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Home My WebLink AboutWILLOX FARM - PDP220008 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORT 4396 GREENFIELD DRIVE W INDSOR, COLORADO 80550 (970) 545-3908 FAX (970) 663-0282 www.earth-engineering.com April 13,2022 Arbor Capital Group 4040 Mac Arthur Blvd. Newport Beach, CA 92660 Attn: Mr. Andrew Hartsel (a.hartsel@developmentbymosaic.com) Re: Supplemental Subsurface Exploration / Geotechnical Engineering Report Proposed Willox Farm Residential Development (Larimer County Parcel #970220003) Approximately 19.3-Acres – South of Willox Lane and ½-Mile West of College Avenue Installation of 1 Groundwater Monitoring Well and 4 Piezometers Fort Collins, Colorado EEC Project No. 1212027 Mr. Hartsel: Earth Engineering Consultants, LLC (EEC) personnel have completed the supplemental subsurface exploration and the installation of the requested one (1) long-term groundwater monitoring well (MW) and the four (4) temporary piezometers (PZs) for the referenced project. The purpose of our supplemental assessment was to provide a mechanism to measure and evaluate the groundwater fluctuations and characteristics across the property to assist Miller Groundwater Engineering, LLC in the evaluation of a possible area underdrain system. This supplemental study was completed in general accordance with our proposal dated March 14, 2022. EEC personnel had previously completed a preliminary subsurface exploration for the Willox Farms property in 2021. The preliminary subsurface exploration conducted by EEC in April 2021, in which seven (7) preliminary borings were completed at random locations across the site, had recorded groundwater levels at approximate depths of 3 to 5 feet below existing site grades. For further information and findings thereof, please refer to our Preliminary Subsurface Exploration Report dated May 6, 2021, EEC Project No. 1212027. For this phase of the project we understand the installation of the requested single MW and four (4) PZs (registered with the State of Colorado – Division of Water Resources), will assist the design team in evaluating the necessity and possible design of an area underdrain system for the property in an effort to develop the site for possible below grade residential basement construction. Earth Engineering Consultants, LLC EEC Project No. 1212027 Supplemental Subsurface Exploration Report – Willox Farms Fort Collins, Colorado April 13, 2022 Page 2 SITE EXPLORATION AND TESTING PROCEDURES As part of this study, EEC personnel completed one (1) MW and four (4) PZs at the approximate locations as indicated on the site diagram included with this report. The borings were extended to depths of approximately 15 feet below existing site grades. Upon completion of the drilling operations, the borehole labeled herein as MW-1 was converted to an approximate 15 foot PVC cased monitoring well, while the boreholes labeled herein as PZ-1 through PZ-4 were converted to temporary, approximate 15 feet, hand/field slotted piezometers, for use to develop groundwater characteristics. Results of the field and laboratory testing completed for this assessment are included with this report. The MW and the four (4) PZ exploratory boring locations were established in the field prior to drilling by EEC personnel, with the assistance from Calvin Miller, P.E., PhD, with Miller Groundwater Engineering, LLC, by use of a hand-held GPS unit and by pacing from identifiable site features at locations accessible to our drilling equipment. The boring locations are presented on the attached boring location diagram. The soil borings were completed using a truck-mounted, CME 55 drill rig equipped with a hydraulic head employed in drilling and sampling operations. The boreholes were advanced using 4¼-inch nominal inside diameter (ID) hollow stem augers to maintain open boreholes for sampling and PVC piezometer/pipe installation. Samples of the subsurface materials encountered were obtained using the split barrel/Standard Penetration Test (SPT) sampling procedures in general accordance with ASTM Specifications D1586. In the split-barrel sampling procedure, standard sampling spoons