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Home My WebLink AboutPOLESTAR VILLAGE - FDP240010 - SUBMITTAL DOCUMENTS - ROUND 1 - Geotechnical (Soils) Report (2) CTL|Thompson, Inc. Denver, Fort Collins, Colorado Springs, Glenwood Springs, Pueblo, Summit County – Colorado Cheyenne, Wyoming and Bozeman, Montana December 30, 2022 Polestar Gardens, Inc. 850 South Overland Trail #15 Fort Collins, Colorado 80521 Attn: Michael Gornik Subject: Supplementary Preliminary Investigation Addendum Polestar Village Fort Collins, Colorado CTL|T Project Number: FC10101.001-115 L1 CTL|Thompson, Inc. previously provided a Preliminary Geotechnical Investigation for the proposed Polestar Village in Fort Collins, Colorado for CTL|T Project No. FC10101-115, report dated November 18, 2021. Following that investigation, we performed monthly groundwater monitoring for one calendar year during September 2021 to September 2022 . The original study discovered subsurface conditions that warranted additional exploration. To address this, additional borings and test pits were requested to further explore the subsurface conditions. Exploration pits were excavated on October 11, 2022, and additional borings were drilled on November 22, and 23, 2022. Proposed Construction Preliminary Development and Utility Plans prepared by J.R. Engineering, Job No. 39797.01, dated June 15, and 24, 2022 were provided for review. The Polestar Village development as proposed, includes mixed-use single-family and multi-family residential housing, retail/commercial buildings, and agricultural space. Paved interior roads, alleyways, and parking are also planned within the development. The development will be served by buried utilities. Exploratory Pits Six exploratory test pits were excavated at the locations presented in Figure 1. The pits were excavated to gain more information about possible undocumented fill. The pits were excavated to depths of 3½ to 5½ feet. The strata encountered in the pits was variable across the site (see pictures below). In general, the strata included approximately 1 to 1 ½ feet of sandy clay or clayey sand topso il over alluvial deposits of silty, clayey sand and gravel with occasio nal cobble overlying weathered claystone bedrock. Clasts and concretions of shale, limestone, and other sedimentary rock were present in some of the pits. An unmarked and unidentified 2-inch steel utility line was encountered at approximately 3 feet during the excavation for Pit 1. That line was surrounded by fill comprised of sand, gravel, and clay. That excavation was backfilled, and Pit 1 was moved a few feet to the south. Groundwater was not encountered in the ex cavations. All of the pits were backfilled after observations. POLESTAR GARDENS, INC POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 2 Pictures 1, 2, and 3: Exploratory Pits Based on the observations of the exploratory pits, we believe that what was thought to be fill in the borings from the initial investigation, was likely alluvium comprised of well graded silty, clayey sand, gravel and limestone pediments. The alluvium is well consolidated and likely poses low risk of settlement to improvements built above it. Undocumented fill may exist in areas not explored by our exploratory borings and pits. If fill is encountered during the construction of structures, CTL|Thompson should be consulted to determine the nature of the fill and the recommendations provided in the original repo rt should be followed if warranted. Supplemental Exploratory Borings In general, strata encountered in the additional borings included 2 to 