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Home My WebLink AboutPOUDRE VALLEY HOSPITAL A-WING REPLACEMENT - PDP - PDP140019 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTGeotechnical Engineering Report UCH Building A and Parking Lot 1024 South Lemay Avenue Fort Collins, Colorado September 19, 2014 Terracon Project No. 20135044 Prepared for: Aspen Engineering Fort Collins, Colorado Prepared by: Terracon Consultants, Inc. Fort Collins, Colorado TABLE OF CONTENTS Page EXECUTIVE SUMMARY ............................................................................................................ i 1.0 INTRODUCTION ............................................................................................................ 1 2.0 PROJECT INFORMATION ............................................................................................ 2 2.1 Project Description .............................................................................................. 2 2.2 Site Location and Description ............................................................................. 3 3.0 SUBSURFACE CONDITIONS ....................................................................................... 3 3.1 Typical Subsurface Profile .................................................................................. 3 3.2 Laboratory Testing .............................................................................................. 4 3.3 Groundwater ....................................................................................................... 4 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ..................................... 5 4.1 Geotechnical Considerations .............................................................................. 5 4.1.1 Existing, Undocumented Fill .................................................................... 5 4.1.2 Groundwater ............................................................................................ 5 4.1.3 Expansive Soils ....................................................................................... 6 4.1.4 Foundation Recommendations ................................................................ 6 4.2 Earthwork ........................................................................................................... 6 4.2.1 Site Preparation........................................................................................ 6 4.2.2 Demolition ............................................................................................... 7 4.2.3 Excavation ............................................................................................... 7 4.2.4 Subgrade Preparation .............................................................................. 8 4.2.5 Fill Materials and Placement ..................................................................... 9 4.2.6 Compaction Requirements ......................................................................10 4.2.7 Utility Trench Backfill ..............................................................................10 4.2.8 Grading and Drainage .............................................................................11 4.2.9 Exterior Slab Design and Construction ...................................................12 4.2.10 Corrosion Protection ...............................................................................12 4.3 Foundations .......................................................................................................12 4.3.1 Drilled Piers Bottomed in Bedrock - Design Recommendations ..............12 4.3.2 Drilled Piers Bottomed in Bedrock - Construction Considerations ...........13 4.3.3 Helical Pile Foundations .........................................................................14 4.3.4 Basement Construction ..........................................................................15 4.4 Seismic Considerations......................................................................................15 4.5 Floor Systems ....................................................................................................15 4.5.1 Floor System - Design Recommendations ..............................................16 4.5.2 Floor Systems - Construction Considerations .........................................17 4.6 Lateral Earth Pressures .....................................................................................17 4.7 Pavements .........................................................................................................18 4.7.1 Pavements – Subgrade Preparation .......................................................18 4.7.2 Pavements – Design Recommendations ................................................19 4.7.3 Pavements – Construction Considerations .............................................21 4.7.4 Pavements – Maintenance .....................................................................22 5.0 GENERAL COMMENTS ...............................................................................................22 TABLE OF CONTENTS (continued) Appendix A – FIELD EXPLORATION Exhibit A-1 Site Location Map Exhibit A-2 Exploration Plan Exhibit A-3 Boring Location Plan Exhibit A-4 Field Exploration Description Exhibits A-5 to A-13 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 to B-7 Swell-consolidation Test Results Exhibit B-8 Corrosion 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 UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable i EXECUTIVE SUMMARY A geotechnical investigation has been performed for the proposed University of Colorado Hospital (UCH) – Poudre Valley Hospital Building A and new parking Lot to be constructed at 1024 South Lemay Avenue in Fort Collins, Colorado. Six (6) borings, presented as Exhibits A-5 through A-13 and designated as Boring No. 1 through Boring No. P3, were performed to depths of approximately 10 to 39 feet below existing site grades. This report specifically addresses the recommendations for the proposed Building A and parking lot. 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:  Existing, undocumented fill was encountered in the borings performed on this site to depths ranging from about 2 to 8 feet below existing site grades. Subgrade soils below pavements should be scarified a minimum of 8 inches, moisture conditioned, and compacted to 95 percent of the maximum dry density as determined by ASTM D698.  The proposed Building A reconstruction may be supported on a drilled pier foundation system bottomed in bedrock.  A slab-on-grade floor system is recommended for the proposed Building A provided the subgrade below the basement floor slab is over-excavated a minimum of 2 feet, moisture conditioned and recompacted. The upper 12 inch of over-excavation backfill below the slab should consist of imported CDOT Class 1 structure backfill.  