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HomeMy WebLinkAboutAFFORDABLE SELF STORAGE - FDP180020 - SUBMITTAL DOCUMENTS - ROUND 2 - GEOTECHNICAL (SOILS) REPORTGeotechnical Engineering Report BETCO Self-Storage Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado August 25, 2016 Terracon Project No. 20165074 Prepared for: Hauser Architects PC Loveland, Colorado Prepared by: Terracon Consultants, Inc. Fort Collins, Colorado TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................ i 1.0 INTRODUCTION .............................................................................................................1 2.0 PROJECT INFORMATION .............................................................................................1 2.1 Project Description ...............................................................................................1 2.2 Site Location and Description...............................................................................2 3.0 SUBSURFACE CONDITIONS ........................................................................................2 3.1 Typical Subsurface Profile ...................................................................................2 3.2 Laboratory Testing ...............................................................................................3 3.3 Corrosion Protection (Water-Soluble Sulfates) .....................................................3 3.4 Groundwater ........................................................................................................3 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ......................................4 4.1 Geotechnical Considerations ...............................................................................4 4.1.1 Potentially Unstable Clay Subgrade Soils .................................................4 4.1.2 Shallow Groundwater ...............................................................................4 4.1.3 Expansive Soils ........................................................................................4 4.1.4 Foundation Recommendations .................................................................5 4.2 Earthwork.............................................................................................................5 4.2.1 Site Preparation ........................................................................................5 4.2.2 Demolition ................................................................................................5 4.2.3 Excavation ................................................................................................6 4.2.4 Subgrade Preparation ...............................................................................7 4.2.5 Fill Materials and Placement ......................................................................7 4.2.6 Compaction Requirements ........................................................................8 4.2.7 Utility Trench Backfill ................................................................................8 4.2.8 Grading and Drainage ...............................................................................9 4.3 Foundations .......................................................................................................10 4.3.1 Spread Footings - Design Recommendations .........................................10 4.3.2 Spread Footings - Construction Considerations ......................................11 4.3.3 Drilled Piers Bottomed in Bedrock - Design Recommendations ..............11 4.3.4 Drilled Piers Bottomed in Bedrock - Construction Considerations ...........12 4.4 Seismic Considerations......................................................................................13 4.5 Floor Systems ....................................................................................................13 4.6 Elevator Pit ........................................................................................................13 4.6.1 Elevator Pit Design Recommendations ...................................................14 4.6.2 Elevator Pit Design Recommendations ...................................................14 4.7 Lateral Earth Pressures .....................................................................................15 4.8 Pavements .........................................................................................................16 4.8.1 Pavements – Subgrade Preparation .......................................................16 4.8.2 Pavements – Design Recommendations ................................................17 4.8.3 Pavements – Construction Considerations .............................................19 4.8.4 Pavements – Maintenance .....................................................................19 5.0 GENERAL COMMENTS ...............................................................................................20 TABLE OF CONTENTS (continued) Appendix A – FIELD EXPLORATION Exhibit A-1 Site Location Map Exhibit A-2 Exploration Plan Exhibit A-3 Field Exploration Description Exhibits A-4 to A-10 Boring Logs Appendix B – LABORATORY TESTING Exhibit B-1 Laboratory Testing Description Exhibit B-2 Atterberg Limits Test Results Exhibit B-3 Grain-size Distribution Test Results Exhibits B-4 and B-5 Swell-consolidation Test Results Exhibits B-6 and B-7 Unconfined Compression Test Results Exhibit B-8 Water-soluble Sulfate Test Results Appendix C – SUPPORTING DOCUMENTS Exhibit C-1 General Notes Exhibit C-2 Unified Soil Classification System Exhibit C-3 Description of Rock Properties Exhibit C-4 Laboratory Test Significance and Purpose Exhibits C-5 and C-6 Report Terminology Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable i EXECUTIVE SUMMARY A geotechnical investigation has been performed for the proposed BETCO Self-Storage Facility to be constructed northeast of Conifer Street and Red Cedar Circle in Fort Collins, Colorado. Seven (7) borings, presented as Exhibits A-4 through A-10 and designated as Boring No. 1 through Boring No. 7, were performed to depths of approximately 15.5 to 34.4 feet below existing site grades. This report specifically addresses the recommendations for the proposed BETCO Self-Storage structures, foundations, associated driving and parking areas and earthwork. Detailed recommendations for the design of storm water retention features and the pond are outside our scope of work. Borings performed in these areas are for informational purposes and will be utilized by others. Based on the information obtained from our subsurface exploration, the site can be developed for the proposed project. However, the following geotechnical considerations were identified and will need to be considered:  In general, subsurface condition consisted of approximately 4½ to 9 feet of lean clay with varying amounts of silt and sand over about 12½ to 16½ feet of poorly graded sand with gravel. Sandstone bedrock was encountered below the poorly graded sand and extended to maximum depths explored of about 35 feet.  We recommend the proposed self-storage buildings be constructed on shallow spread footing foundation systems provided the soils below the proposed footings are over- excavated to a depth of 2 feet and replaced with moisture conditioned, properly compacted engineered fill. On-site soils are suitable for reuse as over-excavation backfill below proposed buildings.  As an alternative, the proposed buildings may be constructed on a drilled pier foundation system bottomed in bedrock  A slab-on-grade floor system is recommended for the proposed buildings provided the soils below the floor are over-excavated to a depth of 12 inches and replaced with moisture conditioned, properly compacted engineered fill. On-site soils are suitable for reuse as over- excavation backfill below proposed buildings.  The minimum pavement section for the proposed parking area is 4 inches of asphalt underlain by 4 inches of aggregate base course. The minimum pavement section for the drive lanes is 4½ inches of asphalt underlain by 6 inches of aggregate base course. Rigid pavement recommendations are included in the 4.8.2 Pavements – Design Recommendations section of this report.  The amount of movement of foundations, floor slabs, pavements, etc. will be related to the wetting of underlying supporting soils. Therefore, it is imperative the recommendations Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable ii discussed in the 4.2.8 Grading and Drainage section of this report be followed to reduce potential movement.  The 2012 International Building Code, Table 1613.5.2 IBC seismic site classification for this site is D.  Close monitoring of the construction operations discussed herein will be critical in achieving the design subgrade support. We therefore recommend that Terracon be retained to monitor this portion of the work. This summary should be used in conjunction with the entire report for design purposes. It should be recognized that details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein. The section titled GENERAL COMMENTS should be read for an understanding of the report limitations. Responsive ■ Resourceful ■ Reliable 1 GEOTECHNICAL ENGINEERING REPORT BETCO Self-Storage Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado Terracon Project No. 20165074 August 25, 2016 1.0 INTRODUCTION This report presents the results of our geotechnical engineering services performed for the proposed BETCO Self-Storage Facility to be located northeast of the intersection of Conifer Street and Red Cedar Circle in Fort Collins, Colorado (Exhibit A-1). The purpose of these services is to provide information and geotechnical engineering recommendations relative to:  subsurface soil and bedrock conditions  foundation design and construction  groundwater conditions  floor slab design and construction  grading and drainage  pavement construction  lateral earth pressures  earthwork  seismic considerations Our geotechnical engineering scope of work for this project included the initial site visit, the advancement of seven (7) test borings to depths ranging from approximately 15.5 to 34.4 feet below existing site grades, laboratory testing for soil engineering properties and engineering analyses to provide foundation, floor system and pavement design and construction recommendations. Logs of the borings along with an Exploration Plan (Exhibit A-2) are included in Appendix A. The results of the laboratory testing performed on soil and bedrock samples obtained from the site during the field exploration are included in Appendix B. 2.0 PROJECT INFORMATION 2.1 Project Description Item Description Site layout Refer to the Exploration Plan (Exhibit A-2 in Appendix A) Structures The proposed construction includes one two-story climate controlled self-storage facility as well as multiple single-story, self-storage buildings. Paved access drives and parking areas are also planned. A detention pond is planned on the east side of the storage units. