground Depth from Tap of Distance to Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Distance to Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Monitoring Elevation Ground to Top PVC/Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Well R at Well of PVC/Well Elevation from Tap of Elevation from Ground from Top of Elevation from Ground from Tap of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground (ft,NAVD88) (inches) (ft,NAVD88) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 14.3 4873.9 12.2 14.2 4874.0 12.0 14.3 4873.8 12.2 13.9 4874.3 11.8 13.7 4874.5 11.6 13.7 4874.5 11.6 2 4875.8 30.5 4878.4 8.9 4869.5 6.3 8.9 4869.5 6.3 8.9 4869.5 6.3 8.9 4869.5 6.4 7.9 4870.5 5.3 7.7 4870.7 5.2 3 4873.2 8.0 4873.9 5.2 4868.E 1 4.6 5.3 4868.E 1 4.6 5.2 4868.6 4.6 N/A N/A N/A 4.3 4869.6 3.6 3.9 4870.0 3.2 4 4885.2 16.0 4886.5 12.1 4874.5 10.7 12.1 4874.5 10.7 12.0 4874.6 10.6 11.8 4874.8 10.4 11.8 4874.8 10.4 11.5 4875.1 10.2 5 4881.5 33.5 4884.3 13.3 4871.0 10.5 13.3 4870.9 10.5 13.2 4871.0 10.4 12.7 4871.6 9.9 12.7 4871.6 9.9 12.6 4871.7 9.8 6 4873.8 29.5 4876.2 9.1 4867.1 6.6 9.1 4867.1 6.7 9.1 4867.1 6.6 8.3 4868.0 5.8 8.2 4868.0 5.7 8.0 4868.2 5.6 7 4883.7 49.0 4887.8 13.3 4874.6 9.2 13.2 4874.6 9.2 13.2 4874.6 9.2 13.1 4874.8 9.0 13.0 4874.9 8.9 12.8 4875.1 8.7 8 4880.5 28.0 4882.8 13.5 4869.4 11.1 13.5 4869.3 11.2 13.4 4869.4 11.1 13.0 4869.9 10.6 12.9 4869.9 10.6 12.8 4870.0 10.4 9 4873.4 24.5 4875.4 9.8 4865.6 7.8 9.8 4865.6 7.8 9.8 4865.7 7.7 9.1 4866.3 7.1 9.0 4866.5 6.9 9.0 4866.5 6.9 10 4870.6 38.0 4873.7 10.0 4863.7 6.9 10.1 4863.6 6.9 10.0 4863.8 6.8 9.4 4864.3 6.3 9.3 4864.4 6.2 9.4 4864.4 6.2 11 4877.6 26.0 4879.8 12.5 4867.3 10.3 12.5 4867.3 10.4 12.4 4867.4 10.3 12.1 4867.8 9.9 12.0 4867.8 9.8 11.9 4867.9 9.7 12 4880.7 27.0 4882.9 10.7 4872.3 8.4 10.7 4872.2 8.4 10.7 4872.2 8.4 10.4 4872.5 8.1 10.3 4872.6 8.1 10.1 4872.9 7.8 13 4882.2 30.5 4884.8 9.7 4875.1 7.2 9.8 4875.0 7.2 9.7 4875.0 7.2 9.5 4875.3 7.0 9.5 4875.3 6.9 9.2 4875.6 6.6 14 4917.4 13.5 4918.5 18.7 4899.8 17.6 18.6 4899.9 17.5 18.7 4899.8 17.6 18.7 4899.8 17.6 18.6 4899.9 17.5 18.6 4899.9 17.5 15 4906.9 40.0 4910.2 10.9 4899.3 7.5 10.9 4899.3 7.6 11.0 4899.2 7.6 10.8 4899.4 7.5 10.8 4899.4 7.5 10.8 4899.4 7.5 16 4880.0 22.0 4881.8 9.8 4872.1 7.9 9.8 4872.1 7.9 9.8 4872.1 7.9 9.4 4872.4 7.6 9.4 4872.4 7.6 9.2 4872.7 7.3 17 4877.5 1.5 4877.7 9.7 4867.9 9.6 9.7 4867.9 9.6 9.7 4868.0 9.6 9.5 4868.1 9.4 9.5 4868.1 9.4 9.5 4868.2 9.3 18 4868.8 24.0 4870.8 9.5 4861.4 7.5 9.4 4861.4 7.4 9.2 4861.6 7.2 9.0 4861.8 7.0 9.0 4861.8 7.0 9.1 4861.7 7.1 FCRID Water Surface Elevations 2020 DATA January 17,2020 February 20,2020 March 18,2020 April 24,2020 May 20,2020 June 17,2020 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water S Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water S Surface Surface Surface Elevation(ft, (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) I (ft,NAVD88) Northeast Wingwall 4885.90 127 10.6 4875.3 126 10.5 4875.4 126 10.5 4875.4 126 10.5 4875.4 124 10.3 4875.6 122 10.2 4875.7 at William Neal Parkway Southeast Wingwall 4885.79 125 10.4 4875.4 124 10.3 4875.5 125 10.4 4875.4 124 10.3 4875.5 122 10.2 4875.E 121 10.0 4875.7 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 83 6.9 4874.2 81 6.8 4874.3 83 6.9 4874.2 81 6.8 4874.4 78 6.5 4874.6 76 6.3 4874.8 of Horsetooth Road Boxelder Water Surface Elevations 2020 DATA January 17,2020 February 20,2020 March 18,2020 April 24,2020 May 20,2020 June 17,2020 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Top of CMP-Upstream (Northern Crossing) 4572.84 39.5 3.3 4869.5 40.0 3.3 4869.5 39.5 3.3 4869.5 27.0 2.3 4870.E 25.5 2.1 4870.7 22.5 1.9 4871.0 Top of CMP-Downstream (Northern Crossing) 4873.27 44.3 3.7 4869.E 44.5 3.7 4869.E 44.5 3.7 4869.E 35.0 2.9 4870.4 34.5 2.9 4870.4 32.0 2.7 4870.E Top of CMP-Upstream 4871.61 38.0 3.2 4868.4 38.0 3.2 4868.4 38.0 3.2 4868.4 25.3 2.1 4869.5 23.8 2.0 4869.E 21.0 1.8 4869.9 (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 40.0 3.3 4868.4 40.0 3.3 4868.4 40.0 3.3 4868.4 27.8 2.3 4869.5 26.5 2.2 4869.E 24.0 2.0 4869.8 Northwest Corner of Wingwall 4865.45 33.5 2.8 4862.7 34.0 2.8 4862.E 34.3 2.9 4862.E 25.8 2.1 4863.3 24.5 2.0 4863.4 24.0 2.0 4863.5 Upstream of Drop Structure Southeast Corner of Wingwall 4865.18 50.0 4.2 4861.0 50.0 4.2 4861.0 50.0 4.2 4561.0 39.5 3.3 4861.9 35.0 2.9 4862.3 31.0 2.6 4862.E Downstream of Drop Structure Western Wall at Check Structure Adjacent to Rigden Reservoir 4864.14 42.5 3.5 4860.6 42.5 3.5 4860.6 42.0 3.5 4860.6 35.0 2.9 4861.2 20.8 1.7 4862.4 18.0 1.5 4862.6 Pond Water Surface Elevations 2020 DATA January 17,2020 February 20,2020 March 18,2020 April 24,2020 May 20,2020 June 17,2020 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface is to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Staff Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Elevation Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage (ft,NAVD88) (ft) (ft) A NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) Staff Gage Located In Southwestern N/A N/A N/A N/A N/A N/A Corner of Pond 4874.49 1.5 2.5 4572.0 2.4 1.6 4872.9 2.6 1.4 4873.1 2.4 1.6 4872.9 (Pond Frozen) (Pond Frozen) (Pond Frozen) (Pond Frozen) (Pond Frozen) (Pond Frozen) Page 4 of 6 TABLE A.4.1:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 1 Monitoring Well Data 2020 DATA(Continued) July 22,2020 August 21,2020 September 15,2020 October 12,2020 November 20,2020 December 15,2020 Ground Depth from Tap of Distance to Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Monitoring Elevation Ground to Top PVC/Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Well R at Well of PVC/Well Elevation from Tap of Elevation from Ground from Top of Elevation from Ground from Tap of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground (ft,NAVD88) (inches) (ft,NAVD88) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 13.6 4874.6 11.4 13.7 4874.4 11.6 13.9 4874.2 11.8 14.5 4873.6 12.4 14.2 4873.9 12.1 14.3 4873.8 12.2 2 4875.8 30.5 4878.4 7.7 4870.7 5.1 7.9 4870.5 5.3 8.3 4870.1 5.8 8.2 4870.2 5.6 8.6 4869.8 6.1 8.7 4869.7 6.2 3 4873.2 8.0 4873.9 4.2 4869.7 3.5 4.3 4869.5 3.7 4.5 4869.3 3.9 4.6 4869.3 