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PZ - Geotech Report TECH ALLWEST MATERIALS OTESTI G I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY March 25, 2022 Katie Miller Bailey Engineering, Inc. 1119 East State Street, Ste. 210 Eagle, Idaho 83616 'prCr h a en ineers.com RE: Geotechnical Evaluation Modern Craftsman Eagle Road Development South Eagle Road Meridian, Idaho ALLWEST Project No. 521-497G Ms. Miller: ALLWEST has completed the authorized geotechnical evaluation for the proposed Modern Craftsman Eagle Road Development to be located along the east side of South Eagle Road, approximately 300 to 1,000 feet south of East Easy Jet Drive, in Meridian, Idaho. The purpose of this evaluation was to characterize subsurface soil conditions at the site and provide geotechnical recommendations to assist planning, design, and construction of the proposed development. Based on our evaluation, the site is suitable for the planned development, provided our recommendations herein are adhered to. The attached report presents the results of our field evaluation, laboratory testing, and our geotechnical recommendations. We appreciate the opportunity to be of service to Bailey Engineering, Inc. If you have any questions or need additional information, please contact us at(208) 895-7898. Sincerely, ALLWEST ^ 'JIM 14253 Adrian Mascorro, P.E. �OF I'D�D� Kevin Dyekman, P.G. Area Manager Ma Senior Engineering Geologist 255 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• Missoula, MT www.allwesttesting.com GEOTECHNICAL EVALUATION MODERN CRAFTSMAN EAGLE ROAD DEVELOPMENT SOUTH EAGLE ROAD MERIDIAN, IDAHO ALLWEST PROJECT NO. 521 -497G March 25, 2022 Prepared for: Bailey Engineering, Inc. 1119 East State Street, Ste. 210 Eagle, Idaho 83616 Prepared By: ALLWEST 255 North Linder Road, Suite 100 Meridian, Idaho 83642 ALLWEST WWW.ALLWESTTESTING.COM TABLE OF CONTENTS ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Meridian, Idaho Page 1.0 SCOPE OF SERVICES ........................................................................................ 1 2.0 PROJECT UNDERSTANDING............................................................................. 1 3.0 FIELD EVALUATION PROCEDURES.................................................................2 4.0 SITE CONDITIONS ..............................................................................................2 4.1 General Geologic Conditions.............................................................................2 4.2 General Soil Conditions..................................................................................... 3 5.0 EXPLORATION AND SAMPLING .......................................................................3 5.1 Subsurface Soil Conditions ............................................................................... 3 5.2 Subsurface Water.............................................................................................. 3 6.0 LABORATORY TESTING ....................................................................................4 7.0 CONCLUSIONS AND RECOMMENDATIONS ....................................................4 7.1 Grading and Drainage.......................................................................................4 7.2 Site Preparation.................................................................................................4 7.3 Subgrade Stabilization ...................................................................................... 6 7.4 Excavation......................................................................................................... 7 7.5 Materials............................................................................................................ 7 7.6 Fill Placement and Compaction......................................................................... 8 7.7 Utility Trenches.................................................................................................. 8 7.8 Wet Weather Construction ................................................................................ 8 7.9 Cold Weather Construction ............................................................................... 9 7.10 Stormwater Disposal ....................................................................................... 9 7.11 Asphalt Pavements ....................................................................................... 10 8.0 ADDITIONAL RECOMMENDED SERVICES..................................................... 11 9.0 EVALUATION LIMITATIONS............................................................................. 11 Appendix A— Site Vicinity Map, Exploration Location Plan Appendix B —Test Pit Logs, Unified Soil Classification System Appendix C— Laboratory Test Results GEOTECHNICAL I ENVIRONMENTAL ALL'WEST MATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 1 Meridian, Idaho Geotechnical Evaluation Modern Craftsman Eagle Road Development Meridian, Idaho ALLWEST has completed the geotechnical evaluation for the proposed Modern Craftsman Eagle Road Development to be located in Meridian, Idaho. The general location of the site is shown on Figure A-1: Site Vicinity Map in Appendix A of this report. The purpose of this evaluation was to identify subsurface soil conditions at the site and provide opinions and recommendations for the proposed development. This report details the results of our evaluation and presents recommendations relative to earthwork, utilities, stormwater disposal, and pavement section design to assist development. 1.0 SCOPE OF SERVICES Our scope of services for the project included the following: 1) Prior to subsurface exploration, we visited the site to observe accessibility and to pre-mark exploration locations, as required by Idaho Digline. 