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HomeMy WebLinkAbout2020-06-23_FULL STORMWATER REPORT WITH ATTACHMENTS BILLINGS CLINIC BOZE MAN AMBULATORY DESTINATION CENTER P HASE 1 FINAL DRAINAGE REPORT BOZEMAN , MONTANA CERTIFICATION I hereby state that this Final Drainage Report has been prepared by me or under my supervision and meets the standard of care and expertise which is usual and customary in this community of professional engineers. The analysis has been prepared utilizing procedures and practices specified by the City of Bozeman and within the standard accepted practices. ____________________________________________ ___________________________ Pat Davies, P.E. Date 06/23/2020 June 23, 2020 Project No. 15063.03 DRAINAGE REPORT BILLINGS CLINIC AMBU LATORY DESTINATION C ENTER BOZEMAN, MONTANA OVERVIEW NARRATIVE The purpose of this drainage plan is to present a summary of calculations to quantify the stormwater runoff for Phase I of the Billings Clinic Ambulatory Destination Center project. All design criteria and calculations are in accordance with The City of Bozeman Design Standards and Specifications Policy , dated March 2004. The site stormwater improvements have been designed with the intent to meet the current City of Bozeman drainage regulations for the entire site to the extent feasible. Stormwater for future build-out of the property will be considered in future SP1 submittals. For off- site infrastructure stormwater design, please refer to the Infrastructure submittal. The Phase 1 site is located off East Valley Center Road just south of Westlake Road between Davis Lane and North 27 th Avenue and is approximately 10.90 acres. The onsite project area currently consists of unimproved land. The onsite Phase I project will include the construction of two new buildings, surface parking, and other surface and landscape improvements. Stormwater facilities proposed for the onsite development include a series of inlets and piping that are routed to two separate underground boulder pits for retention and infiltration/treatment of all runoff. Calculations for each onsite sub-basin and boulder pit are included in this submittal. I. Design Approach The modified rational method was used to determine peak runoff rates and volumes. The rational formula provided in The City of Bozeman Standard Specifications and Policy was used to calculate the peak runoff rates on site, time of concentration, rainfall intensities, etc. We assumed a time of concentration of 5-minutes. For impervious surfaces, a runoff coefficient of 0.95 was assumed, and for pervious surfaces, a runoff coefficient of 0.15 was assumed. Infiltration rates provided in the Geotech Report were considered in the sizing of both boulder pits. The average of the 1-hour lowest infiltration rate calculated for each of the six tests performed was 3.12 in/hour. This rate is divided by 2 in the ‘cfs’ column to be conservative. Infiltration rate field data can be found in the attachments of the Geotech Report. II. Proposed On-Site Watershed Descriptions The watershed basins in this section include runoff from only the Phase I development. For the following sections, please refer to Exhibit A of this report, which graphically shows and labels the off-site watersheds as well as the proposed V:2020-06-23_BILLINGS CLINIC DRAINAGE REPORT 2 (06/23/20) JAZ drainage and storage facilities. Percolation rates have been included in these calculations. All calculations used the 10-year, 2-hour design storm frequency for rainfall data. A void ration of 0.38 was assumed. All stormwater will be stored, treated, and infiltrated on site. West Basin (Blue) The West Basin consists of the western 4.23 Acres of the proposed Phase I development. Based on a rational method analysis of the pervious and impervious areas for the basin, the required site retention volume was calculated to be 7,864 ft 3. The West Boulder Pit is located on the north side of the West Basin and is sized as follows: 173’ (L) x 15’ (W) x 8’ (D). Considering a void ratio of 0.38, the West Boulder Pit provides 7,889 ft 3 of storage, so adequate storage is provided for the West Basin. East Basin (Red) The East Basin consists of the western 6.67 Acres of the proposed Phase I development. Based on a rational method analysis of the pervious and impervious areas for the basin, the required site retention volume was calculated to be 11,043 ft 3. The East Boulder Pit is located on the north side of the West Basin and is sized as follows: 208’ (L) x 20’ (W) x 7’ (D). Considering a void ratio of 0.38, the East Boulder Pit provides 11,066 ft 3 of storage, so adequate storage is provided for the East Basin. III. Water Quality The City of Bozeman Design Standards and Specifications Policy states the requirement to capture or reuse the runoff generated from the first 0.5 inches of rainfall from a 24-hour storm. We meet this requirement by retaining all storm runoff on site with no discharge into the City storm drain system for the 10-year, 2-hour design storm. IV. Outlet Structures All runoff will be captured and retained/infiltrated using the proposed boulder pits. There are no outlet structures proposed for this project. V. Conveyance Pipes Pipes are sized to convey the 25-year storm event as required by the City of Bozeman Design Standards and Specifications Policy. Calculations are provided in the Appendix B. Refer to Exhibit B in Appendix B for sub-basin and pipe labeling. VI. Appendices Appendix A – Exhibit A – Stormwater Basins Appendix B – Hydrology Calculations Appendix C – Surface Improvements O&M Plan Appendix D – Geotechnical Investigation V:2020-06-23_BILLINGS CLINIC DRAINAGE REPORT 5 (06/23/20) JAZ Appendix A EXHIBIT A – STORMWATER BASINS V:2020-06-23_BILLINGS CLINIC DRAINAGE REPORT 6 (06/23/20) JAZ Appendix B HYDROLOGY CALCULATIONS Project: Billings Clinic Bozeman Project #: 15063.03 Date: 6/23/2020 Design Storm Frequency =10 years Discharge Rate, d =0.09 cfs Length (ft) Width (ft) (in/hr)* cfs 173 15 3.12 0.09 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 123813 2.842 0.95 1 0.95 0.95 2.70 60272 1.384 0.15 1 0.15 0.15 0.21 1 0.00 0.00 0 1 0.00 0.00 0 1 0.00 0.00 0 184085 4.2260 2.9078 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =2.91 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 9.16 26.64 5 3.22 9.36 10 2.05 5.96 15 1.58 4.58 20 1.31 3.80 25 1.13 3.29 30 1.00 2.92 35 0.91 2.64 40 0.83 2.42 45 0.77 2.24 50 0.72 2.10 55 0.68 1.97 60 0.64 1.86 75 0.55 1.61 90 0.49 1.43 105 0.44 1.29 120 0.41 1.19 150 0.35 1.03 180 0.31 0.91 360 0.20 0.58 720 0.13 0.37 1440 0.08 0.24 7,864.27 ft3 9.36 (ft3/s) Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS West Basin (Blue) - POST-IMPROVEMENT CONDITIONS Surface Type Permeability Area of Boulder Pit Discharge *Based on geotech report. Discharge flow rate assumes 50% percolation rate. Pervious Totals = 0.6881 Cwd x Cf =0.69 Runoff Volume Discharge Volume Site Detention = = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3) (ft3) (ft3) 1598.42 5.62 1592.80 2807.58 28.11 2779.46 3578.43 56.23 3522.20 4124.05 84.34 4039.71 4560.92 112.45 4448.47 4931.41 140.56 4790.85 5256.35 168.68 5087.68 5547.74 196.79 5350.95 5813.17 224.90 5588.27 6057.82 253.01 5804.81 6285.38 281.13 6004.25 6498.59 309.24 6189.35 6699.54 337.35 6362.19 7243.75 421.69 6822.06 7721.06 506.03 7215.03 8149.07 590.36 7558.71 8538.97 674.70 7864.27 9232.60 843.38 8389.22 9840.96 1012.05 8828.91 12542.90 2024.10 10518.80 15986.68 4048.20 11938.48 20375.99 8096.40 12279.59 = Project: Billings Clinic Bozeman Project #: 15063.03 Date: 6/23/2020 Design Storm Frequency =10 years Discharge Rate, d =0.15 cfs Length (ft) Width (ft) (in/hr)* cfs 208 20 3.12 0.15 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 170299 3.910 0.95 1 0.95 0.95 3.71 120493 2.766 0.15 1 0.15 0.15 0.41 1 0.00 0.00 0 1 0.00 0.00 0 1 0.00 0.00 0 290792 6.6757 4.1290 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =4.13 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 9.16 37.83 5 3.22 13.29 10 2.05 8.47 15 1.58 6.51 20 1.31 5.40 25 1.13 4.67 30 1.00 4.15 35 0.91 3.75 40 0.83 3.44 45 0.77 3.19 50 0.72 2.98 55 0.68 2.80 60 0.64 2.64 75 0.55 2.29 90 0.49 2.03 105 0.44 1.84 120 0.41 1.68 150 0.35 1.46 180 0.31 1.29 360 0.20 0.82 720 0.13 0.53 1440 0.08 0.33 11,043.49 ft3 13.29 (ft3/s) 22700.62 6489.60 16211.02 28933.32 12979.20 15954.12 13973.87 1622.40 12351.47 17810.55 3244.80 14565.75 12125.09 1081.60 11043.49 13110.02 1352.00 11758.02 10963.68 811.20 10152.48 11571.45 946.40 10625.05 9513.15 540.80 8972.35 10285.91 676.00 9609.91 8925.06 450.67 8474.39 9227.80 495.73 8732.07 8254.53 360.53 7894.00 8601.93 405.60 8196.33 7463.87 270.40 7193.47 7877.62 315.47 7562.16 6476.37 180.27 6296.11 7002.46 225.33 6777.12 5081.26 90.13 4991.13 5856.03 135.20 5720.83 2269.72 9.01 2260.70 3986.68 45.07 3941.61 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3) (ft3) (ft3) = 0.6185 Cwd x Cf =0.62 Runoff Volume Discharge Volume Site Detention = Pervious Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS EAST BASIN (RED) - POST-IMPROVEMENT CONDITIONS Surface Type Permeability Area of Boulder Pit Discharge *Based on geotech report. Discharge flow rate assumes 50% percolation rate. = Project: Billings Clinic Bozeman Project #: 15063.03 Date: 6/23/2020 TABLE I-1: Runoff Coefficients for Use in the Rational Method LAND USE RUNOFF COEFFICIENTS, C Open Land 0.2 Low to Medium Density Residential 0.35 Dense Residential 0.5 Commercial Neighborhood 0.6 Commercial Downtown 0.8 Industrial 0.8 Project: Billings Clinic Bozeman Project #: 15063.03 Date: 6/23/2020 Design Standards and Specifications Policy City of Bozeman, March 2004 as Amended RAINFALL INTENSITY-DURATION CURVES (Figures I-2, I-3) Time 2 5 10 25 50 100 (min)(in/hr)(in/hr)(in/hr)(in/hr)(in/hr)(in/hr) 1 4.20 7.15 9.16 10.72 13.72 15.69 5 1.60 2.55 3.22 3.83 4.74 5.34 10 1.05 1.64 2.05 2.46 3.00 3.35 15 0.83 1.26 1.58 1.89 2.30 2.56 20 0.70 1.05 1.31 1.58 1.90 2.11 25 0.61 0.91 1.13 1.37 1.64 1.82 30 0.55 0.81 1.00 1.22 1.45 1.61 35 0.50 0.73 0.91 1.10 1.31 1.45 40 0.46 0.67 0.83 1.01 1.20 1.33 45 0.43 0.63 0.77 0.94 1.11 1.22 50 0.40 0.58 0.72 0.88 1.04 1.14 55 0.38 0.55 0.68 0.82 0.97 1.07 60 0.36 0.52 0.64 0.78 0.92 1.01 75 0.31 0.45 0.55 0.68 0.79 0.87 90 0.28 0.40 0.49 0.60 0.70 0.77 105 0.26 0.36 0.44 0.55 0.64 0.69 120 0.24 0.33 0.41 0.50 0.58 0.63 150 0.21 0.29 0.35 0.43 0.50 0.55 180 0.19 0.26 0.31 0.39 0.45 0.48 360 0.12 0.17 0.20 0.25 0.28 0.30 720 0.08 0.11 0.13 0.16 0.18 0.19 1440 0.05 0.07 0.08 0.10 0.11 0.12 Storm Recurrence Interval Project: Billings Clinic Bozeman Project #: 15063.03 Date: 6/23/2020 Design Standards and Specifications Policy City of Bozeman, March 2004 as Amended Zoning District/Design Storm Requirement Zoning Type Design Rainfall Frequency Open Land 2-year Residential 10-year Commercial 10-year (p. 28, Table I-3) Project: Billings Clinic Bozeman Project #: 15063.03 Date: 6/23/2020 STORMWATER MANAGEMENT MANUAL TABLE 2-5 FREQUENCY FACTORS FOR THE RATIONAL FORMULA Recurrence Interval Adjustment Factor (Years)Cf 2 1.00 5 1.00 10 1.00 25 1.10 50 1.20 100 1.25 * C X Cf should not exceed 1.0 Billings Clinic Bozeman Pipe Sizing Analysis Exhibit B (East & West Basins) NUMBER = SUB-BASIN LETTER = PIPE Sub-Basin Area (SF)Area (AC)C Coefficient C*Area Weighted C Pipe A Basin 1 7,070 0.16 0.81 Area (AC)C Area x C Landscape 1,208 0.03 0.15 0.00 Basin 1 0.16 0.81 0.13 Impervious 5,862 0.13 0.95 0.13 Total 0.16 0.13 Weighted C 0.81 Basin 2 4,880 0.11 0.89 Landscape 360 0.01 0.15 0.00 Pipe B Impervious 4,520 0.10 0.95 0.10 Area (AC)C Area x C Basin 1 0.16 0.81 0.13 Basin 3 36,261 0.83 0.82 Basin 2 0.11 0.89 0.10 Landscape 5,845 0.13 0.15 0.02 Total 0.27 0.23 Impervious 30,416 0.70 0.95 0.66 Weighted C 0.85 Basin 4 49,433 1.13 0.71 Pipe C Landscape 15,124 0.35 0.15 0.05 Area (AC)C Area x C Impervious 34,309 0.79 0.95 0.75 Basin 3 0.83 0.82 0.68 Total 0.83 0.68 Basin 5 15,032 0.35 0.79 Weighted C 0.82 Landscape 2,927 0.07 0.15 0.01 Impervious 12,105 0.28 0.95 0.26 Pipe D Area (AC)C Area x C Basin 6 71,406 1.64 0.71 Basin 1 0.16 0.81 0.13 Landscape 21,621 0.50 0.15 0.07 Basin 2 0.11 0.89 0.10 Impervious 49,785 1.14 0.95 1.09 Basin 3 0.83 0.82 0.68 Total 1.11 0.92 Weighted C 0.83 Pipe E Area (AC)C Area x C Basin 1 0.16 0.81 0.13 Basin 2 0.11 0.89 0.10 Basin 3 0.83 0.82 0.68 Basin 4 1.13 0.71 0.80 Total 2.24 1.72 Weighted C 0.77 Pipe F Area (AC)C Area x C Basin 1 0.16 0.81 0.13 Basin 2 0.11 0.89 0.10 Basin 3 0.83 0.82 0.68 Basin 4 1.13 0.71 0.80 Basin 5 0.35 0.79 0.27 Total 2.59 1.99 Weighted C 0.77 Pipe G Area (AC)C Area x C Basin 1 0.16 0.81 0.13 Basin 2 0.11 0.89 0.10 Basin 3 0.83 0.82 0.68 Basin 4 1.13 0.71 0.80 Basin 5 0.35 0.79 0.27 Basin 6 1.64 0.71 1.16 Total 4.23 3.15 Weighted C 0.75 (Includes Basin 1, 2, 3, & 4) (Includes Basin 1, 2, 3, 4, & 5) (Includes Basin 1, 2, 3, 4, 5, & 6) Sub-Basin Runoff Coefficient Worksheet (Includes Basin 1) (Includes Basin 1 & 2) Pipe Area and Curve Number Worksheet (Includes Basin 3) (Includes Basin 1, 2, & 3) West Basin Pipe Sizing Worksheet 25-YR Storm A B 1 0. 