3.9 5.0 4868.8 4.4 5.1 4868.8 4.4 4 4885.2 16.0 4886.5 11.0 4875.5 9.7 11.0 4875.6 9.6 11.7 4874.8 10.4 12.0 4874.5 10.7 12.1 4874.4 10.8 12.0 4874.5 10.7 5 4881.5 33.5 4884.3 12.3 4872.0 9.5 12.4 4871.9 9.6 12.9 4871.4 10A 13.1 4871.2 10.3 13.3 4870.9 10.5 13.3 4871.0 10.5 6 4873.8 29.5 4876.2 7.9 4868.3 5.5 8.1 4868.1 5.7 8.6 4867.6 6.1 8.5 4867.7 6.0 8.9 4867.3 6.5 9.0 4867.2 6.6 7 4883.7 49.0 4887.8 12.1 4875.7 8.1 11.9 4875.9 7.8 13.0 4874.8 8.9 13.3 4874.6 9.2 13.3 4874.5 9.3 13.2 4874.7 9.1 8 4880.5 28.0 4882.8 12.5 4870.3 10.2 12.6 4870.2 10.2 13.2 4869.7 10.8 13.3 4869.5 11.0 13.5 4869.3 11.2 13.5 4869.4 11.1 9 4873.4 24.5 4875.4 8.9 4866.5 6.9 9.1 4866.3 7.1 9.5 4866.0 7.4 9.4 4866.0 7.4 9.8 4865.7 7.7 9.8 4865.7 7.7 10 4870.6 38.0 4873.7 9.3 4864.4 6.2 9.4 4864.3 6.3 9.9 4863.9 6.7 9.8 4863.9 6.7 10.1 4863.7 6.9 10.0 4863.7 6.9 11 4877.6 26.0 4879.8 11.8 4868.0 9.6 11.8 4868.0 9.6 12.2 4867.6 10.0 12.3 4867.5 10.2 12.5 4867.4 10.3 12.5 4867.3 10.3 12 4880.7 27.0 4882.9 9.5 4873.4 7.3 9.3 4873.6 7.1 10.3 4872.6 8.1 10.7 4872.3 8.4 10.7 4872.2 8.5 10.6 4872.3 8.3 13 4882.2 30.5 4884.8 8.6 4876.2 6.0 8.3 4876.5 5.8 9.4 4875.4 6.9 9.7 4875.1 7.1 9.8 4875.0 7.2 9.6 4875.2 7.1 14 4917.4 13.5 4918.5 18.7 4899.7 17.6 18.8 4899.7 17.7 18.9 4899.6 17.8 18.9 4899.6 17.8 18.9 4899.6 17.8 18.9 4899.6 17.8 15 4906.9 40.0 4910.2 11.1 4899.1 7.8 11.2 4899.0 7.9 11.1 4899.1 7.8 11.2 4899.0 7.9 11.0 4899.2 7.7 11.0 4899.2 7.7 16 4880.0 22.0 4881.8 8.8 4873.1 6.9 8.6 4873.2 6.8 9.4 4872.4 7.6 9.8 4872.0 8.0 9.8 4872.1 7.9 9.6 4872.2 7.8 17 4877.5 1.5 4877.7 9.3 4868.3 9.2 9.3 4868.4 9.1 9.8 4867.8 9.7 9.8 4867.9 9.7 9.8 4867.9 9.7 9.7 4867.9 9.6 18 4868.8 24.0 4870.8 9.1 4861.8 7.1 9.1 4861.8 7.1 9.2 4861.6 7.2 9.3 4861.5 7.3 9.4 4861.4 7.4 9.4 4861.4 7.4 FCRID Water Surface Elevations 2020 DATA(Continued) July 22,2020 August 21,2020 September 15,2020 October 12,2020 November 20,2020 December 15,2020 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation(ft, (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation NAVD88) (ft,NAVD88) I (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Northeast Wingwall 4885.90 117 9.8 4876.2 117 9.7 4876.2 128 10.7 4875.2 126 10.5 4875.4 128 10.7 4875.2 125 10.4 4875.5 at William Neal Parkway Southeast Wingwall 4885.79 115 9.6 4876.2 114 9.5 4876.3 127 10.5 4875.2 125 10.4 4875.4 127 10.5 4875.2 123 10.3 4875.5 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 65 5.4 4875.7 63 5.3 4875.9 81 6.7 4874.4 82 6.8 4874.3 85 7.0 4874.1 78 6.5 4874.6 of Horsetooth Road Boxelder Water Surface Elevations 2020 DATA(Continued) July 22,2020 August 21,2020 September 15,2020 October 12,2020 November 20,2020 December 15,2020 Top of Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance Distance to Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water to Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) A NAVD88) (ft,NAVD88) Top of CMP-Upstream (Northern Crossing) 4572.84 23.3 1.9 4870.9 25.3 2.1 4870.7 33.0 2.8 4870.1 30.0 2.5 4870.3 36.5 3.0 4869.8 38.3 3.2 4869.7 Top of CMP-Downstream (Northern Crossing) 4873.27 32.0 2.7 4870.E 34.0 2.8 4870.4 39.5 3.3 4870.0 38.0 3.2 4870.1 42.0 3.5 4869.8 43.0 3.6 4869.7 Top of CMP-Upstream 4871.61 21.3 1.8 4869.8 24.0 2.0 4869.E 30.0 2.5 4869.1 27.5 2.3 4869.3 34.0 2.8 4868.8 36.5 3.0 4868.E (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 24.3 2.0 4869.7 26.8 2.2 4869.5 32.0 2.7 4869.1 30.0 2.5 4869.3 36.5 3.0 4868.7 38.5 3.2 4868.E Northwest Corner of Wingwall 4865.45 23.8 2.0 4863.5 24.5 2.0 4863.4 29.5 2.5 4863.0 27.3 2.3 4863.2 32.0 2.7 4862.8 33.0 2.8 4862.7 Upstream of Drop Structure Southeast Corner of Wingwall 4865.18 30.0 2.5 4862.7 32.0 2.7 4862.5 44.0 3.7 4561.5 41.0 3.4 4861.8 47.0 3.9 4861.3 49.0 4.1 4861.1 Downstream of Drop Structure Western Wall at Check Structure Adjacent to Rigden Reservoir 4864.14 17.5 1.5 4862.7 17.0 1.4 4862.7 37.5 3.1 4861.0 36.0 3.0 4861.1 39.0 3.3 4860.9 41.0 3.4 4860.7 Pond Water Surface Elevations 2020 DATA(Continued) July 22,2020 August 21,2020 September 15,2020 October 12,2020 November 20,2020 December 15,2020 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Staff Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Elevation Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage (ft,NAVD88) (ft) (ft) (ft, NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) Staff Gage Located In Southwestern N/A N/A N/A Corner of Pond 4874.49 2.5 1.5 4873.0 2.2 1.8 4872.7 1.9 2.2 4872.3 2.2 1.8 4872.7 1.8 2.3 4872.2 (Pond Frozen) (Pond Frozen) (Pond Frozen) Page 5 of 6 TABLE A.4.1:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 1 Monitoring Well Data 2021 DATA STATISTICS January 13,2021 February 23,2021 March 24,2021 April 21,2021 May 20,2021 Ground Depth from Tap of Distance to Groundwater Groundwater Groundwater Depth to Distance to Depth to Distance to Depth to Distance to undwater Gr o Depth to Distance to Groundwater Depth to Maximum Average Minimum Average Depth to Monitoring Elevation Ground to Top PVC/Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Well R at Well of PVC/Well Elevation from Tap of Elevation from Ground from Top of Elevation from Ground from Tap of Elevation from Ground from Top of Elevation from Ground from Top of Elevation from Ground Surface Elevation Surface Elevation Surface Elevation from Ground (ft,NAVD88) (inches) (ft,NAVD88) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 14.4 4873.8 12.3 16.2 4872.0 14.0 16.2 4872.0 14.0 16.4 4871.8 14.3 15.1 4873.1 13.0 4875.3 4874.0 4871.8 12.1 2 4875.8 30.5 4878.4 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 4870.9 4870.1 4869.5 5.8 3 4873.2 8.0 4873.9 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 4870.0 4869.2 4868.6 4.0 4 4885.2 16.0 4886.5 12.1 4874.4 10.8 12.5 4874.1 11.1 12.3 4874.3 10.9 12.4 4874.1 11.1 11.9 4874.6 10.6 4876.5 4874.8 4874.1 10.4 5 4881.5 33.5 4884.3 13.3 4871.0 10.5 13.8 4870.5 11.0 13.7 4870.6 10.9 13.7 4870.6 10.9 130 4871.3 10.2 4872.6 4871.3 4870.5 10.1 6 4873.8 29.5 4876.2 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 4868.5 4867.7 4867.1 6.1 7 4883.7 49.0 4887.8 13.3 4874.5 9.2 13.4 4874.4 9.3 13.2 4874.6 9.1 13.3 4874.5 9.2 13.0 4874.8 9.0 4876.6 