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 2 Item Description Below-grade areas No below-grade areas are planned; however, an elevator pit may be used in the two-story climate controlled building. Traffic loading NAPA Traffic Class (assumed): Automobile Parking Areas: Class I Truck traffic and main drives: Class II 2.2 Site Location and Description Item Description Location The project site is located northeast of the intersection of Conifer Street and Red Cedar Circle in Fort Collins, Colorado. Existing site features The north side of the site is currently occupied by a fenced area filled with cars and what appears to be old equipment. The south side of the site is currently undeveloped land. Surrounding developments The site is bordered by Conifer Street to the south and Red Cedar Circle to the west. To the north and east of the site are industrial development lots. Current ground cover The ground in the fenced area is a gravel surface with some native weeds. The ground on the south side of the site is covered with native grasses and weeds. Existing topography The site is relatively flat. 3.0 SUBSURFACE CONDITIONS 3.1 Typical Subsurface Profile Specific conditions encountered at each boring location are indicated on the individual boring logs included in Appendix A. Stratification boundaries on the boring logs represent the approximate location of changes in soil types; in-situ, the transition between materials may be gradual. Based on the results of the borings, subsurface conditions on the project site can be generalized as follows: Material Description Approximate Depth to Bottom of Stratum Consistency/Density/Hardness Lean clay with varying amounts of silt and sand About 4½ to 9 feet below existing site grades. Very soft to very stiff Poorly graded sand with gravel About 19½ to 22 feet below existing site grades. Medium dense to very dense Sandstone bedrock To the maximum depth of exploration of about 34 feet. Very hard Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 3 3.2 Laboratory Testing Representative soil samples were selected for swell-consolidation testing and exhibited no movement to 3½ percent swell when wetted. The sandstone is considered to have low expansive potential or non-expansive. Two samples of lean clay soils exhibited unconfined compressive strengths of approximately 416 and 4,319 pounds per square foot (psf). Samples of site soils selected for plasticity testing exhibited low to moderate plasticity with liquid limits ranging from non-plastic to 38 and plasticity indices ranging from non-plastic to 21. Laboratory test results are presented in Appendix B. 3.3 Corrosion Protection (Water-Soluble Sulfates) Results of water-soluble sulfate testing indicate that ASTM Type V, or modified Type II portland cement should be specified for all project concrete on and below grade. As an alternative, ACI allows the use of cement that conforms to ASTM C150 Type II requirements, if it meets the Type V performance requirements (ASTM C452) of ASTM C150 Table 4. ACI 201 also allows a blend of any type of portland cement and fly ash with an expansion of less than 0.05 percent at 6 months when tested in accordance with ASTM C1012. Foundation concrete should be designed for severe sulfate exposure in accordance with the provisions of the ACI Design Manual, Section 318, Chapter 4. 3.4 Groundwater The boreholes were observed while drilling and after completion for the presence and level of groundwater. In addition, temporary piezometers made of slotted PVC pipe was installed in two of the borings and delayed water levels were also obtained in those borings. The water levels observed in the boreholes are noted on the attached boring logs, and are summarized below Boring Number Depth to groundwater while drilling, ft. Depth to groundwater 11 days after drilling, ft. Elevation of groundwater 11 days after drilling, ft. 1 7 Backfilled after drilling Backfilled after drilling 2 10 Backfilled after drilling Backfilled after drilling 3 9 Backfilled after drilling Backfilled after drilling 4 9 Backfilled after drilling Backfilled after drilling 5 8 Backfilled after drilling Backfilled after drilling 6 9.5 6 93.4 7 9 7.8 90.4 These observations represent groundwater conditions at the time of the field exploration and approximately 11 days later, and may not be indicative of other times or at other locations. Groundwater levels can be expected to fluctuate with varying seasonal and weather conditions, Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 4 and other factors. Groundwater level fluctuations occur due to seasonal variations, amount of rainfall, runoff and other factors not evident at the time the borings were performed. Therefore, groundwater levels during construction or at other times in the life of the structures may be higher or lower than the levels indicated on the boring logs. The possibility of groundwater level fluctuations should be considered when developing the design and construction plans for the project. Fluctuations in groundwater levels can best be determined by implementation of a groundwater monitoring plan. Such a plan would include installation of groundwater piezometers, and periodic measurement of groundwater levels over a longer period of time. 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION 4.1 Geotechnical Considerations Based on subsurface conditions encountered in the borings, the site appears suitable for the proposed construction from a geotechnical point of view provided certain precautions and design and construction recommendations described in this report are followed. We have identified geotechnical conditions that could impact design and construction of the proposed structures, pavements, and other site improvements. 4.1.1 Potentially Unstable Clay Subgrade Soils Based on the soils encountered in our borings, portions of the upper lean clay soils may be at moisture contents that could result in unstable conditions below foundations, exterior concrete flatwork, and pavement. These conditions will likely require corrective work prior to completion of the planned over-excavation below the buildings. Exposure to significant precipitation events, snowmelt or repeated rubber tire traffic could also develop unstable conditions. It is likely that some subgrade areas below the site will require stabilization. 4.1.2 Shallow Groundwater As previously stated, groundwater was measured at depths ranging from about 7 to 10 feet below existing site grades during drilling operations. Terracon recommends maintaining a separation of at least 3 feet between the bottom of proposed below-grade foundations and measured groundwater levels. It is also possible and likely that groundwater levels below this site may rise due to rainfall and seasonal variations. 4.1.3 Expansive Soils Laboratory testing indicates the native clay soils exhibited non-expansive to moderate expansive potential at the samples in-situ moisture content. However, it is our opinion the sample that had a higher swell potential also had a much lower moisture content and all on-site materials will exhibit a higher expansive potential if the lean clays undergo a significant loss of moisture. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 5 This report provides recommendations to help mitigate the effects of soil shrinkage and expansion. However, even if these procedures are followed, some movement and cracking in the structures, pavements, and flatwork should be anticipated. The severity of cracking and other damage such as uneven floor slabs will probably increase if any modification of the site results in excessive wetting or drying of the expansive clays. Eliminating the risk of movement and distress is generally not feasible, but it may be possible to further reduce the risk of movement if significantly more expensive measures are used during construction. It is imperative the recommendations described in section 4.2.8 Grading and Drainage of this report be followed to reduce movement. 4.1.4 Foundation Recommendations We recommend the proposed self-storage buildings be constructed on shallow spread footing foundation systems provided the soils below the proposed footings are over-excavated to a depth of 2 feet and replaced with moisture conditioned, properly compacted engineered fill. On-site soils are suitable for reuse as over-excavation backfill below proposed buildings. As an alternative, the proposed buildings may be constructed on a drilled pier foundation system bottomed in bedrock. 4.2 Earthwork The following presents recommendations for site preparation, excavation, subgrade preparation and placement of engineered fills on the project. All earthwork on the project should be observed and evaluated by Terracon on a full-time basis. The evaluation of earthwork should include observation of over-excavation operations, testing of engineered fills, subgrade preparation, subgrade stabilization, and other geotechnical conditions exposed during the construction of the project. 4.2.1 Site Preparation Prior to placing any fill, strip and remove existing vegetation and any other deleterious materials from the proposed construction areas. Stripped organic materials should be wasted from the site or used to re-vegetate landscaped areas or exposed slopes after completion of grading operations. Prior to the placement of fills, the site should be graded to create a relatively level surface to receive fill, and to provide for a relatively uniform thickness of fill beneath proposed structures. If fill is placed in areas of the site where existing slopes are steeper than 5:1 (horizontal:vertical), the area should be benched to reduce the potential for slippage between existing slopes and fills. Benches should be wide enough to accommodate compaction and earth moving equipment, and to allow placement of horizontal lifts of fill. 4.2.2 Demolition Demolition of the existing fence and associated concrete entrance should include complete removal of all foundation systems, below-grade structural elements, pavements, and exterior flat work within the proposed construction area. This should include removal of any utilities to be abandoned along with any loose utility trench backfill or loose backfill found adjacent to existing foundations. All Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 6 materials derived from the demolition of existing structures and pavements should be removed from the site. The types of foundation systems supporting the existing fence are not known. Consideration could be given to re-using the asphalt and concrete provided the materials are processed and uniformly blended with the on-site soils. Asphalt and/or concrete materials should be processed to a maximum size of 2 inches and blended at a ratio of 30 percent asphalt/concrete to 70 percent of on-site soils. 4.2.3 Excavation It is anticipated that excavations for the proposed construction can be accomplished with conventional earthmoving equipment. Excavations into the on-site soils will encounter weak and/or saturated soil conditions with possible caving conditions. The soils to be excavated can vary significantly across the site as their classifications are based solely on the materials encountered in widely-spaced exploratory test borings. The contractor should verify that similar conditions exist throughout the proposed area of excavation. If different subsurface conditions are encountered at the time of construction, the actual conditions should be evaluated to determine any excavation modifications necessary to maintain safe conditions. Although evidence of fills or underground facilities such as septic tanks, vaults, basements, and utilities was not observed during the site reconnaissance, such features could be encountered during construction. If unexpected fills or underground facilities are encountered, such features should be removed and the excavation thoroughly cleaned prior to backfill placement and/or construction. Any over-excavation that extends below the bottom of foundation elevation should extend laterally beyond all edges of the foundations at least 8 inches per foot of over-excavation depth below the foundation base elevation. The over-excavation should be backfilled to the foundation base elevation in accordance with the recommendations presented in this report. Depending upon depth of excavation and seasonal conditions, surface water infiltration and/or groundwater may be encountered in excavations on the site. It is anticipated that pumping from sumps may be utilized to control water within excavations. The subgrade soil conditions should be evaluated during the excavation process and the stability of the soils determined at that time by the contractors’ Competent Person. Slope inclinations flatter than the OSHA maximum values may have to be used. The individual contractor(s) should be made responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom. All excavations should be sloped or shored in the interest of safety following local, and federal regulations, including current OSHA excavation and trench safety standards. