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PZ - Geotech Eval. I ENVIRONMENTAL TECHNICAL ALLWEST MATERIALSOTESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY June 9, 2023 Trilogy Development 9839 West Cable Car Street, Suite 101 Boise, Idaho 83709 Attention: Shawn Brownlee (shawn(a-)-trilogyidaho.com) RE: Geotechnical Evaluation South Eagle Road Development 7355 South Eagle Road Meridian, Idaho ALLWEST Project No. 523-087G Mr. Brownlee, ALLWEST has completed the authorized geotechnical evaluation for the proposed South Eagle Road Development to be located at 7355 South Eagle Road in Meridian, Idaho. The purpose of this evaluation was to characterize the subsurface conditions at the site and prepare the attached report with the results of our field evaluation and laboratory testing, and our geotechnical recommendations to assist planning, design, and construction of the proposed development. We appreciate the opportunity to provide services for this project. If you have any questions or need additional information, please contact us at (208) 895-7898. Sincerely, oQ�pFESSIpN" / O ALLWEST �� (o�Q'�2� %let% ' LENS KEVIN ANDREW ro Q �'4 /g DYEKMAN N0. 1727 14253 4pl-or lift eP OF to Kevin Dyekman, P.G. Adrian Mascorro, P.E HAIA Engineering Services Manager Area Manager 225 N. Linder Rd., Suite#100, Meridian, ID 83642 Phone: 208.895.7898 • Fax: 208.898.3959 Hayden, ID•Lewiston, ID• Meridian, ID•Spokane Valley,WA•Tri-Cities,WA• Missoula, MT www.allwesftesting.com GEOTECHNICAL EVALUATION SOUTH EAGLE ROAD DEVELOPMENT 7355 SOUTH EAGLE ROAD MERIDIAN, IDAHO ALLWEST PROJECT NO. 523-087G June 9, 2023 Prepared for: TRILOGY DEVELOPMENT 9839 WEST CABLE CAR STREET, SUITE 101 BOISE, IDAHO 83709 Prepared by: ALLWEST 255 NORTH LINDER ROAD, SUITE 100 MERIDIAN, IDAHO 83642 EXECUTIVE SUMMARY The following summarizes select geotechnical information/recommendations from this evaluation: ♦ We anticipate approximately 3 to 12 inches of site stripping will be required for most of the site to remove surficial vegetation and roots (topsoil). ♦ In general, subsurface soils within the observed test pits consisted of sandy lean clays, lean clays with sand, sandy silts, silts with sand, silty sands, poorly-graded sands, poorly-graded sands with silt, poorly-graded gravels with sand, poorly-graded gravels with silt and sand, poorly-graded gravels with sand and cobbles, and poorly-graded gravels with silt, sand, and cobbles. ♦ Varying amounts and thicknesses of weak to strong cementation and/or induration were commonly observed within the silty sand soil layers, as well as within select gravel and sand soil zones. ♦ Surficial undocumented fill soils were observed within test pits TP-6, -19, and -23 to depths of 1 to 2 feet below existing ground. Undocumented fill is not suitable to support site grading fill, pavement sections, or structural improvements. ♦ At the time of exploration,we did not observe groundwater within the test pits to the maximum exploration depth of 13 feet below existing ground. ♦ We recommend stormwater disposal occur within non-cemented/non-indurated poorly- graded gravel with sand; poorly-graded gravel with silt and sand; poorly-graded gravel with sand and cobbles; poorly-graded gravel with silt, sand, and cobbles; poorly-graded sand with silt; or poorly-graded sand soils (i.e., gravel/sand soils), as observed during our field exploration. A seepage rate of 8 inches per hour (in/hr) may be utilized for stormwater disposal into gravel/sand soils. ♦ For local roadways: Pavement sections should consist of 2.5-inches of asphalt concrete, over 4-inches of crushed aggregate base, over 11-inches of aggregate subbase. ♦ For collector roadways: Pavement sections should consist of 3-inches of asphalt concrete, over 6-inches of crushed aggregate base, over 14-inches of aggregate subbase. Our services were provided in accordance with ALLWEST proposal no. 523-087P dated February 20, 2023. This summary should be used in conjunction with the entire report for design and construction purposes. It should be recognized that details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLW EST AN EMPLOYEE-OWNED COMPANY GEOTECHNICAL EVALUATION SOUTH EAGLE ROAD DEVELOPMENT 7355 SOUTH EAGLE ROAD MERIDIAN, IDAHO Page 1.0 PROJECT DOCUMENTS.......................................................................................................1 2.0 PROJECT DESCRIPTION......................................................................................................1 3.0 EVALUATION PROCEDURES...............................................................................................1 4.0 SITE CONDITIONS ................................................................................................................2 4.1 Published Geologic and Soil Information ............................................................................2 4.2 Subsurface Soil Conditions .................................................................................................2 4.3 Groundwater Conditions......................................................................................................3 5.0 LABORATORY TESTING.......................................................................................................3 6.0 CONCLUSIONS AND RECOMMENDATIONS.......................................................................4 6.1 Site Preparation...................................................................................................................4 6.1.1 Subgrade Stabilization..................................................................................................5 6.1.2 Utility Trenches.............................................................................................................6 6.2 Excavation...........................................................................................................................6 6.3 Materials..............................................................................................................................7 6.4 Fill Placement and Compaction...........................................................................................8 6.5 Wet Weather Construction ..................................................................................................8 6.6 Cold Weather Construction .................................................................................................9 6.7 Stormwater and Drainage ...................................................................................................9 6.8 Asphalt Pavement .............................................................................................................10 7.0 ADDITIONAL RECOMMENDED SERVICES .......................................................................11 8.0 EVALUATION LIMITATIONS................................................................................................12 Appendix A—Vicinity Map, Exploration Location Map Appendix B —Test Pit Logs, Unified Soil Classification System Appendix C — Laboratory Test Results GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY GEOTECHNICAL EVALUATION SOUTH EAGLE ROAD DEVELOPMENT 7355 SOUTH EAGLE ROAD MERIDIAN, IDAHO 1.0 PROJECT DOCUMENTS The following project documents were reviewed by ALLWEST to help develop our understanding of the planned development: ♦ LandproDATA Parcel Map, Paragon Ventures, LLC, PSA ID#Brasher 60, dated February 8, 2023. ♦ Phase I Environmental Site Assessment, Coolwater Creek Subdivision, prepared by Atlas Technical Consultants, LLC, report viability date November 12, 2022. ♦ Cool Water Creek Subdivision Water Right Analysis, prepared by HDR/SPF, dated July 5, 2022. 