are driven into the ground by means of a 140-pound hammer falling a distance of 30 inches. The number of blows required to advance the split barrel sampler is recorded and is used to estimate the in-situ relative density of cohesionless soils and, to a lesser degree of accuracy, the consistency of cohesive soils. All samples obtained in the field were sealed and returned to our laboratory for further examination, classification and testing. After completing the drilling and sampling, and prior to removal of the hollow stem augers, PVC casings were installed in the open boreholes through the hollow stem augers. The MW was constructed with 2-inch nominal diameter schedule 40 manufactured well screen and riser pipe. Earth Engineering Consultants, LLC EEC Project No. 1212027 Supplemental Subsurface Exploration Report – Willox Farms Fort Collins, Colorado April 13, 2022 Page 3 In general, the MW consisted of an approximate 10-foot section of flush threaded slotted well screen to depths as indicated on the enclosed boring log, with flush threaded solid riser pipe, as required, to extend the MW to the above ground surface elevations. The screened portion of the MW was backfilled with 10/20 silica sand, with an approximate 2-foot bentonite plug/seal placed above the sand layer, and then backfilled with a blend of the auger cuttings generated and bentonite to the existing ground surface elevations. For the piezometers (PZs) a hand/field slotted 1-inch diameter PVC casing was installed in each borehole. Cross-sectional schematics of the MW/PZ installations are indicated on the attached boring logs. The State of Colorado Division of Water Resources was notified of intent to construct monitoring holes prior to beginning the field exploration. Copies of those notices with acknowledgement from the State Engineer’s Office are available upon request. The well construction and test reports will be provided to the Division of Water Resources including copies of the boring logs provided with this report. If the monitoring wells (MW) will remain in place longer than 18 months, it will be necessary to notify the Division of Water Resources and complete registration of those wells. Installation was completed by a licensed water well driller, (Drilling Engineers of Fort Collins), and was completed in accordance with the water well construction rules from the Division of Water Resources. Laboratory testing completed on recovered samples included moisture content and visual classification of the samples. Atterberg limits tests were completed on selected samples to evaluate the soil’s plasticity. Washed sieve analyses were also completed on selected samples to evaluate the grain size distribution of the subsurface materials encountered. The grain size distribution samples were recovered in a standard split-barrel sampler so that any larger size materials in the subsoils would be excluded from the test samples. Results of the outlined tests are indicated on the attached boring logs and summary sheets. As part of the testing program, all samples were examined in the laboratory by an engineer and classified in accordance with the attached General Notes and the Unified Soil Classification System, based on the soil’s texture and plasticity. The estimated group symbol for the Unified Soil Classification System is indicated on the boring logs and a brief description of that classification system is included with this report. Earth Engineering Consultants, LLC EEC Project No. 1212027 Supplemental Subsurface Exploration Report – Willox Farms Fort Collins, Colorado April 13, 2022 Page 4 SITE AND SUBSURFACE CONDITIONS The Willox Farm Residential Development parcel is located south of Willox Lane and approximately 1/2-mile west of North College Avenue in Fort Collins, Colorado. The project site is generally undeveloped and situated west of the Hickory Village residential development. Open space is located to the southwest and south of the site with existing farm ground to the northeast. The site is relatively flat with an estimated relief of approximately 5-feet (+/-) from north to south. An EEC field engineer was on-site during drilling to direct the drilling