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 7 As a safety measure, it is recommended that all vehicles and soil piles be kept a minimum lateral distance from the crest of the slope equal to the slope height. The exposed slope face should be protected against the elements 4.2.4 Subgrade Preparation Due to the variations of density in the upper lean clays, we recommend the top 2 feet of soils below footing foundations and the top 12 inches of soil below floor slabs be over-excavated, moisture conditioned, and recompacted to at least 95 percent of the maximum dry unit weight as determined by ASTM D698 before any new fill or foundation or pavement is placed. In addition, the top 8 inches of the ground surface at the base of the over-excavation and below other improvement planned on the site should be scarified, moisture conditioned, and recompacted to at least 95 percent of the maximum dry unit weight as determined by ASTM D698. The stability of the subgrade may be affected by precipitation, repetitive construction traffic or other factors. If unstable conditions develop, workability may be improved by scarifying and drying. Alternatively, over-excavation of wet zones and replacement with granular materials may be used, or crushed gravel and/or rock can be tracked or “crowded” into the unstable surface soil until a stable working surface is attained. Use of geotextiles could also be considered as a stabilization technique. Lightweight excavation equipment may also be used to reduce subgrade pumping. 4.2.5 Fill Materials and Placement The on-site soils or approved granular and low plasticity cohesive imported materials may be used as fill material. The soil removed from this site that is free of organic or objectionable materials, as defined by a field technician who is qualified in soil material identification and compaction procedures, can be re-used as fill for the building pad and pavement subgrade. It should be noted that lean clay soils may require reworking to adjust the moisture content to meet the compaction criteria. Imported soils (if required) should meet the following material property requirements: Gradation Percent finer by weight (ASTM C136) 4” 100 3” 70-100 No. 4 Sieve 50-100 No. 200 Sieve 15-60 Soil Properties Values Liquid Limit 35 (max.) Plastic Limit 6 (max.) Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 8 Soil Properties Values Maximum Expansive Potential (%) Non-expansive1 1. Measured on a sample compacted to approximately 95 percent of the maximum dry unit weight as determined by ASTM D698 at optimum moisture content. The sample is confined under a 100 psf surcharge and submerged. 4.2.6 Compaction Requirements Engineered fill should be placed and compacted in horizontal lifts, using equipment and procedures that will produce recommended moisture contents and densities throughout the lift. Item Description Fill lift thickness 9 inches or less in loose thickness when heavy, self- propelled compaction equipment is used 4 to 6 inches in loose thickness when hand-guided equipment (i.e. jumping jack or plate compactor) is used Minimum compaction requirements 95 percent of the maximum dry unit weight as determined by ASTM D698 Moisture content cohesive soil (clay) -1 to +3 % of the optimum moisture content Moisture content cohesionless soil (sand) -3 to +3 % of the optimum moisture content 1. We recommend engineered fill be tested for moisture content and compaction during placement. Should the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved. 2. Specifically, moisture levels should be maintained low enough to allow for satisfactory compaction to be achieved without the fill material pumping when proofrolled. 3. Moisture conditioned clay materials should not be allowed to dry out. A loss of moisture within these materials could result in an increase in the material’s expansive potential. Subsequent wetting of these materials could result in undesirable movement. 4.2.7 Utility Trench Backfill All trench excavations should be made with sufficient working space to permit construction including backfill placement and compaction. All underground piping within or near the proposed structures should be designed with flexible couplings, so minor deviations in alignment do not result in breakage or distress. Utility knockouts in foundation walls should be oversized to accommodate differential movements. It is imperative that utility trenches be properly backfilled with relatively clean materials. If utility trenches are backfilled with relatively clean granular material, they should be capped with at least 18 inches of cohesive fill in non-pavement areas to reduce the infiltration and conveyance of surface water through the trench backfill. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 9 Utility trenches are a common source of water infiltration and migration. All utility trenches that penetrate beneath the buildings should be effectively sealed to restrict water intrusion and flow through the trenches that could migrate below the buildings. We recommend constructing an effective clay “trench plug” that extends at least 5 feet out from the face of the building exteriors. The plug material should consist of clay compacted at a water content at or above the soil’s optimum water content. The clay fill should be placed to completely surround the utility line and be compacted in accordance with recommendations in this report. It is strongly recommended that a representative of Terracon provide full-time observation and compaction testing of trench backfill within building and pavement areas. 4.2.8 Grading and Drainage All grades must be adjusted to provide effective drainage away from the proposed buildings during construction and maintained throughout the life of the proposed project. Infiltration of water into foundation excavations must be prevented during construction. Landscape irrigation adjacent to foundations should be minimized or eliminated. Water permitted to pond near or adjacent to the perimeter of the structures (either during or post-construction) can result in significantly higher soil movements than those discussed in this report. As a result, any estimations of potential movement described in this report cannot be relied upon if positive drainage is not obtained and maintained, and water is allowed to infiltrate the fill and/or subgrade. Exposed ground (if any) should be sloped at a minimum of 10 percent grade for at least 10 feet beyond the perimeter of the proposed buildings, where possible. The use of swales, chases and/or area drains may be required to facilitate drainage in unpaved areas around the perimeter of the buildings. Backfill against foundations and exterior walls should be properly compacted and free of all construction debris to reduce the possibility of moisture infiltration. After construction of the proposed buildings and prior to project completion, we recommend verification of final grading be performed to document positive drainage, as described above, has been achieved. Flatwork and pavements will be subject to post-construction movement. Maximum grades practical should be used for paving and flatwork to prevent areas where water can pond. In addition, allowances in final grades should take into consideration post-construction movement of flatwork, particularly if such movement would be critical. Where paving or flatwork abuts the structures, care should be taken that joints are properly sealed and maintained to prevent the infiltration of surface water. Planters (if any) located adjacent to structures should preferably be self-contained. Sprinkler mains and spray heads should be located a minimum of 5 feet away from the building line(s). Low-volume, drip style landscaped irrigation should not be used near the building. Roof drains should discharge on to pavements or be extended away from the structures a minimum of 10 feet through the use of splash blocks or downspout extensions. A preferred alternative is to have the roof drains discharge by solid pipe to storm sewers or to a detention pond or other appropriate outfall. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 10 4.3 Foundations We recommend the proposed self-storage buildings be constructed on shallow spread footing foundation systems provided the soils below the proposed footings are over-excavated to a depth of 2 feet and replaced with moisture conditioned, properly compacted engineered fill. On-site soils are suitable for reuse as over-excavation backfill below proposed buildings. As an alternative, the proposed buildings may be constructed on a drilled pier foundation system bottomed in bedrock. 4.3.1 Spread Footings - Design Recommendations Description Values Bearing material Properly prepared on-site soil or new, properly placed engineered fill. Maximum allowable bearing pressure 1 2,500 psf Lateral earth pressure coefficients 2 Active, Ka = 0.31 Passive, Kp = 3.3 At-rest, Ko = 0.47 Sliding coefficient 2 µ = 0.5 Moist soil unit weight ɣ = 110 pcf Minimum embedment depth below finished grade 3 30 inches Estimated total movement About 1 inch 1. The recommended maximum allowable bearing pressure assumes any unsuitable fill or soft soils, if encountered, will be over-excavated and either recompacted to 95% the maximum dry unit weight as determined by ASTM D698 or replaced with properly compacted engineered fill. The design bearing pressure applies to a dead load plus design live load condition. The design bearing pressure may be increased by one-third when considering total loads that include wind or seismic conditions. 2. The lateral earth pressure coefficients and sliding coefficients are ultimate values and do not include a factor of safety. The foundation designer should include the appropriate factors of safety. 3. For frost protection and to reduce the effects of seasonal moisture variations in the subgrade soils. The minimum embedment depth is for perimeter footings beneath unheated areas and is relative to lowest adjacent finished grade, typically exterior grade. Footings should be proportioned to reduce differential foundation movement. As discussed, total movement resulting from the assumed structural loads is estimated to be on the order of about 1 inch. Additional foundation movements could occur if water from any source infiltrates the foundation soils; therefore, proper drainage should be provided in the final design and during construction and throughout the life of the structure. Failure to maintain the proper drainage as recommended in the 4.2.8 Grading and Drainage section of this report will nullify the movement estimates provided above. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 11 4.3.2 Spread Footings - Construction Considerations To reduce the potential of “pumping” and softening of the foundation soils at the foundation bearing level and the requirement for corrective work, we suggest the foundation excavation for the proposed buildings be completed remotely with a track-hoe operating outside of the excavation limits. Spread footing construction should only be considered if the estimated foundation movement can be tolerated. Subgrade soils beneath footings should be moisture conditioned and compacted as described in the 4.2 Earthwork section of this report. The moisture content and compaction of subgrade soils should be maintained until foundation construction. Footings and foundation walls should be reinforced as necessary to reduce the potential for distress caused by differential foundation movement. Unstable subgrade conditions are anticipated as excavations approach the groundwater surface. Unstable surfaces will need to be stabilized prior to backfilling excavations and/or constructing the building foundation, floor slab and/or project pavements. The use of angular rock, recycled concrete and/or gravel pushed or “crowded” into the yielding subgrade is considered suitable means of stabilizing the subgrade. The use of geogrid materials in conjunction with gravel could also be considered and could be more cost effective. Unstable subgrade conditions should be observed by Terracon to assess the subgrade and provide suitable alternatives for stabilization. Stabilized areas should be proof-rolled prior to continuing construction to assess the stability of the subgrade. Foundation excavations should be observed by Terracon. If the soil conditions encountered differ significantly from those presented in this report, supplemental recommendations will be required. 4.3.3 Drilled Piers Bottomed in Bedrock - Design Recommendations As an alternative to a spread footing foundation system, the proposed buildings may be constructed on a drilled pier foundation system bottomed in bedrock. Description Value Minimum pier length 18 feet Minimum pier diameter 18 inches Minimum bedrock embedment 1 6 feet Maximum allowable end-bearing pressure 35,000 psf Allowable skin friction (for portion of pier embedded into bedrock 2,500 psf Void thickness (beneath grade beams) 4 inches 1. Drilled piers should be embedded into hard or very hard bedrock materials. Actual structural loads and pier diameters may dictate embedment deeper than the recommended minimum penetration. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 12 Site grading details were not fully understood at the time we prepared this report. If significant fills are planned in the proposed building areas, longer drilled pier lengths may be required. Piers should be considered to work in group action if the horizontal spacing is less than three pier diameters. A minimum practical horizontal clear spacing between piers of at least three diameters should be maintained, and adjacent piers should bear at the same elevation. The capacity of individual piers must be reduced when considering the effects of group action. Capacity reduction is a function of pier spacing and the number of piers within a group. If group action analyses are necessary, capacity reduction factors can be provided for the analyses. To satisfy forces in the horizontal direction using LPILE, piers may be designed for the following lateral load criteria: Parameters Clay Sand and Gravel Sandstone Bedrock LPILE soil type Soft clay Sand (submerged) Stiff clay Effective unit weight (pcf) above groundwater 120 - 120 Effective unit weight (pcf) below groundwater 62 Average undrained shear strength (psf) 500 N/A 9,000 Average angle of internal friction,  (degrees) N/A 35 N/A Coefficient of subgrade reaction, k (pci)* 100 - static 30 - cyclic 60 2,000- static 800 – cyclic Strain, 50 (%) 0.010 N/A 0.004 1. For purposes of LPILE analysis, assume a groundwater depth of about 7 feet below existing ground surface. 4.3.4 Drilled Piers Bottomed in Bedrock - Construction Considerations Drilling to design depth should be possible with conventional single-flight power augers on the majority of the site; however, specialized drilling equipment may be required for very hard bedrock layers. Groundwater/caving soil conditions indicate that temporary steel casing may be required to properly drill and clean piers prior to concrete placement. Groundwater should be removed from each pier hole prior to concrete placement. Pier concrete should be placed immediately after completion of drilling and cleaning. If pier concrete cannot be placed in dry conditions, a tremie should be used for concrete placement. Free-fall concrete placement in piers will only be acceptable if provisions are taken to avoid striking the concrete on the sides of the hole or reinforcing steel. The use of a bottom-dump hopper, or an elephant's trunk discharging near the bottom of the hole where concrete segregation will be minimized, is recommended. Due to potential sloughing and raveling, foundation concrete quantities may exceed calculated geometric volumes. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 13 Casing should be withdrawn in a slow continuous manner maintaining a sufficient head of concrete to prevent infiltration of water or caving soils or the creation of voids in pier concrete. Pier concrete should have a relatively high fluidity when placed in cased pier holes or through a tremie. Pier concrete with slump in the range of 5 to 7 inches is recommended. We recommend the sides of each pier should be mechanically roughened in the bedrock bearing strata. This should be accomplished by a roughening tooth placed on the auger. Shaft bearing surfaces must be cleaned prior to concrete placement. A representative of Terracon should observe the bearing surface and shaft configuration. 4.4 Seismic Considerations Code Used Site Classification 2012 International Building Code (IBC) 1 D 2 1. In general accordance with the 2012 International Building Code, Table 1613.5.2. 2. The 2012 International Building Code (IBC) requires a site soil profile determination extending a depth of 100 feet for seismic site classification. The current scope requested does not include the required 100 foot soil profile determination. The borings completed for this project extended to a maximum depth of about 25½ feet and this seismic site class definition considers that similar soil and bedrock conditions exist below the maximum depth of the subsurface exploration. Additional exploration to deeper depths could be performed to confirm the conditions below the current depth of exploration. Alternatively, a geophysical exploration could be utilized in order to attempt to justify a more favorable seismic site class. However, we believe a higher seismic site class for this site is unlikely. 4.5 Floor Systems A slab-on-grade may be utilized for the interior floor system for the proposed structures provided the soils below the floor are over-excavated to a depth of 12 inches and replaced with moisture conditioned, properly compacted engineered fill. On-site soils are suitable for reuse as over- excavation backfill below proposed buildings. Even when bearing on properly prepared soils, movement of the slab-on-grade floor system is possible should the subgrade soils undergo an increase in moisture content. We estimate movement of about 1 inch is possible. If the owner cannot accept the risk of slab movement, a structural floor should be used. Careful consideration should be taken to the 4.2 Earthwork section of this report to prevent unwanted movement of the floor slab. If the estimated movement cannot be tolerated, a structurally-supported floor system, supported independent of the subgrade materials, is recommended. 4.6 Elevator Pit We assume an elevator pit will be included in the interior of the two-story climate-controlled building. The elevator pit will likely consist of reinforced concrete walls with a concrete base slab. Based on our experience with this type of structure, we anticipate the base slabs will be about 5 feet below the level of the finished floor slab. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 14 4.6.1 Elevator Pit Design Recommendations Subsurface conditions in the elevator pit excavations are anticipated to consist of native clays and sands and gravels. Groundwater was encountered at depths of about 7 feet below existing site grades at the time of our field exploration. However, groundwater levels can and should be expected to fluctuate over time. Depending upon final site grades and elevator pit elevations, groundwater could impact the performance of the pit base slab. If the pit slab is constructed at our within about 4 feet of the level of groundwater, the pit slab should be designed and constructed to resist hydrostatic pressures and uplift due to the effects of buoyancy or it should be protected by an underdrain system for permanent dewatering. “Water-proofing” of the pit will also be needed if permanent dewatering is not used. Terracon should evaluate the groundwater level within each elevator pit area prior to or during construction. The elevator pit walls should be designed for lateral earth pressures imposed by the soil backfill. Earth pressure will primarily be influenced by structural design of the walls, conditions of wall restraint and type, compaction and drainage of backfill. For purposes of design, we have assumed approximately 5 feet of fill will be retained by the pit walls and backfill will consist of the on-site lean clays. If taller walls are planned, or if different type of backfill is used, we should be contacted to review our data and confirm or modify the design criteria presented below. Active earth pressure is commonly used for design of walls (such as free-standing cantilever retaining walls) and assumes some wall rotation and deflection. For walls that can deflect and rotate around the base, the top lateral movements of about ¼ to ½ percent or more of the wall height, lower “active pressures could be considered for design. Use of the “active” condition assumes deflection and thus cracking of walls could occur. For rigid walls where negligible or very little rotation and deflection will occur, “at-rest” lateral earth pressures should be used in the design. Reinforced concrete pit walls should be designed for lateral earth pressures and/or combined hydrostatic and lateral earth pressures at least equal to those indicated in the table in the 4.7 Lateral Earth Pressures section of this report. The lateral earth pressures presented above do not include a factory of safety. As such, appropriate factors of safety should be applied to these values. Furthermore, the lateral earth pressures do not include the influence of surcharge, equipment of floor loading, which should be added. 4.6.2 Elevator Pit Design Recommendations Depending on groundwater conditions at the time of construction and the final depth of the pits, some method of temporary dewatering may be needed during construction. Dewatering should continue through the excavation, foundation construction and backfilling operations to ensure proper construction. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 15 The elevator pit excavations should be observed by the geotechnical engineer to confirm that the subsurface conditions are consistent with those encountered in our test borings. If the soil conditions encountered differ from those presented in this report, supplemental recommendations will be required. Where expansive clays, low strength soils or otherwise unsuitable bearing materials are encountered in the excavation, these materials should be over-excavated to the minimum depth determined by the geotechnical engineer and replaced with approved engineered fill. Terracon should be contacted to evaluate bearing conditions in the elevator pit excavations well in advance of forming foundations. 4.7 Lateral Earth Pressures Reinforced concrete walls with unbalanced backfill levels on opposite sides should be designed for earth pressures at least equal to those indicated in the following table. Earth pressures will be influenced by structural design of the walls, conditions of wall restraint, methods of construction and/or compaction and the strength of the materials being restrained. Two wall restraint conditions are shown. Active earth pressure is commonly used for design of free-standing cantilever retaining walls and assumes wall movement. The "at-rest" condition assumes no wall movement. The recommended design lateral earth pressures do not include a factor of safety and do not provide for possible hydrostatic pressure on the walls. EARTH PRESSURE COEFFICIENTS Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 16 Earth Pressure Conditions Coefficient for Backfill Type Equivalent Fluid Density (pcf) Surcharge Pressure, p1 (psf) Earth Pressure, p2 (psf) Active (Ka) Sands and Gravels - 0.22 Lean Clay - 0.33 26 40 (0.22)S (0.33)S (26)H (40)H At-Rest (Ko) Sands and Gravels - 0.36 Lean Clay - 0.50 43 60 (0.36)S (0.50)S (43)H (60)H Passive (Kp) Sands and Gravels – 4.6 Lean Clay – 3.0 552 360 --- --- --- --- Applicable conditions to the above include:  For active earth pressure, wall must rotate about base, with top lateral movements of about 0.002 H to 0.004 H, where H is wall height;  For passive earth pressure to develop, wall must move horizontally to mobilize resistance;  Uniform surcharge, where S is surcharge pressure;  In-situ soil backfill weight a maximum of 120 pcf;  Horizontal backfill, compacted between 95 and 98 percent of maximum dry unit weight as determined by ASTM D698;  Loading from heavy compaction equipment not included;  No hydrostatic pressures acting on wall;  No dynamic loading;  No safety factor included in soil parameters; and  Ignore passive pressure in frost zone. To control hydrostatic pressure behind the wall we recommend that a drain be installed at the foundation wall with a collection pipe leading to a reliable discharge. If this is not possible, then combined hydrostatic and lateral earth pressures should be calculated for lean clay backfill using an equivalent fluid weighing 90 and 100 pcf for active and at-rest conditions, respectively. For Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 17 grading and paving. All pavement areas should be moisture conditioned and properly compacted to the recommendations in this report immediately prior to paving. 4.8.2 Pavements – Design Recommendations Design of new privately-maintained pavements for the project has been based on the procedures described by the National Asphalt Pavement Associations (NAPA) and the American Concrete Institute (ACI). We assumed the following design parameters for NAPA flexible pavement thickness design:  Automobile Parking Areas  Class I - Parking stalls and parking lots for cars and pick-up trucks, with Equivalent Single Axle Load (ESAL) up to 7,000 over 20 years  Main Traffic Corridors  Class II – Parking lots with a maximum of 10 trucks per day with Equivalent Single Axle Load (ESAL) up to 27,000 over 20 years (Including trash trucks)  Subgrade Soil Characteristics  USCS Classification – CL, classified by NAPA as poor We assumed the following design parameters for ACI rigid pavement thickness design based upon the average daily truck traffic (ADTT):  Automobile Parking Areas  ACI Category A: Automobile parking with an ADTT of 1 over 20 years  Main Traffic Corridors  ACI Category A: Automobile parking area and service lanes with an ADTT of up to 10 over 20 years  Subgrade Soil Characteristics  USCS Classification – CL  Concrete modulus of rupture value of 600 psi We should be contacted to confirm and/or modify the recommendations contained herein if actual traffic volumes differ from the assumed values shown above. Recommended alternatives for flexible and rigid pavements are summarized for each traffic area as follows: Traffic Area Alternative Recommended Pavement Thicknesses (Inches) Asphaltic Concrete Surface Aggregate Base Course1 Portland Cement Concrete Total Automobile Parking Areas A 4 4 -- 8 Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 18 Traffic Area Alternative Recommended Pavement Thicknesses (Inches) Asphaltic Concrete Surface Aggregate Base Course1 Portland Cement Concrete Total (NAPA Class I and ACI Category A) B - - 5 5 Main Traffic Corridors (NAPA Class II and ACI Category A) A 4½ 6 - 10½ B - - 6 6 Aggregate base course (if used on the site) should consist of a blend of sand and gravel which meets strict specifications for quality and gradation. Use of materials meeting Colorado Department of Transportation (CDOT) Class 5 or 6 specifications is recommended for aggregate base course. Aggregate base course should be placed in lifts not exceeding 6 inches and compacted to a minimum of 95 percent of the maximum dry unit weight as determined by ASTM D698. Asphaltic concrete should be composed of a mixture of aggregate, filler and additives (if required) and approved bituminous material. The asphalt concrete should conform to approved mix designs stating the Superpave properties, optimum asphalt content, job mix formula and recommended mixing and placing temperatures. Aggregate used in asphalt concrete should meet particular gradations. Material meeting CDOT Grading S or SX specifications or equivalent is recommended for asphalt concrete. Mix designs should be submitted prior to construction to verify their adequacy. Asphalt material should be placed in maximum 3-inch lifts and compacted within a range of 92 to 96 percent of the theoretical maximum (Rice) density (ASTM D2041). Where rigid pavements are used, the concrete should be produced from an approved mix design with the following minimum properties: Properties Value Compressive strength 4,000 psi Cement type1 Type V portland cement Entrained air content (%) 5 to 8 Concrete aggregate ASTM C33 and CDOT section 703 1. If concrete is placed on aggregate base course Type I or II portland cement may be used as it will not be in contact with the soil. Concrete should be deposited by truck mixers or agitators and placed a maximum of 90 minutes from the time the water is added to the mix. Longitudinal and transverse joints should be provided as needed in concrete pavements for expansion/contraction and isolation per ACI 325. The location and extent of joints should be based upon the final pavement geometry. Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 19 Although not required for structural support, a minimum 4-inch thick aggregate base course layer is recommended for the PCC pavements to help reduce the potential for slab curl, shrinkage cracking, and subgrade “pumping” through joints. Proper joint spacing will also be required for PCC pavements to prevent excessive slab curling and shrinkage cracking. All joints should be sealed to prevent entry of foreign material and dowelled where necessary for load transfer. For areas subject to concentrated and repetitive loading conditions (if any) such as dumpster pads, truck delivery docks and ingress/egress aprons, we recommend using a portland cement concrete pavement with a thickness of at least 6 inches underlain by at least 4 inches of granular base. Prior to placement of the granular base, the areas should be thoroughly proofrolled. For dumpster pads, the concrete pavement area should be large enough to support the container and tipping axle of the refuse truck. Pavement performance is affected by its surroundings. In addition to providing preventive maintenance, the civil engineer should consider the following recommendations in the design and layout of pavements:  Site grades should slope a minimum of 2 percent away from the pavements;  The subgrade and the pavement surface have a minimum 2 percent slope to promote proper surface drainage;  Consider appropriate edge drainage and pavement under drain systems;  Install pavement drainage surrounding areas anticipated for frequent wetting;  Install joint sealant and seal cracks immediately;  Seal all landscaped areas in, or adjacent to pavements to reduce moisture migration to subgrade soils; and  Placing compacted, low permeability backfill against the exterior side of curb and gutter. 4.8.3 Pavements – Construction Considerations Openings in pavement, such as landscape islands, are sources for water infiltration into surrounding pavements. Water collects in the islands and migrates into the surrounding subgrade soils thereby degrading support of the pavement. This is especially applicable for islands with raised concrete curbs, irrigated foliage, and low permeability near-surface soils. The civil design for the pavements with these conditions should include features to restrict or to collect and discharge excess water from the islands. Examples of features are edge drains connected to the storm water collection system or other suitable outlet and impermeable barriers preventing lateral migration of water such as a cutoff wall installed to a depth below the pavement structure. 4.8.4 Pavements – Maintenance Preventative maintenance should be planned and provided for an ongoing pavement management program in order to enhance future pavement performance. Preventive maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching) and global maintenance (e.g. surface sealing). Preventative maintenance is usually the first Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable 20 priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements. 