12 feet of sandy clay or silty, clayey sand overlying weathered to competent claystone be drock to the depths explored. Clean to slightly clayey, silty sand and gravel was encountered below the topsoil to about 6 feet in boring TH-7. Bedrock elevation and depth is presented in Figure 4. Standard penetration test results indicated that the granular materials were medium dense, the clayey materials stiff to very stiff and the bedrock firm to hard. Samples of the clayey soil exhibited swell potential of 0.3 to 6.7 percent when wetted under approximate overburden pressure. The claystone bedrock exhibited swell of 1.5 to 11.8 percent. Further description of the subsurface conditions is presented in our boring logs (Figure 5) and laboratory test results Appendix A. The laboratory testing results, field information collected from test pits and borings, along with our experience, were used to predict potential soil heave of the surficial soils. Heave estimates varied across the site from less than 1/2-inch up to 9 inches with most of the site predicted to heave between 4 and 9 inches. The expansive potential is primarily associated with the bedrock materials. While the surficial soils appear to generally exhibit a lower degree of expansion, there may still be higher swelling soils in areas not yet explored. Groundwater was measured in seven borings at depths of 2 to 18½ feet (approximate elevations 5090 to 5113). Groundwater depths and elevations are presented in Figure 2 and the measurements of the original piezometers from the yearlong groundwater study are presented in Figure 3. Groundwater fluctuates seasonally and may be influenced by the Pleasant Valley Lake Canal and the nearby retention pond. There may be other unknown sources contributing to the groundwater on this site. POLESTAR GARDENS, INC POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 3 Supplemental Discussion Geologic hazards exist on this site that will present challenges for development. The preliminary development recommendations presented in our original report remain valid. Site grading should be adjusted where possible to avoid shallow groundwater. Groundwater depths will also limit possible foundation depths unless groundwater control measures are implemented. Foundations placed on drilled piers remain the lowest risk option to reduce the likelihood of differential movement in structures. Shallow founded structures such as crawlspace foundations, post tensioned slabs, or monolithic slabs could also be considered if some degree of movement is permitted. The shallow foundations will likely need to be placed on an over-excavated mat of soil to reduce the risk of movements. The depth of over-excavation will need to be determined during design level investigations once final grade elevations have been decided. For planning purposes, estimations of over- excavation depths are on the order of 7 feet from current grade or 4 feet below shallow foundations. We understand that the client would like to consider basements where feasible. It is difficult to delineate areas where basements will be feasible because of the highly variable nature of the subsurface strata. Portions of the site are overlain by up to several feet of well mixed alluvial soils. The bedrock is relatively shallow and mostly impermeable which can create areas of perched water. There are gypsiferous seams and natural fractures in the bedrock that present pathways for water movement and migration. With development, especially of deeper utilities, new path ways for water are created, which can create new conditions. Basements