8 1 5. 0 0 3. 8 3 0 0. 1 6 2 0. 5 1 72 0. 0 0 6 0 8 0. 9 4 2.69 0.54 0.59 0.87 4.74 2.35 B D 1- 2 0. 8 5 5. 0 0 3. 8 3 0 0. 2 7 4 0. 8 9 58 0. 0 0 4 0 12 2. 2 6 2.88 0.39 0.49 0.80 5.94 2.29 C D 3 0. 8 2 5. 0 0 3. 8 3 0 0. 8 3 2 2. 6 2 14 4 0. 0 0 6 0 12 2. 7 7 3.52 0.95 0.87 1.03 10.44 3.63 D E 1- 3 0. 8 3 5. 0 0 3. 8 3 0 1. 1 0 7 3. 5 1 18 8 0. 0 1 0 0 12 3. 5 7 4.55 0.98 0.90 1.04 10.83 4.73 E F 1- 4 0. 7 7 5. 0 0 3. 8 3 0 2. 2 4 2 6. 5 7 13 7 0. 0 1 1 0 15 6. 7 9 5.54 0.97 0.89 1.04 13.35 5.74 F G 1- 5 0. 7 7 5. 0 0 3. 8 3 0 2. 5 8 7 7. 6 2 10 8 0. 0 1 4 0 15 7. 6 6 6.25 0.99 0.91 1.04 13.72 6.50 G B P 1 - 6 0 . 7 5 5 . 0 0 3 . 8 3 0 4 . 2 2 6 12 . 0 6 78 0 . 0 1 3 2 1 8 12 . 1 0 6.85 1.00 0.92 1.04 16.51 7.13 min 2.5 ft/sec Max 0.99 We s t B a s i n P i p e S i z i n g W o r k s h e e t 2 5 - Y R S t o r m Do w n s t r e a m Pi p e # Pi p e # We i g h t e d C Es t i m a t e d TO C ( M i n ) IN T * , i (i n / h r ) V Actual Velocity (ft/sec) Q F L O W (C i A ) (c f s ) Pi p e Le n g t h ( f t ) Pi p e S l o p e (f t / f t ) Pi p e Si z e ( i n ) d Qf F l o w F u l l Ca p a c i t y ( c f s ) Vf Flow Full Velocity (ft/sec) In l c u d e d Ba s i n s To t a l Ar e a ( A ) (a c ) Q/Qf d/D V/Vf Sub-Basin Area (SF)Area (AC)C Coefficient C*Area Weighted C Pipe A Basin 1 4,659 0.11 0.57 Area (AC)C Area x C Landscape 2,185 0.05 0.15 0.01 Basin 1 0.11 0.57 0.06 Impervious 2,474 0.06 0.95 0.05 Total 0.11 0.06 Weighted C 0.57 Basin 2 24,611 0.56 0.72 Landscape 7,160 0.16 0.15 0.02 Pipe B Impervious 17,451 0.40 0.95 0.38 Area (AC)C Area x C Basin 1 0.11 0.57 0.06 Basin 3 21,542 0.49 0.73 Basin 2 0.56 0.72 0.41 Landscape 6,030 0.14 0.15 0.02 Total 0.67 0.47 Impervious 15,512 0.36 0.95 0.34 Weighted C 0.69 Basin 4 18,192 0.42 0.71 Pipe C Landscape 5,545 0.13 0.15 0.02 Area (AC)C Area x C Impervious 12,647 0.29 0.95 0.28 Basin 1 0.11 0.57 0.06 Basin 2 0.56 0.72 0.41 Basin 5 57,879 1.33 0.68 Total 0.67 0.47 Landscape 19,328 0.44 0.15 0.07 Weighted C 0.69 Impervious 38,551 0.89 0.95 0.84 Pipe D Basin 6 3,711 0.09 0.76 Area (AC)C Area x C Landscape 862 0.02 0.15 0.00 Basin 1 0.11 0.57 0.06 Impervious 2,849 0.07 0.95 0.06 Basin 2 0.56 0.72 0.41 Basin 3 0.49 0.73 0.36 Basin 7 87,333 2.00 0.55 Total 1.17 0.83 Landscape 43,206 0.99 0.15 0.15 Weighted C 0.71 Impervious 44,127 1.01 0.95 0.96 Pipe E Basin 8 40,313 0.93 0.46 Area (AC)C Area x C Landscape 24,573 0.56 0.15 0.08 Basin 4 0.42 0.71 0.29 Impervious 15,740 0.36 0.95 0.34 Total 0.42 0.29 Weighted C 0.71 Basin 9 32,457 0.75 0.72 Landscape 9,312 0.21 0.15 0.03 Pipe F Impervious 23,145 0.53 0.95 0.50 Area (AC)C Area x C Basin 4 0.42 0.71 0.29 Basin 5 1.33 0.68 0.91 Total 1.75 1.20 Weighted C 0.69 Pipe G Area (AC)C Area x C Basin 4 0.42 0.71 0.29 Basin 5 1.33 0.68 0.91 Basin 6 0.09 0.76 0.07 Total 1.83 1.27 Weighted C 0.69 Pipe H Area (AC)C Area x C Basin 1 0.11 0.57 0.06 Basin 2 0.56 0.72 0.41 Basin 3 0.49 0.73 0.36 Basin 4 0.42 0.71 0.29 Basin 5 1.33 0.68 0.91 Basin 6 0.09 0.76 0.07 Total 3.00 2.09 Weighted C 0.70 Pipe I Area (AC)C Area x C Basin 1 0.11 0.57 0.06 Basin 2 0.56 0.72 0.41 Basin 3 0.49 0.73 0.36 Basin 4 0.42 0.71 0.29 Basin 5 1.33 0.68 0.91 Basin 6 0.09 0.76 0.07 Total 3.00 2.09 Weighted C 0.70 Pipe J Area (AC)C Area x C Basin 1 0.11 0.57 0.06 Basin 2 0.56 0.72 0.41 Basin 3 0.49 0.73 0.36 Basin 4 0.42 0.71 0.29 Basin 5 1.33 0.68 0.91 Basin 6 0.09 0.76 0.07 Basin 7 2.00 0.55 1.11 Total 5.00 3.20 Weighted C 0.64 (Includes Basin 1, 2, 3, 4, 5, & 6) (Includes Basin 1, 2, 3, 4, 5, & 6) (Includes Basin 1, 2, 3, 4, 5, 6 & 7) (Includes Basin 4) (Includes Basin 4 & 5) (Includes Basin 4, 5, & 6) Sub-Basin Runoff Coefficient Worksheet (Includes Basin 1) (Includes Basin 1 & 2) Pipe Area and Curve Number Worksheet (Includes Basin 1 & 2) (Includes Basin 1, 2, & 3) A B 1 0. 5 7 5. 0 0 3. 8 3 0 0. 1 0 7 0. 2 4 15 1 0. 0 0 6 0 8 0. 9 4 2.69 0.25 0.39 0.70 3.14 1.89 B C 1- 2 0. 6 9 5. 0 0 3. 8 3 0 0. 6 7 2 1. 7 9 51 0. 0 0 4 0 12 2. 2 6 2.88 0.79 0.75 0.98 9.01 2.82 C D 1- 2 0. 6 9 5. 0 0 3. 8 3 0 0. 6 7 2 1. 7 9 18 5 0. 0 0 4 0 12 2. 2 6 2.88 0.79 0.75 0.98 9.01 2.82 D H 1- 3 0. 7 1 5. 0 0 3. 8 3 0 1. 1 6 6 3. 1 6 80 0. 0 0 8 0 12 3. 2 0 4.07 0.99 0.91 1.04 10.93 4.23 E F 4 0. 7 1 5. 0 0 3. 8 3 0 0. 4 1 8 1. 1 3 33 0. 0 0 8 8 8 1. 1 4 3.26 0.99 0.91 1.04 7.31 3.39 F G 4- 5 0. 6 9 5. 0 0 3. 8 3 0 1. 7 4 6 4. 6 0 94 0. 0 1 7 0 12 4. 6 6 5.93 0.99 0.91 1.04 10.91 6.17 G H 4- 6 0. 6 9 6. 0 0 3. 8 3 0 1. 8 3 2 4. 8 5 62 0. 0 0 6 0 15 5. 0 2 4.09 0.97 0.89 1.04 13.35 4.24 H I 1- 6 0. 7 0 7. 0 0 3. 8 3 0 2. 9 9 8 8. 0 2 58 0. 0 1 6 0 15 8. 1 9 6.68 0.98 0.90 1.04 13.50 6.94 I J 1- 6 0. 7 0 8. 0 0 3. 8 3 0 2. 9 9 8 8. 0 2 24 2 0. 0 1 6 0 15 8. 1 9 6.68 0.98 0.90 1.04 13.50 6.94 J B P 1 - 7 0 . 6 4 5 . 0 0 3 . 8 3 0 5 . 0 0 3 12 . 2 7 10 0 0 . 0 1 4 0 1 8 12 . 4 6 7.05 0.98 0.91 1.04 16.31 7.34 min 2.5 ft/sec Max 0.99 Ea s t B a s i n P i p e S i z i n g W o r k s h e e t 2 5 - Y R S t o r m Do w n s t r e a m Pi p e # Pi p e # We i g h t e d C Es t i m a t e d TO C ( M i n ) IN T * , i (i n / h r ) V Actual Velocity (ft/sec) Q F L O W (C i A ) (c f s ) Pi p e Le n g t h ( f t ) Pi p e S l o p e (f t / f t ) Pi p e Si z e ( i n ) d Qf F l o w F u l l Ca p a c i t y ( c f s ) Vf Flow Full Velocity (ft/sec) In l c u d e d Ba s i n s To t a l Ar e a ( A ) (a c ) Q/Qf d/D V/Vf V:2020-06-23_BILLINGS CLINIC DRAINAGE REPORT 7 (06/23/20) JAZ Appendix C O&M PLAN June 23, 2020 Project No. 15063.03 STORMWATER OPERATION & MAINTENA NCE MANUAL FOR BILLINGS CLINIC AMBULATORY DESTINATION CENTER BOZ EMAN , M ONTANA I. INTRODUCTION The purpose of this manual is to summarize the tasks required for perpetual maintenance to ensure the proper operation of stormwater facilities for the Billings Clinic Bozeman Ambulatory Destination Center located in Bozeman, Montana. II. CONTACT The responsible party for operation and maintenance of this facility is: Billings Clinic 2800 10 th Avenue North Billings, MT 59101 III. MAINTENANCE The following is a list of maintenance tasks and the frequency they are to be performed: 1. Inspect exterior of catch basins on a semi-annual basis and after storm events producing at least 0.5-inches of precipitation. 2. Inspect interior of catch basins and deep sumps for debris and sediment on a semi-annual basis and after storm events larger than 0.5-inches of precipitation. Clean out if sediment fills 60-percent of sump or comes within 6-inches of a pipe. 3. Inspect inlets for trash, obstructions and vegetation on a semi-annual basis and after storm events larger than 0.5-inchs of precipitation. P:2020-06-23_BILLINGS CLINIC BOZEMAN O&M 2 (06/23/20) JAZ IV. INSPECTION CHECKLIST Attached in the appendix of the manual is an “Annual Inspection Checklist” to be performed by the responsible party on an annual basis. V. FACILITY REPLACEMENT SCHEDULE The following is a list of drainage components and their expected design life based on typical usage. We recommend budgeting for replacement of each component based on the schedule below, but proper maintenance and up-keep of the facilities could significantly prolong the design life. 1. Storm drain inlets a. Design life = 100 years b. Replacement schedule = 100 years 2. Storm drain piping a. Design life = 100 years b. Replacement schedule = 100 years 3. Boulder Pit a. Design life = 100 years b. Replacement schedule = 100 years VI. SITE PLAN Attached in the appendix of the manual are the grading plans showing the site grading concept and drainage facilities. I agree to the above operation, maintenance and replacement schedule detailed above. Signature : __________________________________________ Billings Clinic Representative. APPENDICES 1. Annual Inspection Checklist Checklist continued on next page INSPECTOR’S NAME:DATE:NAME & ADDRESS OF STORMWATERFACILITY:GENERAL OBSERVATIONS (IS WATERFLOWING?):WEATHER:Checked? (Y/N)Maintenance Needed? (Y/N)Observations and Remarks Look for debris, trash and sediment blocking catch basin grate. If found, remove. Replace grate if damaged.Inspect filter if installed. Change if torn or clogged.Look for sediment and trash in catch basin sump. Clean out if sediment fills 60% of the sump or comes within 6” of a pipe.Look for damage or cracks to frame, grate, basin walls or bottom. If found, repair or replace.Check integrity of ladder rungs, cleanout gate, and orifice plate. If bent or obstructed, take appropriate action. Check for undercutting, scouring, and slumping. If found, repair or maintain.Remove all trash and loose sediment. Remove sediment if it will impede water flow or clog downstream structures.Remove vegetation that impedes water movement. Remove vegetation over 9” in height, and all trees and shrubs impeding flow.Repair check dams as necessary.Remove any dumped yard waste.In ditches and swales, check for integrity of grass, check dams, inlets, and outlets. Remove shrubs and trees. CATCH BASINS AND INLETS CONVEYANCES Stormwater System Inspection Checklist G-6 | Page Checked? (Y/N)Maintenance Needed? (Y/N)Observations and Remarks Inlets and outlets: remove vegetation and debris. Fix erosion and scouring. Fix cause of sediment found below outlet.Remove vegetation and debris from trash rack.Add rock to energy dissipater if missing.If necessary, repair rock on spillway. Remove trees, shrubs, and vegetation over 4”. If piping or erosion is visible, consult engineer. Check for slumping or sloughing of walls. If over 4” of slumping, consult with an engineer. Fix any erosion or scouring. If leaks, piping or soft spots are found, consult with an engineer.If liner visible on bottom, check for holes or replace.Clean any oil sheen from water with oil-absorbent pads or vactor truckChecksediment depth near inlet.If more than one footexists,or there is build upnear inlet,the pond needs to becleaned. On the pond walls, mow grass to 4 – 9”. Remove clippings. Reseed bare areas.On pond surface, emergent vegetation over 50% of the area indicates sediment removal needed.On pond bottom, remove tree seedlings.Around the pond,remove trees and shrubs that shadesidewallgrassorthatmighthaveproblemrootsnearpipes and structures.Remove invasive and poisonous plants.Remove algae if over 10% of surface.Check integrity of access ramp; ensure stable and clear for heavy equipment.Check integrity and operation of all fences, gates, and locks. Repair as needed for ease of access.Remove rodents and insects if evidence found.Remove vegetation on fences. POND COMPONENTS OF THE POND ACCESS AND SAFETY VEGETATION G-7 | Page POST CONSTRUCTION BMP INSPECTION CHECKLIST MonthlySchedule/Frequency AnnuallyAnnually Inspect pond area, sidewalls, and shoreline for erosion, settlement, and rodent damage Inspect exterior of catch basins AnnuallyAnnuallyAnnually QuarterlyMonthly and after storm events Quarterly and after storm eventsQuarterly, and after storm eventsQuarterly and after storm events Quarterly Inspect ditches, check dams, and all visible pipes and culverts for trash, obstructions and other problems Inspect bioswales for vegetation cover