5.0 GENERAL COMMENTS Terracon should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications. Terracon also should be retained to provide observation and testing services during grading, excavation, foundation construction and other earth-related construction phases of the project. The analysis and recommendations presented in this report are based upon the data obtained from the borings performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between borings, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, and bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as described in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing. APPENDIX A FIELD EXPLORATION TOPOGRAPHIC MAP IMAGE COURTESY OF THE U.S. GEOLOGICAL SURVEY QUADRANGLES INCLUDE: FORT COLLINS, CO (1984). SITE LOCATION MAP BETCO Self-Storage Northeast of Conifer Street and Red Cedar Circle Fort Collins, CO 1901 Sharp Point Dr Ste C Fort Collins, CO 80525-4429 20165074 DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES Project Manager: Drawn by: Checked by: Approved by: MGH EDB EDB EDB 8/22/2016 Project No. File Name: Date: A-1 Exhibit SITE Scale: 1”=2,000’ LEGEND APPROXIMATE BORING LOCATION APPROXIMATE TEMPORARY BENCHMARK (top nut of yellow fire hydrant) EXPLORATION PLAN 1901 Sharp Point Dr Ste C Fort Collins, CO 80525-4429 20165074 AERIAL PHOTOGRAPHY PROVIDED BY MICROSOFT BING MAPS BETCO Self-Storage Northeast of Conifer Street and Red Cedar Circle Fort Collins, CO DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES Project Manager: Drawn by: Checked by: Approved by: MGH EDB EDB EDB 8/22/2016 Scale: Project No. File Name: Date: AS SHOWN A-2 Exhibit Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable Exhibit A-3 Field Exploration Description The locations of borings were based upon the proposed development shown on the provided site plan. The borings were located in the field by measuring from existing site features. The ground surface elevation was surveyed at each boring location referencing the temporary benchmark shown on Exhibit A-2 using an engineer’s level. The borings were drilled with a CME-75 truck-mounted rotary drill rig with solid-stem augers. During the drilling operations, lithologic logs of the borings were recorded by the field engineer. Disturbed samples were obtained at selected intervals utilizing a 2-inch outside diameter split- spoon sampler and a 3-inch outside diameter ring-barrel sampler. Disturbed bulk samples were obtained from auger cuttings. Penetration resistance values were recorded in a manner similar to the standard penetration test (SPT). This test consists of driving the sampler into the ground with a 140-pound hammer free-falling through a distance of 30 inches. The number of blows required to advance the ring-barrel sampler 12 inches (18 inches for standard split-spoon samplers, final 12 inches are recorded) or the interval indicated, is recorded as a standard penetration resistance value (N-value). The blow count values are indicated on the boring logs at the respective sample depths. Ring-barrel sample blow counts are not considered N-values. A CME automatic SPT hammer was used to advance the samplers in the borings performed on this site. A greater efficiency is typically achieved with the automatic hammer compared to the conventional safety hammer operated with a cathead and rope. Published correlations between the SPT values and soil properties are based on the lower efficiency cathead and rope method. This higher efficiency affects the standard penetration resistance blow count value by increasing the penetration per hammer blow over what would be obtained using the cathead and rope method. The effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of the subsurface information for this report. The standard penetration test provides a reasonable indication of the in-place density of sandy type materials, but only provides an indication of the relative stiffness of cohesive materials since the blow count in these soils may be affected by the moisture content of the soil. In addition, considerable care should be exercised in interpreting the N-values in gravelly soils, particularly where the size of the gravel particle exceeds the inside diameter of the sampler. Groundwater measurements were obtained in the borings at the time of site exploration and several days after drilling. After subsequent groundwater measurements were obtained, the borings were backfilled with auger cuttings and sand (if needed) and patched (if needed). Some settlement of the backfill and/or patch may occur and should be repaired as soon as possible. 16 26 7 10 23 27 19 97 27-20-7 97.5 91 78 64 3-2-2 N=4 2-2 5-9-12 N=21 19-50/6" N=69/12" 30-50/5" N=80/11" N=50/1" N=50/1" N=50/0" 0.5 7.0 20.0 34.0 6-INCH VEGETATIVE LAYER SILTY CLAY WITH SAND (CL-ML), with gravel, light brown, soft to medium stiff POORLY GRADED SAND WITH GRAVEL, with cobbles, coarse to medium grained, reddish-brown, medium dense to dense SEDIMENTARY BEDROCK - SANDSTONE, yellowish-brown to gray, very hard Boring Terminated at 34 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4-inch solid-stem auger Abandonment Method: Boring backfilled with soil cuttings upon completion. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/10/2016 BORING LOG NO. 1 CLIENT: Hauser Architects PC Loveland, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/10/2016 Exhibit: A-4 11 13 2 8 22 21 18 21 108 100 93.5 81 66.5 20-27 +3.5/150 6-6-4 N=10 12-13-13 N=26 10-16-14 N=30 12-37-45 N=82 N=50/4" N=50/3" N=50/1" 0.5 7.0 19.5 34.1 6-INCH VEGETATIVE LAYER SILTY CLAY WITH SAND, with gravel, light brown, stiff POORLY GRADED SAND WITH GRAVEL, with silt and cobbles, coarse to medium grained, reddish-brown, medium dense to dense SEDIMENTARY BEDROCK - SANDSTONE, yellowish-brown, very hard Boring Terminated at 34.1 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4-inch solid-stem auger Abandonment Method: Boring backfilled with soil cuttings upon completion. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/11/2016 BORING LOG NO. 2 CLIENT: Hauser Architects PC Loveland, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/11/2016 Exhibit: A-5 416 14 20 4 11 19 18 16 16 115 107 25-18-7 92 78 66 8-9 3-4 9-16-16 N=32 17-21-28 N=49 20-37-50/3" N=87/9" N=50/1" N=50/2" N=50/1" 8.0 22.0 34.1 SANDY SILTY CLAY, with gravel, brown to reddish-brown, medium stiff to stiff POORLY GRADED SAND WITH GRAVEL, with cobbles, coarse to medium grained, reddish-brown, dense to very dense SEDIMENTARY BEDROCK - SANDSTONE, yellowish-brown to gray, very hard Boring Terminated at 34.1 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 6-inch hollow-stem auger Abandonment Method: Boring backfilled with soil cuttings upon completion. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/11/2016 BORING LOG NO. 3 CLIENT: Hauser Architects PC Loveland, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/11/2016 Exhibit: A-6 See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory 12 2 21 13 24 18 20 NP 95 78.5 69.5 68.5 65.5 7-9-11 N=20 7-6 9-10-12 N=22 36-50/5" N=86/11' 27-50/3" N=77/9" N=50/3" N=50/3" N=50/2" 4.5 21.0 30.0 31.0 34.2 SANDY SILTY CLAY, with gravel, brown to reddish-brown, stiff to very stiff POORLY GRADED SAND WITH GRAVEL (SP), with cobbles, coarse to medium grained, reddish-brown, medium dense to dense SEDIMENTARY BEDROCK - SANDSTONE, yellowish-brown to gray, very hard 2 foot layer of cemented bedrock at 30 feet below existing site grades Boring Terminated at 34.2 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 6-inch hollow-stem auger Abandonment Method: Boring backfilled with soil cuttings upon completion. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/11/2016 BORING LOG NO. 4 CLIENT: Hauser Architects PC Loveland, Colorado 20 21 8 18 22 24 21 20 99 96 89.5 76.5 62 0.0/500 4-3-2 N=5 0-1 6-12-15 N=27 11-33-50 N=83 N=50/5" N=50/3" N=50/3" N=50/4" 0.5 7.0 20.0 34.4 6-INCH VEGETATIVE LAYER SILTY CLAY WITH SAND, with gravel, light brown, very soft to medium stiff POORLY GRADED SAND WITH GRAVEL, with cobbles, fine to coarse grained, reddish-brown, medium dense to dense SEDIMENTARY BEDROCK - SANDSTONE, yellowish-brown to gray, very hard Boring Terminated at 34.4 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 6-inch hollow-stem auger Abandonment Method: Boring backfilled with soil cuttings upon completion. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/11/2016 BORING LOG NO. 5 CLIENT: Hauser Architects PC Loveland, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/11/2016 Exhibit: A-8 13 20 11 9 113 38-17-21 99 90.5 84 10-12 4-4-4 N=8 8-13-9 N=22 6-17-18 N=35 0.5 9.0 15.5 6-INCH VEGETATIVE LAYER LEAN CLAY (CL), with gravel, light brown to brown, stiff to very stiff POORLY GRADED SAND WITH GRAVEL, with cobbles, coarse to medium grained, reddish-brown to brown, medium dense to dense Boring Terminated at 15.5 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4-inch solid-stem auger Abandonment Method: Temporary piezometer installed. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/11/2016 BORING LOG NO. 6 CLIENT: Hauser Architects PC Loveland, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/11/2016 Exhibit: A-9 See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) 4319 9 14 17 18 110 31-17-14 97.5 89 82.5 3-4-5 N=9 3-5 6-9-12 N=21 13-13-15 N=28 0.5 9.0 15.5 6-INCH VEGETATIVE LAYER LEAN CLAY (CL), with gravel, light brown to brown, medium stiff to stiff POORLY GRADED SAND WITH GRAVEL, with cobbles, coarse to medium grained, reddish-brown to brown, medium dense Boring Terminated at 15.5 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic GRAPHIC LOG THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20165074.GPJ TERRACON2015.GDT 8/25/16 Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4-inch solid-stem auger Abandonment Method: Temporary piezometer installed. 1901 Sharp Point Dr Ste C Fort Collins, CO Notes: Project No.: 20165074 Drill Rig: CME-75 Boring Started: 8/11/2016 BORING LOG NO. 7 CLIENT: Hauser Architects PC Loveland, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/11/2016 Exhibit: A-10 See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) APPENDIX B LABORATORY TESTING Geotechnical Engineering Report BETCO Self-Storage ■ Fort Collins, Colorado August 25, 2016 ■ Terracon Project No. 20165074 Responsive ■ Resourceful ■ Reliable Exhibit B-1 Laboratory Testing Description The soil and bedrock samples retrieved during the field exploration were returned to the laboratory for observation by the project geotechnical engineer. At that time, the field descriptions were reviewed and an applicable laboratory testing program was formulated to determine engineering properties of the subsurface materials. Laboratory tests were conducted on selected soil and bedrock samples. The results of these tests are presented on the boring logs and in this appendix. The test results were used for the geotechnical engineering analyses, and the development of foundation and earthwork recommendations. The laboratory tests were performed in general accordance with applicable locally accepted standards. Soil samples were classified in general accordance with the Unified Soil Classification System described in Appendix C. Rock samples were visually classified in general accordance with the description of rock properties presented in Appendix C. Procedural standards noted in this report are for reference to methodology in general. In some cases variations to methods are applied as a result of local practice or professional judgment.  