should only be considered on lots or in areas where a permanent separation of at least 3 feet between foundation elements and slabs, and groundwater can be maintained. Based on groundwater conditions encountered during this investigation and the previous investigations, basement level construction is not recommended for most of the site. Areas where basement construction may likely be considered include the condominiums, duplexes, and townhomes proposed north and east of West Plum Street. Basements are not recommended for the single -family detached lots on Blocks 1 through 4 or the proposed structures south and west of West Plum Street, unless the grade can be raised to meet the recommended separation or other groundwater control systems are implemented. With development, ch anges to the site groundwater table may lead to changes in recommendations. Design level investigations will be critical to address and mitigate the challenging conditions this site presents. The construction alternatives discussed in this letter are given with the assumption that all other recommendations in our preliminary report are followed. We appreciate the opportunity to work with you on this project. Please do not hesitate to co ntact us with any other questions or concerns. Sincerely, CTL|THOMPSON, INC. Trace Krausse, EI R.B. “Chip” Leadbetter III, PE Geotechnical Project Engineer Senior Geotechnical Engineer TH-10 TH-9 TH-8 TH-7 TH-6 TH-5 TH-3 West Orchard Place West Plum Street TH-4 Ki m b a l l R o a d TH-1 TH-2 P-1 P-6 P-5 P-4 P-3P-2 PIT-1 PIT-4 PIT-5 PIT-2 PIT-6 PIT-3 OV E R L A N D T R A I L TA F T H I L L R D . W. MULBERRY ST. W. ELIZABETH ST. SITE LEGEND: PIT-1 TH-3 INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING THIS INVESTIGATION TH-1 INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING IN PREVIOUS INVESTIGATION INDICATES APPROXIMATE LOCATION OF TEMPORARY PIEZOMETER P-1 INDICATES APPROXIMATE LOCATION OF EXPLORATORY TEST PIT FIGURE 1 Locations of Exploratory Borings and Pits POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL I T PROJECT NO. FC10101.001-115 L1 0 150'75' APPROXIMATE SCALE: 1"=150' VICINITY MAP FORT COLLINS, COLORADO NOT TO SCALE POLESTAR GARDENS, INC. TH-6 TH-5 TH-3 West Orchard Place TH-4 Ki m b a l l R o a d TH-1 TH-2 P-1 P-3P-2 TH-10 TH-9 TH-8 TH-7 West Plum Street P-6 P-5 P-4 (8.5) (4.5) (18.5) (>24) (18.5) (15)(9) (16.5) (21) (6.5) (3.5) (8) (8)(1) (2.5) (18) [5107.8] [5096.8][5097.0] [5115.2] [5102.9] [5114.5] [5089.7] [5106.7] [5094.9] [5091.5] [5092.2] [5110.4] [5113.3] [5096.7] [5103.1] LEGEND: (4.5)INDICATES MOST SHALLOW APPROXIMATE DEPTH IN FEET TO GROUNDWATER MEASURED DURING INVESTIGATIONS [5110.4]INDICATES APPROXIMATE GROUNDWATER ELEVATION (FEET) INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING IN PREVIOUS INVESTIGATION INDICATES APPROXIMATE LOCATION OF TEMPORARY PIEZOMETER TH-3 TH-1 P-1 FIGURE 2 Groundwater Depth and Elevation POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL I T PROJECT NO. FC10101.001-115 L1 0 150'75' APPROXIMATE SCALE: 1"=150' POLESTAR GARDENS, INC. 9/24/2021 10/18/2021 11/18/2021 12/15/2021 1/12/2022 2/15/2022 3/16/2022 4/12/2022 5/18/2022 6/14/2022 7/11/2022 8/17/2022 9/14/2022 P-1 5116.3 5107.8 5107.8 5107.8 5107.3 5106.3 5106.8 5106.3 5106.8 5106.8 5106.8 5106.8 5107.8 5107.3 P-2 5111.8 5089.8 5092.8 5095.3 5095.8 5095.8 5096.3 5096.8 5096.3 5096.3 5095.3 5095.8 5095.8 5095.8 P-3 5106.0 5096.0 5097.0 5096.5 5096.5 5095.0 5095.5 5095.0 5095.5 5095.0 5093.5 5095.5 5096.0 5095.0 P-4 5110.9 5088.4 5091.9 5096.9 5099.9 5100.9 5102.4 5102.4 5102.9 5102.9 5102.4 5102.9 