activities and evaluate the subsurface materials encountered. Field descriptions of the materials encountered were based on visual and tactual observation of disturbed samples and auger cuttings. The boring/piezometer and groundwater monitoring logs included with this report may contain modifications to the field logs based on results of laboratory testing and engineering evaluation. Based on results of the field and laboratory evaluation, subsurface conditions can be generalized as follows. In summary, the subsurface soils encountered in the supplemental piezometer borings generally consisted of a relative shallow depth of overburden slightly cohesive subsoils underlain by a zone of fine to coarse granular subsoils, which extended to the depths explored, approximately 14 to 15 feet below existing site grades. Clayey sand, silty, clayey sand and/or sandy lean clay subsoils were encountered in each of the PVC cased borings beneath the surficial topsoil/vegetative layer and extended to depths of approximately 3 to 5 feet below existing site grades. Silty sand with gravel with interbedded cobbles at increased depths, was encountered beneath the upper slightly cohesive zone and extended to the depths explored, approximately 14 to 15 feet below existing site grades. Auguer refusal was encountered in MW-1 within a very dense granular/cobble zone at a depth of approximately 14 feet below existing site grades. The upper slightly cohesive subsoils were generally dry to moist in-situ, soft to stiff / loose to medium dense in consistency and exhibited low to moderate plasticity. The granular zone was moist to wet, and medium dense to dense in relative density. The stratification boundaries indicated on the boring logs represent the approximate locations of changes in soil and rock types; in-situ, the transition of materials may be gradual and indistinct. Earth Engineering Consultants, LLC EEC Project No. 1212027 Supplemental Subsurface Exploration Report – Willox Farms Fort Collins, Colorado April 13, 2022 Page 5 GROUNDWATER OBSERVATIONS Observations were made while drilling and after the completion of drilling to detect the presence and level of free water. Subsequent groundwater measurements were also performed on April 7, 2022. Groundwater and/or the presence of a piezometric water surface, was generally observed at depths ranging from approximately 3½ to 5½ feet below ground surface as indicated on the enclosed boring logs. The measured depths to groundwater are recorded near the upper right- hand corner of each boring log included with this report. Groundwater measurements provided with this report are indicative of groundwater levels at the locations and at the time the borings/groundwater measurements were completed. Perched and/or trapped water may be encountered in more permeable zones in the subgrade soils at different times throughout the year. Perched water is commonly encountered in soils immediately overlying less permeable clay zones or seams. Fluctuations in ground water levels and in the location and amount of perched/trapped water may occur over time depending on variations in hydrologic conditions, irrigation activities on this and surrounding properties and other conditions not apparent at the time of this report. ANALYSIS AND RECOMMENDATIONS Preliminary Basement Design and Construction We provide the following information to assist the ownership group and/or the civil design engineers in the determination if an area wide underdrain system is required to allow for basement construction across the Willox Farms Development. Groundwater was encountered across the site within the five (5) supplemental MW/PZ’s borings at approximate depths of 3½ to 5½ feet below existing site grades. If lower level construction for full-depth basements is being considered for the site, we would suggest that the lower level subgrade(s) be placed a minimum of 3 feet above maximum anticipated rise in groundwater levels, or a combination exterior and interior perimeter drainage system(s) be installed. Consideration could also be given to 1) either designing and installing an area underdrain system to lower the groundwater levels provided