2.0 PROJECT DESCRIPTION Based on communication with you and review of the provided documents, we understand that development will consist of an approximate 60-acre residential subdivision with associated infrastructure, stormwater disposal facilities, and asphalt-paved roadways. We did not review grading plans, as they were not available at the time of this proposal, but we anticipate cuts and fills for general site grading to be 3 feet or less. 3.0 EVALUATION PROCEDURES To complete this evaluation, we reviewed published geologic/soil information and observed the advancement of exploratory test pits on-site to evaluate the subsurface conditions. The general location of the site is shown on Figure A-1: Vicinity Map in Appendix A. We observed the excavation of 24 test pits (TP-1 through TP-24) on March 29 and 30, 2023, utilizing a Case 580C backhoe with a 24-inch-wide toothed excavation bucket. Test pits were advanced to maximum depths of 3 to 13 feet below existing ground. Maximum depths varied due to caving conditions and excavator refusal on strongly cemented soils encountered in select test pits. The approximate locations of the test pits are shown on Figure A-2: Exploration Location Map in Appendix A. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLW EST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 2 The soils observed in the test pits were visually described and classified in general accordance with ASTM D 2488. We logged the subsurface profiles and obtained soil samples at select depths for further identification and laboratory testing. We also performed 8 field seepage tests within select test pits throughout the site, where suitable permeable soils were encountered. Information obtained from the field evaluation, laboratory testing, and geotechnical analysis was utilized to develop the recommendations presented in this report. 4.0 SITE CONDITIONS At the time of exploration, the site consisted of partially developed pastureland and was occupied by the Coolwater Creek Events Center. The main event center building and outbuilding structures were located in the southeast corner of the site.Additionally,there were 3 old western-style saloon structures (each less than 500 square-feet) located near the existing pond in the western portion of the site. The site is generally bordered by South Eagle Road to the east, residential developments to the north, and undeveloped farmland to the west and south. 4.1 Published Geologic and Soil Information The geologic conditions at the site are mapped as Gravel of Amity Terrace (map symbol — Qag) on the Geologic Map of the Boise Valley and Adjoining Area, Western Snake River Plain, Idaho, by K.L. Othberg, and L.R. Stanford, 1992. This unit is described as sandy pebble and cobble gravel approximately 33 feet thick mantled by approximately 2 to 7 feet of loess. The USDA Natural Resources Conservation Service (NRCS), which classifies the upper 5 feet of soil, has mapped the site as Elijah silt loam, Pipeline silt loam, and Purdam silt loam. These soils consist of silt loam, silt clay loam, loam, cemented material, very and extremely gravelly sand, and stratified sand to loam. The parent materials of these soils include lacustrine deposits, loess, alluvium, silty alluvium, loess over sandy alluvium, and/or mixed alluvium. The soils encountered in test pits are generally consistent with published information. 4.2 Subsurface Soil Conditions At the time of exploration, the site contained approximately 3 to 12 inches of surficial roots and vegetation at the ground surface. Tree roots were also observed within select test pits down to depths of 1 to 1.5 feet. In general, subsurface soils within the observed test pits consisted of sandy lean clays, lean clays with sand, sandy silts, silts with sand, silty sands, poorly-graded sands, poorly-graded sands with silt, poorly-graded gravels with sand, poorly-graded gravels with silt and sand, poorly-graded gravels with sand and cobbles, and poorly-graded gravels with silt, sand, and cobbles. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 3 Varying thicknesses of weak to strong cementation and/or induration were commonly observed within the silty sand soil layers. Additionally, weak to moderate cementation was observed in select zones of the poorly-graded sands with silt, the poorly-graded gravels with sand, and the poorly-graded gravels with silt, sand, and cobbles. Surficial undocumented fills consisting of poorly-graded gravels with sand or poorly-graded gravels with silt, sand, and cobbles were observed within test pits TP-6, -19, and -23 to depths of 1 to 2 feet below existing ground. These fill soils were most likely placed during construction of existing dirt access roads and parking areas. Undocumented fills are not suitable to support site grading fill, pavement sections, or structural improvements. Detailed descriptions of the soils observed are presented on the individual test pit logs in Appendix B. The descriptive soil terms used on the test pit logs, and in this report, can be referenced by the Unified Soil Classification System (USCS). A summary of the USCS is included in Appendix B. The subsurface conditions may vary between exploration locations; such changes in subsurface conditions may not be apparent until construction. 4.3 Groundwater Conditions At the time of exploration, we did not observe groundwater within the test pits to the maximum exploration depth of 13 feet below existing ground. Based on our review of available well driller report in the site vicinity (from Idaho Department of Water Resources), we anticipate groundwater may be encountered at depths greater than 30 feet below ground surface. Groundwater in the area is typically influenced by local irrigation and existing canals, drains, and laterals. Groundwater may also be influenced by precipitation, on-site construction, and development to adjacent sites. Groundwater elevations will fluctuate throughout the different seasons of the year and will likely peak during snowmelt and irrigation seasons (March to October). We installed slotted PVC pipes within 18 of the test pits for future groundwater monitoring. ALLWEST is currently performing monthly groundwater monitoring to help establish the presence or absence of seasonal high groundwater throughout the site. 5.0 LABORATORY TESTING We performed laboratory testing to supplement field classifications and to assess some of the soil engineering properties and parameters. Laboratory testing included fines content(ASTM D1140), moisture content (ASTM D2216), liquid and plastic limits (ASTM D4318), and California bearing ratio (CBR) (ASTM D1883). The laboratory test results are included in Appendix C, and some results are also summarized on the test pit logs in Appendix B. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 4 6.0 CONCLUSIONS AND RECOMMENDATIONS Based on our field observations, testing, and evaluation, in our opinion the site is suitable for the planned development provided our recommendations are properly implemented. The following recommendations are presented to assist planning, design, and construction of the development relative to earthwork, utilities, stormwater disposal, and asphalt pavement section design. These recommendations are based on our understanding of the proposed development, the conditions observed within exploration locations, laboratory test results, and engineering analysis. If the proposed development changes or if unforeseen conditions are encountered during construction, we should be given the opportunity to review the new information and, if necessary, update our recommendations. 