2) Notified Idaho Digline to locate on-site utilities, as required by Idaho state law. 3) Subcontracted a backhoe and operator to observe the excavation of 11 test pits throughout the site. 4) Visually described, classified, and logged the soils encountered within test pits and obtained soil samples within select test pits. 5) Performed seepage tests within select test pits to evaluate subsurface seepage and installed slotted PVC pipe within select test pits for future groundwater monitoring. 6) Performed laboratory tests on select soil samples to assess soil engineering properties and characteristics. 7) Reviewed the results of the field evaluation and laboratory testing, performed engineering analyses, and prepared this report with field and laboratory results, subsurface logs, and geotechnical-related opinions and recommendations. We provided our services for the project in general accordance with our geotechnical proposal (521-497P) dated October 5, 2021. 2.0 PROJECT UNDERSTANDING Based on electronic communication with you and review of the Conceptual Plan for Modern Craftsman Eagle Road prepared by Bailey Engineering, Inc. dated September 5, 2021, we understand the approximate 13.6-acre site may consist of 1- to 2-story single- and multi-family buildings/townhomes, a commercial parcel, and a pool/clubhouse area. The development will also contain associated infrastructure, stormwater disposal facilities, and asphalt-paved roadways, access lanes, and parking. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 2 Meridian, Idaho Existing structures and any associated infrastructure within the site are anticipated to be demolished as part of the development. We did not review grading or structural plans, as they were not available at the time of this proposal, but we anticipate cuts and fills for site grading to be 2 feet or less. This evaluation does not include recommendations for foundation construction. If foundation-related construction recommendations are required, we can provide that information on a building-by-building basis once we have had the opportunity to review final development and structural/foundation plans. Any additional recommendations, if requested, will be provided on a time-and-expense basis, and may require additional exploration, laboratory testing, and analysis. 3.0 FIELD EVALUATION PROCEDURES On November 10, 2021, we observed the excavation of 11 test pits to maximum depths of 7 to 13 feet below existing ground surfaces. Maximum depths of test pits varied due to caving conditions and excavator refusal on very dense cobbles/boulders. We identified subsurface soil conditions, logged the subsurface soil profiles, and obtained select soil samples for laboratory testing. We performed field seepage testing at select depths within 5 test pits to help evaluate subsurface soil seepage. At completion of exploration, the test pits were loosely backfilled with excavated soil approximately level with existing ground surfaces. Approximate test pit locations are shown on Figure A-2: Exploration Location Plan in Appendix A. 4.0 SITE CONDITIONS At the time of exploration, the overall site contained multiple residential and outbuilding- type structures with multiple fences and corralled areas along the western half of the site (adjacent to South Eagle Road), and undeveloped pasture/land within the eastern half of the site. A shallow ditch transects the site from the southeast corner to the northern portion of the site in a general northwest direction. The overall site is generally bordered by an existing subdivision to the north and east, current assisted living facility construction to the south, and South Eagle Road to the west. 4.1 General Geologic Conditions The geologic conditions at the site are mapped as Gravel of Gowan Terrace (Qgg) on the "Geologic Map of the Boise Valley and Adjoining Area, Western Snake River Plain, Idaho" by Othberg and Stanford (1992). These soils are described as sandy pebble and cobble gravel of the fourth terrace above the flood plain that is mantled by 3 to 7 feet of loess. The soils encountered in test pits are generally consistent with geologic mapping. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 3 Meridian, Idaho 4.2 General Soil Conditions The USDA Natural Resources Conservation Service (NRCS), which represents the upper 5 feet of soil profile, has mapped the soils on the site as Elijah silt loam. These soils generally consist of silt loam, silty clay loam, loam, cemented material, and extremely gravelly sand. Parent materials include lacustrine deposits, loess, and/or alluvium. The soils encountered in test pits are generally consistent with NRCS mapping. 5.0 EXPLORATION AND SAMPLING We observed the excavation of test pits with a Case 580C rubber-tired backhoe with a 2- foot-wide bucket. We visually described the soils encountered within test pits referencing ASTM D 2488, which utilizes the Unified Soil Classification System (USCS), and we obtained soil samples at select depths for further identification and laboratory testing. We performed field seepage testing within 5 test pits. We identified test pit locations on-site with white PVC pipes and/or stakes with white flagging. We obtained Google Earth latitude and longitude coordinates of test pit locations with a hand-held cellular device. These coordinates can be found on individual test pit logs in Appendix B and should be considered accurate to the degree implied by the method used. 5.1 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. In general, native subsurface soils within the observed test pits consisted of surficial lean clay with sand, underlain by varying thicknesses of sandy silt, sand, and gravel soils with depth. Varying levels of cementation and induration were observed within the sandy silt, sand, and gravel soil layers. Detailed soil descriptions, depths, and notes are presented on individual test pit logs in Appendix B. The descriptive soil terms used on the test pit logs, can be referenced by the USCS. A copy of the USCS is included in Appendix B. Subsurface conditions may vary between exploration locations. Such changes in subsurface conditions may not be apparent until construction, and if they change significantly from those observed during exploration, then accordingly, construction timing, plans, and costs may change. 