4875.0 4874.4 8.8 S 4880.5 28.0 4882.8 13.5 4869.3 11.1 13.7 4869.2 11.3 13.4 4869.4 11.1 13.5 4869.4 11.1 13.0 4869.8 10.6 4870.9 4869.7 4869.2 10.8 9 4873.4 24.5 4875.4 9.7 4865.7 7.7 9.9 4865.6 7.8 9.6 4865.9 7.5 9.5 4866.0 7.4 9.0 4866.4 7.0 4867.0 4866.0 4865.5 7.4 10 4870.6 38.0 4873.7 10.0 4863.8 6.8 10.1 4863.7 6.9 9.8 4864.0 6.6 9.7 4864.0 6.6 9.5 4864.2 6.3 4864.8 4864.0 4863.6 6.6 11 4877.6 26.0 4879.8 12.5 4867.3 10.3 12.6 4867.2 10.4 12.3 4867.5 10.1 12.4 4867.4 10.2 11.9 4868.0 9.7 4868.6 4867.6 4867.2 10.0 12 4880.7 27.0 4882.9 10.7 4872.2 8.5 10.9 4872.1 8.6 10.5 4872.4 8.3 10.7 4872.2 8.4 10.3 4872.6 8.1 4874.5 4872.7 4872.1 8.0 13 4882.2 30.5 4884.8 9.8 4875.0 7.2 9.9 4874.8 7.4 9.6 4875.2 7.1 9.8 4875.0 7.2 9.4 4875.3 6.9 4877.2 4875.5 4874.8 6.8 14 4917.4 13.5 4918.5 18.9 4899.6 17.8 18.9 4899.6 17.8 18.9 4899.6 17.8 18.9 4899.6 17.7 18.3 4900.1 17.2 4900.1 4899.8 4899.6 17.6 15 4906.9 40.0 4910.2 11.0 4899.2 7.7 11.1 4899.1 7.7 10.9 4899.3 7.5 10.9 4899.3 7.6 10.6 4899.6 7.2 4899.6 4899.3 4899.0 7.6 16 4880.0 22.0 4881.8 9.8 4872.0 8.0 10.0 4871.9 8.1 9.5 4872.4 7.6 9.7 4872.1 7.9 9.3 4872.6 7.4 4874.5 4872.5 4871.9 7.5 17 4877.5 1.5 4877.7 9.7 4867.9 9.6 9.8 4867.9 9.6 9.5 4868.2 9.4 9.6 4868.0 9.5 9.5 4868.2 9.4 4869.0 4868.1 4867.8 9.4 18 4868.8 24.0 4870.8 9.4 4861.5 7.4 9.4 4861.5 7.4 9.3 4861.5 7.3 9.3 4861.5 7.3 9.2 4861.7 7.2 4862.0 4861.6 4861.3 7.3 FCRID Water Surface Elevations 2021 DATA STATISTICS January 13,2021 February 23,2021 March 24,2021 April 21,2021 May 15,2021 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Maximum Ditch Average Ditch Minimum Ditch Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Wall/Pipe Surface Surface Surface Surface Surface Water Surface Water Surface Water Surface Location Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Elevation(ft, (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation Elevation Elevation Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Northeast Wingwall 4885.90 127 10.5 4875.4 127 10.5 4875.4 126 10.5 4875.4 127 10.6 4875.3 125 10.4 4875.5 4877.5 4875.7 4875.2 at William Neal Parkway Southeast Wingwall 4885.79 125 10.4 4875.4 125 10.4 4875.4 124 10.3 4875.5 125 10.4 4875.4 123 10.3 4875.5 4877.E 4875.8 4575.2 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 82 6.8 4874.3 84 7.0 4874.1 81 6.8 4874.4 84 7.0 4874.1 82 6.8 4874.3 4877.2 4874.7 4874.1 of Horsetooth Road Boxelder Water Surface Elevations 2021 DATA STATISTICS January 13,2021 February 23,2021 March 24,2021 April 21,2021 May 15,2021 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Maximum Ditch Average Ditch Minimum Ditch Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Wall/Pipe Surface Surface Surface Surface Surface Water Surface Water Surface Water Surface Location Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation Elevation Elevation Elevation (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Top of CMP-Upstream (Northern Crossing) 4572.84 36.5 3.0 4869.8 33.5 2.8 4870.0 39.0 3.3 4869.E 33.5 2.8 4870.0 27.5 2.3 4870.5 4871.0 4570.2 4869.4 Top of CMP-Downstream (Northern Crossing) 4873.27 41.0 3.4 4869.9 41.5 3.5 4869.8 43.5 3.6 4869.E 40.0 3.3 4869.9 36.5 3.0 4870.2 4870.7 4870.0 4869.4 Top of CMP-Upstream 4871.61 33.5 2.8 4868.8 34.5 2.9 4868.7 37.5 3.1 4868.5 31.5 2.6 4869.0 26.5 2.2 4869.4 4870.0 4869.1 4868.4 (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 35.5 3.0 4868.8 40.0 3.3 4868.4 39.5 3.3 4868.5 34.0 2.8 4868.9 29.3 2.4 4869.3 4869.9 4869.1 4868.4 Northwest Corner of Wingwall 4865.45 31.0 2.6 4862.9 34.0 2.8 4862.E 34.0 2.8 4862.E 30.0 2.5 4863.0 24.5 2.0 4863.4 4863.7 4863.1 4862.E Upstream of Drop Structure Southeast Corner of Wingwall 4865.18 45.5 3.8 4861.4 49.0 4.1 4861.1 49.5 4.1 4861.1 44.0 3.7 4861.5 42.0 3.5 4861.7 4862.8 4861.7 4861.0 Downstream of Drop Structure Western Wall at Check Structure Adjacent to Rigden Reservoir 4864.14 37.8 3.1 4861.0 41.0 3.4 4860.7 40.5 3.4 4860.8 37.3 3.1 4861.0 36.0 3.0 4861.1 4862.7 4861.3 4860.E Pond Water Surface Elevations 2021 DATA STATISTICS January 13,2021 February 23,2021 March 24,2021 April 21,2021 May 15,2021 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface is to Water Surface Distance to Maximum Pond Average Pond Minimum Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Staff Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Water Surface Water Surface Pond Water Location Elevation Elevation Elevation Elevation Elevation Elevation Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Elevation Elevation Surface Elevation (ft,NAVD88) (ft) (ft) A NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Staff Gage Located In Southwestern N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A Corner of Pond 4874.49 (Pond (Pond (Pond (Pond (Pond (Pond (Pond (Pond (Pond (Pond (Pond (Pond 4873.4 4872.6 4871.8 (Pond Frozen) (Pond Frozen) (Pond Frozen) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Page 6 of 6 TABLE A.4.2:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 2 Monitoring Well Data 2022 DATA 2023 DATA October 20,2022 November 28,2022 December 19,2022 January 27,2023 February 20,2023 March 15,2023 April 24,2023 May I5,2023 Depth from Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Ground Top of Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Monitoring top of Well to Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Elevation Elevation(k, Elevation Elevation Elevation Elevation Elevation Elevation Elevation Elevation Well N Ground from Top of from Ground from Top of from Ground from lop of from Ground from Top of from Ground from Top of from Ground from Top of from Ground from Top of from Ground from Top of from Ground (ft,NAVD88) inches NAVD88) Well(ft) (ft,NAVD88) Surface(ft Well ft (k,NAVD88) Surface(ft) Well ft (ft,NAVD88) Surface(ft) Well ft (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft) Well ft lk,NAVD88) Surface[ft) Well(ft) (k,NAVD88) Surface(ft) 1 4886.0 25.5 4888.2 13.0 4875.2 10.9 13.2 4874.9 11.1 13.3 4874.9 11.1 13.2 4875.0 11.0 13.1 4875.0 11.0 13.2 4875.0 11.0 13.0 4875.2 10.9 12.6 4875.6 10.4 4 4885.2 16.0 4886.5 11.5 4875.0 10.2 12.0 4874.6 10.6 12.0 4874.5 10.7 12.0 4874.5 10.7 12.0 4874.6 