6.1 Site Preparation ♦ Prior to conducting site grading, surficial soil containing vegetation, roots, and organics should be removed below proposed site grading fill areas, pavement areas, structural areas, and any other development areas. In general, we anticipate approximately 3 to 12 inches of site stripping will be required for most of the site to remove surficial vegetation and roots (topsoil). ♦ Where trees are encountered and will be removed as part of the development, large root systems should be completely over-excavated and replaced with suitable fill soils. Tree root depths will not fully be known until construction, but we anticipate approximately 3 to 4 feet of over-excavation will be required to remove large tree root systems. ♦ Organic-rich, loose/soft, and/or wet soils associated with existing irrigation ditches/laterals are present on-site. These soils are not suitable to support site grading fill, pavement sections, or structural improvements. Within proposed development areas, these soils should be completely over-excavated to suitable native soils. ♦ Undocumented fill soils are not suitable to support site grading fill, pavement sections, or structural improvements. Within proposed development areas, existing undocumented fill soils should be over-excavated their entire depth down to suitable native soils, and replaced with site grading fill soils that are moisture-conditioned and compacted in accordance with the requirements provided in section 6.4 Fill Placement and Compaction. During exploration, we encountered surficial undocumented fills within test pits TP-6, -19, and -23 to depths of 1 to 2 feet below existing ground. ♦ Depths and lateral limits of over-excavation associated with unsuitable soils (organic-rich, loose/soft, and/or wet soils, as well as undocumented fills), may not fully be known until earthwork begins. The earthwork contractor should have continencies in place to ensure that these areas are fully over-excavated to suitable native soils within development areas. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 5 ♦ Loose test pit backfill will settle with time, so where any test pits are located below proposed pavement, structural, or any development areas, loose test pit backfill soil should be re-excavated its entire depth and replaced with suitably moisture-conditioned and compacted fill soils. Over-excavated soils can be reused to backfill the test pits, provided the soils are not overly saturated, and they can achieve the required compaction criteria as provided in section 6.4 Fill Placement and Compaction. Test pit locations observed by ALLWEST may be identified in the field by white-flagged stakes(if still present from pre-marking) and/or white PVC pipes (where installed for groundwater monitoring). Approximate test pit locations are shown on Figure A-2: Exploration Location Map. We recommend test pit areas be accurately surveyed so that they may be located and remediated prior to earthwork construction and development. ♦ After site stripping, over-excavations, loose test pit remediation, and prior to site grading, utility/roadway construction, or any other type of development, the exposed subgrades should be proof-rolled with a minimum 5-ton vibratory roller,with loaded dump trucks/front- end loaders, or with a vibratory hoe-pack, to confirm subgrade stability. This will also assist in identifying any soft subgrade areas. If native subgrades are observed to significantly deflect or pump, the subgrades should be over-excavated and replaced with properly compacted fill or stabilized as recommended in section 6.1.1 Subgrade Stabilization. 6.1.1 Subgrade Stabilization If needed, subgrades may be stabilized using geosynthetic (geogrid) or woven geotextile reinforcement in conjunction with imported granular structural fill. The required thicknesses of granular structural fill (used in conjunction with geogrid or woven geotextile reinforcement)will be dependent on the construction traffic loading (which is unknown at this time), the type of reinforcement (geogrid or woven geotextile), and subgrade conditions. Therefore, a certain degree of trial and error may be required during construction to verify recommended stabilization section thicknesses and reinforcement types. Geogrid reinforcement should consist of Tensar TX-160 or equivalent. Woven geotextile reinforcement should consist of Contech C200 or equivalent. Alternatives to these reinforcement types should be approved by the geotechnical engineer prior to use on site. The following recommendations are provided for subgrade stabilization using reinforcement materials. ♦ Subgrade soils that are disturbed by construction equipment (caused rutting or pumping) should be over-excavated down to undisturbed native soils, utilizing a smooth-blade bucket to limit further disturbance of native soils. Reinforcement materials should be placed on a properly prepared non-disturbed subgrade with smooth surface. ♦ If geogrid reinforcement is used, a minimum weight 4-ounce, non-woven filter fabric should first be placed on the properly prepared subgrade. The geogrid reinforcement should then GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 6 be placed directly on top of the filter fabric. The filter fabric and reinforcement materials should be unrolled in the primary direction of fill placement and should be over-lapped at least 3 feet or follow manufacturer's recommendations. Filter fabric is not required if a woven geotextile is used for reinforcement. ♦ The reinforcement materials should be pulled taut to remove slack. ♦ Construction equipment should not be operated directly on reinforcement materials. Granular structural fill should be placed from outside the excavation to create a pad to operate equipment on. We recommend a minimum of 12 to 18 inches of granular structural fill be placed over the reinforcement materials before operating construction equipment on the fill. Low pressure, track-mounted equipment should be used to place granular structural fill over the reinforcement materials. ♦ Granular structural fill placed directly over reinforcement materials should be properly moisture-conditioned prior to placement, and once placed, be statically rolled. This combination of reinforcement materials and granular structural fill is considered the "bridge" section over soft subgrades. ♦ After the first"bridge"section has been placed, the remaining structural fill materials above the "bridge" section should be compacted to structural fill criteria in section 6.4 Fill Placement and Compaction, utilizing vibratory compaction methods. ♦ Vibratory compaction should be discontinued if it reduces the subgrade stability. If compaction criterion is not met within the fill lift above the "bridge" section, the "bridge" section is not thick enough, and subgrade stabilization should be attempted again with a thicker"bridge" section. The geotechnical engineer or a representative of the geotechnical engineer should be on-site during subgrade stabilization to verify our recommendations are followed, and to provide additional recommendations, as needed. 