a gravity discharge point can be established. If a Earth Engineering Consultants, LLC EEC Project No. 1212027 Supplemental Subsurface Exploration Report – Willox Farms Fort Collins, Colorado April 13, 2022 Page 6 gravity outlet/system cannot be designed another consideration would be to design and install a mechanical sump pump system to discharge the collected groundwater within the underdrain system, or 2) elevate/raise the site grades to establish the minimum required four (4) foot separation to the maximum anticipated rise in groundwater. EEC is available to assist in the underdrain design if requested. The following information should be considered, which was previously mentioned, would be to install an interior and exterior perimeter drainage system for each individual residence, regardless if an area wide underdrain system were to be designed and installed. To reduce the potential for groundwater to enter the lower level/basement area of the structure(s), installation of a dewatering system for each residence is recommended. The dewatering system should, at a minimum, include an underslab gravel drainage layer sloped to an interior perimeter drainage system. The following provides design recommendations for both interior and exterior perimeter drainage systems for each residence. The underslab drainage system should consist of a properly sized perforated pipe, embedded in free-draining gravel, placed in a trench at least 12 inches in width. The trench should be inset from the interior edge of the nearest foundation a minimum of 12 inches. In addition, the trench should be located such that an imaginary line extending downward at a 45-degree angle from the foundation does not intersect the nearest edge of the trench. Gravel should extend a minimum of 3 inches beneath the bottom of the pipe. The underslab drainage system should be sloped at a minimum 1/8 inch per foot to a suitable outlet, such as a sump and pump system. The underslab drainage layer should consist of a minimum 6-inch thickness of free-draining gravel meeting the specifications of ASTM C33, Size No. 57 or 67 or equivalent. Cross- connecting drainage pipes should be provided beneath the slab at minimum 15-foot intervals and should discharge to the perimeter drainage system. Sizing of drainage pipe will be dependent upon groundwater flow into the dewatering system. Groundwater flow rates will fluctuate with permeability of the soils to be dewatered and the depth to which groundwater may rise in the future. Pump tests to determine groundwater flow rates are recommended in order to properly design the system. For preliminary design purposes, the drainage pipe, sump and pump system should be sized for a projected flow of 0.5 x 10-3 cubic feet per second (cfs) per lineal foot of drainage pipe. Additional recommendations can be Earth Engineering Consultants, LLC EEC Project No. 1212027 Supplemental Subsurface Exploration Report – Willox Farms Fort Collins, Colorado April 13, 2022 Page 7 provided upon request and should be presented in final subsurface exploration reports for each residential lot. To reduce the potential for surface water infiltration from impacting foundation bearing soils and/or entering any planned below grade portion of any residential structure, installation of an exterior perimeter drainage system is recommended. This drainage system should be constructed around the exterior perimeter of the lower level/below grade foundation system and sloped at a minimum 1/8 inch per foot to a suitable outlet, such as a sump and pump system. The exterior drainage system should consist of a properly sized perforated pipe, embedded in free-draining gravel, placed in a trench at least 12 inches in width. Gravel should extend a minimum of 3 inches beneath the bottom of the pipe, and at least 2 feet above the bottom of the foundation wall. The system should be underlain with a polyethylene moisture barrier, sealed to the foundation walls, and extended at least to the edge of the backfill zone. The gravel should be covered with drainage fabric prior to placement of foundation backfill. Other Considerations and Recommendations Groundwater was observed at an