10.6 11.9 4874.6 10.6 11.7 4874.8 10.4 11.3 4875.3 9.9 5 4881.5 33.5 4884.3 12.9 4871.4 10.1 13.4 4870.9 10.6 13.4 4870.9 10.6 13.3 4871.0 10.5 13.3 4871.0 10.5 13.3 4871.0 10.5 12.9 4871.4 10.1 12.6 4871.7 9.8 7 4883.7 49.0 1 4887.8 12.7 4875.1 8.6 1 13.2 4874.7 9.1 13.2 4874.6 9.1 13.3 4874.6 9.2 13.2 4874.7 1 9.1 13.2 4874.7 9.1 1 13.0 4874.8 8.9 12.6 4875.3 8.5 8 4880.5 28R 4882.8 13.3 4869.5 11.0 133 4869.2 11.3 13.7 4869.1 11.4 13.7 4869.2 11.3 13.6 4869.2 11.3 13.6 4869.2 11.3 13.3 4869.6 10.9 12.9 4869.9 10.6 9 4873.4 24.5 4875.4 10.1 4865.3 8.1 10.5 4864.9 8.5 10.5 4864.9 8.5 10.5 4865.0 8.4 10.5 4865.0 8.4 10.4 4865.0 8.4 9.9 4865.5 7.9 9.8 4865.7 7.7 10 4870.6 38.0 4873.7 10.1 4863.6 6.9 10.4 4863.3 7.3 10.5 4863.3 7.3 103 4863.4 7.1 10.4 4863.4 7.2 10.3 4863.4 7.1 9.9 4863.8 6.8 9.8 4963.9 6.6 11 4877.6 26.0 4879.8 12.5 4867.3 10.3 12.6 4867.2 10.5 12.7 4867.1 10.6 12.8 4867.1 10.6 12.7 4867.1 10.6 12.7 4867.1 10.5 12.5 4867.3 10.3 11.8 4868.0 9.7 12 4880.7 27.0 4882.9 10.3 4872.7 80 10.7 4872.2 8.4 10.8 4872.1 8.5 10.8 4872.2 8.5 10.6 4872.3 8.4 10.7 4872.2 8A 10.3 4872.6 8.1 9.8 4873.1 7.6 13 4882.2 30.5 4884.8 9.1 4875.7 6.5 9.6 4875.2 7.1 9.7 4875.0 7.2 9.7 4875.0 7.2 9.7 4875.1 7.1 9.9 4874.9 7.3 9.4, 4875.3 6.9 8.9 4875.9 6.3 14 4917.4 13.5 4918.5 19.1 4899.4 17.9 19.0 4899.5 17.9 18.6 4899.9 17.4 18.5 4900.0 17.4 18.5 4900.0 17.4 18.5 4900.0 17.4 18.4 4900.0 17.3 18.3 4900.2 17.2 15 4906.9 40.0 4910.2 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 16 4880.0 22.0 1 4881.8 9.4 4872.4 1 7.6 9.8 4872.1 7.9 9.8 4872.0 8.0 1 9.8 4872.1 7.9 9.7 1 4872.2 7.8 9.7 4872.1 1 79 9.3 4872.6 7.4 1 8.7 4873.2 1 6.8 17 4877.5 1.5 4877.7 9.6 4868.0 9.5 9.7 4867.9 9.6 9.8 4867.8 9.7 9.7 4867.9 9.6 9.7 4868.0 9.6 9.7 4867.9 9.6 9.5 4868.1 9.4 9.3 4868.4 9.2 18 4868.8 24.0 4870.8 9A 4861.4 74 9.5 4861.3 7.5 9.5 4861.3 7.5 9.3 4861.6 7.3 9.5 4861.4 7.5 9.5 4861.4 7.5 9.3 4861.6 7.3 9.2 4861.6 7.2 19 4876.3 13.1 4877.4 9.8 4867.6 8.7 10.3 4867.2 9.2 10.3 4867.1 9.2 10.3 4867.2 9.2 10.3 4867.1 9.2 10.3 4867.2 9.2 9.9 4867.6 8.8 9.7 4867.7 8.6 20 4877.3 11.8 4878.3 7.3 4871.0 6.4 8.0 4870.4 7.0 8.0 4870.3 7.0 7.9 4870.4 6.9 7.9 48705 6.9 7.8 4870.5 6.8 7.3 4871.0 6.4 7.1 4871.3 6.1 21 4882.3 12.8 4883.3 10.7 4872.6 9.7 11.2 4872.2 10.1 11.2 4872.1 10.1 11.2 4872.2 10.1 11.1 4872.3 10.0 11.1 4872.3 10.0 10.7 4872.6 9.7 10.3 4873.0 9.2 22 4872.7 13.3 4873.8 4.4 4869.4 3.3 4.7 4869.2 3.5 4.7 4869.1 3.6 4.6 4869.2 3.5 4.6 4869.2 3.5 4.6 4869.2 3.5 4.4 4869.4 3.3 4.4 4869.4 3.3 23 4876.4 179 4877.9 6.8 4871.1 5.3 6.7 4871.2 5.2 6.6 4871.3 5.2 6.6 4871.3 5.1 6.6 4871.3 5.1 6.6 4871.4 5.1 6.5 4871.4 5.0 6.7 4871.2 5.2 24 4880.3 37.9 4883.5 10.4 4873.1 7.2 10.3 4873.1 7.2 ICA 4873.1 7.2 10.4 4873.1 7.2 10.4 4873.1 7.2 10.3 4873-2 7.1 10.2 4873.2 7A 10.2 4873.2 7.1 25 4874.2 17.6 4875.7 6.0 4869.7 4.5 6.2 4869.5 4.7 6.2 4869.4 4.8 6.2 4869.5 4.7 6.2 4869.5 4.7 6.2 4869.5 4.7 6.1 4869.6 4.6 6.0 4869.7 4.5 26 4873.4 38.9 4876.7 8.0 4868.7 4.7 8.0 4868.7 4.8 8.1 4868.5 4.9 8.1 4868.6 4.8 8.1 4868.6 4.8 8.0 4868.6 4.8 8.0 4868.7 4.7 7.9 4868.7 4.7 BH 1 4874.2 14.6 4875.4 5.6 4869.8 4.4 5.8 4869.6 4.6 5.8 4869.6 4.6 5.8 4869.6 4.6 5.8 4869.6 4.6 5.8 4869.6 4.6 5.6 4869.8 4.4 5.5 4869.9 4.3 BH 2 4879.6 17.3 4881.0 8.1 4872.9 6.6 8.3 4872.7 6.9 8.4 4872.6 7.0 N/A N/A N/A 8A 4872.6 6.9 8.3 4872.7 6A 8.1 4872.9 6.6 8.0 4873.0 6.6 BH 3 4877.5 33.0 4880.2 75 4872.7 4.8 7.5 4872.8 4.7 7.6 4872.6 4.9 7.5 4872.7 4.8 7.4 4872.8 4.7 7.4 4872.9 4.6 7.4 4872.9 4.6 7.3 4872.9 4.6 SH 4 4873.4 16.6 4874.8 5.3 4869.5 3.9 5.4 4869.4 4.0 5.4 4869.4 4.0 5.4 4869.4 4.0 5.4 4869.4 4.0 SA 4869.4 4.0 5.3 4869.5 3.9 5.2 4869.5 3.8 BH 5 4873.E 2.9 4874.1 4.6 4869.5 4.4 4.7 4869.3 4.5 4.7 4869.4 4.4 4.7 4869.4 4.4 4.6 4869.4 4A 4.7 4869.4 4.4 4.6 4869.5 4:3 4.6 4869.5 4.3 FCRID Water Surface Elevations 2022 DATA 2023 DATA October 20,2022 November 28,2022 December 19,2022 January 15,2023 February 15,2023 March 15,2023 April 24,2023 May 15,2023 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance ac Distance a Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Wall/Pipe Surface Surface Surface Surface Surface Surface Surface Surface Location Elevation(k,Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation NAVD88) (in) (R) (ft,NAVD88) (in) (ft) (k,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (k,NAVD88) GN (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) Headwall DS Side Environmental Dr 4884.80 93 7.7 4877.1 101 8A 4876.4 103 8.5 4876.3 103 8.6 4876.2 101 '8.4 4876A 102 85 4876.3 101 8.4 4876.4 95 7.9 4876.9 Northeast Wingwall 4885.90 119 9.9. 4876.0 125 10.4 4875.5 126 10.5 4875.4 127 10.5 4875.4 124 10.3 4875.6 126 10.5 4875.4 124 10.3 4875.6 119 9.9 4876.0 at William Neal Parkway Southeast Wingwall 4885.79 118 9.8 4876.0. 123 10.3 4875.5 124 10.3 4875.5 125 10.4 4875.4 123 10.2 4875.6 124 10.3 4875.5 122 10.2 4875.6 117 9.7 4876.1 at WlIham Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 75 6.2. 4874.9 81 6.8 4874.3 83 6.9 4874.2 83 6.9 4874.2 80 6.7 4874.4 82 6.8 4874.3 80 6.6 4874.5 76 6.3 4874.8 of Horsetooth Road Boxelder Water Surface Elevations 2022 DATA 2023 DATA October 20,2022 November 28,2022 December 19,2022 January 15,2023 February 15,2023 March 15,2023 April 24,2023 May 15,2023 Top of Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Wall/Pipe Surface Surface Surface Surface Surface Surface Surface Surface Location Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Elevation(k, (in) Iftl Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ft) Elevation (in) (ftl Elevation (in) (ft) Elevation NAVD88) (ft,NAVD88) ft,NAVD88) (ft,NAVD88) k,NAVD88) (ft,NAVD88) (k,NAVD88) (ft,NAVD88) (k,NAVD88) Wingwall SE Side Siphon Outlet 4877.65 30.0 2.5 4875.2 38.0 3.2 4874.5 38.0 33 4874.5 38.5. 