6.1.2 Utility Trenches Existing subsurface soils should provide adequate support for utilities, provided utility subgrades are compacted utilizing vibratory methods, such as with a large vibratory hoe-pack. If utility pipe subgrades are soft, yielding, and/or saturated at the time of construction, subgrade over- excavation and replacement with competent structural fill may be required below utilities. If support soils yield and/or are saturated at the time of construction, we should be notified to observe these soils and provide additional recommendations, as necessary. 6.2 Excavation We anticipate the majority of the on-site soils can be excavated with typical excavation equipment. Excavation refusal due to strongly cemented soils was encountered within test pits TP-3, TP-5, GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 7 and TP-22 at depths of 3 to 5 feet. Excavation of strongly cemented soils may require larger excavation equipment, hydraulic breakers, and/or other techniques to achieve subgrade depths. Stability of temporary excavations is a function of many factors, including the presence and abundance of groundwater, the type and density of various soil strata, the depth of cut, surcharge loadings adjacent to the excavation, and the length of time the excavation remains open. It is exceedingly difficult under the variable circumstances to pre-establish a safe and "maintenance- free" temporary cut slope angle. Therefore, it is the responsibility of the contractor to maintain safe temporary slope configurations since the contractor is continuously at the job site, able to observe the nature and condition of the cut slopes, and able to monitor the subsurface materials and groundwater conditions encountered. Unsupported vertical slopes or cuts deeper than 4 feet are not recommended if worker access is necessary. The cuts should be adequately sloped, shored, or supported to prevent injury to personnel from local sloughing and spalling. The excavation should conform to applicable federal, state, and local regulations. Regarding trench wall support, the site soil is considered Type C soil according to Occupational Safety and Health Administration (OSHA) guidelines and therefore should not exceed a 1.5HAV (horizontal to vertical) temporary slope. 6.3 Materials Stripped soils containing vegetation or debris are only suitable for use in non-structural landscape areas. Existing on-site soils may be reused as site grading fill, provided they are stockpiled separately, they meet the criteria below, and they are moisture-conditioned and compacted as required in this report. Imported granular soils should be free of organics, debris, and other deleterious material and meet the following criteria. Import materials should be approved by ALLWEST prior to delivery to the site. Fill Type Criteria Site Grading Fill Maximum size <_ 6 inches; o 0 Retained on 3/4-inch sieve < 30/o; Liquid limit < 50/o Maximum size <_ 6 inches; Granular Structural Fill, Retained on 3/4-inch sieve < 30%; Granular Subbase Passing No. 200 sieve <_ 15%; Non-plastic Alternatively, meet ISPWC section 801 (6-inch max) Maximum size <_ 1 inch; Crushed Base Course Retained on %-inch sieve < 10%; Passing No. 200 sieve < 10%; Non-plastic Alternatively, meet ISPWC section 802 (Type I) Maximum size <_ 2 inches; Utility Trench Backfill Retained on 3/4-inch sieve < 30%; (above pipe bedding) Passing No. 200 sieve <_ 10%; Non-plastic Alternatively, meet ISPWC section 801 (3-inch max) GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 8 6.4 Fill Placement and Compaction Fill should be placed in lift thicknesses which are appropriate for the compaction equipment used. Typically, 8-to 12-inch-thick loose-lifts are appropriate for rubber-tire and steel-drum compaction equipment. Lift thickness should be reduced to 4 inches for hand-operated compaction equipment. Fill should be moisture-conditioned to within 2 percentage points of the optimum moisture content prior to placement to facilitate compaction. Fill should be compacted to the percentages of the maximum dry density, based on ASTM D 1557 (modified Proctor), presented in the table below. Fill Area Compaction N Subgrade' Proof-ro112 Site Grading Fill / Granular Structural Fill 95 Granular Subbase / Crushed Base Course 952 Utility Trench Backfill 922 'Subgrade stability should be verified and approved by a representative of the geotechnical engineer prior to any fill placement or construction. 2For roadway and utility trench construction only, the local governing jurisdiction may provide their own method of determining the maximum dry density and compaction requirements (including subgrade). We strongly recommend backfilling utility trench excavations with fill soils which meet the criteria in section 6.3 Materials, as on-site fine-grained soils (silts and clays) may be difficult to moisture- condition and compact in utility trenches. 6.5 Wet Weather Construction We recommend earthwork for the site be scheduled for the drier seasons of the year. If construction is undertaken in wet periods of the year, it will be important to slope the ground surface to provide drainage away from construction. If construction occurs during or immediately after excessive precipitation, it may be necessary to over-excavate and replace saturated subgrade soil, which might otherwise be suitable. The on-site soils are sensitive to disturbance when wet. If these soils become wet and unstable, we recommend construction traffic is minimized where these soils are exposed. Low ground- pressure (tracked) equipment should be used to minimize disturbance. Soft and disturbed subgrade areas should be excavated to undisturbed soil and backfilled with structural fill, compacted to requirements stated in this report. In addition, it should be noted the on-site soils tend to have notable adhesion when wet and may be easily transported off-site by construction traffic. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 9 6.6 Cold Weather Construction The on-site soils are frost susceptible. If site grading and construction are anticipated during cold weather, we recommend good winter construction practices be implemented. Snow and ice should be removed from excavated areas and fill areas, prior to additional earthwork or construction. Pavement and flatwork portions of the construction should not be placed on frozen ground, nor should the supporting soils be permitted to freeze during or after construction. Frozen soils should not be used as fill. If native subgrades, or suitably moisture-conditioned and compacted fill lifts, will be left exposed to freezing temperatures overnight, those areas should be protected with a minimum of 12 inches of loose soil, or covered with heated construction blankets, so construction subgrades do not freeze. Frozen soils should be removed prior to any fill placement or construction of any kind. Earthwork construction during cold inclement weather will require a higher level of attention and detail to achieve required construction and compaction criteria, and may lead to additional earthwork requirements and extended construction schedules. 