5102.9 5102.4 P-5 5115.5 5095.0 5104.0 5109.0 5109.5 5109.0 5109.0 5114.5 5109.3 5109.0 5109.0 5109.5 5109.5 5109.5 P-6 5118.7 5115.2 5114.7 5112.7 5112.2 5111.2 5111.2 5112.2 5112.3 5113.7 5113.7 5114.2 5114.2 5113.2 Piezometer #Groundwater Elevation (feet)Piezometer Elevation (feet) Piezometer # 9/24/2021 10/18/2021 11/18/2021 12/15/2021 1/12/2022 2/15/2022 3/16/2022 4/12/2022 5/18/2022 6/14/2022 7/11/2022 8/17/2022 9/14/2022 P-1 8.5 8.5 8.5 9 10 9.5 10 9.5 9.5 9.5 9.5 8.5 9 P-2 22 19 16.5 16 16 15.5 15 15.5 15.5 16.5 16 16 16 P-3 10 9 9.5 9.5 11 10.5 11 10.5 11 12.5 10.5 10 11 P-4 22.5 19 14 11 10 8.5 8.5 8 8 8.5 8 8 8.5 P-5 20.5 11.5 6.5 6 6.5 6.5 1 6.2 6.5 6.5 6 6 6 P-6 3.5 4 6 6.5 7.5 7.5 6.5 6.4 5 5 4.5 4.5 5.5 Ditch Running?Yes Covered in Snow No Yes Yes Yes Yes Yes Yes Yes Groundwater Depth (feet) FIGURE 3 Groundwater Measurements Groundwater Measurements September 2021 to September 2022 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL I T PROJECT NO. FC10101.001-115 L1 TH-6 TH-5 TH-3 West Orchard Place TH-4 Ki m b a l l R o a d TH-1 TH-2 P-1 P-3P-2 TH-10 TH-9 TH-8 TH-7 West Plum Street P-6 P-5 P-4 (7) (8) (7) (12) (4) (7)(5) (3) (9) (11) (11) (5) (8)(7) (3) (3) [5109.3] [5104.8][5101.0] [5107.6] [5105.8] [5108.5] [5102.2] [5103.2] [5109.4] [5103.5] [5105.7] [5105.9] [5108.1] [5111.7] [5103.1] [5105.7] LEGEND: INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING INDICATES APPROXIMATE LOCATION OF EXPLORATORY BORING IN PREVIOUS INVESTIGATION INDICATES APPROXIMATE LOCATION OF TEMPORARY PIEZOMETER TH-3 TH-1 P-1 (7)INDICATES APPROXIMATE DEPTH TO BEDROCK (FEET) [(5110.4]INDICATES APPROXIMATE BEDROCK ELEVATION (FEET) FIGURE 4 Bedrock Depth and Elevation POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL I T PROJECT NO. FC10101.001-115 L1 0 150'75' APPROXIMATE SCALE: 1"=150' POLESTAR GARDENS, INC. 5,080 5,085 5,090 5,095 5,100 5,105 5,110 5,115 5,120 5,075 5,080 5,085 5,090 5,095 5,100 5,105 5,110 5,115 5,120 12/12 26/12 46/12 50/10 50/12 DD=107SW=1.0pF=3.53 WC=7.0DD=119pF=3.53-200=20 WC=15.9DD=120SW=4.5pF=4.06 WC=15.5DD=117SW=4.1pF=4.13 WC=16.6DD=116SW=1.9pF=3.95 WC=17.9 TH-3 El. 5117.7 13/12 35/12 50/12 49/12 50/9 WC=13.9 DD=114SW=0.3 WC=16.9DD=115SW=4.3 TH-4 El. 5108.2 45/12 50/11 50/12 50/8 50/7 WC=9.9DD=131SW=7.3SS=0.640 WC=13.5DD=123SW=2.2 TH-5 El. 5113.4 33/12 36/12 50/11 43/12 50/9 WC=12.3DD=124SW=11.8SS=0.040 WC=14.3DD=123SW=5.0 TH-6 El. 5108.7 20/12 17/12 37/12 50/11 WC=17.5-200=39 TH-7 El. 5116.9 17/12 47/12 50/9 50/8 50/9 WC=13.2DD=125 SW=4.1 WC=12.6DD=127SW=2.8 TH-8 El. 5115.9 26/12 49/12 50/9 50/6 50/7 SS=0.060 WC=14.1DD=121SW=6.3 WC=12.7DD=121SW=2.7 WC=12.1DD=126SW=3.2 WC=12.6DD=126SW=1.5 TH-9 El. 5114.7 24/12 38/12 50/12 50/9 20/12 WC=13.5DD=120SW=6.7 WC=13.1DD=122SW=5.5 TH-10 El. 5111.1 DRIVE SAMPLE. THE SYMBOL 12/12 INDICATES 12 BLOWS OF A 140-POUND HAMMER FALLING 30 INCHES WERE REQUIRED TO DRIVE A 2.5-INCH O.D. SAMPLER 12 INCHES. EL E V A T I O N - F E E T FIGURE 5 EL E V A T I O N - F E E T WATER LEVEL MEASURED NOVEMBER 28, 2022. SAND, CLAYEY, SILTY WITH OCCASIONAL GRAVEL, SLIGHTLY MOIST, MEDIUM DENSE TO DENSE, BROWN, GRAY (SC) 2. 3. CLAY, SANDY, WITH OCCASIONAL GRAVEL, SLIGHTLY MOIST TO MOIST, STIFF, BROWN, GRAY, RUST (CL) 1. LEGEND: NOTES: SAND, GRAVELLY, CLEAN TO SLIGHTLY CLAYEY/SILTY, MOIST, MEDIUM DENSE, BROWN, RUST, TAN (SP, SP-SC) WEATHERED CLAYSTONE, SLIGHTLY SANDY, SLIGHTLY MOIST, MEDIUM HARD, BROWN, GRAY, RUST CLAYSTONE, SANDY, SLIGHTLY MOIST, FIRM TO HARD, BROWN, GRAY, RUST WATER LEVEL MEASURED AT TIME OF DRILLING. BORING ELEVATIONS WERE SURVEYED BY A REPRESENTATIVE OF THE CLIENT. THESE LOGS ARE SUBJECT TO THE EXPLANATIONS, LIMITATIONS AND CONCLUSIONS IN THIS REPORT. 