3.2 4874.4 38.5 3.2 4874A 38.5 3.2 4874A 31.0 2.6 4875.1 29.0 2.4 4875.2 Top of CMP-Upstream 4871.61 27.0 2.3 4869.4 36.3 3.0 4868.6 39.5 3.3 4868.3 395 3.3 4868.3 39,8 3.3 4868.3 39:3 3.3 4868.3 29.5 2.5 4869.2 27.8 2.3 4869.3 (Southern Crossing) Top of CMPDownstream (Southern Crossing) 4871.77 29.8 2.5 4869.3 38.8 3.2 4868.5 41.5 3.5 4868.3 41.8 3.5 4868.3 42.0 3.5 4868.3 42.3 3.5 4868.2 34.0 2.8 4868.9 32.5 2.7 4869.1 Northwest Corner of Wingwall Upstream of Drop Structure 4865.45 25.8 2.1 4863.3 34.3 2.9 4862.6 33.8 2.8 4862.6 33.3 2.8 4862.7 33c0 2.8 4862.7 32.5 2.7 4862.7 25.8 2.1 4863.3 24.0 2.0 4863.5 Southeast Corner of Wingwall Downstream of Drop Structure 4865.18 45.0 18 4861.4 52.5 4.4 4860.8 52.0 4.3 4860.8 52.0 4.3 4860.8 52.0 4.3 4860.8 52.5 4A 4860.9 46.0 3.8 4861.3 44.0 3.7 4861.5 Western Wall at Check Structure 4864,14 37.5 3.1 4861.0 42.8 3.6 4860.6 42.5 3.5 4860.6 42.5 3.5 4860.6 42.8 3.6 4860.6 43.0 16 4860.6 38.5 3:2 4860.9 36.0 3.0 Adjacent to Rigden Reservoir -.1-1 Pond Water Surface Elevations 2022 DATA 2023 DATA October 20,2022 November 28,2022 December 19,2022 January 15,2023 February 15,2023 March 15,2023 April 24,2023 May I5,2023 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Pond Surface Stall Gage Reading on 4.0'Mark an Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Elevation Elevation Elevation(k, Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) ft (ft) (ft,NAVD88) R1 Ikl (ft,NAVD88) (ft) (ft) (ft,NAVD88) (k) (ft) Ift,NAVD88) (ft) ftl (ft,NAVD88) (ft) (ft) (ft,NAVD88) Staff Gage Located on South Bank Near Center 487E Z9 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 1.9 2.1 4874.2 2.1 1.9 4874.4 of Pond IN Installed) IN at Installed) (Not Installed) (Nat Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) IN Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) (Not Installed) INat Installed) Page 1 of 3 TABLE A.4.2:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 2 Monitoring Well Data 2023 DATA July 12,2023 August 2,2023 August 31,2023 September 28,2023 October 25,2023 December 1,2023 December 20,2023 Depth from Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Ground Top of Well Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Monitoring top of Well to Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Elevation Elevation(k, Elevation Elevation Elevation Elevation Elevation Elevation Elevation Well ft Ground from Top of from Ground from Top of from Ground from Top of from Ground from Top of from Ground from Top of from Ground from lop of from Ground from Top of from Ground (ft,NAVD88) Inches NAVD88) Well ft) (ft,NAVD88) Surface(ft Well ft (ft,NAVD88) Surface(ft Well(ft) (ft,NAVD88) Surface[ft) Well ft (ft,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft Well(ft (ft,NAVD88) Surface(ft Well ft (ft,NAVD88) Surface[ft) 1 4886.0 25.5 4888.2 12.0 4876.2 9.8 11.9 4876.2 9.9 12.5 4875.7 10.3 12.7 4875.5 10.6 12.8 4875.3 10.7 12.9 4875.2 10.9 13.0 4875.2 10.9 4 4885.2 16.0 4886.5 10.1 4876.4 8.8 10.1 4876.4 8.8 11.3 4875.2 10.0 11.6 4875.0 10.3 11.7 4874.8 10.4 11.8 4874.7 10.5 11.9 4874.6 10.6 5 4981.5 33.5 4884.3 12.0 4872.3 9.2 11.9 4872.4 9.1 12.6 4871.7 9.8 12.9 4871.4 10.1 13.0 4871.2 10.2 13.2 4871A 10.4 13.3 4871.0 10.5 7 1 4883.7 49.0 4887.8 11.2 4876.6 7.1 1 11.1 4876.7 1 7.1 12.E 1 4875.2 8.5 1 12.9. 4874.9 1 8.8 13.0 4874.8 1 8.9 13.1 4874.7 9.0 13.2 4874.6 9.2 8 4880.5 28A 4882.8 12.3 4870.6 9.9 12.2 4870.7 9.8 12.9 4869.9 10.6 13.2 4969.6 10.9 13.4 4869.4 11.1 13.6 4869.3 11.2 13.6 4869.2 11.3 9 4873.4 24.5 4875.4 9.6 4865.9 7.5 9.4 4866.0 7.4 9.6 4865.8 7.6 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 10 4870.6 38.0 4873.7 9.6 4864.2 6.4 9.4 4864.3 6.3 9.6 4864.1 6.5 10.0 4863.8 6.8 10.1 4863.6 7.0 10.4 4863.4 7.2 10.4 4863.3 7.2 11 4877.6 26.0 4879.8 11.5 4868.3. 9.3. 11.2 4868.6 9.0 11.8 4868.0 9.6 12.2 4867.6 10.0 12.4 4867.5 10.2 12.6 4867.2 10.4 12.6 4867.2 10.4 12 4880.7 27.0 4882.9 8.4 4874.6 6.1 8.3 4874.7 6.0 9.7 4873.2 7.4 10.2 4872.7 7.9 10.3 4872.6 8.1 10.4 4872.5 8.1 10.5 4872.4 8.2 13 4882.2 30.5 4884.8 75 4877.3 4.9 7.3 4877.5 4.8 8.8 4876.0 6.3 9.2 4875.5 6.7 9.4 4875.4 6.8 9.4 4875.3 6.9 9.6 4875.2 7.1 14 4917.4 13.5 4918.5 17.6 4900.9 16.4 17.4 4901.1 16.3 17.4 4901.1 16.2.. 17.5 4901.0 16.3 17.6 4900.9 16.5 17.7 4900.8 16.5 17.7 4900.8 16.6 15 4906.9 40.0 4910.2 9.2 4901.0 5.9 9.0 4901.2 5.7 9.0 4901.2 5.7 9.0 4901.2 5.7 9.1 4901.1 5.7 9.1 4901.1 5.7 9.1 4901.1 5.7 16 4880.0 22.0 4881.8 6.8 4875.0 5:0 6.6 4875.2 4.8 8.4 4873.4 6.6 9.1 4872.7 7.3 1 9.2 4872.7 73 9.1 4872.8 7.2 9.2 4872.6 7.4 17 4877.5 1.5 4877.7 8.5 4869.2 8.4 8.4 4869.3 8.2 9.2 4868.5 9.1 9.5 4868.1 9.4 9.5 4868.1 9.4 9.5 4868.2 9.3 9.6 4868.1 9.5 18 4868.8 24.0 4870.8 9.0 4861.9 6.9 8.8 4862.1 6.8 9.0 4861.8 7.0 9.3 4861.5 7.3 9.2 4861.6 7.2 93 4861.5 7.3 9.5 4861.3 7.5 19 1 4876.3 13.1 1 4877.4 9.6 1 4867.9 8.5 1 9.5 4868.0 1 8.4 9.6 1 4867.8 8.5 1 9.8 4867.7 8.7 10.0 4867.4 1 8.9 10.3 4867.1 1 9.2 10.3 1 4867.1 9.2 20 4877.3 11.8 4878.3 6.8 4871.5 5.8 6.7 4871.6 5.8 6.8 4871.5 5.8 7.1 4871.3 6.1 7.4 4870A 6.4 7.8 4870.5 6.9 7.9 4870.4 6.9 21 4882.3 12.8 4883.3 9.9 4873.4 8.8 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 22 4872.7 13.3 4873.8 43 4869.5 3.2 4.2 4869.6 3A 4.3 4869.5 3.2 4.3 4869.5 3.2 4.5 4869.4 3.3 4.6 4869.2 3.5 4.6 4869.2 3.5 23 4876.4 179 4877.9 6.8 4871.1 5.3 6.7 4871.2 5.2 6.7 4871.2 5.2 6.7 4871.2 5.3 6.8 4871.1 5.3 6.6 4871.3 5A 6.6 4871.3 5.1 24 4880.3 37.9 4883.5 10.2 4873.3 7.0 10.2 4873.3 7.0 10.2 4873.2 7.1 10.2 4873.2 7.1 10.3 4873.2 7.1 10.2 4873-2 7.1 10.2 4873.2 7.1 25 4874.2 17.6 4875.7 5.9 4869.8 4.4 5.8 4869.9 4.3 5.9 4869.8 4.4 6.0 4869.7 4.5 6.1 4869.6 4.6 6.2 4869.5 4.7 6.2 4869.5 4.7 26 4873.4 38.9 4876.7 7.9 4868.8 4.6 7.8 4868.8 4.6 7.9 4868.8 4.6 7.9 4868.8 4.7 8.1 4868.6 4.8 8.1 4868.6 4.8 8.1 4868.5 4.9 BH 1 4874.2 14.6 4875.4 5.4 4870.0 4.2 5.3 4870.1 4.1 5.4 1 4870.0 4.2 5.5 4869.9 4.3 5.6 4869.8 4.4 5.8 4869.6 4.5 5.8 4869.6 4.5 BH 2 4879.6 17.3 4881.0 8.0 4873.0 6.5 8.0 4873.0 6.6 8.0 4873.0 6.6 8.0 4873.0 6.5 8.1 4872.9 6.6 8.3 4872.7 6.9 83 4872.7 6.9 BH 3 4877.5 33.0 4880.2 71 4873.2 4.3 7.0 4873.2 4.3 7.3 4873.0 4.5 7.4 4872.8 43 7.4 4872.9 4.6 7.3 4873.0 4:5 7A 4872.9 4.6 SH 4 4873.4 16.6 4874.8 5.1 4869.7 3.7 5.0 4869.8 3.6 S.1 4869.7 3.7 S. 4869.6 3.8 5.3 4869.5 3.9 5.3 4.69.4 3.9 5.3 4869.4 3.9 8H 5 1 4873.E 1 2.9 1 4874.1 1 4.5 1 4869.E 1 4.2 1 4.4 1 4869.7 1 4.1 1 4.5 4869.E 1 4.2 4.5 1 4869.5 1 4.3 1 4.6 1 4869.5 1 4.3 1 4.6 4869.5 4.4 1 4.7 1 4869.3 1 4.5 FCRID Water Surface Elevations 2023 DATA June 15,2023 August 2,2023 August 15,2023 September 17,2023 October 25,2023 December 1,2023 December 20,2023 Top of Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Ditch Water Distance to Distance to Distance to Distance to Distance[o Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Wall/Pipe Surface Surface Surface Surface Surface Surface Surface Location Elevation(ft,Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surfa<e Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (k,NAVD88) ('in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) Headwall DS Side Environmental Dr 4884.80 78 6.5 4878.3 80 8:7 4878.1 96 8.0 4876.8 94 7.8 4877.0 98 8.1 4876.7 102 8.5 4876.3 105 8.8 4876.1 Northeast Wingwall 4885.90 102 8.5 4877.4 104 8.7 4877.2 122 10.2 4875.7 124 10.3 4875.6 124 10.3 4875.6 125 10.4 4875.5 128 10.7 4875.2 at William Neal Parkway Southeast Wingwall at William Neal Parkway 4885.79 100 8i3: 4877.5 302 8.5. 