6.7 Stormwater and Drainage During our exploration we performed field seepage testing in test pits TP-1, -4, -6, -8, -9, -13, -17, and -34 within non-cemented/non-indurated poorly-graded gravel- and poorly-graded sand-type soils (i.e., gravel/sand soils). We obtained field-measured seepage rates of greater than 15 inches per hour (in/hr) within the non-cemented/non-indurated gravel/sand soils. Varying thicknesses of weak to strong cementation and/or induration were commonly observed within the silty sand soil layers. Additionally, weak to moderate cementation was observed in select zones of the poorly-graded sands with silt, the poorly-graded gravels with sand, and the poorly-graded gravels with silt, sand, and cobbles. We do not recommend stormwater disposal be accomplished within cemented/indurated soils, as these soils typically exhibit poor and inconsistent seepage rates. Refer to the test pit logs in Appendix B to verify depths and contacts of soils which are not suitable for stormwater disposal. We recommend stormwater disposal occur within non-cemented/non-indurated poorly-graded gravel with sand; poorly-graded gravel with silt and sand; poorly-graded gravel with sand and cobbles; poorly-graded gravel with silt, sand, and cobbles; and poorly-graded sand with silt; or poorly-graded sand soils (i.e., gravel/sand soils), as observed during our field exploration. Based on field seepage test results and our experience with similar soil types, we recommend the following allowable seepage rate be utilized for on-site civil stormwater disposal design into non- cemented and non-indurated gravel/sand soils. ♦ Gravel/sand soils (non-cemented/indurated) ....................................... 8 in/hr GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 10 Stormwater disposal facilities should be constructed a minimum of 1 foot into the recommended receiving soil. Filter fabric should be properly utilized to separate native soils from stormwater disposal facility drain rock and filter sand materials to help prevent fine-soil migration into drainable/filtering media, as required by civil design. The proper separation from bottom of stormwater disposal facilities and seasonal high groundwater should be maintained. As such, groundwater monitoring should be performed to confirm the presence or absence of seasonal high groundwater. We installed slotted PVC pipes within 18 of the test pits for future groundwater monitoring. ALLWEST is currently performing monthly groundwater monitoring to help establish the presence or absence of seasonal high groundwater throughout the site. We recommend the final grading plan include slopes that direct stormwater run-off away from buildings and pavement areas to stormwater management systems. Water should not be allowed to infiltrate or pond adjacent to foundations or development areas. 6.8 Asphalt Pavement Prior to pavement section construction, the pavement subgrade should be proof-rolled as recommended in section 6.1 Site Preparation (or as recommended by local jurisdictions). Local and collector roadways should be designed for a 20-year Equivalent Single Axle Load (ESAL) of 33,000 and 370,000, respectively, which is equivalent to Traffic Index (TI) values of 6 and 8, respectively. If actual traffic conditions are different than what is stated, we should be notified so that we may modify our pavement section design. Based on existing site grades, we anticipate that the majority of pavement subgrade areas will consist of sandy lean clays, lean clays with sand, sandy silts, silts with sand, and/or silty sands. To evaluate pavement section design, we performed CBR testing on a sandy lean clay, where we obtained a CBR value of 7.3, which is approximately equivalent to an R-value of 15. The following flexible asphalt pavement sections were designed utilizing the AASHTO pavement methodology and our experience with local jurisdictions. Based on subgrade preparation requirements and design assumptions, we recommend the following pavement sections be utilized for subdivision roadway construction for local and collector roadways. Asphalt Crushed Granular Pavement Application Concrete Base Course Subbase (inches) (inches) (inches) Local Roadway 2.5 4 11 Collector Roadway 3 6 14 GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 11 Base course and subbase should conform to the material recommendations as noted in this report and should be placed over a properly prepared subgrade. Finished asphalt surfaces should slope no less than 2% to help reduce the potential for surface water to infiltrate into the underlying pavement sections and subgrade soils. If the overall site is relatively flat, then finished asphalt surfaces should be constructed with crowns that slope away at a minimum gradient of 2% toward stormwater collection areas. Crack maintenance on pavements should be performed at least every 3 years, or when cracking is evident. Crack sealing will help reduce surface water from infiltrating into the supporting soils. 7.0 ADDITIONAL RECOMMENDED SERVICES To maintain continuity and efficiency, we recommend ALLWEST be retained to provide observations and testing throughout earthwork construction. As an independent testing company, ALLWEST can document the recommendations included in this report are followed, provide quality control testing, and observe earthwork for conformance to project specifications. As a minimum, we recommend the following testing and observations be provided by ALLWEST: ♦ Observe site stripping, over-excavations, test pit remediation, and any other soil over- excavations and backfills. ♦ Observe subgrade proof-rolling and approve subgrades prior to fill/materials placement or roadway section/utility construction. ♦ Observe removal of disturbed soil and subgrade stabilization, if required. ♦ Observe stormwater disposal facility subgrades, confirm subsurface seepage rates by performing large-scale seepage testing within stormwater disposal facility locations, and observe overall stormwater disposal facility construction. ♦ Conduct compaction testing of any fill soils placed for general site grading, utility backfills, and pavements. ♦ Observe placement of/test asphalt for compaction, oil content, and gradation. If we are not retained to provide the recommended construction observation and testing services, we shall not be responsible for soil engineering-related construction errors or omissions. GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 523-087G South Eagle Road Development June 9, 2023 Meridian, Idaho Page 12 8.0 EVALUATION LIMITATIONS This report has been prepared to assist planning, design, and construction of the proposed South Eagle Road Development located at 7355 South Eagle Road in Meridian, Idaho. Reliance by any other party is prohibited without the written authorization of ALLWEST. Our services consist of professional opinions and conclusions made in accordance with generally accepted geotechnical engineering principles and practices in the local area at the time this report was prepared. This acknowledgement is in lieu of all warranties, express or implied. The following appendices complete this report: Appendix A—Vicinity Map, Exploration Location Map Appendix B —Test Pit Logs, Unified Soil Classification System Appendix C— Laboratory Test Results GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Appendix A A-1 : Vicinity Map A-2: Exploration Location Map GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLW EST AN EMPLOYEE-OWNED COMPANY (f JA _ -� �- ../�'� � — ray.. •�.• JIL _ _ ; • '• - I HERITAGE GROVE' -'WESTTBOISE. - r-4 gum : ` r luko E 1 184, ■ Now x.�i wo _ _ ,i•` �". '_.;� ' BOISE' BENCH ' MAPLE GROVE FRANKL•I N ' 84 fr —i-, '•.w, III, •i. yFe, i -- �- SOUTHW EA:-,A. ADA COUNTY ALLIANCE"- 84 s 1 .7 t . _ W hl �• .'