4. Summary Logs of Exploratory Borings WC DD SW -200 SS - - - - - INDICATES MOISTURE CONTENT (%). INDICATES DRY DENSITY (PCF). INDICATES SWELL WHEN WETTED UNDER OVERBURDEN PRESSURE (%). INDICATES PASSING NO. 200 SIEVE (%). INDICATES SOLUBLE SULFATE CONTENT (%). DRIVE SAMPLE. THE SYMBOL INDICATES BLOWS OF A 140-POUND HAMMER FALLING 30 INCHES WERE REQUIRED TO DRIVE A 2.0-INCH O.D. SAMPLER INCHES. THE BORINGS WERE DRILLED ON NOVEMBER 22 AND 23, 2022 USING 4-INCH DIAMETER CONTINUOUS-FLIGHT AUGERS AND A TRUCK-MOUNTED DRILL RIG. 5,075 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 APPENDIX A RESULTS OF LABORATORY TESTS Sample of CLAY, SANDY (CL) DRY UNIT WEIGHT=107 PCF From TH - 3 AT 4 FEET MOISTURE CONTENT=17.9 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A -1 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, WEATHERED DRY UNIT WEIGHT=120 PCF From TH - 3 AT 14 FEET MOISTURE CONTENT=15.9 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A-2 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=117 PCF From TH - 3 AT 19 FEET MOISTURE CONTENT=15.5 % DRY UNIT WEIGHT=116 PCF MOISTURE CONTENT=16.6 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 3 CO M P R E S S I O N % E X P A N S I O N -3 -2 -1 0 1 2 3 4 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING -4 -3 -2 -1 0 1 2 3 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 0.1 1.0 10 100 Sample oAfPPL C I L E A D YS P T R O E N S E S , U S R A E N - DY KSF From TH - 3 AT 24 FEET POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAY, SANDY (CL) DRY UNIT WEIGHT=114 PCF From TH - 4 AT 4 FEET MOISTURE CONTENT=13.9 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 4 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=115 PCF From TH - 4 AT 14 FEET MOISTURE CONTENT=16.9 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A-5 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=131 PCF From TH - 5 AT 9 FEET MOISTURE CONTENT=9.9 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A -6 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=123 PCF From TH - 5 AT 19 FEET MOISTURE CONTENT=13.5 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 7 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, WEATHERED DRY UNIT WEIGHT=124 PCF From TH - 6 AT 4 FEET MOISTURE CONTENT=12.3 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 8 -2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=123 PCF From TH - 6 AT 14 FEET MOISTURE CONTENT=14.3 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A-9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, WEATHERED DRY UNIT WEIGHT=125 PCF From TH - 8 AT 9 FEET MOISTURE CONTENT=13.2 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A -10 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=127 PCF From TH - 8 AT 19 FEET MOISTURE CONTENT=12.6 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 Swell Consolidation Test Results FIGURE A-11 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, WEATHERED DRY UNIT WEIGHT=121 PCF From TH - 9 AT 9 FEET MOISTURE CONTENT=14.1 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 12 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=121 PCF From TH - 9 AT 14 FEET MOISTURE CONTENT=12.7 % Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=126 PCF From TH - 9 AT 19 FEET MOISTURE CONTENT=12.1 % APPLIED PRESSURE -KSF APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N CO M P R E S S I O N % E X P A N S I O N -4 -3 -2 -1 0 1 2 3 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING -4 -3 -2 -1 0 1 2 3 