Geotechnical Engineering Evaluation Campbell County Athletic Play Fields Campbell County High School South Campus Gillette, Wyoming

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1 March 9, 2016 Proposal No. WYP16064 Campbell County School District Mr. Andy Mravlja 1000 W. 8 th Street Gillette, WY amravlja@ccsd.k12.wy.us RE: PROPOSAL Geotechnical Engineering Evaluation Campbell County Athletic Play Fields Campbell County High School South Campus Gillette, Wyoming Greetings Mr. Mravlja: STRATA, a Professional Services Corporation, (STRATA) is pleased to present this proposal for geotechnical engineering services for the athletic play fields to be constructed in Gillette, Wyoming. STRATA is a regional professional services provider specializing in geotechnical and environmental consulting, design, inspection, and testing services. We have been providing services to the Rocky Mountain region since We base this proposal on a request from you and a schematic design drawing dated July 2, 2012 and our conversation on March 8, The following text summarizes our project understanding, proposed scope of services, anticipated schedule, and estimated fee. Site Description PROJECT UNDERSTANDING The project is located directly south of the existing Campbell County South Campus High School at 4001 Saunders Boulevard. Presently the site is being used as a play field for the high school, and is covered with irrigated grass. The site is bound on the north by an access road and the South Campus High School, on the south by a residential subdivision, on the west by more play fields, and on the east by 4-J Road. The site is relatively flat, with less than a couple of feet of elevation change across the site. Otherwise the site is vacant with the exception of score boards and goal posts. Based on our experience at the south campus facility and other nearby projects, we anticipate subsurface soil consists of about 20 feet of potentially expansive soil overlying dense sand grading to sandstone. We anticipate groundwater will be encountered at a depth of 20 to 30 feet Schoonover Street, P.O. Box 4098, Gillette, Wyoming Phone Fax

2 Page 2 Photograph 1. Project Site Looking West Proposed Construction The facility will cover an area of about 7 acres, and will include a football field, track, 2 sets of permanent bleachers, a maintenance building, two concessions/ticket buildings, a locker room building, pole-vault runway, long jump sand pits, shot put and discus throwing areas, and field lighting. We understand the home team bleacher will contain a 2-story press box, restrooms, and an elevator. The visiting bleachers will include a storage building. Based on the schematic design, there will be large exterior slabs-on-grade and sidewalks on the north, south, and west sides of the track. A 4 to 5 foot tall concrete retaining wall is planned for the south end of the track. We anticipate the project will be serviced with city and franchise utilities from the access road on the north side of the project site. Subsurface utilities will typically extend 3 to 6 feet below finished grades. Landscaping improvements will also be constructed across the facility. Based on our experience in the area, the buildings will be constructed on a deep foundation such as helical piers or driven piles. Due to the expansive soil, we anticipate significant improvement will be required to the subgrade soil below slabs-on-grade. We estimate design loads for the proposed structures will range from 10 to 40 kips for columns, and 1 to 3 kips per lineal foot for continuous footings. Tolerable settlement criteria for this project have not been provided. Unless otherwise informed, we have assumed that total and differential settlements on the order of 1 inch and ½ inch in 25 feet are acceptable. No basements are planned for any of the buildings; however, we anticipate the elevator will have a below grade pit. PROPOSED SCOPE OF GEOTECHNICAL SERVICES We propose to accomplish a geotechnical evaluation at the site using exploratory drilling and laboratory testing. We will conduct field exploration and laboratory work in reference to appropriate ASTM International (ASTM) guidelines. Specifically, we propose to perform the following scope of our services: 1. Coordinate exploration with CCSD and One Call of Wyoming to perform utility locates prior to exploration as required by State law. STRATA cannot be responsible for damage to unregistered or unlocated utilities, including irrigation lines. Please identify private utilities in the exploration area. 2. Explore subsurface soil conditions via 14 borings at the locations specified on the schematic design as outlined in Table 1 below. Borings will be advanced to the depth shown, or auger refusal, whichever occurs first.