5.2 Subsurface Water At the time of exploration, we did not observed groundwater within test pits to maximum depths of 7 to 13 feet below existing ground. Groundwater in the area is typically influenced by local irrigation and nearby canals, drains, and laterals. Groundwater may also be influenced by precipitation, on-site construction, and development to adjacent sites. Subsurface water will fluctuate throughout the different seasons of the year, but will most likely be affected during seasonal snow melt and irrigation seasons (March to October). GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 4 Meridian, Idaho We installed slotted PVC pipes within 10 test pits throughout the site for future groundwater monitoring. ALLWEST will begin monthly groundwater monitoring in March 2022 to help establish seasonal high groundwater elevations throughout the site. 6.0 LABORATORY TESTING We performed laboratory testing to supplement field classifications and to assess some of the soil engineering properties and parameters. The laboratory tests conducted included moisture content (ASTM D 2216), gradation (ASTM D 1140), Atterberg limits (ASTM D 4318), and California bearing ratio (CBR) (ASTM D 1883). Laboratory test results are summarized in Appendix C and are also presented on test pit logs in Appendix B, where applicable. 7.0 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 adhered to. The following recommendations are presented to assist with 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 scope of construction changes, or if conditions are encountered during construction that differ from those described herein, we should be notified so we can review our recommendations and provide revisions, if necessary. Foundation-related recommendations are not provided as part of this evaluation. 7.1 Grading and Drainage We did not review final grading plans for this development, but we anticipate site grading will consist of cuts and fills up to 2 feet or less. We should be notified if actual site grading varies significantly from this stated information, as it may affect our recommendations. Final site grading should be such that surfaces slope down and drain away from any development areas. 7.2 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 6 inches of site stripping will be required for most of the site to remove surficial vegetation and roots, with some areas up to 12 inches. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 5 Meridian, Idaho • 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 roots 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. • Where existing structures, outbuildings, and infrastructure are located that will be demolished as part of this development, complete over-excavation down to native soils is required. This includes any existing drain field areas or other previously placed fill areas. Depths and lateral limits of existing infrastructure will not fully be known until construction. As such, the earthwork contractor should have contingencies in place to ensure these areas are fully over-excavated within future development areas. • Where existing irrigation ditches/laterals are located within proposed development areas, complete over-excavation of organic-type, loose, and soft/wet soils down to firm or medium dense native soils is required. Depths and lateral limits of organic- type, loose, and soft/wet soils associated with existing irrigation ditches/laterals will not fully be known until construction. As such, the earthwork contractor should have contingencies in place to ensure these areas are fully over-excavated within future development areas. • Loose test pit backfill will settle with time, so where any test pits are located below proposed structures or any development areas, loose test pit backfill soil must 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 can achieve the required compaction criteria as required in section 7.6 Fill Placement and Compaction. Test pit locations that were observed by ALLWEST are identified in the field with white PVC pipes and/or stakes with white flagging. Approximate test pit locations are shown on Figure A-2: Exploration Location Plan. 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, exposed subgrades should be proof-rolled with a minimum of a 5-ton vibratory roller, with loaded dump trucks, with loaded front-end loaders, or with a vibratory hoe-pack to confirm subgrade stability. This will also assist in identifying any soft subgrade areas. If subgrades are observed to significantly deflect or pump, the subgrade soils should be over-excavated to firm or medium dense native soils and replaced with properly compacted fills. As an alternative, subgrades may be stabilized as recommended in section 7.3 Subgrade Stabilization prior to fill placement. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 6 Meridian, Idaho 7.3 Subgrade Stabilization If the subgrade soils are observed to pump or deflect significantly during grading, the subgrades should be stabilized prior to fill placement. 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 must be approved by the geotechnical engineer prior to use on site. The following recommendations are provided for subgrade stabilization using reinforcement materials. • Reinforcement materials should be placed on a properly prepared non-disturbed subgrade with smooth surface. Loose and disturbed soil should be removed prior to placement of reinforcement materials. • If geogrid reinforcement is used, a minimum weight 4-ounce, non-woven filter fabric should be placed on the properly prepared subgrade. The geogrid reinforcement should be placed directly on top of the filter fabric. The filter fabric and/or 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 the reinforcement materials. 