and bare areasInspect fences, gates and locks Quarterly Prepared by RESources for Sustainable Communities for the Birch Bay Watershed & Aquatic Resources Management (BBWARM) District. This project was been funded wholly or in part by the U.S. Environmental Protection Agency under assistance agreement WS-96073401 to Whatcom County. The content of this document do not necessarily reflect the views and policies of the Environmental Protection Agency, nor does mention of trade names or commercial products constitute endorsement or recommendations for use. Inspect pond area for oil sheens or trash Inspect access ramps for ease of heavy equipment access Inspect inside catch basins, including flow restrictor/orifice plate Inspect spillway for vegetation overgrowth and ease of heavy equipment access Inspect interior of catch basins for debris and sediment Pond area sediment accumulation (pond bottom) Inspect pond area for undesirable or poisonous vegetation and noxious weedsInspect water levels in the pondInspect trash racks, debris barriers, and energy dissipaters Inspect inlets and outlets for trash, obstructions, and vegetation Activity Semi-annually, during growing seasonAfter storm events G-5 | Page V:2020-06-23_BILLINGS CLINIC DRAINAGE REPORT 8 (06/23/20) JAZ Appendix D GEOTECHNICAL INVESTIGATION REPORT COVER PAGE Geotechnical Engineering Report __________________________________________________________________________ Billings Clinic Bozeman Campus Bozeman, Montana February 6, 2020 Terracon Project No. 26195068 Prepared for: Billings Clinic Billings, Montana Prepared by: Terracon Consultants, Inc. Billings, Montana Terracon Consultants, Inc. 2110 Overland Avenue, Suite 124 Billings, Montana 59102 P (406) 656 3072 F (406) 656 3578 terracon.com REPORT COVER LETTER TO SIGNFebruary 6, 2020 Billings Clinic PO Box 37000 Billings, Montana 59107-7000 Attn: Mr. Mitch Goplen, FMA, EDAC P:(406) 657 4036 E:mgoplen@billingsclinic.org Re: Geotechnical Engineering Report Billings Clinic Bozeman Campus Westlake Road and East Valley Center Road Bozeman, Montana Terracon Project No. 26195068 Dear Mr. Goplen: We have completed the Geotechnical Engineering services for the above referenced project. This study was performed in general accordance with Terracon Proposal No. P26195068 dated October 21, 2019. This report presents the findings of the subsurface exploration and provides geotechnical recommendations concerning earthwork and the design and construction of foundations and floor slabs for the proposed project. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report or if we may be of further service, please contact us. Sincerely, Terracon Consultants, Inc. Travis Goracke, P.E.Gary W. Rome, P.E. Senior Geotechnical Engineer Senior Project Manager Responsive ■Resourceful ■Reliable 1 REPORT TOPICS INTRODUCTION ............................................................................................................. 1 SITE CONDITIONS ......................................................................................................... 1 PROJECT DESCRIPTION .............................................................................................. 2 GEOTECHNICAL CHARACTERIZATION ...................................................................... 3 EARTHWORK................................................................................................................. 4 SHALLOW FOUNDATIONS ........................................................................................... 8 SEISMIC CONSIDERATIONS ...................................................................................... 10 FLOOR SLABS............................................................................................................. 10 LATERAL EARTH PRESSURES ................................................................................. 12 PAVEMENTS ................................................................................................................ 14 FROST CONSIDERATIONS ......................................................................................... 17 GENERAL COMMENTS ............................................................................................... 17 FIGURES ...................................................................................................................... 19 Note: This report was originally delivered in a web-based format.Orange Bold text in the report indicates a referenced section heading. The PDF version also includes hyperlinks which direct the reader to that section and clicking on the GeoReport logo will bring you back to this page. For more interactive features, please view your project online at client.terracon.com. ATTACHMENTS EXPLORATION AND TESTING PROCEDURES SITE LOCATION AND EXPLORATION PLANS EXPLORATION RESULTS SUPPORTING INFORMATION Note: Refer to each individual Attachment for a listing of contents. Responsive ■Resourceful ■Reliable 1 INTRODUC TION Geotechnical Engineering Report Billings Clinic Bozeman Campus Westlake Road and East Valley Center Road Bozeman, Montana Terracon Project No. 26195068 February 6, 2020 INTRODUCTION This report presents the results of our subsurface exploration and geotechnical engineering services performed for the proposed Billings Clinic Bozeman Campus to be located southwest of the intersection of Westlake Road and East Valley Center Road in Bozeman, Montana. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: ■Subsurface soil conditions ■Foundation design and construction ■Groundwater conditions ■Floor slab design and construction ■Site preparation and earthwork ■Seismic site classification per IBC ■Infiltration rates of subsurface soils ■Lateral earth pressures ■Excavation considerations ■Pavement design and construction ■Frost considerations The geotechnical engineering Scope of Services for this project included the advancement of 5 test borings to depths ranging from approximately 6.5 to 16.5 feet below existing site grades. Maps showing the site and boring locations are shown in the Site Location and Exploration Plan sections, respectively. The results of the laboratory testing performed on soil samples obtained from the site during the field exploration are included on the boring logs and as separate graphs in the Exploration Results section. SITE CONDITIONS The following description of site conditions is derived from our site visit in association with the field exploration and our review of publicly available geologic and topographic maps. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 2 Item Description Parcel Information The project is located Westlake Road and East Valley Center Road in Bozeman, Montana. Latitude/Longitude (approximate) 45.7209° N, 111.0782° W See Site Location Existing Improvements Residential barn and smaller ancillary structures and mass graded land previously cultivated for agricultural use. Current Ground Cover Primarily earthen, lightly- to moderately-vegetated and some areas of aggregate-surface and asphalt paved drives. Existing Topography The site is generally characterized as relatively flat with localized gently to moderately sloping terrain. Elevations are estimated to range from 4,635 to 4,650 feet above mean sea level (MSL). Geology Subsurface conditions consisted of fine-grained clay and/or silt overlying coarse-grained gravel alluvium deposits. PROJECT DESCRIPTION Our initial understanding of the project was provided in our proposal and was discussed during project planning. A period of collaboration has transpired since the project was initiated, and our final understanding of the project conditions is as follows: Item Description Information Provided Project information was provided in a Request for Proposal (RFP) and attachments from Whitten & Borges, PC, via email on October 14, 2019. Project Description Project includes the construction of a new standalone clinic building on a proposed campus site. Proposed Structures The project includes an approximately 30,000 to 40,000 square foot footprint for a three-level structure. Building Construction The structure will consist of steel framing, metal deck, and concrete floors. Wood columns (timber, glue laminated timber, cross-laminated timber) and beams will be used as accents where possible. Building systems are yet to be determined. Maximum Loads (provided by Whitten & Borges) ■Columns: 500 kips or less assuming 30’ x 30’ column layout grid ■Walls: 5 kips per linear foot (klf) ■Slab-on-grade: 150 psf (assumed) Grading/Slopes Finished floor elevation is expected to be at or near existing grade. Site grading plans have not been provided at the time of report preparation; however, minor site grading modification is anticipated to level the site for construction. Below-Grade Structures None anticipated. Free-Standing Retaining Walls Retaining walls are not expected to be constructed as part of site development to achieve final grades. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 3 Item Description Pavements Paved driveway and parking will be constructed on the proposed campus site. Based on the RFP provided by Whitten & Borges, we understand both rigid (concrete) and flexible (asphalt) pavement sections should be considered. Anticipated traffic is as follows: ■Autos/light trucks: <1,000 vehicles per day ■Light delivery, trash collection, ambulatory vehicles: 20 vehicles per week ■Tractor-trailer trucks: 10 vehicles per week The pavement design period is 20 years. GEOTECHNICAL CHARACTERIZATION We have developed a general characterization of the subsurface conditions based upon our review of the subsurface exploration, laboratory data, geologic setting and our understanding of the project. This characterization, termed GeoModel, forms the basis of our geotechnical calculations and evaluation of site preparation and foundation options. Conditions encountered at each exploration point are indicated on the individual logs. The individual logs can be found in the Exploration Results section and the GeoModel can be found in the Figures section of this report. As part of our analyses, we identified the following model layers within the subsurface profile. For a more detailed view of the model layer depths at each boring location, refer to the GeoModel. Model Layer Layer Name General Description 1 Clay Lean clay with varying amounts of silt and sand encountered in all borings. 2 Silt Silt encountered as a discontinuous layer below the clay in boring B-2. 3 Gravel Poorly-graded gravel with varying amounts of silt and sand encountered in borings B-1 to B-3, and B-5. Clay:Clay was encountered at the existing ground surface in all of the borings. The clay extended to depths ranging from approximately 4.5 to 9 feet below existing grade. A representative sample of clay obtained from boring B-3 at approximate depths of 7.5 to 9 feet below existing grade classified as lean clay with sand (CL) in general accordance with the Unified Soil Classification System and ASTM D2487. Penetration resistance values in the clay ranged from 3 to 25 blows per foot, indicating a soft to very stiff soil stratum. Moisture content in the clay ranged from 15 to 31 percent. Liquid and plastic limit testing performed on the representative sample of clay described above indicated a liquid limit of 35 percent and a plastic index of 13. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 4 Moisture-density characteristic (Proctor) testing on a disturbed bulk sample of clay obtained from boring B-4 at approximate depths of 2.6 to 5 feet below existing grade indicated a maximum dry density of 104.9 pounds per cubic foot (pcf) at an optimum moisture content of 17.5 percent. California Bearing Ratio (CBR) testing performed on a disturbed bulk sample of the clay, obtained from boring B-4 and remolded to approximately 95 percent of the maximum dry density per ASTM D698 at optimum moisture, indicated a CBR value of 3.1 percent at 0.1 inch penetration. Silt:Silt was encountered as a discontinuous layer below the clay layer in boring B-2. The silt layer extended to a depth of approximately 9 feet below existing grade. A representative sample of the silt obtained from boring B-2 at approximate depths of 5 to 7 feet below grade classified as silt (ML) in general accordance with the Unified Soil Classification System and ASTM D2487. Penetration resistance values in the silt layer were on the order of 6 blows per foot, indicating a medium stiff soil stratum. Moisture content in the silt was on the order of 20 percent. Liquid and plastic limit testing performed on the representative sample of the silt described above indicated a liquid limit of 30 percent and a plasticity index of 6. One-dimensional consolidation testing of a sample of silt obtained from boring B-2 at approximate depths of 5 to 7 feet indicated a moderate to high compressibility under conditions of wetting and normal loading to 4 kips per square foot (ksf). The dry density of the consolidation sample was 82 pcf. Gravel: Gravel was encountered beneath the clay and silt layers in all of the borings. The gravel layer extended beyond the maximum depth explored of approximately 16.5 feet in borings B-1 to B-3. Although a sample of the gravel obtained from boring B-1 at approximate depths of 10 to 11.5 feet below existing grade classified as a silty sand with gravel (SM), the material visually classified as poorly-graded gravel with silt and sand in general accordance with ASTM D2488. The discrepancy between the visual and laboratory classification is due in large part to the split spoon sampler not being able to accommodate the coarser gravel and cobble in the sampler, thus skewing the laboratory classification. Penetration resistance values in the gravel stratum ranged from 33 to greater than 50 blows per foot, indicating a dense to very dense soil stratum. Unsaturated moisture contents in the gravel ranged from 3 to 13 percent. Groundwater:Groundwater was encountered in borings B-1 to B-3 at a depth of approximately 14 feet at the time of the field investigation. Groundwater elevations are expected to fluctuate with seasonal precipitation, local irrigation practices, and other factors which are beyond the scope of this report. Based on the above, groundwater elevations during construction may vary from those encountered during the field exploration. EARTHWORK Earthwork is anticipated to include clearing and grubbing, excavations, and fill placement. The following sections provide recommendations for use in the preparation of specifications for the Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 5 work. Recommendations include critical quality criteria, as necessary, to render the site in the state considered in our geotechnical engineering evaluation for foundations, floor slabs, and pavements. Site Preparation Prior to placing site fill, existing vegetation and root mat should be removed. Complete stripping of the topsoil should be performed in the proposed building and parking/driveway areas. The pavement subgrade should be proofrolled with an adequately loaded vehicle such as a fully- loaded tandem-axle dump truck. The proofrolling should be performed under the direction of the Geotechnical Engineer. Areas excessively deflecting under the proofroll should be delineated and subsequently addressed by the Geotechnical Engineer. Excessively wet or dry material should either be removed, or moisture conditioned and recompacted. Areas that exhibit deflection during the proofroll should be over-excavated and replaced with granular structural fill. If subsequent proofrolls continue to exhibit deflection, Terracon should be notified for further consultation. Fill Material Types Fill required to achieve design grade should be classified as structural fill and general fill. Structural fill is material used below, or within 10 feet of structures, pavements or constructed slopes. General fill is material used to achieve grade outside of these areas. Earthen materials used for structural and general fill should meet the following material property requirements: Soil Type 1 USCS Classification Acceptable Parameters (for Structural Fill) Granular GW, GP, GM, GC, SW, SP, SM, SC 100% passing 3-inch sieve; 30-60% passing No. 4 sieve; less than 10% passing No. 200 sieve On-Site Soils CL, ML Liquid Limit less than 40. Can be used as backfill outside the building footprint 1.Structural and general fill should consist of approved materials free of organic matter and debris. Frozen material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the Geotechnical Engineer for evaluation prior to use on this site. Fill Compaction Requirements Structural and general fill should meet the following compaction requirements. Item Structural Fill General Fill Maximum Lift Thickness 8 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 Same as Structural fill Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 6 Item Structural Fill General Fill Minimum Compaction Requirements 1, 2, 3 98% of max. below foundations 95% of max. above foundations 95% of max. utility trench backfill, pavement and slab subgrade 92% of max. Water Content Range 1 Low plasticity cohesive: -2% to +2% of optimum Granular: -3% to +3% of optimum As required to achieve min. compaction requirements 1.Maximum density and optimum water content as determined by the standard Proctor test (ASTM D 698). 2.High plasticity cohesive fill should not be compacted to more than 100% of standard Proctor maximum dry density. 3.If the granular material is a coarse sand or gravel, or of a uniform size, or has a low fines content, compaction comparison to relative density may be more appropriate. In this case, granular materials should be compacted to at least 70% relative density (ASTM D 4253 and D 4254). Utility Trench Backfill For low permeability subgrades, utility trenches are a common source of water infiltration and migration. Utility trenches penetrating beneath the building should be effectively sealed to restrict water intrusion and flow through the trenches, which could migrate below the building. The trench should provide an effective trench plug that extends at least 5 feet from the face of the building exterior. The plug material should consist of cementitious flowable fill or low permeability clay. The trench plug material should be placed to surround the utility line. If used, the clay trench plug material should be placed and compacted to comply with the water content and compaction recommendations for structural fill stated previously in this report. Grading and Drainage All grades must provide effective drainage away from the building during and after construction and should be maintained throughout the life of the structure. Water retained next to the building can result in soil movements greater than those discussed in this report. Greater movements can result in unacceptable differential floor slab and/or foundation movements, cracked slabs and walls, and roof leaks. The roof should have gutters/drains with downspouts that discharge onto splash blocks at a distance of at least 10 feet from the building. Exposed ground should be sloped and maintained at a minimum 5% away from the building for at least 10 feet beyond the perimeter of the building. Locally, flatter grades may be necessary to transition ADA access requirements for flatwork. After building construction and landscaping have been completed, final grades should be verified to document effective drainage has been achieved. Grades around the structure should also be periodically inspected and adjusted, as necessary, as part of the structure’s maintenance program. Where paving or flatwork abuts the structure, a maintenance program should be established to effectively seal and maintain joints and prevent surface water infiltration. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 7 Earthwork Construction Considerations Shallow excavations for the proposed structure are anticipated to be accomplished with conventional construction equipment. Upon completion of filling and grading, care should be taken to maintain the subgrade water content prior to construction of floor slabs. Construction traffic over the completed subgrades should be avoided. The site should also be graded to prevent ponding of surface water on the prepared subgrades or in excavations. Water collecting over or adjacent to construction areas should be removed. If the subgrade freezes, desiccates, saturates, or is disturbed, the affected material should be removed, or the materials should be scarified, moisture conditioned, and recompacted prior to construction. As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926, Subpart P, “Excavations” and its appendices, and in accordance with any applicable local, and/or state regulations. Construction site safety is the sole responsibility of the contractor who controls the means, methods, and sequencing of construction operations. Under no circumstances shall the information provided herein be interpreted to mean Terracon is assuming responsibility for construction site safety, or the contractor's activities; such responsibility shall neither be implied nor inferred. Construction Observation and Testing The earthwork efforts should be monitored under the direction of the Geotechnical Engineer. Monitoring should include documentation of adequate removal of vegetation and topsoil, proofrolling, and mitigation of areas delineated by the proofroll to require mitigation. Each lift of compacted fill should be tested, evaluated, and reworked, as necessary, until approved by the Geotechnical Engineer prior to placement of additional lifts. Each lift of fill should be tested for density and water content at a frequency of at least one test for every 2,500 square feet of compacted fill in the building areas and 5,000 square feet in pavement areas. One density and water content test should be performed for every 50 linear feet of compacted utility trench backfill. In areas of foundation excavations, the bearing subgrade should be evaluated under the direction of the Geotechnical Engineer. If unanticipated conditions are encountered, the Geotechnical Engineer should prescribe mitigation options. In addition to the documentation of the essential parameters necessary for construction, the continuation of the Geotechnical Engineer into the construction phase of the project provides the continuity to maintain the Geotechnical Engineer’s evaluation of subsurface conditions, including assessing variations and associated design changes. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 8 SHALLOW FOUNDATIONS If the site has been prepared in accordance with the requirements noted in Earthwork, the following design parameters are applicable for shallow foundations. Design Parameters – Compressive Loads Item Description Maximum Net Allowable Bearing pressure 1, 2 5,000 psf Required Bearing Stratum 3 A zone of granular structural fill extending to natural gravel. Minimum Foundation Dimensions Columns:30 inches Continuous: 18 inches Ultimate Coefficient of Sliding Friction 4 0.70 (granular structural fill) Minimum Embedment below Finished Grade 5 Exterior footings in unheated areas:48 inches Interior footings in heated areas:24 inches Estimated Total Settlement from Structural Loads 2 Less than about 1 inch Estimated Differential Settlement 2, 6 About 1/2 of total settlement 1.The maximum net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. An appropriate factor of safety has been applied. Values assume that exterior grades are no steeper than 20% within 10 feet of structure. 2.Values provided are for maximum loads noted in Project Description. 3.Unsuitable or soft soils should be over-excavated and replaced per the recommendations presented in the Earthwork. 4.Can be used to compute sliding resistance where foundations are placed on suitable soil/materials. Should be neglected for foundations subject to net uplift conditions. 