The amount of movement of pavements will be related to the wetting of underlying supporting soils. Therefore, it is imperative the recommendations 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 UCH Building A and Parking Lot 1024 South Lemay Avenue Fort Collins, Colorado Terracon Project No. 20135044 September 19, 2014 1.0 INTRODUCTION This report presents the results of our geotechnical engineering services performed for the proposed UCH Building A reconstruction and Parking Lot located at 1024 South Lemay Avenue in Fort Collins, Colorado. 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 six (6) test borings to depths ranging from approximately 10 to 39 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) and Boring Location Plan (Exhibit A-3) 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. Previously, Terracon prepared several Geotechnical Engineering Reports during various stages of development at this facility including, but not limited to, the following: ■ Geotechnical Engineering Report for proposed addition and remodeling(Project No. 4818-82; reports dated July 29, 1982, updated June 22, 1984); ■ Geotechnical Engineering Report (Project No. 5125-83; report dated September 19, 1984); ■ Geotechnical Engineering Report (Project No. 8058-89; report dated July 21, 1989); ■ Geotechnical Engineering Report for parking area (Project No. 20055221; report dated January 5, 2006); Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 2 ■ Geotechnical Engineering Report for OR addition (Project No. 20065159, report dated November 7, 2006); ■ Geotechnical Engineering Report for the parking garage expansion (Project No. 20065163, report dated November 30, 2006); and ■ Geotechnical Engineering Report for a medical office building (Project No. 20075039, report dated May 14, 2007). 2.0 PROJECT INFORMATION 2.1 Project Description Item Description Site layout Refer to the Exploration Plan (Exhibit A-2 in Appendix A) Proposed construction (Building A) The original Building A, constructed in 1925, was a stand-alone hospital that eventually developed into a wing of the main Poudre Valley Hospital, which is now 700,000 square feet in size. Due to Building A’s age and other factors affecting the useful life of the building, the Owner has elected to vacate the building and relocate all staff and occupants, abate existing asbestos, and demolish the building. A new Building A project is being planned and includes a basement supporting a two-story, approximately 111,200 square foot structure with a full basement and capacity to add two additional levels in the future. Proposed construction (New Parking Lot) We understand three of the medical office buildings occupying the site located north of Doctors Lane, between Hospital Lane and Luke Street will be demolished and razed from the site. Existing civil improvements including pavements, curb, gutter, sidewalks, landscaping, etc. will also be removed from this site to prepare for construction of a new parking lot. Finished floor elevation We anticipate the finished floor elevation for the new Building A will match existing building floor elevations. A full-depth basement is also planned for the proposed addition. Maximum loads We will collaborate with the design team to understand expected foundation and floor loads for the proposed Building A. Grading We anticipate cuts and fills on the order of 5 to 10 feet will be necessary for demolition and site preparation. Deeper cuts and fills on the order of 12 to 15 feet will be required for basement and utility construction. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 3 2.2 Site Location and Description Item Description Location Building A of the University of Colorado Hospital – Poudre Valley Hospital is located on the north side of the existing facility at 1024 South Lemay Avenue in Fort Collins, Colorado. The proposed parking lot site is located north of Doctors Lane, between Hospital Lane and Luke Street, north of the hospital. Existing improvements A portion of the existing “A-wing” of the hospital currently occupies the proposed addition site with the remainder of the hospital facility to the south, parking and hospital buildings to the east, and South Lemay Avenue and the parking garage to the west. The existing hospital buildings adjacent to the Building A reconstruction have multiple finished floor elevations and full-depth basements. Partial demolition of the existing “A-wing” has been completed at the time we completed this study, particularly interior finishes. Existing medical office buildings and paved parking and drive lanes occupy the proposed parking lot site. Current ground cover The ground surface is covered by existing buildings, asphalt pavement, concrete flatwork, and irrigated grass and landscape. Existing topography The sites are 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: Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 4 Material Description Approximate Depth to Bottom of Stratum (feet) Consistency/Density/Hardness Fill materials consisting of lean clay, sand, and gravel About 2 to 8 feet below existing site grades. -- Silty sand About 10 feet below existing asphalt pavement in Boring Nos. P1 through P3 only. Very loose to loose Lean clay with varying amounts of sand About 14 to 26 feet below existing site grades. Medium stiff to very stiff Sand with varying amounts of silt, clay, cobbles, and gravel About 30½ to 35 feet below existing site grades. Medium dense to very dense Shale To the maximum depth of exploration of about 39 feet. Medium hard to very hard 3.2 Laboratory Testing Representative soil samples were selected for swell-consolidation testing and exhibited 1.0 to 3.6 percent compression when wetted. Samples of site soils and bedrock selected for plasticity testing exhibited non-plastic to medium plasticity with liquid limits ranging from non-plastic to 34 and plasticity indices ranging from 7 to 18. Laboratory test results are presented in Appendix B. 3.3 Groundwater The boreholes were observed while drilling and after completion for the presence and level of groundwater. In addition, delayed water levels were also obtained in some 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 4 days after drilling, ft. Elevation of groundwater 4 days after drilling, ft. 1 27 25.2 75.3 2 27 26.4 73.6 3 26 24.4 75.0 P1 Not encountered Backfilled after drilling Backfilled after drilling P2 Not encountered Backfilled after drilling Backfilled after drilling P3 Not encountered Backfilled after drilling Backfilled after drilling These observations represent groundwater conditions at the time of the field exploration, 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, and other factors. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 5 Groundwater level fluctuations occur due to seasonal variations in the 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 structure 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 sufficient 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 structure, floor slabs, pavements, and other site improvements. 4.1.1 Existing, Undocumented Fill As previously noted, existing undocumented fill was encountered to depths up to about 8 feet in the borings drilled at the site. We do not possess any information regarding whether the fill was placed under the observation of a geotechnical engineer. However, we believe the fill was likely placed during construction of the hospital. Support of floor slabs and pavements on or above existing fill soils is discussed in this report. However, even with the recommended construction testing services, there is an inherent risk for the owner that compressible fill or unsuitable material within or buried by the fill will not be discovered. This risk of unforeseen conditions cannot be eliminated without completely removing the existing fill, but can be reduced by performing additional testing and evaluation. 4.1.2 Groundwater As previously stated, groundwater was measured at depths ranging from about 25 to 26 feet below existing site grades. We understand a full depth basement is planned at this site. 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. However, we do not believe groundwater will significantly impact the proposed construction at this site except drilled pier construction. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 6 4.1.3 Expansive Soils Laboratory testing indicates the native clay soils exhibited 1.0 to 3.6 percent compression upon wetting at the samples in-situ moisture content. However, it is our experience these materials will exhibit a higher expansive potential if the clays undergo a significant loss of moisture. 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 The proposed building reconstruction may be supported on a drilled pier foundation system bottomed in bedrock. We recommend a slab-on-grade for the interior floor system of the proposed building reconstruction provided the subgrade below the basement floor slab is over- excavated a minimum of 2 feet, moisture conditioned and recompacted. The upper 12 inches of backfill below the floor slab should consist of imported, Colorado Department of Transportation (CDOT) Class 1 structure backfill.. 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. 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 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. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 7 4.2.2 Demolition Demolition of the existing Building A and parking lot site 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 materials derived from the demolition of existing structures and pavements should be removed from the site. The types of foundation systems supporting the existing Building A and medical office buildings are not known. If some or all of the existing buildings are supported by drilled piers, the existing piers should be truncated a minimum depth of 3 feet below areas of planned new construction. 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. 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 underground facilities such as septic tanks, vaults, and basements 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 existing building foundations that are exposed during the excavations for the Building A reconstruction should be examined and evaluated by Terracon to determine the need for any shoring or underpinning. Excavations should not extend into the stress influence zone of the existing foundations without prior evaluation by Terracon. The stress influence zone is defined as the area below a line projected down at a 1(h) to 1(v) slope from the bottom edge of the existing foundation. Excavations within the influence zone of existing foundations can result in loss of support, and can create settlement or failure of the existing foundations. While the evaluation of existing foundations and the design of a shoring system are beyond the scope of this study, we can perform these tasks as a separate study. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 8 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. If any excavation, including a utility trench, is extended to a depth of more than 20 feet, it will be necessary to have the side slopes and/or shoring system designed by a professional engineer. 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 After the minimum 2 feet of over-excavation below the Building A floor slabs and any other deleterious materials been removed from the construction areas, the top 8 inches of the exposed ground surface should be scarified, moisture conditioned, and recompacted to at least 95 percent of the maximum dry unit weight as determined by ASTM D698 before any new fill, foundation, or pavement is placed. If pockets of soft, loose, or otherwise unsuitable materials are encountered at the bottom of the floor slab excavations, the proposed floor slab elevations may be reestablished by over- excavating the unsuitable soils and backfilling with compacted engineered fill or lean concrete. Any over-excavation should be performed in accordance with the excavation recommendations given in this report. After the bottom of the excavation has been compacted, engineered fill can be placed to bring the floor slab and pavement subgrade to the desired grade. Engineered fill should be placed in accordance with the recommendations presented in subsequent sections of this report. 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 lime, fly ash, cement or geotextiles could also be considered as a stabilization technique. Lightweight excavation equipment may also be used to reduce subgrade pumping. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 9 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 on-site fill. It should be noted that on-site soils will 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 15-50 Soil Properties Value Liquid Limit 30 (max.) Plastic Limit 15 (max.) 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. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 10 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 Total fill thickness of 8 feet or less: 95 percent of the maximum dry unit weight as determined by ASTM D698 Total fill thickness greater than 8 feet in thickness: 98 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 +2 % 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 structure 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. Utility trenches are a common source of water infiltration and migration. All utility trenches that penetrate beneath the building should be effectively sealed to restrict water intrusion and flow Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 11 through the trenches that could migrate below the building. We recommend constructing an effective clay “trench plug” that extends at least 5 feet out from the face of the building exterior. 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 building reconstruction, existing buildings, and proposed pavements 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 structure (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 building reconstruction, 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 building. Backfill against exterior walls should be properly compacted and free of all construction debris to reduce the possibility of moisture infiltration. After construction of the proposed building 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 structure, care should be taken that joints are properly sealed and maintained to prevent the infiltration of surface water. Planters located adjacent to the structure 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 UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 12 4.2.9 Exterior Slab Design and Construction Exterior slabs on-grade, exterior architectural features, and utilities founded on, or in backfill or the site soils will likely experience some movement due to the volume change of the material. Potential movement could be reduced by:  Minimizing moisture increases in the backfill;  Controlling moisture-density during placement of the backfill;  Using designs which allow vertical movement between the exterior features and adjoining structural elements; and  Placing control joints on relatively close centers. 4.2.10 Corrosion Protection Results of water-soluble sulfate testing indicate that ASTM Type I or II portland cement should be specified for all project concrete on and below grade. Foundation concrete should be designed for low sulfate exposure in accordance with the provisions of the ACI Design Manual, Section 318, Chapter 4. 4.3 Foundations The proposed building can be supported by a drilled pier foundation system bottomed in bedrock. Helical piles bottomed in bedrock are also considered a suitable foundation alternative for limited access locations. Design recommendations for foundations for the proposed structure and related structural elements are presented in the following paragraphs. 4.3.1 Drilled Piers Bottomed in Bedrock - Design Recommendations Description Value Minimum pier diameter 18 inches Minimum bedrock embedment 1 10 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. 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. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 13 To satisfy forces in the horizontal direction using LPILE, piers may be designed for the following lateral load criteria: Parameters Clay Sand and Gravel Sand and Gravel Shale Bedrock LPILE soil type1 Stiff clay without free water Sand (above WT) Sand (submerged) Stiff clay without free water Unit weight (pcf) 120 125 65 130 Average undrained shear strength (psf) 500 N/A N/A 9,000 Average angle of internal friction,  (degrees) N/A 35 35 N/A Coefficient of subgrade reaction, k (pci)* 100 - static 30 - cyclic 90 60 2,000- static 800 – cyclic Strain, 50 (%) 0.010 N/A N/A 0.004 1. For purposes of LPILE analysis, assume a groundwater depth of about 25 feet below existing ground surface. 4.3.2 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. In addition, caving soils and groundwater indicate that temporary steel casing will be required to properly drill the 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. 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 shale bearing strata. This should be accomplished by a roughening tooth placed on the auger. Shaft bearing Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 14 surfaces must be cleaned prior to concrete placement. A representative of Terracon should observe the bearing surface and shaft configuration. 4.3.3 Helical Pile Foundations We believe helical piles bottomed in bedrock are an appropriate alternative for support of the proposed Building A reconstruction. Design recommendations for helical pile foundations and related structural elements are presented in the following paragraphs. Description Value Bearing material Shale bedrock Anticipated pile length About 15 to 40 feet from existing site grades Net allowable end-bearing pressure 1 25,000 psf Individual pile settlement About ½ inch Void thickness (between piles and below pile caps) 4 inches 1. The design bearing pressure applies to dead loads plus design live load conditions. The design bearing pressure may be increased by one-third when considering total loads that include wind or seismic conditions. We do not recommend using vertically installed helical piles to resist lateral loads without approved lateral load test data, as these types of foundations are typically designed to resist axial loads. Only the horizontal component of the allowable axial load should be considered to resist the lateral loading and only in the direction of the batter. Terracon should be retained to observe helical pile installation to verify that proper bearing materials have been encountered during installation. If a helical pile foundation system is selected by the project team, we recommend the helical pile designer follow the recommendations presented in Chapter 18 of the 2009/2012 International Building Code (IBC). We recommend the helical bearing plates for each helical pile bear in the shale bedrock encountered below the site. We do not recommend helical bearing plates bottomed in native clay soils. The helical pile designer should select the size and number of helical bearing plates for each helical pile based on planned loads and bearing materials described in our exploratory boring logs. Torque measurements during installation of helical piles should be used to verify the axial capacity of the helical piles. We recommend the helical pile installation contractor provide confirmation that the installation equipment has been calibrated within one year of installation at this project. The helical foundations should be installed per the manufacturer’s recommendations. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 15 4.3.4 Basement Construction Groundwater was encountered at depths ranging from 25 to 26 feet below existing site grades. We do not believe groundwater will significantly affect the proposed full-depth basement. To reduce the potential for surface water to impact foundation bearing soils and enter the basement of the building, installation of a perimeter drainage system is recommended. The drainage system should be constructed around the exterior perimeter of the basement foundation, and sloped at a minimum 1/8 inch per foot to a suitable outlet, such as a sump and pump system. The drainage system should consist of a properly sized perforated pipe, embedded in free- draining gravel, placed in a trench at least 12 inches in width. Gravel should extend at least 2 feet above the bottom of the foundation wall. The system should be underlain with a polyethylene moisture barrier, sealed to the foundation walls, and extended at least to the edge of the backfill zone. The gravel should be covered with drainage fabric prior to placement of foundation backfill. 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 39 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 Building A reconstruction provided the subgrade below the basement floor slab is over-excavated a minimum of 2 feet, moisture conditioned and recompacted. The upper 12 inches of backfill below the slab should consist of imported CDOT Class 1 Structure backfill. If very little movement can be tolerated, a structurally-supported floor system, supported independent of the subgrade materials, is recommended. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 16 Subgrade soils beneath interior and exterior slabs and at the base of the over-excavation should be scarified to a depth of at least 8 inches, moisture conditioned and compacted. The moisture content and compaction of subgrade soils should be maintained until slab construction. 4.5.1 Floor System - Design Recommendations 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. If conventional slab-on-grade is utilized, the subgrade soils should be over-excavated and prepared as outlined in the 4.2 Earthwork section of this report. For structural design of concrete slabs-on-grade subjected to point loadings, a modulus of subgrade reaction of 100 pounds per cubic inch (pci) may be used for floors supported on re- compacted existing soils at the site. A modulus of 200 pci may be used for floors supported on at least 1 foot of non-expansive, imported granular fill. Additional floor slab design and construction recommendations are as follows:  Positive separations and/or isolation joints should be provided between slabs and all foundations, columns, or utility lines to allow independent movement.  Control joints should be saw-cut in slabs in accordance with ACI Design Manual, Section 302.1R-37 8.3.12 (tooled control joints are not recommended) to control the location and extent of cracking.  Interior utility trench backfill placed beneath slabs should be compacted in accordance with the recommendations presented in the 4.2 Earthwork section of this report.  Floor slabs should not be constructed on frozen subgrade.  A minimum 2-inch void space should be constructed below non-bearing partition walls placed on the floor slab. Special framing details should be provided at doorjambs and frames within partition walls to avoid potential distortion. Partition walls should be isolated from suspended ceilings.  The use of a vapor retarder should be considered beneath concrete slabs that will be covered with wood, tile, carpet or other moisture sensitive or impervious floor coverings, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer and slab contractor should refer to ACI 302 for procedures and cautions regarding the use and placement of a vapor retarder. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 17  Other design and construction considerations, as outlined in the ACI Design Manual, Section 302.1R are recommended. 4.5.2 Floor Systems - Construction Considerations Movements of slabs-on-grade using the recommendations discussed in previous sections of this report will likely be reduced and tend to be more uniform. The estimates discussed above assume that the other recommendations in this report are followed. Additional movement could occur should the subsurface soils become wetted to significant depths, which could result in potential excessive movement causing uneven floor slabs and severe cracking. This could be due to over watering of landscaping, poor drainage, improperly functioning drain systems, and/or broken utility lines. Therefore, it is imperative that the recommendations presented in this report be followed. 4.6 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. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 18 EARTH PRESSURE COEFFICIENTS Earth Pressure Conditions Coefficient for Backfill Type Equivalent Fluid Density (pcf) Surcharge Pressure, p1 (psf) Earth Pressure, p2 (psf) Active (Ka) Granular Material - 0.27 Lean Clay - 0.41 35 49 (0.27)S (0.41)S (35)H (49)H At-Rest (Ko) Granular Material - 0.43 Lean Clay - 0.58 56 70 (0.46)S (0.58)S (56)H (70)H Passive (Kp) Granular Material - 3.69 Lean Clay - 2.46 480 295 --- --- --- --- 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 Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 19 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 grading and paving. All pavement areas should be moisture conditioned and properly compacted to the recommendations in this report immediately prior to paving. 4.7.2 Pavements – Design Recommendations Design of pavements for the project have been based on the procedures outlined in the 1993 Guideline for Design of Pavement Structures prepared by the American Association of State Highway and Transportation Officials (AASHTO) and the Larimer County Urban Area Street Standards (LCUASS). Samples of the site soils selected for swell-consolidation testing swelled less than the maximum 2 percent criteria established for determining if swell-mitigation procedures in the pavement sections are required per LCUASS standards. Therefore, swell-mitigation of the subgrade materials prior to pavement operations is not required. Traffic patterns and anticipated loading conditions were not available at the time that this report was prepared. However, we anticipate that the new parking areas (i.e., light-duty) will be primarily used by personal vehicles (cars and pick-up trucks). Delivery trucks and refuse disposal vehicles will be expected in the drive lanes and loading areas (i.e., medium-duty). For our pavement thicknesses design recommendations, we assumed a 18-kip equivalent single- axle load (ESAL) of 73,000 for automobile parking areas and an ESAL of 365,000 for heavy truck traffic areas. These assumed