4877.3 121 30.0 4875.7 322 10.1 4875.7 122 30.2 4875.E 123 10.2 4875:6 126 30.5 4875.3 Northeast Wingwall at Radial Gate Upstream 4881.10 53 4.4 4876.7 50 4.1 4877.0 79 6.6 4874.5 82 6.8 4874.3 83 6.9 4874.2. 82 6.8 4874.3 86 7.1 4874.0 of Horsetooth Road Boxelder Water Surface Elevations 2023 DATA June 15,2023 August 2,2023 August 15,2023 September 17,2023 October 15,2023 December 1,2023 December 15,2023 Top of Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Distance to Distance to Ditch Water Location Wall/Pipe Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Water Surface Water Surface Surface Elevation(ft, (in) Ikl Elevation (in) (ft) Elevation (in) 1R1 Elevation (in) (ft) Elevation (in) (S Elevation (in) (ft) Elevation (in) Iftl Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Wingwall SE Side Siphon Outlet 4877.65 27.0 2.3. 4875.4 26.5 2.2 4875.4 27.5 2.3 4875.4 293 2A 4875.2 32.5 2.7 4874.9 37.5 3A 4874.5 37.0 3.1 4874.6 Top of CMP-Upstream 4871.61 25.8 2.1 4869.5 24.0 2.0 4869.6 24.5 2.0 4869.6 263 2.2 4869.4 31.5 2.6 4869.0 36.8 3.1 4868.5 36.0 3.0 4868.6 (Southern Crossing) Top of CMP-Downstream (Southern Crossing) 4871.77 30.5 2.5 4869.2 30.0 2.5 4869.3 29.5 2.5 4869.3 30.5 2.5 4869.2 34.8 2.9 4868.9 40.0 3.3 4868.4 39.8 3.3 4868.5 Northwest Corner of Wingwall Upstream of Drop Structure 4865.45 24.5 2.0 4863.4 24.5 2.0 4863.4 41.5 3.5 4862.0 25.5 2.1 4863.3 29.5 2.5 4863.0 34.0 2.8 4862.6 34.0 2.8 4862.6 Southeast Corner of Wingwall 4865.18 41.0 3.4 4861.8 42.0 3.5 4861.7 24.5 2.0 4863.1 39.5 3.3 4861.9 46.5 3.9 4861.3 51.5 4.3 4860.9 '51.5 4.3 4860.9 Downstream of Drop Structure Western Wall at Check Structure 4864.14 36.5 3.0 4.61A 35.5 3.0 4861.2 35.0 2.9 4861.2 36.5 3.0 4861.1 40.0 3.3 4860.8 423 39 4160.E 42.0 3:5 4860.6 Adjacent to Rigden Reservoir Pond Water Surface Elevations 2023 DATA June 15,2023 July 15,2023 August 15,2023 September 17,2023 October 25,2023 November 15,2023 December 15,2023 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Pond Surface Pond Surface Pane Surface Pond Surface Pane Surface Pond Surface Pan.Surface Stall Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Location Elevation Elevation Elevation Elevation Elevation Elevation Elevation Elevation(k, Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage NAVD88) (ft) (ft Ift,NAVD88) (ft (ft) (k,NAVD88) ft (ft) (k,NAVD88) (ft) (ft) (k,NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (k,NAVD88) (ft) (ft) (k,NAVD88) Staff Gage Located on South Bank Near Center of Pond 4876.Z9 2.2 1.8 4874.5 2.2 1.8 4674.5 2.2 1.8 4874.5 2.1 1.9 4874.4 2.0 2.0 4874.3 21 1.9 4874.4 2.1 1.9 4874.4 Page 2 of 3 TABLE A.4.2:STRAUSS LAKE DEVELOPMENT GROUNDWATER WELL READINGS FOR PHASE 2 Monitoring Well Data 2024 DATA STATISTICS January 31,2024 February 15,2024 March 27,2024 April 22,2024 Depth from Distance to Depth to Distance to Depth to Distance to Depth to Distance to Depth to Maximum Average Minimum Average Depth to Ground Top of Well Groundwater Groundwater Groundwater Groundwater Monitoring top of Well to Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater from Elevation Elevation(k, Elevation Elevation Elevation Elevation Well ft Ground from Top of from Ground from Top of from Ground from lop of from Ground from Top of from Ground Surface Elevation Surface Elevation Surface Elevation Ground Surface (ft,NAVD88) Inches NAVD88) Well ft) (h,NAVD88) Surtace(ft Well ft (k,NAVD88) Surface(ft) Well(ft) (ft,NAVD88) Surface(ft Well ft (ft,NAVD88) Surface(ft) (ft,NAVD88 ft,NAVD88) (ft,NAVD88) (ft) 1 4886.0 25.5 4888.2 13.1 4875.1 10.9 13.0 4875.2 10.9 14.6 4873.5 12.5 14.2 4874.0 12.1 4876.2 4875.2 4873.5 10A 4 4985.2 16.0 4886.5 12.0 4874.6 10.6 11.9 4874.6 10.6 12.0 4874.6 10.6 11.9 4874.7 10.5 4876.4 4874.9 4874.5 10.3 5 4981.5 33.5 4884.3 13.3 4871.0 10.5 13.2 4871.1 10.4 13.4 4870.9 10.6 13.1 4871.2 10.3 4872.4 4871.3 4870.9 10.2 7 4883.7 49.0 1 4887.8 13.3 1 4874.6 92 1 13.1 4874.7 9.0 13.1 4874.8 9.0 1 13.0 4874.8 1 8.9 4876.7 4875.0 4874.6 8.8 8 4880.5 28D 4882.8 13.6 4869.2 11.3 13.6 4869.3 11.2 13.5 4869.3 11.2 13.3 4969.6 10.9 4870.7 4969.5 4869.1 11.0 9 4873.4 24.5 4875.4 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 4866.0 4865.4 4864.9 8.0 10 4870.6 38D 4873.7 10.4 4863.4 7.2 10.4 4863.4 7.2 10.3 4863.4 7.2 9.9 4863.8 6.7 4864.3 4863.6 4863.3 6.9 11 4877.6 26.0 4879.8 12.7 4867.2 10.5 12.6 4867.2 10.5 12.6 4867.3 10.4 12.5 4867.3 10.3 4868.6 4867.4 4867.1 10.2 12 4880.7 27.0 4882.9 10.6 4872.4 8.3 10.5 4872.4 8.2 10.3 4872.6 8.1 10.2 4872.7 8.0 4874.7 4872.7 4872.1 7.9 13 4882.2 30.5 4884.8 9.6 4875.1 7.1 9.6 4875.2 7.0 9.4 4875.4 6.8 9.4 4875.4 6.8 4877.5 4875.5 4874.9 6.7 14 4917.4 13.5 4918.5 17.8 4900.7 16.7 17.8 4900.7 16.7 17.8 4900.7 16.6 17.8 4900.7 16.6 4901.1 4900.4 4999.4 16.9 15 4906.9 40.0 4910.2 9.1 4901.1 5.7 9.1 4901.1 5.7 9.0 4901.2 5.7 1 9.0 4901.2 1 5.7 4901.2 4901.1 4901.0 5.7 16 4880.0 22.0 4881.8 9.3 4872.6 7.4 9.2 4872.6 7.4 9.0 4872.8 7.2 8.9 4873.0 7.0 4875.2 4872.9 4872.0 7.2 17 4877.5 1.5 4877.7 9.6 4868.1 9.4 9.6 4868.1 9.5 9.5 4868.1 9.4 9.4 4868.3 9.3 4869.3 4868.2 4967.8 9.3 18 4868.8 24.0 4870.8 9.5 4861.3 7.5 9.5 4861.3 7.5 9.5 4861.3 7.5 9.3 4861.6 7.3 4862.1 4861.5 4861.3 7.3 19 4876.3 13.1 4877.4 10.3 4867.1 9.2 10.3 4867.1 9.2 10.3 4867.1 9.3 9.9 4867.5 8.8 4868.0 4967.4 4867.1 8.9 20 4877.3 11.8 4878.3 7.9 