5.Embedment necessary to minimize the effects of frost and/or seasonal water content variations. For sloping ground, maintain depth below the lowest adjacent exterior grade within 5 horizontal feet of the structure. 6.Differential settlements are as measured over a span of 50 feet. Design Parameters - Uplift Loads Uplift resistance of spread footings can be developed from the effective weight of the footing and the overlying soils. As illustrated on the subsequent figure, the effective weight of the soil prism defined by diagonal planes extending up from the top of the perimeter of the foundation to the ground surface at an angle, q, of 20 degrees from the vertical can be included in uplift resistance. The maximum allowable uplift capacity should be taken as a sum of the effective weight of soil plus the dead weight of the foundation, divided by an appropriate factor of safety. A maximum total unit weight of 125 pcf should be used for granular structural backfill. This unit weight should be reduced to 60 pcf for portions of the backfill below the groundwater elevation. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 9 Foundation Construction Considerations As noted in Earthwork, the footing excavations should be evaluated under the direction of the Geotechnical Engineer. The base of all foundation excavations should be free of water and loose soil, prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing soil disturbance. Care should be taken to prevent wetting or drying of the bearing materials during construction. Excessively wet or dry material or any loose/disturbed material in the bottom of the footing excavations should be removed/reconditioned before foundation concrete is placed. If unsuitable bearing soils are encountered at the base of the planned footing excavation, the excavation should be extended deeper to suitable soils, and the footings could bear directly on these soils at the lower level or on lean concrete backfill placed in the excavations. This is illustrated on the sketch below. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 10 Over-excavation for structural fill placement below footings should be conducted as shown below. The over-excavation should be backfilled up to the footing base elevation, with granular structural fill placed, as recommended in the Earthwork section. SEISMIC CONSIDERATIONS The seismic design requirements for buildings and other structures are based on Seismic Design Category. Site Classification is required to determine the Seismic Design Category for a structure. The Site Classification is based on the upper 100 feet of the site profile defined by a weighted average value of either shear wave velocity, standard penetration resistance, or undrained shear strength in accordance with Section 20.4 of ASCE 7 and the International Building Code (IBC). Based on the soil properties encountered at the site and as described on the exploration logs and results, it is our professional opinion that the Seismic Site Classification is C. Subsurface explorations at this site were extended to a maximum depth of 16.5 feet. The site properties below the boring depth to 100 feet were estimated based on our experience and knowledge of geologic conditions of the general area. Additional deeper borings or geophysical testing may be performed to confirm the conditions below the current boring depth. FLOOR SLABS Depending upon the finished floor elevation, unsuitable, weak, soft to very stiff soils may be encountered at the floor slab subgrade level. These soils should be replaced with structural fill, so the floor slab is supported on at least 3 feet of compacted granular structural fill. To improve constructability and limit the infiltration of fines into the granular layer, a Mirafi 180N or equivalent separation fabric should be placed at the fine-grained soil/granular structural fill interface. Design parameters for floor slabs assume the requirements for Earthwork have been followed. Specific attention should be given to positive drainage away from the structure and positive drainage of the aggregate base beneath the floor slab. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 11 Floor Slab Design Parameters Item Description Floor Slab Support 1 Minimum 36 inches of granular structural fill compacted to at least 95% of ASTM D 698 2, 3 Estimated Modulus of Subgrade Reaction 2 250 pounds per square inch per inch (psi/in) for point loads 1.Floor slabs should be structurally independent of building footings or walls to reduce the possibility of floor slab cracking caused by differential movements between the slab and foundation. 2.Modulus of subgrade reaction is an estimated value based upon our experience with the subgrade condition, the requirements noted in Earthwork, and the floor slab support as noted in this table. It is provided for point loads. For large area loads the modulus of subgrade reaction would be lower. 3.Other design considerations such as cold temperatures and condensation development could warrant more extensive design provisions. The use of a vapor retarder should be considered beneath concrete slabs on grade covered with wood, tile, carpet, or other moisture sensitive or impervious coverings, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer should refer to ACI 302 and/or ACI 360 for procedures and cautions regarding the use and placement of a vapor retarder. Saw-cut control joints should be placed in the slab to help control the location and extent of cracking. For additional recommendations refer to the ACI Design Manual. Joints or cracks should be sealed with a water-proof, non-extruding compressible compound specifically recommended for heavy duty concrete pavement and wet environments. Where floor slabs are tied to perimeter walls or turn-down slabs to meet structural or other construction objectives, our experience indicates differential movement between the walls and slabs will likely be observed in adjacent slab expansion joints or floor slab cracks beyond the length of the structural dowels. The Structural Engineer should account for potential differential settlement through use of sufficient control joints, appropriate reinforcing or other means. Floor Slab Construction Considerations Finished subgrade, within and for at least 10 feet beyond the floor slab, should be protected from traffic, rutting, or other disturbance and maintained in a relatively moist condition until floor slabs are constructed. If the subgrade should become damaged or desiccated prior to construction of floor slabs, the affected material should be removed, and structural fill should be added to replace the resulting excavation. Final conditioning of the finished subgrade should be performed immediately prior to placement of the floor slab support course. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 12 The Geotechnical Engineer should approve the condition of the floor slab subgrades immediately prior to placement of the floor slab support course, reinforcing steel, and concrete. Attention should be paid to high traffic areas that were rutted and disturbed earlier, and to areas where backfilled trenches are located. LATERAL EARTH PRESSURES Design Parameters Structures with unbalanced backfill levels on opposite sides should be designed for earth pressures at least equal to values 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 in the diagram below. 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 (unless stated). Lateral Earth Pressure Design Parameters Earth Pressure Condition 1 Coefficient for Backfill Type2 Surcharge Pressure 3, 4, 5 p1 (psf) Effective Fluid Pressures (psf)2, 4, 5 Unsaturated 6 Submerged 6 Active (Ka)Granular - 0.27 Fine Grained - 0.49 (0.27)S (0.49)S (35)H (55)H (80)H (85)H At-Rest (Ko)Granular - 0.43 Fine Grained - 0.66 (0.43)S (0.66)S (55)H (70)H (90)H (95)H Passive (Kp)Granular - 3.69 Fine Grained - 2.04 --- --- (460)H (225)H (315)H (160)H Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 13 Lateral Earth Pressure Design Parameters Earth Pressure Condition 1 Coefficient for Backfill Type2 Surcharge Pressure 3, 4, 5 p1 (psf) Effective Fluid Pressures (psf)2, 4, 5 Unsaturated 6 Submerged 6 1.For active earth pressure, wall must rotate about base, with top lateral movements 0.002 H to 0.004 H, where H is wall height. For passive earth pressure, wall must move horizontally to mobilize resistance. 2.Uniform, horizontal backfill, compacted to at least 95% of the ASTM D 698 maximum dry density, rendering a maximum unit weight of 125 pcf and an angle of internal friction of 35° for granular structural fill; a maximum unit weight of 110 pcf and an angle of internal friction of 20° was estimated for fine-grained on- site soils. 3.Uniform surcharge, where S is surcharge pressure. 4.Loading from heavy compaction equipment is not included. 5.No safety factor is included in these values. 6.To achieve “Unsaturated” conditions, follow guidelines in Subsurface Drainage for Below-Grade Walls below. “Submerged” conditions are recommended when drainage behind walls is not incorporated into the design. Backfill placed against structures should consist of granular soils or low plasticity cohesive soils. For the granular values to be valid, the granular backfill must extend out and up from the base of the wall at an angle of at least 45 and 60 degrees from vertical for the active and passive cases, respectively. Subsurface Drainage for Below-Grade Walls A perforated rigid plastic drain line installed behind the base of walls and extends below adjacent grade is recommended to prevent hydrostatic loading on the walls. The invert of a drain line around a below-grade building area or exterior retaining wall should be placed near foundation bearing level. The drain line should be sloped to provide positive gravity drainage to daylight or to a sump pit and pump. The drain line should be surrounded by clean, free-draining granular material having less than 5% passing the No. 200 sieve, such as ASTM No. 57 aggregate. The free-draining aggregate should be encapsulated in a filter fabric. The granular fill should extend to within 2 feet of final grade, where it should be capped with compacted cohesive fill to reduce infiltration of surface water into the drain system. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 14 As an alternative to free-draining granular fill, a pre-fabricated drainage structure may be used. A pre-fabricated drainage structure is a plastic drainage core or mesh which is covered with filter fabric to prevent soil intrusion, and is fastened to the wall prior to placing backfill. PAVEMENTS General Pavement Comments Pavement designs are provided for the traffic conditions and pavement life conditions as noted in Project Description and in the following sections of this report. A critical aspect of pavement performance is site preparation. Pavement designs noted in this section must be applied to the site which has been prepared as recommended in the Earthwork section. We anticipated the onsite soils will be utilized in subgrade construction. A California Bearing Ratio (CBR) test has been performed on a disturbed bulk sample of the clay subgrade obtained from boring B-4 at approximate depths of 2.6 to 5 feet below existing grade. This material was compacted at about 95 percent of the standard proctor maximum dry density at approximately optimum moisture. The moisture-density relationship and CBR test results are presented in the Exploration Results section. Support characteristics of subgrade for pavement design do not account for shrink/swell movements of an expansive clay subgrade, such as soils encountered on this project. Thus, the pavement may be adequate from a structural standpoint, yet still experience cracking and deformation due to shrink/swell related movement of the subgrade. Pavement Design Parameters A subgrade CBR of 3 was used for the AC pavement designs, and a modulus of subgrade reaction of 100 pci was used for the PCC pavement designs. The values were empirically derived based upon our experience with the lean clay subgrade soils and our understanding of the quality of the Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 15 subgrade as prescribed by the Site Preparation conditions as outlined in Earthwork. A modulus of rupture of 580 psi was used for pavement concrete. Pavement design recommendations for this project have been based on procedures outlined in the AASHTO Guide for Design of Pavement Structures, 1993, coupled with publications by the Asphalt Institute and the American Concrete Institute on the design of parking lots and our local experience. Pavement design input parameters and resulting pavement sections are provided in the following table: Pavement Thickness Design Parameters Input Parameter Flexible (asphalt)Rigid (concrete) Reliability 85 85 Initial Serviceability 4.2 4.5 Terminal Serviceability 2.0 2.5 Standard Deviation 0.45 0.35 Drainage 0.9 0.9 Design ESAL Value: Anticipated Traffic 120,000 145,000 Pavement Section Thicknesses The following table provides options for AC and PCC Sections: Asphaltic Concrete Design Traffic Area Asphalt Concrete (in.)1 Aggregate Base (in.)2 Total Thickness (in.)1 Light Duty Parking 3 9 12 Heavy Duty Drive Lanes 4 9 13 1.Asphalt concrete should conform to Montana Public Works Standard Specifications (MPWSS) requirements. 