traffic design values should be verified by the civil engineer or owner prior to final design and construction. If the actual traffic values vary from the assumed values, the pavement thickness recommendations may not be applicable. When the actual traffic design information is available Terracon should be contacted so that the design recommendations can be reviewed and revised if necessary. For flexible pavement design, a terminal serviceability index of 2.0 was utilized along with an inherent reliability of 85 percent and a design life of 20 years. Using the correlated design R-value of 35, appropriate ESAL, environmental criteria and other factors, the structural numbers (SN) of the pavement sections were determined on the basis of the 1993 AASHTO design equation. In addition to the flexible pavement design analyses, a rigid pavement design analysis was completed based upon AASHTO design procedures. Rigid pavement design is based on an evaluation of the Modulus of Subgrade Reaction of the soils (k-value), the Modulus of Rupture of the concrete, and other factors previously outlined. The design k-value of 155 for the subgrade soil was determined by correlation to the laboratory test results. A modulus of rupture of 600 psi (working stress 450 psi) was used for pavement concrete. The rigid pavement thickness for each traffic category was determined on the basis of the AASHTO design equation. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 20 Recommended minimum pavement sections are provided in the table below. Traffic Area Alternative Recommended Pavement Thicknesses (Inches) Asphaltic Concrete Surface Aggregate Base Course Portland Cement Concrete Total Automobile parking areas (light-duty) A 4 6 -- 10 B -- -- 5 5 Heavy truck traffic areas (heavy-duty) A 5 8 -- 12 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 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 type Type I or II portland cement Entrained air content (%) 5 to 8 Concrete aggregate ASTM C33 and CDOT Section 703 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. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 21 The location and extent of joints should be based upon the final pavement geometry. Joints should be sealed to prevent entry of foreign material and doweled where necessary for load transfer. 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 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. 4.7.3 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. Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable 22 4.7.4 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 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 SITE LOCATION MAP UCH Building A and Parking Lot 1024 South Lemay Avenue Fort Collins, CO TOPOGRAPHIC MAP IMAGE COURTESY OF THE U.S. GEOLOGICAL SURVEY QUADRANGLES INCLUDE: FORT COLLINS, CO (1/1/1984). 1901 Sharp Point Dr Suite C Ft. Collins, CO 20135044 Project Manager: Drawn by: Checked by: Approved by: BCR EDB B EDB 1:24,000 9/11/2014 Project No. Scale: File Name: Date: A-1 EDB Exhibit EXPLORATION PLAN UCH Building A and Parking Lot 1024 South Lemay Avenue Fort Collins, CO 1901 Sharp Point Dr Suite C Ft. Collins, CO DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES 20135044 AERIAL PHOTOGRAPHY PROVIDED BY MICROSOFT BING MAPS BCR EDB EDB AS SHOWN 9/11/2014 Scale: A-2 Project Manager: Exhibit Drawn by: Checked by: Approved by: Project No. File Name: Date: EDB Legend Approximate Location of Temporary Benchmark (Top of concrete slab assumed elevation 100.0’) Approximate Boring Location 0’ 50’ 100’ APPROXIMATE SCALE Scale: EDB EDB JCG EDB Project Manager: Drawn by: Checked by: Approved by: BORING LOCATION PLAN UCH Building A and Parking Lot 1024 South Lemay Avenue Fort Collins, Colorado A-3 20135044 Exhibit 9/11/2014 1=100’ Project No. File Name: Date: DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 1984 (PROJECT NO. 5125-83; REPORT DATED 9/12/84) LEGEND APPROXIMATE LOCATION OF TEMPORARY BENCHMARK (TOP OF CONCRETE SLAB – ASSUMED ELEVATION 100.0’) 1 1 1901 Sharp Point Drive, Suite C Fort Collins, Colorado 80525 PH. (970) 484-0359 FAX. (970) 484-0454 Approximate Location of New Building A Approximate Location of New Parking Lot APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 2005 (PROJECT NO. 20055221; REPORT DATED 1/5/06) 1 4 1 2 1 APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 1982 & 1984 (PROJECT NO. 4818-82; REPORTS DATED 7/29/82, UPDATED 6/22/84) 12 11 15 14 Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 Responsive ■ Resourceful ■ Reliable Exhibit A-4 Field Exploration Description The locations of borings were based upon discussions with the project team reguarding the proposed construction. 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 Exhibits A-2 and A-3 using an engineer’s level. The borings were drilled with CME-55 and CME-75 truck-mounted rotary drill rigs 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. 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. 0.8 14.0 24.0 TOPSOIL / VEGETATION LEAN CLAY WITH SAND (CL), brown, medium stiff to stiff SANDY LEAN CLAY (CL), brown and reddish-brown, medium stiff to very stiff CLAYEY SAND, brown, medium dense, interbedded with well graded sand 2-3-5 N=8 3-3 4-4 3-5-8 N=13 2-3-2 N=5 7-7-9 N=16 0.004 15 11 11 13 17 14 103 99 34-18-16 32-17-15 32-14-18 98.5 85.5 75.5 -3.6 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.572742° Longitude: -105.057554° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 1 of 2 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-75 Boring Started: 8/25/2014 BORING LOG NO. 1 CLIENT: Aspen Engineering Fort Collins, Colorado 29.0 30.5 39.3 CLAYEY SAND, brown, medium dense, interbedded with well graded sand (continued) WELL GRADED SAND WITH SILT AND GRAVEL, trace cobbles, fine to coarse grained, brown, very dense SEDIMENTARY BEDROCK - SHALE, gray, very hard Boring Terminated at 39.3 Feet 13-26-26 N=52 24-29 50/3" 14 39 70.5 69 60 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.572742° Longitude: -105.057554° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 2 of 2 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-75 Boring Started: 8/25/2014 BORING LOG NO. 1 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Terracon Boring Completed: 8/25/2014 Exhibit: A-6 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG 0.8 8.0 16.0 24.5 TOPSOIL / VEGETATION FILL - LEAN CLAY WITH SAND , brown to light brown, medium stiff to stiff LEAN CLAY WITH SAND (CL), brown to light brown, medium stiff to stiff SANDY LEAN CLAY, light red brown, medium stiff to stiff WELL GRADED SAND WITH GRAVEL, trace cobbles, fine to coarse grained, brown and reddish-brown, very