Water content  Plasticity index  Grain-size distribution  Consolidation/swell  Unconfined Compressive strength  Dry density  Water-soluble sulfate content 0 10 20 30 40 50 60 0 20 40 60 80 100 CL or OL CH or OH ML or OL MH or OH Boring ID Depth PL PI Description SILTY CLAY with SAND SANDY SILTY CLAY POORLY GRADED SAND with GRAVEL LEAN CLAY LEAN CLAY CL-ML CL-ML SP CL CL Fines P L A S T I C I T Y I N D E X LIQUID LIMIT "U" Line "A" Line 27 25 NP 38 31 20 18 NP 17 17 7 7 NP 21 14 71 59 3 87 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 100 10 1 0.1 0.01 0.001 1 3 4 6 7 27 25 NP 38 31 0.79 0.08 2.318 2 19 19 2 12.5 6 16 20 30 40 50 1.5 6 200 8 10 0.0 2.2 17.0 0.0 0.9 0.289 14 71.2 59.0 2.7 -4 -2 0 2 4 6 8 10 100 1,000 10,000 AXIAL STRAIN, % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D4546 NOTES: The sample exhibited 3.5 percent swell upon wetting under an applied pressure of 150 psf. Specimen Identification Classification , pcf 2 108 11 WC, % 2 - 3 ft PROJECT NUMBER: 20165074 PROJECT: BETCO Self-Storage SITE: Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado CLIENT: Hauser Architects PC Loveland, Colorado EXHIBIT: B-4 1901 Sharp Point Dr Ste C Fort Collins, CO LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. TC_CONSOL_STRAIN-USCS 20165074.GPJ TERRACON2012.GDT 8/24/16 -4 -2 0 2 4 6 8 10 100 1,000 10,000 AXIAL STRAIN, % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D4546 NOTES: The sample exhibited no movement upon wetting under an applied pressure of 500 psf. Specimen Identification Classification , pcf 5 99 21 WC, % 4 - 5 ft PROJECT NUMBER: 20165074 PROJECT: BETCO Self-Storage SITE: Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado CLIENT: Hauser Architects PC Loveland, Colorado EXHIBIT: B-5 1901 Sharp Point Dr Ste C Fort Collins, CO LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. TC_CONSOL_STRAIN-USCS 20165074.GPJ TERRACON2012.GDT 8/24/16 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 0 2 4 6 8 10 LL PL PI 2.41 3.99 Percent < #200 Sieve 59 AXIAL STRAIN - % Remarks: SPECIMEN FAILURE PHOTOGRAPH SAMPLE DESCRIPTION: SANDY SILTY CLAY(CL-ML) 25 18 7 Unconfined Compressive Strength (psf) Undrained Shear Strength: (psf) UNCONFINED COMPRESSION TEST ASTM D2166 208 SAMPLE TYPE: D&M RING Assumed Specific Gravity: Calculated Void Ratio: Height / Diameter Ratio: SPECIMEN TEST DATA 1.66 6.02 Moisture Content: % Dry Density: pcf Diameter: in. Height: in. Calculated Saturation: % Failure Strain: % Strain Rate: in/min COMPRESSIVE STRESS - psf 20 107 416 SAMPLE LOCATION: 3 @ 4 - 5 feet PROJECT NUMBER: 20165074 PROJECT: BETCO Self-Storage SITE: Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado CLIENT: Hauser Architects PC Loveland, Colorado EXHIBIT: B-6 1901 Sharp Point Dr Ste C Fort Collins, CO LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. UNCONFINED WITH PHOTOS 20165074.GPJ TERRACON2012.GDT 8/24/16 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 0 2 4 6 8 10 LL PL PI 2.41 4.87 Percent < #200 Sieve 85 AXIAL STRAIN - % Remarks: SPECIMEN FAILURE PHOTOGRAPH SAMPLE DESCRIPTION: LEAN CLAY(CL) 31 17 14 Unconfined Compressive Strength (psf) Undrained Shear Strength: (psf) UNCONFINED COMPRESSION TEST ASTM D2166 2159 SAMPLE TYPE: D&M RING Assumed Specific Gravity: Calculated Void Ratio: Height / Diameter Ratio: SPECIMEN TEST DATA 2.02 3.70 Moisture Content: % Dry Density: pcf Diameter: in. Height: in. Calculated Saturation: % Failure Strain: % Strain Rate: in/min COMPRESSIVE STRESS - psf 14 109 4319 SAMPLE LOCATION: 7 @ 4 - 5 feet PROJECT NUMBER: 20165074 PROJECT: BETCO Self-Storage SITE: Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado CLIENT: Hauser Architects PC Loveland, Colorado EXHIBIT: B-7 1901 Sharp Point Dr Ste C Fort Collins, CO LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. UNCONFINED WITH PHOTOS 20165074.GPJ TERRACON2012.GDT 8/24/16 TASK NO: 160818014 Analytical Results Terracon, Inc. - Fort Collins Eric D. Bernhardt Company: Report To: Company: Bill To: 1901 Sharp Point Drive Suite C Fort Collins CO 80525 Accounts Payable Terracon, Inc. - A/P 18001 W. 106th St Suite 300 Olathe KS 66061 20165074 Date Reported: 8/25/16 Task No.: 160818014 Matrix: Soil - Geotech Date Received: 8/18/16 Client Project: Client PO: CustomerFt Sample ID 20165074 - BH#1 @ 4-5 Test Method Lab Number: 160818014-01 Result Sulfate - Water Soluble 0.572 % AASHTO T290-91/ ASTM D4327 CustomerFt Sample ID 20165074 - BH#4 @ 2-3.5 Test Method Lab Number: 160818014-02 Result Sulfate - Water Soluble 0.032 % AASHTO T290-91/ ASTM D4327 240 South Main Street / Brighton, CO 80601-0507 / 303-659-2313 Mailing Address: P.O. Box 507 / Brighton, CO 80601-0507 / Fax: 303-659-2315 DATA APPROVED FOR RELEASE BY Abbreviations/ References: 160818014 AASHTO - American Association of State Highway and Transportation Officials. ASTM - American Society for Testing and Materials. ASA - American Society of Agronomy. DIPRA - Ductile Iron Pipe Research Association Handbook of Ductile Iron Pipe. APPENDIX C SUPPORTING DOCUMENTS Exhibit: C-1 Unconfined Compressive Strength Qu, (psf) 500 to 1,000 2,000 to 4,000 4,000 to 8,000 1,000 to 2,000 less than 500 > 8,000 Non-plastic Low Medium High DESCRIPTION OF SYMBOLS AND ABBREVIATIONS SAMPLING WATER LEVEL FIELD TESTS GENERAL NOTES Over 12 in. (300 mm) 12 in. to 3 in. (300mm to 75mm) 3 in. to #4 sieve (75mm to 4.75 mm) #4 to #200 sieve (4.75mm to 0.075mm Passing #200 sieve (0.075mm) Particle Size < 5 5 - 12 > 12 Percent of Dry Weight Descriptive Term(s) of other constituents RELATIVE PROPORTIONS OF FINES 0 1 - 10 11 - 30 > 30 Plasticity Index Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency. LOCATION AND ELEVATION NOTES Percent of Dry Weight Major Component of Sample Trace With Modifier RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY Trace With Modifier DESCRIPTIVE SOIL CLASSIFICATION Boulders Cobbles Gravel Sand UNIFIED SOIL CLASSIFICATION SYSTEM Exhibit C-2 Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Soil Classification Group Symbol Group Name B Coarse Grained Soils: More than 50% retained on No. 200 sieve Gravels: More than 50% of coarse fraction retained on No. 4 sieve Clean Gravels: Less than 5% fines C Cu  4 and 1  Cc  3 E GW Well-graded gravel F Cu  4 and/or 1  Cc  3 E GP Poorly graded gravel F Gravels with Fines: More than 12% fines C Fines classify as ML or MH GM Silty gravel F,G,H Fines classify as CL or CH GC Clayey gravel F,G,H Sands: 50% or more of coarse fraction passes No. 4 sieve Clean Sands: Less than 5% fines D Cu  6 and 1  Cc  3 E SW Well-graded sand I Cu  6 and/or 1  Cc  3 E SP Poorly graded sand I Sands with Fines: More than 12% fines D Fines classify as ML or MH SM Silty sand G,H,I Fines classify as CL or CH SC Clayey sand G,H,I Fine-Grained Soils: 50% or more passes the No. 200 sieve Silts and Clays: Liquid limit less than 50 Inorganic: PI  7 and plots on or above “A” line J CL Lean clay K,L,M PI  4 or plots below “A” line J ML Silt K,L,M Organic: Liquid limit - oven dried  0.75 OL Organic clay K,L,M,N Liquid limit - not dried Organic silt K,L,M,O Silts and Clays: Liquid limit 50 or more Inorganic: PI plots on or above “A” line CH Fat clay K,L,M PI plots below “A” line MH Elastic Silt K,L,M Organic: Liquid limit - oven dried  0.75 OH Organic clay K,L,M,P Liquid limit - not dried Organic silt K,L,M,Q Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-inch (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles DESCRIPTION OF ROCK PROPERTIES Exhibit C-3 WEATHERING Fresh Rock fresh, crystals bright, few joints may show slight staining. Rock rings under hammer if crystalline. Very slight Rock generally fresh, joints stained, some joints may show thin clay coatings, crystals in broken face show bright. Rock rings under hammer if crystalline. Slight Rock generally fresh, joints stained, and discoloration extends into rock up to 1 in. Joints may contain clay. In granitoid rocks some occasional feldspar crystals are dull and discolored. Crystalline rocks ring under hammer. Moderate Significant portions of rock show discoloration and weathering effects. In granitoid rocks, most feldspars are dull and discolored; some show clayey. Rock has dull sound under hammer and shows significant loss of strength as compared with fresh rock. Moderately severe All rock except quartz discolored or stained. In granitoid rocks, all feldspars dull and discolored and majority show kaolinization. Rock shows severe loss of strength and can be excavated with geologist’s pick. Severe All rock except quartz discolored or stained. Rock “fabric” clear and evident, but reduced in strength to strong soil. In granitoid rocks, all feldspars kaolinized to some extent. Some fragments of strong rock usually left. Very severe All rock except quartz discolored or stained. Rock “fabric” discernible, but mass effectively reduced to “soil” with only fragments of strong rock remaining. Complete Rock reduced to ”soil”. Rock “fabric” not discernible or discernible only in small, scattered locations. Quartz may be present as dikes or stringers. HARDNESS (for engineering description of rock – not to be confused with Moh’s scale for minerals) Very hard Cannot be scratched with knife or sharp pick. Breaking of hand specimens requires several hard blows of geologist’s pick. Hard Can be scratched with knife or pick only with difficulty. Hard blow of hammer required to detach hand specimen. Moderately hard Can be scratched with knife or pick. Gouges or grooves to ¼ in. deep can be excavated by hard blow of point of a geologist’s pick. Hand specimens can be detached by moderate blow. Medium Can be grooved or gouged 1/16 in. deep by firm pressure on knife or pick point. Can be excavated in small chips to pieces about 1-in. maximum size by hard blows of the point of a geologist’s pick. Soft Can be gouged or grooved readily with knife or pick point. Can be excavated in chips to pieces several inches in size by moderate blows of a pick point. Small thin pieces can be broken by finger pressure. Very soft Can be carved with knife. Can be excavated readily with point of pick. Pieces 1-in. or more in thickness can be broken with finger pressure. Can be scratched readily by fingernail. Joint, Bedding, and Foliation Spacing in Rock a Spacing Joints Bedding/Foliation Less than 2 in. Very close Very thin 2 in. – 1 ft. Close Thin 1 ft. – 3 ft. Moderately close Medium 3 ft. – 10 ft. Wide Thick More than 10 ft. Very wide Very thick a. Spacing refers to the distance normal to the planes, of the described feature, which are parallel to each other or nearly so. Rock Quality Designator (RQD) a Joint Openness Descriptors RQD, as a percentage Diagnostic description Openness Descriptor Exceeding 90 Excellent No Visible Separation Tight 90 – 75 Good Less than 1/32 in. Slightly Open 75 – 50 Fair 1/32 to 1/8 in. Moderately Open 50 – 25 Poor 1/8 to 3/8 in. Open Less than 25 Very poor 3/8 in. to 0.1 ft. Moderately Wide a. RQD (given as a percentage) = length of core in pieces Greater than 0.1 ft. Wide 4 in. and longer/length of run. References: American Society of Civil Engineers. Manuals and Reports on Engineering Practice - No. 56. Subsurface Investigation for Design and Construction of Foundations of Buildings. New York: American Society of Civil Engineers, 1976. U.S. Department of the Interior, Bureau of Reclamation, Engineering Geology Field Manual. Exhibit C-4 LABORATORY TEST SIGNIFICANCE AND PURPOSE Test Significance Purpose California Bearing Ratio Used to evaluate the potential strength of subgrade soil, subbase, and base course material, including recycled materials for use in road and airfield pavements. Pavement Thickness Design Consolidation Used to develop an estimate of both the rate and amount of both differential and total settlement of a structure. Foundation Design Direct Shear Used to determine the consolidated drained shear strength of soil or rock. Bearing Capacity, Foundation Design, and Slope Stability Dry Density Used to determine the in-place density of natural, inorganic, fine-grained soils. Index Property Soil Behavior Expansion Used to measure the expansive potential of fine-grained soil and to provide a basis for swell potential classification. Foundation and Slab Design Gradation Used for the quantitative determination of the distribution of particle sizes in soil. Soil Classification Liquid & Plastic Limit, Plasticity Index Used as an integral part of engineering classification systems to characterize the fine-grained fraction of soils, and to specify the fine-grained fraction of construction materials. Soil Classification Permeability Used to determine the capacity of soil or rock to conduct a liquid or gas. Groundwater Flow Analysis pH Used to determine the degree of acidity or alkalinity of a soil. Corrosion Potential Resistivity Used to indicate the relative ability of a soil medium to carry electrical currents. Corrosion Potential R-Value Used to evaluate the potential strength of subgrade soil, subbase, and base course material, including recycled materials for use in road and airfield pavements. Pavement Thickness Design Soluble Sulfate Used to determine the quantitative amount of soluble sulfates within a soil mass. Exhibit C-5 REPORT TERMINOLOGY (Based on ASTM D653) Allowable Soil Bearing Capacity The recommended maximum