4870.4 6.9 7.8 4870.5 6.8 8.9 4869.4 7.9 8.1 4870.3 7.1 4871.6 4870.7 4869.4 6.6 21 4882.3 12.8 4883.3 N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A N/A 4873.4 4872.5 4872.1 9.7 22 4872.7 13.3 1 4873.8 4.5 1 4869.3 3.4 4.5 4869.3 1 3A 4.6 1 4869.2 3.5 1 4.3 4869.5 1 3.2 4869.6 4869.3 4969.1 3.4 23 4876.4 179 4877.9 6.5 4871.4 5.0 6.6 4871.3 5.1 6.9 4871.0 5.4 6.6 4871.3 5.1 4871.4 4871.2 4871:0 5.2 24 4880.3 37.9 4883.5 10.2 4873.2 7.1 10.3 4873.2 7.1 10.3 4973.2 7.1 10.2 4873.3 7.0 4873.3 4873.2 4873.1 7.1 25 4874.2 17.6 4875.7 6.2' 4869.5 4.7 6.2 4869.5 4.7 6.2 4869.4 4.8 6.0 4869.6 4.6 4869.9 4869.6 4869.4 4.6 26 4873.4 38.9 4876.7 8.1 4868.6 4.8 8.2 4868.5 4.9 8.1 4868.6 4.9 7.9 4868.8 4.6 4868.8 4868.7 4868.5 4.8 BH 1 4874.2 14.6 4875.4 5.8 4869.6 4.5 5.7 4869.7 4.5 5.9 4869.5 4.7 5.6 4869.8 4.4 4870.1 4869.7 4869.5 4.4 BH 2 4879.6 17.3 4881.0 8.3 4872.7 6.9 8.3 4872.7 6.9 8.4 4872.6 6.9 8.0 4873.0 6.6 4873.0 4872.9 4872.6 6.7 BH 3 4877.5 33.0 4880.2 74 4872.9 4.6 7.4 4872.8 4.7 7.4 4872.9 4.6 7.3 4873.0 4.5 4873. 1 4872.9 4872.6 4.6 SH 4 4873.4 16.6 4874.8 5.3 4869.4 3.9 5.3 4869.5 3.9 5.4 4869.4 4.0 5.2 4869.5 3.8 4869.8 4969.5 4869.4 3.9 BH 5 4873.E 2.9 4874.1 4.7 4869.4 4.4 4.7 4869.4 4.4 4.7 4869.3 4.5 4.6 4869.5 4.3 4869.7 4869.5 1 4869.3 1 4.4 FCRID Water Surface Elevations 2024 DATA STATISTICS January 15,2024 February 15,2024 March 27,2024 April 22,2024 Top of Ditch Water Ditch Water Ditch Water Ditch Water Maximum Ditch Average Ditch Minimum Ditch Distance to Distance to Distance to Distance to Distance to Distance to Distance to Distance to Wall/Pipe Surface Surface Surface Surface Water Surface Water Surface Water Surface Location Elevation(ft,Water Surface Water Surface Elevation Water Surface Water Surtace Elevation Water Surface Water Surface Elevation Water Surface Water Surface Elevation Elevation Elevation Elevation NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (h,NAVD88) (in) (ft) (ft,NAVD88) (in) (ft) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) Headwall DS Side Environmental Dr 4884.80 103 8.6. 4876.2 102 8.5. 4876.3 101 8.4 4876.4 99 8.3 4876.6 4878.3 4876.7 4876.1 Northeast Wingwall 4885.90 126 10.5. 4875.4 125 10.4 4875.5 124 10.3 4875.6 125 10.4 4875.5 4877.4 4875.7 4875.2 at William Neal Parkway Southeast Wingwall 4885.79 124 10.3 487S.5 123 10.3 4875.5 122 10.2 4875.6 122 10.2 4875.6 4877.5. 4875.8 4875.3 at William Neal Parkway Northeast Wingwall at Radial Gate Upstream 4881.10 84 7.0 4874.1 82 6.8` 4874.3 81 6.8 4874.4 81 6.8 4874.4 4877.0 4874.E 4874.0 of Horsetooth Road Boxelder Water Surface Elevations 2024 DATA STATISTICS January 15,2024 February 15,2024 March 27,2024 April 22,2024 Top of Pipe Ditch Water Ditch Water Ditch Water Ditch Water Maximum Ditch Average Ditch Minimum DitchDistanceac Distance Surface Distance Water Distance to Distance to Distance to Surface Surface Distance to Distance to Walla Surface Water surface Water Surface Water Surface Location Water Surface Water Surface Surface Surface Water Surface Water Surface Water Surface Water Surface Water Surface Elevation(k, (in) Iftl Elevation (in) (ft) Elevation (in) AElevation (in) (k) Elevation Elevation Elevation Elevation NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88) (ft,NAVD88 ft.NA1088 ft,NAVD88 Wingwall SE Side Siphon Outlet 4877.65 37.5 3A 4874.5 37.5 3.1 4874.5 37.0 3.1 4874.6 31.0 2.6 4875.1 4875.4 4974.8 4874.4 Top of CMP-Upstream 4871.61 36.3 3.0 4868.6 36.0 3.0 4868.6 N/A N/A N/A N/A N/A N/A 4869.6 4868.9 4868.3 (Southern Crossing) Top of CMP Downstream (Southern Crossing) 4871.77 39,5 3.3. 4868.5 39.5 3.3. 4868.5 39.5 3.3 4868.5 33.0 2.8 4969.0 4869.3 4868.7 4868.2 Northwest Corner of Wingwall Upstream of Drop Structure 4865.45 34.3 2.9 4862.6 33.5 2.8 4862.7 33.5 2.8 4862.7 26.0 2.2 4863.3 4863.5 4862.9 4862.0 Southeast rof Wingwall uctur Downstreamm of Drop Structure 4865.18 52.5 4.4 4860.8 52.0 4.3 4860.8 53.0 4.4 4860.8 47.0 3.9 4861.3 4863.1 4861.2 4860.8 of Western Wall at Check Structure Adjacent to Rigden Reservoir 4864,14 42.5 3.5 4860.6 42.5 3.5 4860.6 42.5 3.5 4860.6 39.0 3.3 4860.9 4861.2 4860.8 4860.6 Pond Water Surface Elevations 2024 DATA STATISTICS January 15,2024 February 15,2024 March 27,2024 April 22,2024 4.0'Mark on Water Surface Distance to Water Surface Distance to Water Surface Distance to Water Surface Distance to Maximum Pond Average Pond Minimum Pond Surface Pond Surface Pond Surface Pond Surface Stall Gage Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Reading on 4.0'Mark on Water Surface Water Surface Pond Water Location Elevation Elevation Elevation Elevation(k, Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Staff Gage Elevation Elevation Surface Elevation NAVD88) (ft) (ft) (ft,NAVD88) (ft) (ft) (ft,NAVD88) 11 (ft) (ft,NAVD88) (ft) (k) (Elevation ft,NAVD88) ft,NAVD88 aft,NAVD88 (ft,NAVD88) Staff Gage Located on South Bank Near Center N/A N/A N/A N/A N/A N/A of Pond 4876.29 2.6 1.4 4874.9 2.6 1.4 4874.9 (Pond (Pond (Pond jPond (Pond (Pond 4874.9 4874.5 4874.2 Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Dewatered) Page 3 of 3 APPENDIX B. GROUNDWATER MONITORING RESULTS APPENDIX B.I. GROUNDWATER ELEVATION SURFACE MAPS P: COCLFIO_STRAUSS LAKE DEVELOPMENT GROUNDWATER MONITORING ACAD MAXIMUM GROUNDWATER SURFACE PHASES COMBINED.DWG 32 X4878.30 IDS ENVRIONMENTAL DRIVE I , Ire II L II\ � 4870 SIP 24 �\0°®4873.30 MW 24 29 14873.20 28\ jII 13b6473— Bill3 4: IBH 2 \ ,�k` ♦R� �� � �r III \ 1 � 31 �;•.\ .ti ff -' 1 ; 1 11 .fir 4869.90 X 4869.70 I � 23,/ MW 25 23 BH 5 \ r `j - I \ 4tS7 f A � i \ \ \�MW 23 26 Xaa69.s0\� 4868.80 � „ }� f`\\vim••- �, '�i \\ \ \\ \\ BH MW 26 2 EXISTING UNDERDRAIN 0 SYSTEM �• �` 11 1\ \ \ B 1 log11 \\ \\\\ 2 4869.60 Fu \ MW 22 37 4871.00 F'9 j- I I \\\ US CULVERT 1 38 —WIVArs \ 4-870.70 44 / rip, 4 CULVERT 1 PX ! vAv OND1 QAA,,\\\ 2 ,V 4870.90 A 4 —=�I j IFFY MW 2 39 (2'9 876.2 I F_ I \JJJ, 4870.00 Y mw 1 I i 1 20 US CULVERT 2 I c WILLIAM NEAL PKWY , 77.u1 NEA4 II MW120 4869.90 WS & % DS CULVERT 2 3 i I 34?' 