. G[ Y 'f aA E Lake Hazel Rd •rw E Columbia Rd FIGURE A-1:VICINITY MAP GEOTECHNICAL EVALUATION SOUTHALLWEST ROAD DEVELOPMENT D. • MERIDIAN255 N.LINDER ROAD,SUITE 100 CLIENT:TRILOGY DEVELOPMENT ■ • . PHONE: f: •0: '• NO.: 1: D2023 Base Map:Google Earth .`. ■ TP-3 ■ TP-2 ■ TP-4 TP-5 ■ TP-6 ■ TP-1 .ram loop ., .. ..... F TP-12 1. r— - r ■ TP-10 r r r r.w t� •`- ,.tip.., T ■ TP-7 TP-11 r � d ■ TP-8 r ' " �.iA ` d Nor-W It TP-14 r TP-15 ■ TP-13 TP-16 TP-17 - '< �,d"� 1p TP-18 � .- �,* o �r R ° TP TP-ifr v v% 0 TP-24 - TP-23"., rE' FIGURE A-2: EXPLORATION LOCATION MAP LEGEND N GEOTECHNICAL EVALUATION 0 Approximate location of test pit observed by ALLWEST. -T ALLWEST SOUTH EAGLE ROAD DEVELOPMENT 0 250' 500' MERIDIAN, IDAHO * Slotted PVC pipe was installed in test pit. 255 N.LINDER ROAD,SUITE 100 CLIENT:TRILOGY DEVELOPMENT MERIDIAN IDAHO,83642 PHONE:(208)895-7898 FAX:(208)898-3959 PROJECT NO.:523-087G DATE:JUNE 2023 Appendix B Test Pit Logs Unified Soil Classification System GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY ALLWEST DATE STARTED: 3/30/2023 TP - 1 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'27.8628"(43.541073°) U U LONGITUDE(DEGREES):W-116°21'51.1812" (-116.364217°) U a u) TOTAL DEPTH:8.5' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native);dark brown,stiff, moist Significant roots and vegetation observed to 6 inches.Tree roots observed to 1.5 feet. CL 1 Silty SAND;tan,dense to very dense,dry 2 3 sM ...moderate to strong cementation observed throughout soil layer 41H. Poorly-graded GRAVEL with Silt, Sand,and Cobbles;tan,dense, moist ° 5 ...subrounded gravel and cobbles up to 6 inches in maximum o dimension ...moderate cementation observed from 4.5 to 6 feet ° 0 0 GP-GM 0 7 ° Field seepage test performed at 7 feet. Field seepage rate> 15 in/hr. 0 0 8 0 Test pit terminated at 8.5 feet due to practical excavation refusal on dense cobbles. 9 Slotted PVC pipe installed. 1 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/30/2023 TP - 2 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'29.4792"(43.541522°) U U LONGITUDE(DEGREES):W-116°21'46.2096" (-116.362836°) U u) TOTAL DEPTH: 10' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native);dark brown,stiff, moist Significant roots and vegetation observed to 6 cIL inches. 1 Silty SAND;tan,medium dense to dense,dry to moist 2 3 sM ...weak to moderate cementation observed throughout soil layer 4 5 6— Poorly-graded GRAVEL with Silt, Sand,and Cobbles; brown, dense,moist ° 7 ...subrounded gravel and cobbles up to 10 inches in maximum o dimension 0 0 $ GP-GM DU 0 9 0 DU 0 1 Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 3 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'30.9408"(43.541928°) U U LONGITUDE(DEGREES):W-116°21'41.2236" (-116.361451°) U u) TOTAL DEPTH:4' = SAMPLE w Q DESCRIPTION W NOTES cL Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. Silty SAND;tan,dense to very dense,moist 1 2 sm ...moderate to strong cementation observed throughout soil layer 3 4 Test pit terminated at 4 feet due to practical excavation refusal on strong cementation. 5 6 7 8 9 1 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 4 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'29.4684"(43.541519°) U U LONGITUDE(DEGREES):W-116°21'35.8344" (-116.359954°) U u) TOTAL DEPTH: 10' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 cIL inches. 1 Silty SAND;tan,medium dense to dense, moist 2 Passing No.200 sieve=20% Bag 2.5'-3' Moisture content= 18% 3 ...weak to moderate cementation observed throughout soil layer sm 4 5 Poorly-graded GRAVEL with Sand;tan, medium dense,moist 0 6 0 Q o� Field seepage test performed at 7 feet. 7 o Field seepage rate> 15 in/hr. � GP Q $ o� O Q o� 9 0 Q o� O 10— Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 5 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'29.1912"(43.541442°) U U LONGITUDE(DEGREES):W-116°21'30.7008" (-116.358528°) U u) TOTAL DEPTH:3' = SAMPLE CL w Q DESCRIPTION W NOTES cL Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. Silty SAND; light brown, medium dense to very dense,moist to dry 1 sm ...weak to strong cementation observed throughout soil lavyer 2 3 Test pit terminated at 3 feet due to practical excavation refusal on strong cementation. 4 5 6 7 8 9 1 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 6 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'29.2848"(43.541468°) U U LONGITUDE(DEGREES):W-116°21'26.4708" (-116.357353°) U u) TOTAL DEPTH: 10.5' = SAMPLE w Q o DESCRIPTION W NOTES Poorly-graded GRAVEL with Silt and Sand(Fill); brown,medium KXX Significant roots and vegetation observed to 6 dense,moist inches. FILL 1 Poorly-graded SAND with Silt(Native);tan, medium dense to dense,moist Passing No.200 sieve=7% Bag 1.5'-2' Moisture content=30% 2 sP-sm moderate cementation observed throughout soil layer 3 4— Poorly-graded GRAVEL with Sand;tan to gray,medium dense, moist ° 5 0 Q ° Bag 5.5'-6' Passing No.200 sieve=4% o Moisture content=6% 6 O Field seepage test performed at 6 feet. o Field seepage rate> 15 in/hr. 0 Q 7 0� GP Q o� 8 0 Q o� 9 Q o� 0 Q 1 °� Test pit terminated at 10.5 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/30/2023 TP - 7 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'25.152"(43.54032°) U U LONGITUDE(DEGREES):W-116°21'51.1452" (-116.364207°) U u) TOTAL DEPTH: 10' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native);dark brown,stiff, moist Significant roots and vegetation observed to 6 inches. CL 1 Silty SAND;tan,dense to very dense,dry to moist 2 sM ...moderate to strong cementation observed throughout soil layer 3 4 Poorly-graded GRAVEL with Silt, Sand,and Cobbles;tan,dense, dry to moist ° ...subrounded gravel and cobbles up to 8 inches in maximum o dimension 5 ...moderate cementation observed from 4 to 5.5 feet ° 0 ------------------------------------------------ 0 6 0 0 7 GP-GM 0 O 8 o O 0 9 0 0 10— Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/30/2023 TP - 8 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'25.0224"(43.540284°) U U LONGITUDE(DEGREES):W-116°21'46.17" (-116.362825°) U u) TOTAL DEPTH:9' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native);dark brown,stiff, moist Significant roots and vegetation observed to 6 cIL inches. 1 Silty SAND;tan,dense to very dense,dry to moist 2 ------------------------------------------------ SM 3 ...moderate to strong cementation observed from 2.5 to 4.5 feet 4 Poorly-graded GRAVEL with Silt, Sand,and Cobbles;tan,dense, moist 5 ...subrounded gravel and cobbles up to 8 inches in maximum o dimension o Field seepage test performed at 5.5 feet. Field seepage rate> 15 in/hr. 0 6 0 GP-GM o 7 0 0 0 0 0 0 9 Test pit terminated at 9 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 9 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'26.2356"(43.540621°) U U LONGITUDE(DEGREES):W-116°21'40.9356" (-116.361371°) U u) TOTAL DEPTH: 10' = SAMPLE w Q DESCRIPTION W NOTES cL Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. Sandy SILT; light brown,stiff, moist 1 ML 2 Silty SAND;tan,medium dense, moist 3 4 ...weak cementation observed throughout soil layer SM 5 6 Poorly-graded SAND with Silt;tan, medium dense,moist Passing No.200 sieve= 11 Bag 6' 6.5' Moisture content=6% Field seepage test performed at 6.5 feet. Field seepage rate> 15 in/hr. 7 SP-SM 8 Poorly-graded GRAVEL with Sand;tan, medium dense,moist o� O Q 9 GP ° O Q o� 10— Test pit terminated at 10 feet due to caving. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 10 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'25.278"(43.540355°) U U LONGITUDE(DEGREES):W-116°21'35.7048" (-116.359918°) 01 U u) TOTAL DEPTH: 11' = SAMPLE w Q DESCRIPTION W NOTES cL Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. SILT with Sand;light brown,firm, moist 1 MIL 2 3 Silty SAND;tan,medium dense, moist T. Passing No.200 sieve=30% Bag 3' 3.5' Moisture content= 15% 4 5 sM 6 7 Poorly-graded SAND with Silt;tan, medium dense,moist 8 9 SP-SM 1 1 Test pit terminated at 11 feet due to caving. Slotted PVC pipe installed. 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 11 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'25.2564"(43.540349°) U U LONGITUDE(DEGREES):W-116°21'30.6504" (-116.358514°) 01 U u) TOTAL DEPTH: 11' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 cIL inches. 1 Silty SAND;tan to light brown,medium dense to very dense, moist 2 3 4 5 6 sm ...weak to strong cementation observed throughout soil layer 7 Passing No.200 sieve= 19% Bag 7'-7.5' Moisture content=21% 8 9 1 1 Test pit terminated at 11 feet due to practical refusal on strong cementation. Slotted PVC pipe installed. 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 12 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'25.3212"(43.540367°) U U LONGITUDE(DEGREES):W-116°21'27.1944" (-116.357554°) 01 U u) TOTAL DEPTH: 13' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 cIL inches. 1 Silty SAND;tan to light brown,medium dense,dry to moist 2 3 ...weak cementation observed from 1 to 7 feet 4 5 sm 6 g ...weak induration observed from 7 to 9 feet 9 Poorly-graded GRAVEL with Sand;tan, medium dense,moist 0 Q 0 Q 1 GP ° O Q o� 1 O °b 0 Q 1 Test pit terminated at 13 feet. Slotted PVC pipe installed. 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/30/2023 TP - 13 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'21.5376"(43.539316°) U U LONGITUDE(DEGREES):W-116°21'51.0624" (-116.364184°) 01 U u) TOTAL DEPTH: 12' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native);dark brown,stiff, moist Significant roots and vegetation observed to 6 cL inches. Silty SAND; brown,dense to very dense, moist 1 2 3 ------------------------------------------------ ...becomes tan at 3 feet 4 5 sM 6 ...moderate to strong cementation observed from 3 to 9.5 feet 7- 8- 9 Poorly-graded GRAVEL with Silt, Sand,and Cobbles;tan,dense Passing No.200 sieve=7% moist o Bag 9.5' 10' Moisture content=3% 1 o Field seepage test performed at 10 feet. DG Field seepage rate> 15 in/hr. 0 GP-GM O 1 0 0 1 Test pit terminated at 12 feet. Slotted PVC pipe installed. 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/30/2023 TP - 14 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'22.4988"(43.539583°) U U LONGITUDE(DEGREES):W-116°21'45.1296" (-116.362536°) 01 U u) TOTAL DEPTH:8' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native);dark brown,stiff, moist Significant roots and vegetation observed to 12 inches. 1 cL Passing No.200 sieve=53% Bag 1'-1.5' Moisture content=26% LL=45, PL= 19,PI=26 2 Poorly-graded GRAVEL with Silt, Sand,and Cobbles;tan,dense, moist ...subrounded gravel and cobbles up to 10 inches in maximum o dimension 3 0 0 0 4 ...becomes red-brown at 4 feet o DG 0 5 GP-GM DG DG 6 0 0 0 7 0 0 8 Test pit terminated at 8 feet due to caving. Slotted PVC pipe installed. 9 1 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 15 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'21.9048"(43.539418°) U U LONGITUDE(DEGREES):W-116°21'41.1732" (-116.361437°) 01 U u) TOTAL DEPTH: 11' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 cL inches. 1 SILT with Sand;light brown,stiff, moist MIL 2 Silty SAND;tan,dense to very dense,moist 3 sM ...moderate to strong cementation observed throughout soil layer 4 5 Poorly-graded GRAVEL with Sand;light brown,dense, moist 0 O 6 0 O o� 7 0 O o� 8 GP Q o� O O 9 0 O 1 O 1 Test pit terminated at 11 feet due to caving. 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 16 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'21.6096"(43.539336°) U U LONGITUDE(DEGREES):W-116°21'34.3188" (-116.359533°) 01 U u) TOTAL DEPTH: 10' = SAMPLE w Q DESCRIPTION W NOTES cL Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. Silty SAND;tan,dense to very dense,moist to dry 1 2 sm ...moderate to strong cementation observed throughout soil layer 3 4 5 Poorly-graded GRAVEL with Sand and Cobbles;tan, medium dense,moist ° ...subrounded gravel and cobbles up to 12 inches in maximum o dimension Q 6 0 Q o� 7 0 Q GP 0 $ Q o� O Q 9 0 Q 0 10— Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 17 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'21.6348"(43.539343°) U U LONGITUDE(DEGREES):W-116°21'30.24" (-116.3584°) 01 U u) TOTAL DEPTH: 10' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. CL Passing No.200 sieve=64% 1 Bulk 0.5'-1.5' ILL=37, PL=24,PI= 13 CBR=7.3 Silty SAND;tan,dense to very dense,dry to moist 2 sM ...moderate to strong cementation observed throughout soil layer 3 4 Poorly-graded GRAVEL with Silt and Sand;tan,medium dense, moist 0 5 0 0 o Bag 5.5'-6' Passing No.200 sieve=6% Moisture content=6% 6 o Field seepage test performed at 6 feet. Field seepage rate> 15 in/hr. 0 7—GP-GM O 0 O 8 o O 0 9 0 0 10— Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 18 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'21.2316"(43.539231°) U U LONGITUDE(DEGREES):W-116°21'26.8848" (-116.357468°) 01 U u) TOTAL DEPTH: 11' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 cIL inches. 1 Silty SAND;tan,dense,moist 2 Passing No.200 sieve=26% Bag 2'-2.5' Moisture content= 12% sm ...moderate cementation observed throughout soil layer 3 4 Poorly-graded GRAVEL with Sand;tan, medium dense,moist o� O O 5 0 O o� 6 0 O o� 7 O o� GP O O $ o� O O 9 O o� 1 O o� 0 O 1 Test pit terminated at 11 feet due to caving. Slotted PVC pipe installed. 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/30/2023 TP - 19 DATE FINISHED: 3/30/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Kevin Dyekman WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'17.9664"(43.538324°) U U LONGITUDE(DEGREES):W-116°21'46.422" (-116.362895°) 01 U u) TOTAL DEPTH: 11' = SAMPLE w Q DESCRIPTION W NOTES Poorly-graded GRAVEL with Silt, Sand,and Cobbles(Fill);tan, Significant roots and vegetation observed to 6 medium dense, moist inches. ...subrounded gravel and cobbles up to 12 inches in maximum 00( dimension 00( 1 FILL 00( 00( 2 Silty SAND(Native); brown, medium dense to very dense,moist 3 Passing No.200 sieve= 18% Bag 3'-3.5' Moisture content= 17% 4 5 ...weak to moderate cementation observed from 2 to 8 feet sM 6 7 g ------------------------------------------------ ...strong cementation observed from 8 to 9 feet 9 Poorly-graded GRAVEL with Silt, Sand,and Cobbles;red-brown, dense,moist 0 1 GP-GM 0 O 0 1 Test pit terminated at 11 feet due to caving. Slotted PVC pipe installed. 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 20 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'18.2328"(43.538398°) U U LONGITUDE(DEGREES):W-116°21'41.9796" (-116.361661°) 01 U u) TOTAL DEPTH: 10' = SAMPLE a o_ Lu DESCRIPTION W NOTES Lean CLAY with Sand(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches.Tree roots observed to 1 foot. Passing No.200 sieve=72% Bag 0.5'-1' Moisture conent=25% 1 cL LL=49, PL= 19,PI=30 2 Silty SAND;tan,dense to very dense,moist 3 Passing No.200 sieve=23% Bag 3.5' 4' Moisture conent=22% 4 sM ...moderate to strong cementation and induration observed throughout soil layer 5 6 Poorly-graded GRAVEL with Silt and Sand;tan,dense,moist Passing No.200 sieve= 10% o Bag 6'-6.5' Moisture conent= 15% 0 7—GP-GM ° O 0 8 Poorly-graded GRAVEL with Sand;tan,dense, moist o� O Q 9 GP ° O Q o� 1 Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 21 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'18.3516"(43.538431°) U U LONGITUDE(DEGREES):W-116°21'36.234" (-116.360065°) 01 U u) TOTAL DEPTH: 12' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. 