dense 1-3-5 N=8 2-3 2-3 2-2-3 N=5 3-5-6 N=11 15-33-33 N=66 0.008 3 12 18 2 99 30-22-8 99 91.5 83.5 75 -1.4 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.572771° Longitude: -105.057071° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 1 of 2 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-75 Boring Started: 8/25/2014 BORING LOG NO. 2 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Terracon Boring Completed: 8/25/2014 32.0 39.3 WELL GRADED SAND WITH GRAVEL, trace cobbles, fine to coarse grained, brown and reddish-brown, very dense (continued) SEDIMENTARY BEDROCK - SHALE, gray, medium hard to hard Boring Terminated at 39.3 Feet 9-24 18-28-50 N=78 50/4" 6 16 16 67.5 60.5 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.572771° Longitude: -105.057071° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 2 of 2 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-75 Boring Started: 8/25/2014 BORING LOG NO. 2 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Terracon Boring Completed: 8/25/2014 Exhibit: A-8 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS 0.8 4.0 5.0 22.0 26.0 TOPSOIL / VEGETATION FILL - SANDY LEAN CLAY , brown, medium stiff FILL - WELL GRADED SAND WITH GRAVEL , fine to coarse grained, dark brown, medium dense SANDY LEAN CLAY (CL), brown and reddish-brown, stiff to very stiff LEAN CLAY WITH INTERBEDDED WELL GRADED SAND, brown and reddish-brown, stiff 1-3-5 N=8 3-7 6-6 6-8-9 N=17 2-4-5 N=9 7-8-4 N=12 14 5 14 13 21 23 103 84 31-13-18 99.5 96 95 78 74 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.572381° Longitude: -105.057616° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 1 of 2 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-75 Boring Started: 8/25/2014 BORING LOG NO. 3 CLIENT: Aspen Engineering 35.0 39.4 WELL GRADED SAND WITH GRAVEL, fine to coarse grained, red brown, medium dense (continued) SEDIMENTARY BEDROCK - SHALE, trace sand, gray, medium hard to very hard Boring Terminated at 39.4 Feet 4-9-8 N=17 8-12-35 N=47 50/5" 8 15 16 65 60.5 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.572381° Longitude: -105.057616° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 2 of 2 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-75 Boring Started: 8/25/2014 BORING LOG NO. 3 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Terracon Boring Completed: 8/25/2014 Exhibit: A-10 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS 0.3 10.0 ASPHALT PAVEEMNT - 3 inches SILTY SAND (SM), fine to medium grained, brown, very loose to loose Boring Terminated at 10 Feet 4-4 3-3 3-4 9 6 9 105 105 -1.0 NP Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.573553° Longitude: -105.056849° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-55 Boring Started: 8/22/2014 BORING LOG NO. P1 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/22/2014 Exhibit: A-11 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI ELEVATION (Ft.) 0.3 10.0 ASPHALT PAVEEMNT - 3 inches SILTY SAND, trace gravel, fine to medium grained, brown to reddish-brown, very loose to loose Boring Terminated at 10 Feet 3-4 4-3 3-3 13 12 9 105 109 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.573256° Longitude: -105.056584° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-55 Boring Started: 8/22/2014 BORING LOG NO. P2 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/22/2014 Exhibit: A-12 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI ELEVATION (Ft.) DEPTH (Ft.) 0.2 4.0 10.0 ASPHALT PAVEMENT - 2 inches SANDY SILTY CLAY (CL-ML), brown, soft SILTY SAND, fine to coarse grained, brown to reddish-brown, loose Boring Terminated at 10 Feet 3-3 4-4 3-6 0.002 10 14 9 93 102 89 -2.9 27-20-7 Stratification lines are approximate. In-situ, the transition may be gradual. Hammer Type: Automatic LOCATION DEPTH Latitude: 40.57314° Longitude: -105.055956° GRAPHIC LOG See Exhibit A-2 THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL 20135044.GPJ TEMPLATE UPDATE 3-31-14.GPJ 9/19/14 1024 South Lemay Avenue Fort Collins, Colorado SITE: Page 1 of 1 Advancement Method: 4 inch solid-stem augers Abandonment Method: Borings backfilled with soil cuttings upon completion. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado Notes: Project No.: 20135044 Drill Rig: CME-55 Boring Started: 8/22/2014 BORING LOG NO. P3 CLIENT: Aspen Engineering Fort Collins, Colorado Driller: Drilling Engineers, Inc. Boring Completed: 8/22/2014 Exhibit: A-13 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) APPENDIX B LABORATORY TESTING Geotechnical Engineering Report UCH Building A and Parking Lot ■ Fort Collins, Colorado September 19, 2014 ■ Terracon Project No. 20135044 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  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 PL PI 2.0 9.0 14.0 9.0 14.0 2.0 2.0 Boring ID Depth Description LEAN CLAY with SAND LEAN CLAY with SAND SANDY LEAN CLAY LEAN CLAY with SAND SANDY LEAN CLAY SILTY SAND SANDY SILTY CLAY CL CL CL CL CL SM CL-ML Fines P L A S T I C I T Y I N D E X LIQUID LIMIT "U" Line "A" Line 34 32 32 30 31 NP 27 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 6 16 20 30 40 50 1.5 6 200 810 72.8 81.9 45.1 65.1 0.0 0.0 0.0 0.0 14 LL PL PI %Silt %Clay 1 4 3/4 1/2 60 fine U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS HYDROMETER 17 22 NP 20 15 8 NP 7 D100 Cc Cu SILT OR CLAY 4 D30 D10 %Gravel %Sand 1 2 P1 P3 -12 -10 -8 -6 -4 -2 0 2 100 1,000 10,000 AXIAL STRAIN, % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D4546 NOTES: Sample exhibited 3.6 percent compression upon wetting under an applied pressure of 1,000 psf. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado PROJECT NUMBER: 20135044 PROJECT: UCH Building A and Parking Lot SITE: 1024 South Lemay Avenue Fort Collins, Colorado CLIENT: Aspen Engineering Fort Collins, Colorado EXHIBIT: B-4 Specimen Identification 9.0 ft Classification , pcf 1 76 27 WC, % LEAN CLAY with SAND(CL) LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. CONSOL_STRAIN-USCS 20135044.GPJ TERRACON2012.GDT 9/19/14 -12 -10 -8 -6 -4 -2 0 2 100 1,000 10,000 AXIAL STRAIN, % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D4546 NOTES: Sample exhibited 1.4 percent compression upon wetting under an applied pressure of 1,000 psf. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado PROJECT NUMBER: 20135044 PROJECT: UCH Building A and Parking Lot SITE: 1024 South Lemay Avenue Fort Collins, Colorado CLIENT: Aspen Engineering Fort Collins, Colorado EXHIBIT: B-5 Specimen Identification 9.0 ft Classification , pcf 2 88 25 WC, % LEAN CLAY with SAND(CL) LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. CONSOL_STRAIN-USCS 20135044.GPJ TERRACON2012.GDT 9/19/14 -12 -10 -8 -6 -4 -2 0 2 100 1,000 10,000 AXIAL STRAIN, % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D4546 NOTES: Sample exhibited 1.0 percent compression upon wetting under an applied pressure of 150 psf. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado PROJECT NUMBER: 20135044 PROJECT: UCH Building A and Parking Lot SITE: 1024 South Lemay Avenue Fort Collins, Colorado CLIENT: Aspen Engineering Fort Collins, Colorado EXHIBIT: B-6 Specimen Identification 2.0 ft Classification , pcf P1 110 14 WC, % SILTY SAND(SM) LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. CONSOL_STRAIN-USCS 20135044.GPJ TERRACON2012.GDT 9/19/14 -12 -10 -8 -6 -4 -2 0 2 100 1,000 10,000 AXIAL STRAIN, % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D4546 NOTES: Sample exhibited 2.9 percent compression upon wetting under an applied pressure of 150 psf. 1901 Sharp Point Drive, Suite C Fort Collins, Colorado PROJECT NUMBER: 20135044 PROJECT: UCH Building A and Parking Lot SITE: 1024 South Lemay Avenue Fort Collins, Colorado CLIENT: Aspen Engineering Fort Collins, Colorado EXHIBIT: B-7 Specimen Identification 2.0 ft Classification , pcf P3 87 18 WC, % SANDY SILTY CLAY(CL-ML) LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. CONSOL_STRAIN-USCS 20135044.GPJ TERRACON2012.GDT 9/19/14 APPENDIX C SUPPORTING DOCUMENTS Exhibit: C-1 Unconfined Compressive Strength Qu, (psf) 500 to 1,000 2,000 to 4,000 > 8,000 less than 500 1,000 to 2,000 4,000 to 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 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 or boulders, or both” to group name. 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 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. Design Soluble Sulfate Used to determine the quantitative amount of soluble sulfates within a soil mass. 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 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. Gravel Sand 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 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 BEDROCK Loose Medium Dense Dense 0 - 3 4 - 9 10 - 29 30 - 50 7 - 18 19 - 58 Very Soft Soft Medium-Stiff Stiff Very Stiff Standard Penetration or N-Value Blows/Ft. 2 - 4 4 - 8 8 - 15 < 3 5 - 9 19 - 42 > 42 30 - 49 50 - 89 20 - 29 Medium Hard Very Dense RELATIVE DENSITY OF COARSE-GRAINED SOILS Descriptive Term (Density) Very Loose > 50 Ring Sampler Blows/Ft. 0 - 6 59 - 98 > 99 Descriptive Term (Consistency) Hard 0 - 1 Ring Sampler Blows/Ft. 3 - 4 10 - 18 Ring Sampler Blows/Ft. < 30 90 - 119 Standard Penetration or N-Value Blows/Ft. Descriptive Term (Consistency) Weathered Firm Very Hard CONSISTENCY OF FINE-GRAINED SOILS (More than 50% retained on No. 200 sieve.) Density determined by Standard Penetration Resistance (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. _ 15 - 30 > 30 > 119 < 20 30 - 49 50 - 79 >79 Hard LEAN CLAY with SAND(CL) LEAN CLAY with SAND(CL) SILTY SAND(SM) SANDY SILTY CLAY(CL-ML) 32 30 NP 27 0.105 4.75 4.75 2 2 1 2 P1 P3 9.0 9.0 2.0 2.0 GRAIN SIZE IN MILLIMETERS PERCENT FINER BY WEIGHT coarse fine 3/8 3 100 3 2 140 COBBLES GRAVEL SAND USCS Classification 27.2 18.1 54.9 34.9 D60 coarse medium 9.0 9.0 2.0 2.0 Boring ID Depth Boring ID Depth GRAIN SIZE DISTRIBUTION ASTM D422 1901 Sharp Point Drive, Suite C Fort Collins, Colorado PROJECT NUMBER: 20135044 PROJECT: UCH Building A and Parking Lot SITE: 1024 South Lemay Avenue Fort Collins, Colorado CLIENT: Aspen Engineering Fort Collins, Colorado EXHIBIT: B-3 LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 20135044.GPJ TERRACON2012.GDT 9/19/14 18 17 14 22 13 NP 20 16 15 18 8 18 NP 7 77 73 62 82 55 45 65 LL USCS 1 1 1 2 3 P1 P3 ATTERBERG LIMITS RESULTS ASTM D4318 1901 Sharp Point Drive, Suite C Fort Collins, Colorado PROJECT NUMBER: 20135044 PROJECT: UCH Building A and Parking Lot SITE: 1024 South Lemay Avenue Fort Collins, Colorado CLIENT: Aspen Engineering Fort Collins, Colorado EXHIBIT: B-2 LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. ATTERBERG LIMITS 20135044.GPJ TERRACON2012.GDT 9/19/14 CL-ML ATTERBERG LIMITS LL-PL-PI ELEVATION (Ft.) DEPTH (Ft.) 5 10 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) No free water observed WATER LEVEL OBSERVATIONS 5 10 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) No free water observed WATER LEVEL OBSERVATIONS DEPTH (Ft.) 5 10 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) No free water observed WATER LEVEL OBSERVATIONS LL-PL-PI ELEVATION (Ft.) Surface Elev.: 100.0 (Ft.) DEPTH (Ft.) 30 35 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) While drilling 8/29/14 WATER LEVEL OBSERVATIONS Fort Collins, Colorado Driller: Terracon Boring Completed: 8/25/2014 Exhibit: A-9 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI ELEVATION (Ft.) Surface Elev.: 100.0 (Ft.) DEPTH (Ft.) 5 10 15 20 25 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) While drilling 8/29/14 WATER LEVEL OBSERVATIONS LL-PL-PI ELEVATION (Ft.) Surface Elev.: 99.6 (Ft.) DEPTH (Ft.) 30 35 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) While drilling 8/29/14 WATER LEVEL OBSERVATIONS Exhibit: A-7 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI ELEVATION (Ft.) Surface Elev.: 99.6 (Ft.) DEPTH (Ft.) 5 10 15 20 25 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) While drilling 8/29/14 WATER LEVEL OBSERVATIONS LIMITS LL-PL-PI ELEVATION (Ft.) Surface Elev.: 99.5 (Ft.) DEPTH (Ft.) 30 35 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) While drilling 8/29/14 WATER LEVEL OBSERVATIONS Driller: Terracon Boring Completed: 8/25/2014 Exhibit: A-5 See Exhibit A-4 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: UCH Building A and Parking Lot FIELD TEST RESULTS SULFATES (%) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI ELEVATION (Ft.) Surface Elev.: 99.5 (Ft.) DEPTH (Ft.) 5 10 15 20 25 SAMPLE TYPE WATER LEVEL OBSERVATIONS SWELL (%) While drilling 8/29/14 WATER LEVEL OBSERVATIONS 13 1A 1 BB1 BB3 BB2 BB4 9 SB5 SB4 APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 2007 (PROJECT NO. 20075039; REPORT DATED 5/14/07) 1 1 2 3 4 5 6 7 8 9 APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 2006 (PROJECT NO. 20065163; REPORT DATED 11/30/06) 1 1 2 4 3 5 6 APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 1989 (PROJECT NO. 8058-89; REPORT DATED 7/21/89) 1 1 2 APPROXIMATE BORING LOCATION COMPLETED DURING PREVIOUS STUDY IN 2006 (PROJECT NO. 20065159; REPORT DATED 11/7/06) 1 APPROXIMATE BORING LOCATION FOR CURRENT GEOTECHNICAL STUDY FOR BUILDING A AND PARKING LOT 1 2 3 P1 P2 P3 using an equivalent fluid weighing 90 and 100 pcf for active and at-rest conditions, respectively. For 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. 4.7 Pavements 4.7.1 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