2.Aggregate base should meet the requirements for 1-1/2 inch crushed aggregate in accordance with MPWSS Section 02235. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 16 Portland Cement Concrete Design Traffic Area Portland Cement Concrete (in.)1 Aggregate Base (in.)2 Total Thickness (in.) Light Duty Parking 5 6 11 Heavy Duty Drive Lanes 6 6 12 1.Portland cement concrete should conform to MPWSS requirements. 2.Aggregate base should meet the requirements for 1-1/2 inch crushed aggregate in accordance with MPWSS Section 02235 Migration of fines into the aggregate base course layer will reduce the support characteristics of the base and decrease performance of the pavement section. The placement of a geotextile separation fabric, such as a Mirafi 180N or equivalent, between the fine-grained subgrade and the aggregate base course to improve constructability and extend the pavement’s service life should be considered for the above sections. Pavement Drainage Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond on or adjacent to the pavements could saturate the subgrade and contribute to premature pavement deterioration. In addition, the pavement subgrade should be graded to provide positive drainage within the granular base section. Appropriate sub-drainage or connection to a suitable daylight outlet should be provided to remove water from the granular subbase. Pavement Maintenance The pavement sections represent minimum recommended thicknesses and, as such, periodic maintenance should be anticipated. Therefore, preventive maintenance should be planned and provided for through an on-going pavement management program. Maintenance activities are intended to slow the rate of pavement deterioration and to preserve the pavement investment. Maintenance consists of both localized maintenance (e.g., crack and joint sealing and patching) and global maintenance (e.g., surface sealing). Preventive maintenance is usually the priority when implementing a pavement maintenance program. Additional engineering observation is recommended to determine the type and extent of a cost-effective program. Even with periodic maintenance, some movements and related cracking may still occur and repairs may be required. 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: Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 17 ■Final grade adjacent to paved areas should slope down from the edges at a minimum 2%. ■Subgrade and pavement surfaces should have a minimum 2% slope to promote proper surface drainage. ■Install below pavement drainage systems 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. ■Place compacted, low permeability backfill against the exterior side of curb and gutter. ■Place curb, gutter and/or sidewalk directly on clay subgrade soils rather than on unbound granular base course materials. FROST CONSIDERATIONS The soils on this site are frost susceptible, and small amounts of water can affect the performance of the slabs on-grade, sidewalks, and pavements. Exterior slabs should be anticipated to heave during winter months. If frost action needs to be eliminated in critical areas, we recommend the use of non-frost susceptible (NFS) fill or structural slabs (for instance, structural stoops in front of building doors). Placement of NFS material in large areas may not be feasible; however, the following recommendations are provided to help reduce potential frost heave: ■Provide surface drainage away from the building and slabs, and toward the site storm drainage system. ■Install drains around the perimeter of the building, stoops, below exterior slabs and pavements, and connect them to the storm drainage system. ■Grade clayey subgrades, so groundwater potentially perched in overlying more permeable subgrades, such as sand or aggregate base, slope toward a site drainage system. ■Place NFS fill as backfill beneath slabs and pavements critical to the project. ■Place a 3 horizontal to 1 vertical (3H:1V) transition zone between NFS fill and other soils. ■Place NFS materials in critical sidewalk areas. As an alternative to extending NFS fill to the full frost depth, consideration can be made to placing extruded polystyrene or cellular concrete under a buffer of at least 2 feet of NFS material. GENERAL COMMENTS Our analysis and opinions are based upon our understanding of the project, the geotechnical conditions in the area, and the data obtained from our site exploration. Natural variations will occur between exploration point locations 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. Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable 18 Terracon should be retained as the Geotechnical Engineer, where noted in this report, to provide observation and testing services during pertinent construction phases. If variations appear, we can provide further evaluation and supplemental recommendations. If variations are noted in the absence of our observation and testing services on-site, we should be immediately notified so that we can provide evaluation and supplemental recommendations. Our Scope of Services does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, 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. Our services and any correspondence or collaboration through this system are intended for the sole benefit and exclusive use of our client for specific application to the project discussed and are accomplished in accordance with generally accepted geotechnical engineering practices with no third-party beneficiaries intended. Any third-party access to services or correspondence is solely for information purposes to support the services provided by Terracon to our client. Reliance upon the services and any work product is limited to our client, and is not intended for third parties. Any use or reliance of the provided information by third parties is done solely at their own risk. No warranties, either express or implied, are intended or made. Site characteristics as provided are for design purposes and not to estimate excavation cost. Any use of our report in that regard is done at the sole risk of the excavating cost estimator as there may be variations on the site that are not apparent in the data that could significantly impact excavation cost. Any parties charged with estimating excavation costs should seek their own site characterization for specific purposes to obtain the specific level of detail necessary for costing. Site safety, and cost estimating including, excavation support, and dewatering requirements/design are the responsibility of others. If changes in the nature, design, or location of the project are planned, our conclusions and recommendations shall not be considered valid unless we review the changes and either verify or modify our conclusions in writing. Responsive ■Resourceful ■Reliable FIGURES Contents: GeoModel 0 2 4 6 8 10 12 14 16 18 DE P T H B E L O W G R A D E ( F e e t ) Billings Clinic Bozeman Campus Bozeman, MTTerracon Project No. 26195068 Layering shown on this figure has been developed by the geotechnical engineer for purposes of modeling the subsurface conditions asrequired for the subsequent geotechnical engineering for this project.Numbers adjacent to soil column indicate depth below ground surface. NOTES: B-1 B-2 B-3 B-4 B-5 GEOMODEL This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions. Groundwater levels are temporal. The levels shown are representative of the dateand time of our exploration. Significant changes are possible over time.Water levels shown are as measured during and/or after drilling. In some cases, boring advancement methods mask the presence/absence of groundwater. Seeindividual logs for details. First Water Observation Poorly-graded gravel with varying amounts of silt and sandencountered in borings B-1 to B-3, and B-5.3 LEGEND Lean Clay Poorly-graded Gravel withSilt and Sand Silt Lean Clay with Sand Model Layer General DescriptionLayer Name Lean clay with varying amounts of silt and sand encounteredin all borings.1 Silt encountered as a discontinuous layer below the clay inboring B-2.2 Gravel Clay Silt 8 16.5 1 3 14 5 9 16.5 1 2 3 14 9 16.5 1 3 14 6.5 1 4.5 6.5 1 3 Responsive ■Resourceful ■Reliable ATTACHMENTS Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 1 of 5 EXPLORATION AND TESTING PROCEDURES Field Exploration Number of Borings Boring Depth (feet)Planned Location 3 16.5 Planned Building Footprint 2 6.5 Paved Parking Area Boring Layout and Elevations: Terracon personnel provided the boring layout based on a preliminary site layout provided by CTA Architects Engineers. Coordinates were obtained with a handheld GPS unit (estimated horizontal accuracy of about ±10 feet). If elevations and a more precise boring layout are desired, we recommend borings be surveyed following completion of fieldwork. Subsurface Exploration Procedures: We advanced the borings with a truck-mounted rotary drill rig using continuous-flight, hollow-stem augers. Four samples were obtained in the upper 10 feet of each building boring and at intervals of 5 feet thereafter. In the thin-walled tube sampling procedure, a thin-walled, seamless steel tube with a sharp cutting edge was pushed hydraulically into the soil to obtain a relatively undisturbed sample. In the split-barrel sampling procedure, a standard 2-inch outer diameter split-barrel sampling spoon was driven into the ground by a 140-pound automatic hammer falling a distance of 30 inches. The number of blows required to advance the sampling spoon the last 12 inches of a normal 18-inch penetration is recorded as the Standard Penetration Test (SPT) resistance value. The SPT resistance values, also referred to as N-values, are indicated on the boring logs at the test depths. We observed and recorded groundwater levels during drilling and sampling. For safety purposes, all borings were backfilled with auger cuttings after their completion. The sampling depths, penetration distances, and other sampling information was recorded on the field boring logs. The samples were placed in appropriate containers and taken to our soil laboratory for testing and classification by a Geotechnical Engineer. Our exploration team prepared field boring logs as part of the drilling operations. These field logs included visual classifications of the materials encountered during drilling and our interpretation of the subsurface conditions between samples. Final boring logs were prepared from the field logs. The final boring logs represent the Geotechnical Engineer's interpretation of the field logs and include modifications based on observations and tests of the samples in our laboratory. Field Infiltration Testing: As requested by CTA Architects Engineers, Terracon