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Swell Consolidation Test Results FIGURE A-13 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=126 PCF From TH - 9 AT 24 FEET MOISTURE CONTENT=12.6 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 14 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAY, SANDY (CL) DRY UNIT WEIGHT=120 PCF From TH - 10 AT 4 FEET MOISTURE CONTENT=13.5 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 15 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of CLAYSTONE, SANDY DRY UNIT WEIGHT=122 PCF From TH - 10 AT 9 FEET MOISTURE CONTENT=13.1 % APPLIED PRESSURE -KSF CO M P R E S S I O N % E X P A N S I O N Swell Consolidation Test Results FIGURE A - 16 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTING 0.1 1.0 10 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 Sample of SAND, GRAVELLY, CLAYEY (SC)GRAVEL 22 %SAND 58 % From TH - 3 AT 9 FEET SILT & CLAY 20 %LIQUID LIMIT % PLASTICITY INDEX % Sample of SAND, CLAYEY, GRAVELLY (SC)GRAVEL 19 %SAND 42 % From TH - 7 AT 9 FEET SILT & CLAY 39 %LIQUID LIMIT % PLASTICITY INDEX % FIGURE A-17 Gradation Test Results 0.002 15 MIN. .005 60 MIN. .009 19 MIN. .019 4 MIN. .037 1 MIN. .074 *200 .149 *100 .297 *50 0.42 *40 .590 *30 1.19 *16 2.0 *10 2.38 *8 4.76 *4 9.52 3/8" 19.1 3/4" 36.1 1½" 76.2 3" 127 5" 152 6" 200 8" .001 45 MIN. 0 10 20 30 40 50 60 70 80 90 100 CLAY (PLASTIC) TO SILT (NON-PLASTIC) SANDS FINE MEDIUM COARSE GRAVEL FINE COARSE COBBLES DIAMETER OF PARTICLE IN MILLIMETERS 25 HR.7 HR. HYDROMETER ANALYSIS SIEVE ANALYSIS TIME READINGS U.S. STANDARD SERIES CLEAR SQUARE OPENINGS PE R C E N T P A S S I N G 0 10 20 30 50 60 70 80 90 100 PE R C E N T R E T A I N ED 40 0.002 15 MIN. .005 60 MIN. .009 19 MIN. .019 4 MIN. .037 1 MIN. .074 *200 .149 *100 .297 *50 0.42 *40 .590 *30 1.19 *16 2.0 *10 2.38 *8 4.76 *4 9.52 3/8" 19.1 3/4" 36.1 1½" 76.2 3" 127 5" 152 6" 200 8" .001 45 MIN. 0 10 20 30 40 50 60 70 80 90 100 CLAY (PLASTIC) TO SILT (NON-PLASTIC)SANDS FINE MEDIUM COARSE GRAVEL FINE COARSE COBBLES DIAMETER OF PARTICLE IN MILLIMETERS 25 HR.7 HR. HYDROMETER ANALYSIS SIEVE ANALYSIS TIME READINGS U.S. STANDARD SERIES CLEAR SQUARE OPENINGS PE R C E N T P A S S I N G PE R C E N T R E T A I N E D 0 10 20 30 40 50 60 70 80 90 100 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL | T PROJECT NO. FC10101.001-115 L1 PASSING WATER- MOISTURE DRY APPLIED NO. 200 SOLUBLE DEPTH CONTENT DENSITY SWELL*PRESSURE SUCTION SIEVE SULFATES BORING (FEET)(%)(PCF)(%)(PSF)(PF)(%)(%)DESCRIPTION TH-3 4 17.9 107 1.0 500 3.53 CLAY, SANDY (CL) TH-3 9 7.0 119 3.53 20 SAND, CLAYEY (SC) TH-3 14 15.9 120 4.5 1,800 4.06 CLAYSTONE, WEATHERED TH-3 19 15.5 117 4.1 2,400 4.13 CLAYSTONE, SANDY TH-3 24 16.6 116 1.9 3,000 3.95 CLAYSTONE, SANDY TH-4 4 13.9 114 0.3 500 CLAY, SANDY (CL) TH-4 14 16.9 115 4.3 1,800 CLAYSTONE, SANDY TH-5 9 9.9 131 7.3 1,100 0.64 CLAYSTONE, SANDY TH-5 19 13.5 123 2.2 2,400 CLAYSTONE, SANDY TH-6 4 12.3 124 11.8 500 0.04 CLAYSTONE, WEATHERED TH-6 14 14.3 123 5.0 1,800 CLAYSTONE, SANDY TH-7 9 17.5 39 SAND, CLAYEY (SC) TH-8 9 13.2 125 4.1 1,100 CLAYSTONE, WEATHERED TH-8 19 12.6 127 2.8 2,400 CLAYSTONE, SANDY TH-9 4 0.06 CLAY, SANDY (CL) TH-9 9 14.1 121 6.3 1,100 CLAYSTONE, WEATHERED TH-9 14 12.7 121 2.7 1,800 CLAYSTONE, SANDY TH-9 19 12.1 126 3.2 2,400 CLAYSTONE, SANDY TH-9 24 12.6 126 1.5 3,000 CLAYSTONE, SANDY TH-10 4 13.5 120 6.7 500 CLAY, SANDY (CL) TH-10 9 13.1 122 5.5 1,100 CLAYSTONE, SANDY SWELL TEST RESULTS* TABLE A-I SUMMARY OF LABORATORY TESTING Page 1 of 1 POLESTAR GARDENS, INC. POLESTAR VILLAGE SUPPLEMENTAL INVESTIGATION CTL|T PROJECT NO. FC10101.001-115 L1