4870.00 MW 3 I 4877.60 I 21 I � _ I DS�LLIAM NEAL I ®4073.40 I MIN 21 1 i GROUNDWATER fSURFACE BORDER I ti. I I I I I I 19 1 I I I I I I I 4868.00 MW 19 7 �+ Swc ®4676.50 I j g ttI ll ` t�M 4868:50 Mw a I I ©46 2.60 I 1 MW H O MP 5 �111 II ii it 111 111 `O�'A RIGDEN RESERVOIR Lu LL P,y PERCHERON ROAD Lu II it s 11 111 11 1@4881 70 (\ \ \ r 48 89 11 11 01 4867.00/ \ \ \ 1 I I I MW 9 \ \ I 1 \ \ 1 I I I \\ \\ \ \ t 13 ®4877.50 \ \ 1 1 1 q I I <MW 13 \\ \\ \\ 11 1 1 I ®486$.60 I 10 121 1 1 / MW,1 © 0 41 MW 10 4gy 74.70/ / / / I I MW 10 4863.70 M 12 US DROP I I 42 �4863.10 \ ♦\\\ \\\\ \\ \ \ I / / ll DS DROP 1. qq J Oil 1111 I I11 18 43 ✓ // //// // 11i �}8,720 \\ \\ i / / 4862.10 X4862.70 MW170 OMW 18 RIGDEN CHECK 4877.20 MW 14 RADIAL GATE IWIFa HORSETOOTH ROAD ,I / NOTES: THIS DRAWING IS BASED ON COLORADO STATE PLANE NORTH COORDINATE N SYSTEM. ALL ELEVATIONS SHOWN HERON ARE IN THE NORTH AMERICAN VERTICAL DATUM 1988 (NAVD88) GRAPHICAL SCALE IN FT: 2023 AERIAL PHOTOGRAPH OBTAINED FROM NATIONAL AGRICULTURE IMAGERY PROGRAM (NAIP) 0 125 250 500 n O EA z 0 a x z Z C) m m Z - a . . MAXIMUM GROUNDWATER "mom STRAUSSLAKE o O n W m ro a WELL ELEVATIONS AND ;\„�Ic�-s�>��c<�„s��Iri�� L�,g;,,cer5,Inc DEVELOPMENT c Civil•YVater Resources•Environmental •• N 1 375 B: H .1ooni ore Road,Building 5.—Conine.CO 80525 m m m m SURFACE Pdaae(97o)226-01201Fa(0701226.,1121 ,� y to y www.acewaror.com P: COCLF10-STRAUSS LAKE DEVELOPMENT GROUNDWATER MONITORING ACAD AVERAGE GROUNDWATER SURFACE PHASES COMBINED.DWG 32 X4876.70 DS ENVRIONMENTAL DRIVE n I <, 4874.80 SIPONey�' 24 1 4873.20 -4873 24 29 /28 XBH73.90 \ I 1/ 6(4872.80 \ \\� BH 2 pe\ l \\\ 11 _ 1,p��y,� �s` tiff i i /�V6 31 > I I X 4869.50 qy 0� 4869.60 BH 5 p,J6 Ilk `i k - 1 \ ®T4871.20 MW 25 f A � J i' ,X r \\ 1�W 23 26 30 ;S�s y I \ \ X4469.50 4868.70 MW 26 2 I EXISTING UNDERDRAIN 486 0 SYSTEM \ \ H 1 y I \ \ 2 ©4869.30 \ MW 22 37 4870.20 F�9 j- 1 US CULVERT 1 3844 *70.00 ' X4873.30 \\ \ 31)gii CULVERT 1 ` A, �' • '� a �- h.,a \ POND 1 \\ \ p '✓ 14, y �4 70.70 39 '9Y - �.1 ©•4&T4'40 j 1 1 M 20 4869.00 1 „�''91'le :b MV�I 1 1 1 I US CULVERT 2 WILLIAM NEAL PKWY 48 70 NIL 0 40 -�Ivit ' 4868.90 DS CULVERT 2 i 3 34 wI �4869.20 4875.80 21I MW 3 DS WILLIAM NEAL Iq�g�72.50 Im 21 GROUNDWATER -�-� I I SURFACE BORDER ,µ l 41.�'_,��:e\C v�♦ �y� II I i i I gg9 - 19 4867.40 MW 19 I I I I 6 4874.90 1 1 5 \ OM 4867.70 MW 41 I I ��671.30 MW 6 O �1 \ tea. II I I µ W 5 I I I f i i i I11 II �` - �I 0 i I RIGDEN RESERVOIR J LL � I I I y PERCHERON ROAD w_ s I I I I N 7 I I 6 s 4875.00 I 1 1 ©4869,.60 I I �M 4865.90 MW 7 1 1 1 1 MW 8 1 I MW 9 1 1 1 I I I 13 Q4875.50 1 1 I I - ,rxw 13 1 1 II I ®48671.60 Q4863.90 41 121 MW�1111 1 MW 10 4863.00 ®M 20 / I ! 1 1 q US DROP \ \\\\ \\\\r \ \ Y# 42 4861.50 DS DROP e \\\mo\\\\ \\\1 \\ \\ / / Icz / / / �.'��•� ,'�,�. IX `1s\l I I j IIII I I j� IIII I\\ \\\\\\\\ I/ I / / / / / '': IIII I I IIII 1 �66 1 \ \ 43 1�4a72.60\ \ \ l 17 / / / 18 X4861.10 16\ \ \ \ ,04868.10 QM 4861.50 RIGDEN CHECK MW 17 MW 18 \35 MW 14 -- - X RADIALD RADIAL GATE HORSETOOTH ROAD �mom.nw .I / NOTES: THIS DRAWING IS BASED ON COLORADO STATE PLANE NORTH COORDINATE N SYSTEM. ALL ELEVATIONS SHOWN HERON ARE IN THE NORTH AMERICAN VERTICAL DATUM 1988 (NAVD88) GRAPHICAL SCALE IN FT: 2023 AERIAL PHOTOGRAPH OBTAINED FROM NATIONAL AGRICULTURE IMAGERY PROGRAM (NAIP) 0 125 250 500 0 O = tmn z 0 a x Z C) m m Z o o a AVERAGE GROUNDWATER Om m ` STRAUSSLAKE 0 0 n < j W m N a WELL ELEVATIONS AND \„Il-T>nConsourm- nvimnrs,lnc ^� o DEVELOPMENT �,,,,.avarerneto,es.Envi.onmenrar N ; 1 375 B: H ,1ooni ore Road,Building 5.-Conine.CO 80525 m m m m SURFACE Phaae9,o,22-0120,Fax90,22fi-I,21 ,� y y y www.acewaror.com P: COCLF10_STRAUSS LAKE DEVELOPMENT GROUNDWATER MONITORING ACAD MINIMUM GROUNDWATER SURFACE PHASES COMBINED.DWG 32 X4876.10 ,DS ENVRIONMENTAL DRIVE I I I 4 36 �. X 487r,4..40 SIP0 24 04873.10 y s y �By- 24 29 4872.60 28 X4872.60 \ BH 2 •s tiY�f \ 1 ���� �` 31 25 X4869.30 t 2� ®4869.40 BH 5 *p+," ' + 'Za (04871.0 MW 25 ' f A�1►�`� J, 1 1 N \MW 2 30 26 X 69.40 / 4868.50 '. 4\ ��e\vim,•- � /// \ \ BH A MW 2s a•, , try I \\ 2 1 EXISSYS TING UNDERDRAIN X486BH 1 0 1 2 ©4869.10 III \ MW 22 37 37 4869.40 ry T/w 1 1 US CULVERT 1 38 44 4869.40 al ► cs (\ \IXPOND80 DS CULVERT 1 2 V MW 250 Iv Y r 4869.40 39 '9 MW 1.80 MW 20 J 4868.30 1 MW 1 ,\ US CULVERT 2 WILLIAM NEAL PKWY 1 1 4875.20 X 40 _ I I US WILL" NEAL � X4868.20 DS CULVERT 2 i I 134 �\ 1 Q7 4868.60 I 4875.20 21 1 MW 3 ¢S WILLIAM NEAL \$4872 J Y a ♦n - I MW 21 GROUNDWATER 1 1 ( I m f SURFACE BORDER 194867.10 1 M 1 I 1 I I I Mw 19 �I, 6 ®4874.10/ / 5 ( \ 4867.10 1 �` • �� it't1l- IIMW 4 i 1 MQ48 .50 i i OMW 6 Q I I I I 1 Q RIGDEN RESERVOIR J LL PERCHERON ROAD Lu N ®4674.40 I I A�1 4869.10 I M 4864.90 MW 7 11 1 1 IMW 8 I I MW 9 \ # 1 I I I I 4874..80 \\ 1\ I 11 1 11 1 m 1 �4867.10 I I MW 11 I I I ©14p 6330 41 y12 48 6200(P4872.ip .M 10 �US DROPvmw 1; 42 4860.80 IDS DROP 17 18\ 43 X4860.60 64867.80 ©4861.30 RIGDEN CHECK //C \�������\.\� \ \ \., MW 17 MW 18 MW 14 RADIAL GATE HORSETOOTH ROAD ,I W. / e. NOTES: THIS DRAWING IS BASED ON COLORADO STATE PLANE NORTH COORDINATE N SYSTEM. ALL ELEVATIONS SHOWN HERON ARE IN THE NORTH AMERICAN VERTICAL DATUM 1988 (NAVD88) GRAPHICAL SCALE IN FT: 2023 AERIAL PHOTOGRAPH OBTAINED FROM NATIONAL AGRICULTURE IMAGERY PROGRAM (NAIP) 0 125 250 500 n O = EA z 0 n a x z f m m Z o a G MINIMUM GROUNDWATER "mom ` STRAUSSLAKE o O n W m ro a Inc WELL ELEVATIONS AND ;\„�1l-�TVaterou esourm-ng Envimnmers,tal w DEVELOPMENT �,,,,.avarerneto,es.Envi.onmenrar N ; 1 375 L: H .1ooni ore Road,Building 5.-Conine.CO 80525 m Till SURFACE Phaae9]o,226.0120,Fax90,22fi.1,21 www.acewaror.com APPENDIX B.2. GROUNDWATER ELEVATION PLOTS FCRID Water Surface Elevation at Radial Gate Compared to Monitoring Well #17 Groundwater Elevations 4878.0 4876.0 4874.0 00 0 a z 4872.0 c 0 v w 4870.0 4868.0 4866.0 8/1/2018 1/28/2019 7/27/2019 1/23/2020 7/21/2020 1/17/2021 7/16/2021 Date — —FCRID WSEL at Radial Gate --*--Monitoring Well#17 Boxelder Ditch Water Surface Elevations at Upstream Side of Drop Structure Compared to Monitoring Well #10 Groundwater Elevations 4865.0 4864.5 4864.0 00 0 a z 4863.5 c 0 v w 4863.0 4862.5 4862.0 8/1/2018 1/28/2019 7/27/2019 1/23/2020 7/21/2020 1/17/2021 7/16/2021 Date —�—Boxleder Ditch at US Side of Drop Monitoring Well#10 APPENDIX C. DIGITAL DATA ANdERSON CONSULTING ENC�iNEERS, INC. Civil • Water Resources • Environmental