approximate depth of 3½ to 5½ feet below present site grades. Excavations extending to the wetter soils could create difficulties for backfilling of the utility/pipe trenches with drying of the subgrade soils required to use those materials as backfill. In general, the subgrade soils could be used as backfill soils although care will be necessary to maintain sufficient moisture to reduce potential for post-construction movement. Excavations into the on-site soils will encounter a variety of conditions. Excavations into the clays can be expected to stand on relatively steep temporary slopes during construction; however, caving soils may also be encountered within the underlying granular soils, especially in close proximity to the groundwater table. Groundwater seepage should also be anticipated for utility excavations. Pumping from sumps may be utilized to control water within the excavations. Well points may be required for significant groundwater flow, or where excavations penetrate groundwater to a significant depth. The individual contractor(s) should be made responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom. All excavations should be sloped or Earth Engineering Consultants, LLC DRILLING AND EXPLORATION DRILLING & SAMPLING SYMBOLS: SS: Split Spoon ‐ 13/8" I.D., 2" O.D., unless otherwise noted PS: Piston Sample ST: Thin‐Walled Tube ‐ 2" O.D., unless otherwise noted WS: Wash Sample R: Ring Barrel Sampler ‐ 2.42" I.D., 3" O.D. unless otherwise noted PA: Power Auger FT: Fish Tail Bit HA: Hand Auger RB: Rock Bit DB: Diamond Bit = 4", N, B BS: Bulk Sample AS: Auger Sample PM: Pressure Meter HS: Hollow Stem Auger WB: Wash Bore Standard "N" Penetration: Blows per foot of a 140 pound hammer falling 30 inches on a 2‐inch O.D. split spoon, except where noted. WATER LEVEL MEASUREMENT SYMBOLS: WL : Water Level WS : While Sampling WCI: Wet Cave in WD : While Drilling DCI: Dry Cave in BCR: Before Casing Removal AB : After Boring ACR: After Casting Removal Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils, the indicated levels may reflect the location of ground water. In low permeability soils, the accurate determination of ground water levels is not possible with only short term observations. DESCRIPTIVE SOIL CLASSIFICATION Soil Classification is based on the Unified Soil Classification system and the ASTM Designations D‐2488. Coarse Grained Soils have move than 50% of their dry weight retained on a #200 sieve; they are described as: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are described as : clays, if they are plastic, and silts if they are slightly plastic or non‐plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse grained soils are defined on the basis of their relative in‐ place density and fine grained soils on the basis of their consistency. Example: Lean clay with sand, trace gravel, stiff (CL); silty sand, trace gravel, medium dense (SM). CONSISTENCY OF FINE‐GRAINED SOILS Unconfined Compressive Strength, Qu, psf Consistency < 500 Very Soft 500 ‐ 1,000 Soft 1,001 ‐ 2,000 Medium 2,001 ‐ 4,000 Stiff 4,001 ‐ 8,000 Very Stiff 8,001 ‐ 16,000 Very Hard RELATIVE DENSITY OF COARSE‐GRAINED SOILS: N‐Blows/ft Relative Density 0‐3 Very Loose 4‐9 Loose 10‐29 Medium Dense 30‐49 Dense 50‐80 Very Dense 80 + Extremely Dense PHYSICAL PROPERTIES OF BEDROCK DEGREE OF WEATHERING: Slight Slight decomposition of parent material on joints. May be color change. Moderate Some decomposition and color change throughout. High Rock highly decomposed, may be extremely broken. HARDNESS AND DEGREE OF CEMENTATION: Limestone and Dolomite: Hard Difficult to scratch with knife. Moderately Can be scratched easily with knife. Hard Cannot be scratched with fingernail. Soft Can be scratched with fingernail. Shale, Siltstone and Claystone: Hard Can be scratched easily with knife, cannot be scratched with fingernail. Moderately Can be scratched with fingernail. Hard Soft Can be easily dented but not molded with fingers. Sandstone and Conglomerate: Well Capable of scratching a knife blade. Cemented Cemented Can be scratched with knife. Poorly Can be broken apart easily with fingers. Cemented Group Symbol Group Name Cu≥4 and 1<Cc≤3E GW