performed field testing to determine the rate at which water would infiltrate into the site soils. Based on our discussion with CTA at the time of testing, a final location of the infiltration basin had not been determined; however, it was anticipated to be located beneath the proposed parking lot and would extend to the natural gravel stratum. Terracon selected three locations west of the proposed Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 2 of 5 building within the paved parking lot section for testing. The drill rig was used to excavate an approximate 8-inch diameter hole at each proposed test location (marked I-1 to I-3 on the Exploration Plan) to a depth of approximately 10 feet below existing grade, into the natural gravel stratum. The sides and bottom of each hole were roughened and cleaned out. A 2-inch perforated PVC pipe was placed in each hole. Washed rock was placed in the annular space of the bottom 2 feet, between the PVC pipe and the walls of the hole. Each infiltration test hole was pre-soaked with approximately 12 inches of water prior to running the tests. Prior to beginning each test, the PVC casing was filled with water to a depth of approximately 6 to 12 inches and water level measurements were taken over an hour to determine the rate of infiltration. The raw field data is presented below to facilitate design of stormwater infiltration/retention features for the project site. Test Start Time Stop Time Initial Distance Below Reference Final Distance Below Reference (ft) Water Level Drop (ft.) Infiltration, min/in. I-1, test 1 11:15 11:25 8.96 9.27 0.31 0.37 11:25 11:35 9.27 9.45 0.18 0.22 11:35 11:45 9.45 9.56 0.11 0.13 11:45 11:55 9.56 9.72 0.16 0.19 11:55 12:05 9.72 9.85 0.13 0.16 12:05 12:15 9.85 9.92 0.07 0.08 I-1, test 2 13:05 13:15 9.58 9.73 0.15 0.18 13:15 13:25 9.73 9.82 0.09 0.11 13:25 13:35 9.82 9.94 0.12 0.14 13:35 13:45 9.94 9.95 0.01 0.01 13:45 13:55 9.95 10.00 0.05**0.06 **water level dropped below bottom of casing and test was stopped Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 3 of 5 Test Start Time Stop Time Initial Distance Below Reference Final Distance Below Reference (ft) Water Level Drop (ft.) Infiltration, min/in. I-2, test 1 11:25 11:35 9.26 9.57 0.31 0.37 11:35 11:45 9.57 9.71 0.14 0.17 11:45 11:55 9.71 9.80 0.09 0.11 11:55 12:05 9.80 9.90 0.10 0.12 12:05 12:15 9.90 9.94 0.04 0.05 12:15 12:25 9.94 9.97 0.03 0.04 I-2, test 2 13:10 13:20 9.59 9.78 0.19 0.23 13:20 13:30 9.78 9.87 0.09 0.11 13:30 13:40 9.87 9.95 0.08**0.10 **water level dropped below bottom of casing and test was stopped Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 4 of 5 Test Start Time Stop Time Initial Distance Below Reference Final Distance Below Reference (ft) Water Level Drop (ft.) Infiltration, min/in. I-3, test 1 11:35 11:45 9.06 9.12 0.06 0.07 11:45 11:55 9.12 9.16 0.04 0.05 11:55 12:05 9.16 9.19 0.03 0.04 12:05 12:15 9.19 9.20 0.01 0.01 12:15 12:25 9.20 9.22 0.02 0.02 12:25 12:35 9.22 9.23 0.01 0.01 I-3, test 2 13:14 13:24 9.30 9.34 0.04 0.05 13:24 13:34 9.34 9.35 0.01 0.01 13:34 13:44 9.35 9.37 0.02 0.02 13:44 13:54 9.37 9.39 0.02 0.02 13:54 14:04 9.39 9.42 0.03 0.04 14:04 14:14 9.42 9.44 0.02 0.02 Laboratory Testing The project engineer reviewed the field data and assigned laboratory tests to better understand the engineering properties of the various soil strata, as necessary, for this project. Procedural standards noted below are for reference to methodology in general. In some cases, variations to methods were applied because of local practice or professional judgment. Standards noted below include reference to other, related standards. Such references are not necessarily applicable to describe the specific test performed. ■ASTM D2216 Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass ■ASTM D4318 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils ■ASTM D422 Standard Test Method for Particle-Size Analysis of Soils ■ASTM D2435/D2435M Standard Test Methods for One-Dimensional Consolidation Properties of Soils Using Incremental Loading Geotechnical Engineering Report Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 5 of 5 ■ASTM D698 Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort ■ASTM D1883 Standard Test Method for California Bearing Ratio (CBR) of Laboratory- Compacted Soils ■Resistivity, pH, and soluble sulfate content The laboratory testing program included examination of soil samples by an engineer. Based on the material’s texture and plasticity, we described and classified the soil samples in accordance with the Unified Soil Classification System. Chemical Analysis:A soil sample obtained from boring B-1 at an approximate depth of 0 to 1.5 feet was submitted to Energy Laboratories for chemical analysis, to include the determination of the soils’ pH, soluble sulfate content, and resistivity. These chemical analyses are currently still in progress at the time of report preparation. We will forward the results of the analyses as they become available. Responsive ■Resourceful ■Reliable SITE LOCATION AND EXPLORATION PLANS Contents: Site Location Plan Exploration Plan Note: All attachments are one page unless noted above. SITE LOCATION Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Note to Preparer: This is a large table with outside borders. Just click inside the table above this text box, then paste your GIS Toolbox image. When paragraph markers are turned on you may notice a line of hidden text above and outside the table – please leave that alone. Limit editing to inside the table. The line at the bottom about the general location is a separate table line. You can edit it as desired, but try to keep to a single line of text to avoid reformatting the page. SITE LOCA TION DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS EXPLORATION PLAN Billings Clinic Bozeman Campus ■ Bozeman, Montana February 6, 2020 ■ Terracon Project No. 26195068 Note to Preparer: This is a large table with outside borders. Just click inside the table above this text box, then paste your GIS Toolbox image. When paragraph markers are turned on you may notice a line of hidden text above and outside the table – please leave that alone. Limit editing to inside the table. The line at the bottom about the general location is a separate table line. You can edit it as desired, but try to keep to a single line of text to avoid reformatting the page. EXPLORATION P LAN DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS EXPLORATION RESULTS Contents: Boring Logs (B-1 through B-5) Atterberg Limits Grain Size Distribution Consolidation/Swell Moisture Density Relationship CBR Note: All attachments are one page unless noted above. 11-11-8 N=19 3-2-2N=4 3-4-5N=9 17-27-39N=66 50/2" 30 23 22 23 NP LEAN CLAY (CL), brown, moist, medium stiff to very stiff POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM),with cobbles and boulders, fine to coarse grained, rounded tosubrounded, brown, moist to wet, very dense Boring Terminated at 16.5 Feet 8.0 16.5 Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual. TH I S B O R I N G L O G I S N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . G E O S M A R T L O G - N O W E L L 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 WA T E R L E V E L OB S E R V A T I O N S DE P T H ( F t . ) 5 10 15 FI E L D T E S T RE S U L T S UN C O N F I N E D CO M P R E S S I V E ST R E N G T H ( p s f ) PE R C E N T F I N E S WA T E R CO N T E N T ( % ) DR Y U N I T WE I G H T ( p c f ) ATTERBERGLIMITS LL-PL-PI LOCATION See Exploration Plan Latitude: 45.7212° Longitude: -111.0791° GR A P H I C L O G MO D E L L A Y E R DEPTH Page 1 of 1 Advancement Method:Hollow-stem auger Abandonment Method:Boring backfilled with auger cuttings upon completion. Notes: Project No.: 26195068 Drill Rig: BK-81 BORING LOG NO. B-1 Billings ClinicCLIENT:Billings, MT Driller: HazTech Boring Completed: 01-14-2020 PROJECT: Billings Clinic Bozeman Campus See Exploration and Testing Procedures for adescription of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation ofsymbols and abbreviations. Westlake Road & East Valley Center Road Bozeman, MT SITE: Boring Started: 01-14-2020 2110 Overland Ave, Ste 124Billings, MT While drilling WATER LEVEL OBSERVATIONS 1 3 SA M P L E T Y P E 9-10-7 N=17 3-3-2N=5 3-2-4N=6 13-13-20N=33 24-33-35N=68 94 31 21 20 20 3 82 30-24-6 LEAN CLAY (CL), brown, moist, medium stiff to very stiff SILT (ML), brown, moist, medium stiff POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), with cobbles and boulders, fine to coarse grained, rounded tosubrounded, brown, moist to wet, dense to very dense Boring Terminated at 16.5 Feet 5.0 9.0 16.5 Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual. TH I S B O R I N G L O G I S N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . G E O S M A R T L O G - N O W E L L 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 WA T E R L E V E L OB S E R V A T I O N S DE P T H ( F t . ) 5 10 15 FI E L D T E S T RE S U L T S UN C O N F I N E D CO M P R E S S I V E ST R E N G T H ( p s f ) PE R C E N T F I N E S WA T E R CO N T E N T ( % ) DR Y U N I T WE I G H T ( p c f ) ATTERBERGLIMITS LL-PL-PI LOCATION See Exploration Plan Latitude: 45.7212° Longitude: -111.0775° GR A P H I C L O G MO D E L L A Y E R DEPTH Page 1 of 1 Advancement Method:Hollow-stem auger Abandonment Method:Boring backfilled with auger cuttings upon completion. Notes: Project No.: 26195068 Drill Rig: BK-81 BORING LOG NO. B-2 Billings ClinicCLIENT:Billings, MT Driller: HazTech Boring Completed: 01-14-2020 PROJECT: Billings Clinic Bozeman Campus See Exploration and Testing Procedures for adescription of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation ofsymbols and abbreviations. Westlake Road & East Valley Center Road Bozeman, MT SITE: Boring Started: 01-14-2020 2110 Overland Ave, Ste 124Billings, MT While drilling WATER LEVEL OBSERVATIONS 1 2 3 SA M P L E T Y P E 13-14-11 N=25 2-2-2 N=4 3-3-8 N=11 26-34-30N=64 20-17-20N=37 77 25 20 4 35-22-13 LEAN CLAY WITH SAND (CL), brown, moist, medium stiff tovery stiff POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM), with cobbles and boulders, fine to coarse grained, rounded tosubrounded, brown, moist to wet, dense to very dense Boring Terminated at 16.5 Feet 9.0 16.5 Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual. TH I S B O R I N G L O G I S N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . G E O S M A R T L O G - N O W E L L 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 WA T E R L E V E L OB S E R V A T I O N S DE P T H ( F t . ) 5 10 15 FI E L D T E S T RE S U L T S UN C O N F I N E D CO M P R E S S I V E ST R E N G T H ( p s f ) PE R C E N T F I N E S WA T E R CO N T E N T ( % ) DR Y U N I T WE I G H T ( p c f ) ATTERBERGLIMITS LL-PL-PI LOCATION See Exploration Plan Latitude: 45.7212° Longitude: -111.0783° GR A P H I C L O G MO D E L L A Y E R DEPTH Page 1 of 1 Advancement Method:Hollow-stem auger Abandonment Method:Boring backfilled with auger cuttings upon completion. Notes: Project No.: 26195068 Drill Rig: BK-81 BORING LOG NO. B-3 Billings ClinicCLIENT:Billings, MT Driller: HazTech Boring Completed: 01-14-2020 PROJECT: Billings Clinic Bozeman Campus See Exploration and Testing Procedures for adescription of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation ofsymbols and abbreviations. Westlake Road & East Valley Center Road Bozeman, MT SITE: Boring Started: 01-14-2020 2110 Overland Ave, Ste 124Billings, MT While drilling WATER LEVEL OBSERVATIONS 1 3 SA M P L E T Y P E 12-11-6 N=17 2-3-3N=6 3-3-3 N=6 24 18 21 LEAN CLAY (CL), brown, moist, medium stiff to very stiff Boring Terminated at 6.5 Feet 6.5 Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual. TH I S B O R I N G L O G I S N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . G E O S M A R T L O G - N O W E L L 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 WA T E R L E V E L OB S E R V A T I O N S DE P T H ( F t . ) 5 FI E L D T E S T RE S U L T S UN C O N F I N E D CO M P R E S S I