3 Page 3 Table 1. Proposed Explorations and Depths Facility Number of Borings Planned Boring Depth (ft) Home Bleachers/Press Box/Restrooms 2 20 to 40 Maintenance/Storage Building 1 20 to 40 Track and Stadium Lights 5 5 to 20 Home Concessions/Ticketing 1 20 North Locker Rooms 2 20 to 40 Visitor Concessions/Restrooms 1 20 Visiting Bleacher/Storage 2 20 to 40 Soil samples will be collected with Standard Penetration Tests (SPT) and ring-lined California samplers at 2½ to 5-foot intervals. Explorations will be loosely backfilled upon completion. Soil borings will be plugged at the surface with bentonite. All cuttings will remain on site. Exploration locations will not be landscaped, reseeded, or recompacted. Some rutting, landscape disturbance, and other surface damage must be anticipated as part of exploration. We will record depth to groundwater and bedrock in each exploration, if encountered. We will monitor exploration with our GeoProfessional staff, who will visually classify and describe the soil and groundwater encountered in explorations in reference to the Unified Soil Classification System (USCS). Should a subsurface anomaly be encountered requiring additional drilling, we will contact CCSD for authorization prior to incurring additional fees. We request CCSD provide STRATA with access to the site and staked boring locations prior to our field activities. 3. Perform laboratory tests on soil samples retained during exploration to evaluate their geotechnical engineering properties. Our project engineer will assign the laboratory testing program based on the soil conditions encountered during the field investigation and with respect to our analyses. Laboratory test results may include but are not limited to the following: Atterberg limits Grain size analysis Consolidation tests Natural density and moisture content Swell/collapse tests Soil ph, resistivity, & soluble sulfates The results of laboratory testing will be used to help characterize soil-engineering parameters and to correlate soil design factors such as compressibility, shear strength and subgrade modulus. 4. Perform geotechnical engineering analyses in order to provide geotechnical design and construction recommendations for planned site development. Our engineering analyses will provide opinions and recommendations for various aspects of construction as required by the design team. We anticipate the following geotechnical design areas will be evaluated and specific recommendations will result as part of our geotechnical analyses: Earthwork Site preparation Excavation characteristics Structural fill criteria Required compaction and moisture conditioning Wet weather construction Cold weather construction Suitability of the on-site soils for use as subgrade Geotextile Applications

4 Typical Shallow Foundation Design (if feasible) Allowable bearing pressure Soil improvement requirements (if needed) Total and differential settlement estimates Short-term loading increases IBC site class based on explored depths Lateral foundation base sliding friction coefficients Swell potential Collapse potential Frost Depth Deep Foundation Design (if necessary) Suitable foundation types Allowable bearing capacities Design factors of safety Estimated deflection Allowable uplift resistance Load test requirements Construction considerations L-Pile soil parameters for light pole foundations Concrete Slabs-On-Grade Minimum slab support section Modulus of subgrade reaction Soil Chemistry Sulfate attack Corrosion of buried metals Retaining Wall Recommendations Allowable bearing pressure Friction coefficients Active, at rest, and passive pressures Drainage recommendations Track Pavement Design Subgrade preparation Base course thickness Asphalt thickness Proposal for Geotechnical Services Page 4 5. Provide an electronic copy of the geotechnical plan sheets that will include a site plan, exploration logs, laboratory test data, our interpretation of subsurface conditions, and our geotechnically related opinions and recommendations. SCHEDULE AND FEES We anticipate the following timeframe: 1. We anticipate mobilizing equipment to the site within 2 weeks following written notice to proceed. Please note, adverse weather conditions which preclude site access may delay our exploration. We will notify you of such conditions to discuss alternative scheduling if required. 2. We estimate the field investigation will take 2 days to complete.

5 Page 5 3. We anticipate the laboratory and engineering analyses summarized on the final geotechnical plan sheets will be completed within 4 weeks following field work. Verbal recommendations may be provided as available prior to the final report. The total lump sum fee for these services will be $11, Our fee estimate is valid for a period of 90 days from the date of this proposal. Should subsurface conditions warrant a change in scope, i.e., additional services such as more exploration or laboratory testing, or concrete pavement to mention a few, we will request any fee changes prior exceeding the proposed budget. Construction observation and materials testing services are not included in this scope of work. If you desire these or other services, please contact us for a revised proposal. LIMITATIONS The geotechnical scope of services presented above has been developed based on our understanding of the proposed development. The scope of services presented above does not include retaining wall design, stormwater or septic disposal design, global wall stability, structural design, erosion control design, evaluation of hazardous materials, delineation of wetlands, or any other services not explicitly discussed above. We will endeavor to perform our evaluation referencing the standard of care as it exists in Wyoming at the time of this proposal. This acknowledgement will be in lieu of any express or implied warranties. Construction observation and materials testing services are not included in this scope of work; however, testing and observation during construction is critical to the successful implementation of our engineering recommendations. We recommend that we be retained to perform these services. INHERENT RISKS There are inherent risks whenever soil, geologic or hydrogeologic conditions are involved with a development. These risks must be emphasized when the potential for damage to property also exists. Soil and geologic material including groundwater are variable in nature. STRATA s exploration will identify the conditions at the time of evaluation and in the locations explored. Geologic conditions may change between exploration points and at depth. Should you elect not to incorporate our recommendations into construction, or do not retain STRATA to verify our findings during construction, you agree to defend, indemnify and hold STRATA harmless from and against any and all claims resulting from the exclusion of our recommendations. In authorizing our services, you understand and accept the above limitations. ACCEPTANCE We anticipate this work will be performed under the State School Facilities District Contract for Professional Services. If you agree to the above scope of services, please forward us a copy of the agreement as authorization to proceed. Sincerely, STRATA, Inc. Dennis A. Russell, P.E. Wyoming Engineering Manager Taunya Ernst, P.E., P.G. Senior Geotechnical Engineer DAR/TE/lr 16GEOPROPS/WYP16064.DOC