Well-graded gravel F Cu<4 and/or 1>Cc>3E GP Poorly-graded gravel F Fines classify as ML or MH GM Silty gravel G,H Fines Classify as CL or CH GC Clayey Gravel F,G,H Cu≥6 and 1<Cc≤3E SW Well-graded sand I Cu<6 and/or 1>Cc>3E SP Poorly-graded sand I Fines classify as ML or MH SM Silty sand G,H,I Fines classify as CL or CH SC Clayey sand G,H,I inorganic PI>7 and plots on or above "A" Line CL Lean clay K,L,M PI<4 or plots below "A" Line ML Silt K,L,M organic Liquid Limit - oven dried Organic clay K,L,M,N Liquid Limit - not dried Organic silt K,L,M,O inorganic PI plots on or above "A" Line CH Fat clay K,L,M PI plots below "A" Line MH Elastic Silt K,L,M organic Liquid Limit - oven dried Organic clay K,L,M,P Liquid Limit - not dried Organic silt K,L,M,O Highly organic soils PT Peat (D30)2 D10 x D60 GW-GM well graded gravel with silt NPI≥4 and plots on or above "A" line. GW-GC well-graded gravel with clay OPI≤4 or plots below "A" line. GP-GM poorly-graded gravel with silt PPI plots on or above "A" line. GP-GC poorly-graded gravel with clay QPI plots below "A" line. 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 Earth Engineering Consultants, LLC IIf soil contains >15% gravel, add "with gravel" to group name JIf Atterberg limits plots shaded area, soil is a CL- ML, Silty clay Unified Soil Classification System Soil Classification Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Sands 50% or more coarse fraction passes No. 4 sieve Fine-Grained Soils 50% or more passes the No. 200 sieve <0.75 OL Gravels with Fines more than 12% fines Clean Sands Less than 5% fines Sands with Fines more than 12% fines Clean Gravels Less than 5% fines Gravels more than 50% of coarse fraction retained on No. 4 sieve Coarse - Grained Soils more than 50% retained on No. 200 sieve CGravels with 5 to 12% fines required dual symbols: Kif soil contains 15 to 29% plus No. 200, add "with sand" or "with gravel", whichever is predominant. <0.75 OH Primarily organic matter, dark in color, and organic odor ABased on the material passing the 3-in. (75-mm) sieve ECu=D60/D10 Cc= HIf fines are organic, add "with organic fines" to group name LIf soil contains ≥ 30% plus No. 200 predominantly sand, add "sandy" to group name. MIf soil contains ≥30% plus No. 200 predominantly gravel, add "gravelly" to group name. DSands with 5 to 12% fines require dual symbols: BIf field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name.FIf soil contains ≥15% sand, add "with sand" to GIf fines classify as CL-ML, use dual symbol GC- CM, or SC-SM. Silts and Clays Liquid Limit less than 50 Silts and Clays Liquid Limit 50 or more 0 10 20 30 40 50 60 0 10 20 30 40 50 60 70 80 90 100 110PLASTICITY INDEX (PI) LIQUID LIMIT (LL) ML OR OL MH OR OH For Classification of fine-grained soils and fine-grained fraction of coarse-grained soils. Equation of "A"-line Horizontal at PI=4 to LL=25.5 then PI-0.73 (LL-20) Equation of "U"-line Vertical at LL=16 to PI-7, then PI=0.9 (LL-8) CL-ML WILLOX FARM FORT COLLINS, COLORADO EEC PROJECT NO. 1212027 APRIL 2022 PZ-1 PZ-2 PZ-3 PZ-4 MW-1 1 2 Monitoring Well and Piezometer Location Diagram Willox Farms Fort Collins, Colorado EEC Project #: 1212027 Date: April 2022 Approximate %oring Locations 1 EARTH ENGINEERING CONSULTANTS, LLC Legend Site PKotos PKotos taNen in approximate location, in direction oI arroZ 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:MW-1, S-2, at 9-10' Sample Desc.:Poorly Graded Sand with Gravel (SP) Date:April 2022 75 59 44 3 1.8 41 33 24 17 9 100 100 100 92 82 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium April 2022 25.00 4.95 3.28 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 MW-1, S-2, at 9-10' Poorly Graded Sand with Gravel (SP) D100 D60 D50 0.97 0.31 Fine 15.85 0.60 D30 D10 Cu CC 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:MW-1, S-3, at 10-11' Sample Desc.:Sandy Lean Clay (CL) / Clayey Sand (SC) Date:April 2022 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing 100 100 100 100 100 100 100 99 78 50.3 98 97 95 93 91 ------ Fine ------ D30 D10 Cu CC April 2022 9.50 0.10 --- Willox Farms Groundwater Study Fort Collins, Colorado 1212027 MW-1, S-3, at 10-11' Sandy Lean Clay (CL) / Clayey