V E ST R E N G T H ( p s f ) PE R C E N T F I N E S WA T E R CO N T E N T ( % ) DR Y U N I T WE I G H T ( p c f ) ATTERBERGLIMITS LL-PL-PI LOCATION See Exploration Plan Latitude: 45.7217° Longitude: -111.0795° GR A P H I C L O G MO D E L L A Y E R DEPTH Page 1 of 1 Advancement Method:Hollow-stem auger Abandonment Method:Boring backfilled with auger cuttings upon completion. Notes: Project No.: 26195068 Drill Rig: BK-81 BORING LOG NO. B-4 Billings ClinicCLIENT:Billings, MT Driller: HazTech Boring Completed: 01-14-2020 PROJECT: Billings Clinic Bozeman Campus See Exploration and Testing Procedures for adescription of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation ofsymbols and abbreviations. Westlake Road & East Valley Center Road Bozeman, MT SITE: Boring Started: 01-14-2020 2110 Overland Ave, Ste 124Billings, MT WATER LEVEL OBSERVATIONS Groundwater not encountered 1 SA M P L E T Y P E 11-11-6 N=17 3-1-2N=3 4-5-23 N=28 26 15 13 LEAN CLAY (CL), brown, moist, soft to very stiff POORLY GRADED GRAVEL WITH SILT AND SAND (GP-GM),with cobbles and boulders, fine to coarse grained, rounded tosubrounded, brown, moist, medium dense Boring Terminated at 6.5 Feet 4.5 6.5 Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual. TH I S B O R I N G L O G I S N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . G E O S M A R T L O G - N O W E L L 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 WA T E R L E V E L OB S E R V A T I O N S DE P T H ( F t . ) 5 FI E L D T E S T RE S U L T S UN C O N F I N E D CO M P R E S S I V E ST R E N G T H ( p s f ) PE R C E N T F I N E S WA T E R CO N T E N T ( % ) DR Y U N I T WE I G H T ( p c f ) ATTERBERGLIMITS LL-PL-PI LOCATION See Exploration Plan Latitude: 45.7205° Longitude: -111.0797° GR A P H I C L O G MO D E L L A Y E R DEPTH Page 1 of 1 Advancement Method:Hollow-stem auger Abandonment Method:Boring backfilled with auger cuttings upon completion. Notes: Project No.: 26195068 Drill Rig: BK-81 BORING LOG NO. B-5 Billings ClinicCLIENT:Billings, MT Driller: HazTech Boring Completed: 01-14-2020 PROJECT: Billings Clinic Bozeman Campus See Exploration and Testing Procedures for adescription of field and laboratory proceduresused and additional data (If any). See Supporting Information for explanation ofsymbols and abbreviations. Westlake Road & East Valley Center Road Bozeman, MT SITE: Boring Started: 01-14-2020 2110 Overland Ave, Ste 124Billings, MT WATER LEVEL OBSERVATIONS Groundwater not encountered 1 3 SA M P L E T Y P E 0 10 20 30 40 50 60 0 20 40 60 80 100 CH o r O H CL o r O L ML or OL MH or OH "U" L i n e "A" L i n e ATTERBERG LIMITS RESULTS ASTM D4318 P LAS TIC IT Y I NDE X LIQUID LIMIT PROJECT NUMBER: 26195068 SITE: Westlake Road & East Valley CenterRoad Bozeman, MT PROJECT: Billings Clinic Bozeman Campus CLIENT: Billings Clinic Billings, MT 2110 Overland Ave, Ste 124Billings, MT LA B O R A T O R Y T E S T S A R E N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . A T T E R B E R G L I M I T S 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 NP 30 35 NP 24 22 NP 6 13 PIPLLLBoring ID Depth B-1 B-2 B-3 29.9 94.3 76.5 Fines 10 - 11.5 5 - 7 7.5 - 9 SM ML CL SILTY SAND with GRAVEL SILT LEAN CLAY with SAND DescriptionUSCS CL-ML 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 0.0010.010.1110100 P E R C E N T C O A R S E R B Y W E I G H T GRAIN SIZE DISTRIBUTION ASTM D422 3 2 10 14 506 2001.5 81 140 GRAIN SIZE IN MILLIMETERS 3/4 1/23/8 30 403 60 HYDROMETERU.S. SIEVE OPENING IN INCHES 16 20 100 90 80 70 60 50 40 30 20 10 0 U.S. SIEVE NUMBERS 44 1006 PE R C E N T F I N E R B Y W E I G H T PROJECT NUMBER: 26195068 SITE: Westlake Road & East Valley CenterRoad Bozeman, MT PROJECT: Billings Clinic Bozeman Campus CLIENT: Billings Clinic Billings, MT 2110 Overland Ave, Ste 124Billings, MT LA B O R A T O R Y T E S T S A R E N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . 7 3 1 5 5 0 8 0 G R A I N S I Z E - D 9 5 - D 5 0 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 SILTY SAND with GRAVEL (SM) SILT (ML) LEAN CLAY with SAND (CL)D50 D95 1.455 D60 CC D10 0.077 3.239 3/4" 3/8"#4#8#16#30#50#100 #200 100.0 91.7991.1590.1289.2587.7985.3581.62 76.53 100.0 99.9199.899.5498.6194.32 #8 #16#30#50#100#200 100.0 84.9879.1965.5855.3847.6740.6435.37 32.0129.92 1 1/2" 3/4"3/8"#4#8#16#30#50 #100#200 fine coarse fine SILT OR CLAYCOBBLESGRAVELSAND medium 29.906 0.084 12.454 D30 CU 10 - 11.5 5 - 7 7.5 - 9 SM ML CL 29.9 94.3 76.5 35.7 5.7 14.6 34.4 0.0 8.8 0.0 0.0 0.0 B-1 B-2 B-3 coarse Sieve % Finer Sieve Sieve % Finer SOIL DESCRIPTIONGRAIN SIZE COEFFICIENTS BORING ID % GRAVEL % SAND % SILT% COBBLES % CLAY % Finer DEPTH % FINES USCS REMARKS -12 -10 -8 -6 -4 -2 0 2 100 1,000 10,000 AX I A L S T R A I N , % PRESSURE, psf SWELL CONSOLIDATION TEST ASTM D2435 NOTES: Sample inundated with water at 1,000 psf. PROJECT NUMBER: 26195068 SITE: Westlake Road & East Valley CenterRoad Bozeman, MT PROJECT: Billings Clinic Bozeman Campus CLIENT: Billings Clinic Billings, MT 2110 Overland Ave, Ste 124Billings, MT LA B O R A T O R Y T E S T S A R E N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . T C _ C O N S O L _ S T R A I N - U S C S 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 2 / 4 / 2 0 82 20B-2 SILT(ML)5 - 7 ft Specimen Identification Classification , pcf WC, % 75 80 85 90 95 100 105 110 115 120 125 130 135 0 5 10 15 20 25 30 35 40 45 DR Y D E N S I T Y , p c f WATER CONTENT, % Z A V f o r G s = 2 . 8 Z A V f o r G s = 2 . 7 ZA V f o r G s = 2 . 6 MOISTURE-DENSITY RELATIONSHIP ASTM D698/D1557 PROJECT NUMBER: 26195068 SITE: Westlake Road & East Valley CenterRoad Bozeman, MT PROJECT: Billings Clinic Bozeman Campus CLIENT: Billings Clinic Billings, MT 2110 Overland Ave, Ste 124Billings, MT LA B O R A T O R Y T E S T S A R E N O T V A L I D I F S E P A R A T E D F R O M O R I G I N A L R E P O R T . C O M P A C T I O N - V 2 2 6 1 9 5 0 6 8 B I L L I N G S C L I N I C B . G P J T E R R A C O N _ D A T A T E M P L A T E . G D T 1 / 2 3 / 2 0 ASTM D698 Method B B-4 @ 2.6 - 5 feetSource of Material Description of Material Remarks: Test Method PCF % TEST RESULTS Maximum Dry Density % LL 104.9 Optimum Water Content PIPL ATTERBERG LIMITS 17.5 Percent Fines Lean Clay (CL, visual) PROJECT:Billings Clinic PROJECT NO:26195068 LOCATION:Bozeman, Montana MATERIAL:CL SAMPLE SOURCE:B-4 @ 2.6 - 5.0 ft DATE:2/4/2020 REVIEWED BY:TG COMPACTION(%)94.5%CORRECTED COMPACTION:REMOLDED TO APPX 95% MDD AT OPTIMUM PENETRATION C B R PERCENT SWELL 1.9%0.100 3.1% 0.200 2.9% BEFORE SOAK AFTER SOAK DRY DENSITY 99.1 lbs./cu.ft 97.2 lbs./cu.ft D698 PROCTOR PERCENT MOISTURE 17.5 %27.8 %DRY DENSITY(pcf) 104.9 MOISTURE(%)17.5 SURCHARGE WEIGHT 10 lbs. CBR (CALIFORNIA BEARING RATIO) OF LABORATORY-COMPACTED SOILS (ASTM D1883) 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 0 0.1 0.2 0.3 0.4 0.5 P E N E T R A T I O N S T R E S S (p s i ) PENETRATION (in) 2110 Overland Avenue, Suite 124, Billings, Montana PHONE: (406) 656-3072 FAX: (406) 656-3578 ISSUED: 2/4/2020 SUPPORTING INFORMATION Contents: General Notes Unified Soil Classification System Note: All attachments are one page unless noted above. February 4, 2020 Terracon Project No. 26195068 Billings Clinic Bozeman Campus Bozeman, MT 500 to 1,000 > 8,000 4,000 to 8,000 2,000 to 4,000 1,000 to 2,000 less than 500 Unconfined Compressive StrengthQu, (psf) GrabSample ShelbyTube Split Spoon N (HP) (T) (DCP) UC (PID) (OVA) Standard Penetration TestResistance (Blows/Ft.) Hand Penetrometer Torvane Dynamic Cone Penetrometer Unconfined CompressiveStrength Photo-Ionization Detector Organic Vapor Analyzer SAMPLING WATER LEVEL FIELD TESTS Soil classification as noted on the soil boring logs is based Unified Soil Classification System. Where sufficient laboratory data exist to classify the soils consistent with ASTM D2487 "Classification of Soils for Engineering Purposes" this procedure is used. ASTM D2488 "Description and Identification of Soils (Visual-Manual Procedure)" is also used toclassify the soils, particularly where insufficient laboratory data exist to classify the soils in accordance with ASTM D2487.In addition to USCS classification, coarse grained soils are classified on the basis of their in-place relative density, and fine-grained soils are classified on the basis of their consistency. See "Strength Terms" table below for details. The ASTM standards noted above are for reference to methodology in general. In some cases, variations to methods are applied as aresult of local practice or professional judgment. DESCRIPTIVE SOIL CLASSIFICATION Exploration point locations as shown on the Exploration Plan and as noted on the soil boring logs in the form of Latitude and Longitude are approximate. See Exploration and Testing Procedures in the report for the methods used to locate the exploration points for this project. Surface elevation data annotated with +/- indicates that no actual topographical surveywas conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic maps of the area. LOCATION AND ELEVATION NOTES The soil boring logs contained within this document are intended for application to the project as described in this document. Use of these soil boring logs for any other purpose may not be appropriate. GENERAL NOTES DESCRIPTION OF SYMBOLS AND ABBREVIATIONS RELEVANCE OF SOIL BORING LOG Water levels indicated on the soil boring logs are the levels measured in the borehole at the timesindicated. Groundwater level variations will occur over time. In low permeability soils, accuratedetermination of groundwater levels is not possible with short term water levelobservations. Water Initially Encountered Water Level After a Specified Period of Time Water Level Aftera Specified Period of Time Cave InEncountered STRENGTH TERMS Standard Penetration orN-ValueBlows/Ft. Descriptive Term(Density) Hard 15 - 30Very Stiff> 50Very Dense 8 - 15Stiff30 - 50Dense 4 - 8Medium Stiff10 - 29Medium Dense 2 - 4Soft4 - 9Loose 0 - 1Very Soft0 - 3Very Loose (50% or more passing the No. 200 sieve.)Consistency determined by laboratory shear strength testing, field visual-manualprocedures or standard penetration resistance > 30 Descriptive Term(Consistency)Standard Penetration orN-ValueBlows/Ft. (More than 50% retained on No. 200 sieve.)Density determined by Standard Penetration Resistance CONSISTENCY OF FINE-GRAINED SOILSRELATIVE DENSITY OF COARSE-GRAINED SOILS UNIFIED SOIL CLASSIFICATION SYSTEM UNIFIED SOIL CLASSIFICATION SYSTEM 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% ofcoarse fraction retained on No. 4 sieve Clean Gravels: Less than 5% finesC Cu ³ 4 and 1 £ Cc £ 3 E GW Well-graded gravel F Cu < 4 and/or [Cc<1 or Cc>3.0]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 gravelF, G, H Sands: 50% or more of coarse fraction passes No. 4 sieve Clean Sands: Less than 5% finesD Cu ³ 6 and 1 £ Cc £ 3E SW Well-graded sandI Cu < 6 and/or [Cc<1 or Cc>3.0]E SP Poorly graded sandI Sands with Fines: More than 12% fines D Fines classify as ML or MH SM Silty sandG, 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” lineJ CL Lean clayK, L, M PI < 4 or plots below “A” line J ML Silt K, L, M Organic:Liquid limit - oven dried < 0.75 OL Organic clayK, 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 clayK, L, M PI plots below “A” line MH Elastic SiltK, L, M Organic:Liquid limit - oven dried < 0.75 OH Organic clayK, 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. 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 = 6010 2 30 DxD )(D F If soil contains ³ 15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. HIf fines are organic, add “with organic fines” to group name. I If soil contains ³ 15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. KIf soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains ³ 30% plus No. 200 predominantly sand, add “sandy” to group name. MIf soil contains ³ 30% plus No. 200, predominantly gravel, add “gravelly” to group name. NPI ³ 4 and plots on or above “A” line. OPI < 4 or plots below “A” line. P PI plots on or above “A” line. QPI plots below “A” line.