contact stress developed at the interface of the foundation element and the supporting material. Alluvium Soil, the constituents of which have been transported in suspension by flowing water and subsequently deposited by sedimentation. Aggregate Base Course A layer of specified material placed on a subgrade or subbase usually beneath slabs or pavements. Backfill A specified material placed and compacted in a confined area. Bedrock A natural aggregate of mineral grains connected by strong and permanent cohesive forces. Usually requires drilling, wedging, blasting or other methods of extraordinary force for excavation. Bench A horizontal surface in a sloped deposit. Caisson (Drilled Pier or Shaft) A concrete foundation element cast in a circular excavation which may have an enlarged base. Sometimes referred to as a cast-in-place pier or drilled shaft. Coefficient of Friction A constant proportionality factor relating normal stress and the corresponding shear stress at which sliding starts between the two surfaces. Colluvium Soil, the constituents of which have been deposited chiefly by gravity such as at the foot of a slope or cliff. Compaction The densification of a soil by means of mechanical manipulation Concrete Slab-on- Grade A concrete surface layer cast directly upon a base, subbase or subgrade, and typically used as a floor system. Differential Movement Unequal settlement or heave between, or within foundation elements of structure. Earth Pressure The pressure exerted by soil on any boundary such as a foundation wall. ESAL Equivalent Single Axle Load, a criteria used to convert traffic to a uniform standard, (18,000 pound axle loads). Engineered Fill Specified material placed and compacted to specified density and/or moisture conditions under observations of a representative of a geotechnical engineer. Equivalent Fluid A hypothetical fluid having a unit weight such that it will produce a pressure against a lateral support presumed to be equivalent to that produced by the actual soil. This simplified approach is valid only when deformation conditions are such that the pressure increases linearly with depth and the wall friction is neglected. Existing Fill (or Man-Made Fill) Materials deposited throughout the action of man prior to exploration of the site. Existing Grade The ground surface at the time of field exploration. Exhibit C-6 REPORT TERMINOLOGY (Based on ASTM D653) Expansive Potential The potential of a soil to expand (increase in volume) due to absorption of moisture. Finished Grade The final grade created as a part of the project. Footing A portion of the foundation of a structure that transmits loads directly to the soil. Foundation The lower part of a structure that transmits the loads to the soil or bedrock. Frost Depth The depth at which the ground becomes frozen during the winter season. Grade Beam A foundation element or wall, typically constructed of reinforced concrete, used to span between other foundation elements such as drilled piers. Groundwater Subsurface water found in the zone of saturation of soils or within fractures in bedrock. Heave Upward movement. Lithologic The characteristics which describe the composition and texture of soil and rock by observation. Native Grade The naturally occurring ground surface. Native Soil Naturally occurring on-site soil, sometimes referred to as natural soil. Optimum Moisture Content The water content at which a soil can be compacted to a maximum dry unit weight by a given compactive effort. Perched Water Groundwater, usually of limited area maintained above a normal water elevation by the presence of an intervening relatively impervious continuous stratum. Scarify To mechanically loosen soil or break down existing soil structure. Settlement Downward movement. Skin Friction (Side Shear) The frictional resistance developed between soil and an element of the structure such as a drilled pier. Soil (Earth) Sediments or other unconsolidated accumulations of solid particles produced by the physical and chemical disintegration of rocks, and which may or may not contain organic matter. Strain The change in length per unit of length in a given direction. Stress The force per unit area acting within a soil mass. Strip To remove from present location. Subbase A layer of specified material in a pavement system between the subgrade and base course. Subgrade The soil prepared and compacted to support a structure, slab or pavement system. Corrosion Potential Unconfined Compression To obtain the approximate compressive strength of soils that possess sufficient cohesion to permit testing in the unconfined state. Bearing Capacity Analysis for Foundations Water Content Used to determine the quantitative amount of water in a soil mass. Index Property Soil Behavior or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay E Cu = D60/D10 Cc = 10 60 2 30 D x D (D ) F If soil contains  15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. H If fines are organic, add “with organic fines” to group name. I If soil contains  15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains  30% plus No. 200 predominantly sand, add “sandy” to group name. M If soil contains  30% plus No. 200, predominantly gravel, add “gravelly” to group name. N PI  4 and plots on or above “A” line. O PI  4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line. Silt or Clay Descriptive Term(s) of other constituents N (HP) (T) (DCP) (PID) (OVA) < 15 15 - 29 > 30 Term PLASTICITY DESCRIPTION Water levels indicated on the soil boring logs are the levels measured in the borehole at the times indicated. Groundwater level variations will occur over time. In low permeability soils, accurate determination of groundwater levels is not possible with short term water level observations. Water Level After a Specified Period of Time Water Level After a Specified Period of Time Water Initially Encountered Auger Cuttings Modified Dames & Moore Ring Sampler Standard Penetration Test Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracy of such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey was conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic maps of the area. Standard Penetration Test Resistance (Blows/Ft.) Hand Penetrometer Torvane Dynamic Cone Penetrometer Photo-Ionization Detector Organic Vapor Analyzer STRENGTH TERMS Standard Penetration or N-Value Blows/Ft. Descriptive Term (Consistency) Descriptive Term (Density) CONSISTENCY OF FINE-GRAINED SOILS (50% or more passing the No. 200 sieve.) Consistency determined by laboratory shear strength testing, field visual-manual procedures or standard penetration resistance Standard Penetration or N-Value Blows/Ft. (More than 50% retained on No. 200 sieve.) Density determined by Standard Penetration Resistance RELATIVE DENSITY OF COARSE-GRAINED SOILS Hard > 30 > 50 Very Stiff 15 - 30 Stiff Medium Stiff Very Soft 0 - 1 Medium Dense Loose Soft Very Dense Dense 30 - 50 8 - 15 10 - 29 4 - 8 4 - 9 2 - 4 Very Loose 0 - 3 87.5 85.1 %Fines LL PL PI 4 1 3/4 1/2 60 fine 1 3 4 6 7 8.03 GRAIN SIZE IN MILLIMETERS PERCENT FINER BY WEIGHT coarse fine U.HYDROMETERS. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS 20 18 NP 17 17 7 7 NP 21 14 0.93 D100 Cc Cu SILT OR CLAY 4 D30 D10 %Gravel %Sand 4 - 5 4 - 5 14 - 14.9 4 - 5.5 4 - 5 3/8 3 100 3 140 2 COBBLES GRAVEL SAND USCS Classification 28.5 38.8 69.5 12.4 14.0 D60 coarse medium Boring ID Depth Boring ID Depth GRAIN SIZE DISTRIBUTION 4 - 5 4 - 5 14 - 14.9 4 - 5.5 4 - 5 SILTY CLAY with SAND (CL-ML) SANDY SILTY CLAY (CL-ML) POORLY GRADED SAND with GRAVEL (SP) LEAN CLAY (CL) LEAN CLAY (CL) ASTM D422 / ASTM C136 PROJECT NUMBER: 20165074 PROJECT: BETCO Self-Storage SITE: Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado CLIENT: Hauser Architects PC Loveland, Colorado EXHIBIT: B-3 1901 Sharp Point Dr Ste C Fort Collins, CO LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 20165074.GPJ 35159097 - ATTERBERG ISSUE.GPJ 8/24/16 85 LL USCS 1 3 4 6 7 ATTERBERG LIMITS RESULTS ASTM D4318 4 - 5 4 - 5 14 - 14.9 4 - 5.5 4 - 5 PROJECT NUMBER: 20165074 PROJECT: BETCO Self-Storage SITE: Northeast of Conifer Street and Red Cedar Circle Fort Collins, Colorado CLIENT: Hauser Architects PC Loveland, Colorado EXHIBIT: B-2 1901 Sharp Point Dr Ste C Fort Collins, CO LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. ATTERBERG LIMITS 20165074.GPJ TERRACON2015.GDT 8/24/16 CL-ML DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 98.19 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60305° Longitude: -105.073° See Exhibit A-2 9' while drilling 7.8' on 8/22/2-16 WATER LEVEL OBSERVATIONS DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 99.37 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60328° Longitude: -105.07323° See Exhibit A-2 9.5' while drilling 6' on 8/22/2016 WATER LEVEL OBSERVATIONS See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 96.6 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 20 25 30 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60295° Longitude: -105.07343° See Exhibit A-2 8' while drilling WATER LEVEL OBSERVATIONS Driller: Drilling Engineers, Inc. Boring Completed: 8/11/2016 Exhibit: A-7 See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 99.57 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 20 25 30 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60378° Longitude: -105.07336° See Exhibit A-2 9' while drilling WATER LEVEL OBSERVATIONS procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 100.2 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 20 25 30 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60346° Longitude: -105.0741° See Exhibit A-2 9' while drilling WATER LEVEL OBSERVATIONS See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 100.48 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 20 25 30 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60384° Longitude: -105.07436° See Exhibit A-2 10' while drilling WATER LEVEL OBSERVATIONS See Exhibit A-3 for description of field procedures. See Appendix B for description of laboratory procedures and additional data (if any). See Appendix C for explanation of symbols and abbreviations. PROJECT: BETCO Self-Storage UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI Surface Elev.: 98.09 (Ft.) ELEVATION (Ft.) SAMPLE TYPE WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 15 20 25 30 SWELL - CONSOL / LOAD (%/psf) FIELD TEST RESULTS DEPTH LOCATION Latitude: 40.60298° Longitude: -105.07437° See Exhibit A-2 7' while drilling WATER LEVEL OBSERVATIONS granular backfill, an equivalent fluid weighing 85 and 90 pcf should be used for active and at-rest, respectively. These pressures do not include the influence of surcharge, equipment or floor loading, which should be added. Heavy equipment should not operate within a distance closer than the exposed height of retaining walls to prevent lateral pressures more than those provided. 4.8 Pavements 4.8.1 Pavements – Subgrade Preparation On most project sites, the site grading is accomplished relatively early in the construction phase. Fills are typically placed and compacted in a uniform manner. However as construction proceeds, the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, or rainfall/snow melt. As a result, the pavement subgrade may not be suitable for pavement construction and corrective action will be required. The subgrade should be carefully evaluated at the time of pavement construction for signs of disturbance or instability. We recommend the pavement subgrade be thoroughly proofrolled with a loaded tandem-axle dump truck prior to final