Sand (SC) D100 D60 D50 EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:MW-1, S-4, at 11-12' Sample Desc.:Well Graded Sand with Gravel (SW) Date:April 2022 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing 100 100 94 94 93 91 87 79 7 4.2 75 59 30 18 12 0.60 0.25 Fine 4.92 1.20 D30 D10 Cu CC April 2022 37.50 1.22 1.00 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 MW-1, S-4, at 11-12' Well Graded Sand with Gravel (SW) D100 D60 D50 EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-1, S-1, at 4' Sample Desc.:Well Graded Sand with Gravel (SW) Date:April 2022 77 72 64 11 6.2 61 50 32 24 18 100 100 85 80 78 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium April 2022 37.50 1.91 1.21 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-1, S-1, at 4' Well Graded Sand with Gravel (SW) D100 D60 D50 0.56 0.14 Fine 13.50 1.18 D30 D10 Cu CC 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-1, S-2, at 9' Sample Desc.:Poorly Graded Gravel (GP) Date:April 2022 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing 100 100 85 72 56 53 44 38 7 4.6 36 32 25 20 14 1.02 0.21 Fine 66.76 0.35 D30 D10 Cu CC April 2022 37.50 14.04 8.00 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-1, S-2, at 9' Poorly Graded Gravel (GP) D100 D60 D50 EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-2, S-1, at 4' Sample Desc.:Poorly Graded Gravel (GP) Date:April 2022 50 44 37 8 5.2 35 30 23 18 14 100 100 84 62 52 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium April 2022 37.50 17.90 10.00 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-2, S-1, at 4' Poorly Graded Gravel (GP) D100 D60 D50 1.17 0.19 Fine 93.65 0.40 D30 D10 Cu CC 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-3, S-1, at 4' Sample Desc.:Lean Clay with Sand (CL) Date:April 2022 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing 100 100 100 100 100 100 100 100 82 71.4 100 99 96 93 91 ------ Fine ------ D30 D10 Cu CC April 2022 4.75 ------ Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-3, S-1, at 4' Lean Clay with Sand (CL) D100 D60 D50 EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-3, S-2, at 9' Sample Desc.:Poorly Graded Gravel (GP) Date:April 2022 55 48 41 6 4.3 39 29 16 12 9 100 100 75 67 58 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium April 2022 37.50 14.10 6.14 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-3, S-2, at 9' Poorly Graded Gravel (GP) D100 D60 D50 1.25 0.33 Fine 42.77 0.34 D30 D10 Cu CC 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-4, S-1, at 4' Sample Desc.:Sand with Silt and Gravel (SM) Date:April 2022 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing 100 100 100 90 81 79 70 59 19 11.5 57 48 38 34 29 0.34 --- Fine ------ D30 D10 Cu CC April 2022 25.00 2.50 1.34 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-4, S-1, at 4' Sand with Silt and Gravel (SM) D100 D60 D50 EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size 2 1/2"(63 mm) 2"(50 mm) 1 1/2"(37.5 mm) 1"(25 mm) 3/4"(19 mm) 1/2"(12.5 mm) 3/8"(9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 10 (2 mm) No. 16 (1.18 mm) No. 30 (0.6 mm) No. 40 (0.425 mm) No. 50 (0.3 mm) No. 100 (0.15 mm) No. 200 (0.075 mm) Project:Willox Farms Groundwater Study Location:Fort Collins, Colorado Project No:1212027 Sample ID:PZ-4, S-2, at 9' Sample Desc.:Poorly Graded Sand with Gravel (SP) Date:April 2022 80 66 53 5 3.1 49 37 25 19 12 100 100 100 91 84 EARTH ENGINEERING CONSULTANTS, LLC SUMMARY OF LABORATORY TEST RESULTS Sieve Analysis (AASHTO T 11 & T 27 / ASTM C 117 & C 136) 100 Sieve Size Percent Passing EARTH ENGINEERING CONSULTANTS, LLC Summary of Washed Sieve Analysis Tests (ASTM C117 & C136) Date: Project: Location: Project No: Sample ID: Sample Desc.: Cobble Silt or ClayGravel Coarse Fine Sand Coarse Medium April 2022 25.00 3.65 2.11 Willox Farms Groundwater Study Fort Collins, Colorado 1212027 PZ-4, S-2, at 9' Poorly Graded Sand with Gravel (SP) D100 D60 D50 0.85 0.26 Fine 14.27 0.77 D30 D10 Cu CC 6" 5" 4" 3" 2.5" 2" 1.5" 1" 3/4" 1/2" 3/8" No. 4 No. 8 No. 10 No. 16 No. 30 No. 40 No. 50 No. 100 No. 200 0 10 20 30 40 50 60 70 80 90 100 0.010.11101001000Finer by Weight (%)Grain Size (mm) Standard Sieve Size