1 cL 2 Silty SAND;tan,medium dense to dense,dry to moist 3 4 sm ...weak to moderate cementation observed throughout soil layer 5 6 Poorly-graded GRAVEL with Sand;tan, medium dense,...-.-. o� O O 7 0� O O o� O O o� 9 GP Q o� O O 1 0 O 1 O o� 1 Test pit terminated at 12 feet. Slotted PVC pipe installed. 1 1 -75 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION T AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 22 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'18.924"(43.53859°) U U LONGITUDE(DEGREES):W-116°21'29.8764" (-116.358299°) 01 U u) TOTAL DEPTH:4' = SAMPLE w Q DESCRIPTION W NOTES Sandy Lean CLAY(Native); brown,stiff, moist Significant roots and vegetation observed to 6 inches. 1 cL 2 Silty SAND;tan,dense to very dense,dry to moist 3 snn ...moderate to strong cementation observed throughout soil layer 4 Test pit terminated at 4 feet due to practical excavation refusal on strong cementation. 5 6 7 8 9 1 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 23 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'16.0008"(43.537778°) U U LONGITUDE(DEGREES):W-116°21'23.9616" (-116.356656°) 01 U u) TOTAL DEPTH: 12' = SAMPLE a CL Lu DESCRIPTION W NOTES Poorly-graded GRAVEL with Sand(Fill);tan,medium dense, Significant roots and vegetation observed to 3 moist inches. 00( 00( 1 FILL 00( 00( — I N 2 Sandy SILT(Native); brown,stiff, moist Passing No.200 sieve=57% Bag 2'-2.5' Moisture content=23% MIL 17 3 Poorly-graded SAND with Silt; light brown,very dense to dense, moist 4 5 Passing No.200 sieve=9% Bag 5'-5.5' Moisture content= 19% sP-sM ...strong to weak cementation observed throughout soil layer 6 7 8 Poorly-graded GRAVEL with Sand;tan, medium dense,moist o� O Q 9 GP ° O Q o� 1 Poorly-graded SAND;tan, medium dense,moist gag 10'-10.5' 1 SIR 1 Test pit terminated at 12 feet. Slotted PVC pipe installed. 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 3/29/2023 TP - 24 DATE FINISHED: 3/29/2023 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR:Steve Just EXCAVATION METHOD:24-inch-bucket GEOTECHNICAL SECTION COMPANY:Just Dig'It Exc. TEST PIT LOG LOGGER:Parker Norris WEATHER:Cloudy PROJECT:523-087G NOTES:See Figure A-2 in Appendix A for approximate test pit location. South Eagle Road Development LATITUDE(DEGREES):N 43°32'16.2276"(43.537841°) U U LONGITUDE(DEGREES):W-116°21'16.722" (-116.354645°) 01 U u) TOTAL DEPTH: 10.5' = SAMPLE a CL Lu DESCRIPTION W NOTES Poorly-graded GRAVEL with Sand and Cobbles(Native);tan, Significant roots and vegetation observed to 3 medium dense, moist ° inches. ...subrounded gravel and cobbles up to 12 inches in maximum o dimension O 1 ...weak cementation observed from 0.5 to 1.5 feet 0 ------------------------------------------------ Q 0 2 0 O 0 3 O 0 O O 4 °� O Bag4.5'-5' 0 Field seepage test performed at 5 feet. 5 GP O Field seepage rate> 15 in/hr. 0 0 6 Q 0 O O 7 0� O O $ 0 O O 0 9- 0 O O 1 °� Test pit terminated at 10.5 feet due to caving. 1 1 1 1 WATER LEVELS a WHILE EXCAVATING Y AT COMPLETION 1 AFTER EXCAVATING Sheet 1 of 1 Unified Soil Classification System MAJOR DIVISIONS SYMBOL TYPICAL NAMES Well-Graded Gravel, CLEAN GW Gravel-Sand Mixtures. GRAVELS GP Poorly-Graded Gravel, GRAVELS Gravel-Sand Mixtures. Silty Gravel, COARSE GRAVELS GM Gravel-Sand-Silt Mixtures. GRAINED WITH FINES GC Clayey Gravel, SOILS Gravel-Sand-Clay Mixtures. Well-Graded Sand, CLEAN SW Gravelly Sand. SANDS Sp Poorly-Graded Sand, SANDS Gravelly Sand. SM Silty Sand, I SANDS Sand-Silt Mixtures. I WITH FINES SC Clayey Sand, I Sand-Clay Mixtures. ML Inorganic Silt, SILTS AND CLAYS Silty or Clayey Fine Sand. Inorganic Clay of Low to LIQUID LIMIT CL Medium Plasticity, LESS THAN 50% Sandy or Silty Clay. FINE OL Organic Silt and Clay of Low GRAINED Plasticity. SOILS Inorganic Silt, Elastic Silt, SILTS AND CLAYS MH Micaceous Silt, Fine Sand or Silt. LIQUID LIMIT CH Inorganic Clay of High Plasticity, GREATER THAN 50% Fat Clay. OH Organic Clay of Medium to High Plasticity. Highly Organic Soils PT Peat, Muck and Other Highly Organic Soils. ALLWEST Appendix C Laboratory Test Results GEOTECHNICAL I ENVIRONMENTAL MATERIALS TESTING I SPECIAL INSPECTION ALLWEST AN EMPLOYEE-OWNED COMPANY Table C-1: Summary of Laboratory Test Results Gradation Atterberg Limits Depth Test Pit Content Gravel Sand Silt/Clay De Moisture p Liquid Plastic Plasticity CBR Sample Classification o (Feet) N N N N Limit Limit Index (�o) (USCS) (/o) (/o) (/o) TP-4 2.5-3 18 20 Silty SAND (SM) TP-6 1.5-2 30 7 Poorly-graded SAND with Silt(SP-SM) TP-6 5.5-6 6 4 Poorly-graded GRAVEL with Sand (GP) TP-9 6-6.5 6 11 Poorly-graded SAND with Silt(SP-SM) TP-10 3-3.5 15 30 Silty SAND (SM) TP-11 7-7.5 21 19 Silty SAND(SM) TP-13 9.5- 10 3 7 Poorly-graded GRAVEL with Silt, Sand, and Cobbles(GP-GM) TP-14 1 - 1.5 26 53 45 19 26 Sandy Lean CLAY(CL) TP-17 0.5- 1.5 1 64 37 24 13 7.3 Sandy Lean CLAY(CL) TP-17 5.5-6 6 6 Poorly-graded GRAVEL with Silt and Sand (GP-GM) TP-18 2-2.5 12 26 Silty SAND (SM) TP-19 3-3.5 17 1 18 Silty SAND(SM) TP-20 0.5- 1 25 72 49 19 30 Lean CLAY with Sand (CL) TP-20 3.5-4 22 23 Silty SAND(SM) TP-20 6-6.5 15 10 Poorly-graded GRAVEL with Silt and Sand (GP-GM) TP-23 2-2.5 23 57 Sandy SILT(ML) TP-23 5-5.5 19 9 Poorly-graded SAND with Silt(SP-SM) 255 N. Linder Road, Suite 100• Meridian, Idaho 83642• (208)895-7895• Fax(208)898-3959 www.allwesttesting.com This report may not be reproduced, except in full,without the permission of ALLWEST. LIQUID AND PLASTIC LIMITS TEST REPORT 60 Dashed line indicates the approximate upper limit boundary for natural soils 50 O �0 ' G 40 U C � X W N— Z_ � v 30 c F- LU C/) ' Q i J / a: 20 H U) LU J / J Q 10 0 ; c L-ML ML or OL MH or OH 0 0 10 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT 0 MATERIAL DESCRIPTION LL PL PI %<#40 %<#200 USCS • Sandy Lean Clay 45 19 26 53% CL c■ Sandy Lean Clay 37 24 13 64% CL CD♦ Lean Clay with sand 49 19 30 72% CL X m m U 7 O ` Project No. 523-087G Client: Trilogy Development Remarks: aD Project: South Eagle Road Development c *Location: TP-14 Depth: 1'-1.5' ■Location: TP-17 Depth: 0.5'-1.5' ALocation: TP-20 Depth: 0.5'-l' 0 cn ALLWEST Figure C-1 Tested By: C. Downes Checked By:J.Varozza California Bearing Ratio ASTM D1883 Project: South Eagle Road Development Project No.: 523-087G Client: Trilogy Development Location: TP-17 @ 0.5- 1.5 ft Date Tested: 4/17/2023 Compaction Method: ASTM D1557 Tested By: C. Downes Classification: Sandy Lean Clay (CL) 165 150 135 120 105 c 0 r a 90 c 0 y 75 v L N 60 PSI @ 0.1 inch penetration = 73 45 30 15 0 0 0.1 0.2 0.3 0.4 0.5 Penetration(inches) CBR @ 0.1 Inch Penetration: 7.3 Maximum Dry Unit Weight (pcf): 114.7 Swell (%): 2.7 Optimum Water Content (%): 11.7 Dry Unit Weight Before Soak (pcf): 98.8 Remold of Max. Dry Unt Wgt (%): 86 Water Content Before Soak (%): 16.1 Water Content After Soak, Top 1 Inch (%): 29.5 Surcharge (psf): 50 Immersion Period (hrs): 96 Reviewed By: James Varozza Figure: C-2 ACXLLWEST 255 N Linder Rd,Suite 100•Meridian, ID 83642•(208)895-7898•Fax(208)898-3959 www.allwesttesting.com This report shall not be reproduced except in full without the permission of ALLWEST.