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 material before operating construction equipment on the fill. Low pressure, track-mounted equipment should be used to place 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 filter fabric and/or reinforcement material, and granular structural fill is considered the "bridge" section over soft subgrades. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 7 Meridian, Idaho • After the "bridge" section has been placed, the remaining fill material above the "bridge" section should be compacted to structural fill criteria in section 7.6 Fill Placement and Compaction, utilizing vibratory compaction methods. • Vibration 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 must be attempted again with a thicker "bridge" section. The geotechnical engineer or a representative of the geotechnical engineer must be on- site during subgrade stabilization to verify our recommendations are followed, and to provide additional recommendations, as needed. 7.4 Excavation Excavation of on-site soil can be accomplished with typical excavation equipment. We recommend excavations greater than 4 feet deep be sloped no steeper than 1.5H:1V (horizontal to vertical). Alternatively, deeper excavations may be shored or braced in accordance with Occupational Safety and Health Administration (OSHA) specifications and local codes. Regarding trench wall support, the site soil is considered Type C soil according to OSHA guidelines. Ultimately, the contractor is responsible for site safety, excavation configurations, and following OSHA guidelines. 7.5 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, meet the criteria below, and 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 Retained on /4-inch sieve < 30o ; Liquid limit < 50/o Maximum size <_ 6 inches; Granular Structural Fill, Retained on %-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 %-inch sieve < 30%; Passing No. 200 sieve <_ 100 ; Non-plastic Alternatively, meet ISPWC section 305 (Type I) GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 8 Meridian, Idaho 7.6 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 typical rubber- tire and steel-drum compaction equipment. Lift thicknesses 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 following percentages of the maximum dry density as determined by ASTM D 1557 (modified Proctor). For 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). Fill Area Compaction Sub rade' Proof-roll' Site Grading Fill / Granular Structural Fill 95 Granular Subbase/ Crushed Base Course 952 Utility Trench Backfill 922 'Subgrade stability must 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). 7.7 Utility Trenches Support soils for underground utilities will most likely consist of lean clay with sand, sandy silt, sand, and gravel soils. These 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 or are saturated at the time of construction, we should be notified to observe these soils and provide additional recommendations, as necessary. We strongly recommend backfilling trench excavations with fill soils which meet the criteria in section 7.5 Materials, as on-site fine-grained soils (silts and clays) may be difficult to moisture-condition and compact in utility trenches. 7.8 Wet Weather Construction We recommend earthwork for this 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. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 9 Meridian, Idaho 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. 7.9 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 observed. 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 must 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. Any frozen soils should be removed prior to additional 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. 7.10 Stormwater Disposal During our field investigation we performed field seepage testing in test pits TP-2, -5, -7, -8, and -11 within poorly-graded gravel with sand and cobble soils. We obtained field- measured seepage rates of greater than 30 inches per hour (in/hr) within poorly-graded gravel with sand and cobbles. Due to poor and inconsistent seepage, we do not recommend stormwater disposal be accomplished within clayey soils or soils with cementation/induration. Refer to test pit logs in Appendix B to verify depths and contacts of cemented/indurated soils which are not suitable for stormwater disposal. We recommend stormwater disposal occur within the poorly-graded gravel with sand and cobble soils observed during our field exploration. The following allowable seepage rate should be utilized for on-site civil stormwater disposal design. • Poorly-Graded Gravel with Sand and Cobbles ........................... 8 in/hr GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 10 Meridian, Idaho Stormwater disposal facilities should be constructed a minimum of 1 foot into the receiving soil. Stormwater disposal facility drain rock and filter sand materials should maintain a separation/filter fabric between native fine-grained soils and drain rock/filter sand to help prevent fine-soil migration into drainable/filtering media, as required by civil design. ALLWEST should observe stormwater disposal facility subgrades to establish if the suitable receiving soil is encountered (based on civil design depths), to confirm the allowable seepage rate, and to ensure the separation/filter fabric has been properly installed (as required by civil design). The proper separation from bottom of stormwater disposal facilities and seasonal high groundwater should be maintained. As such, seasonal high groundwater should be confirmed via groundwater monitoring throughout seasonal snow melt and irrigation seasons, to assist civil stormwater design. We installed slotted PVC pipes within 10 test pits throughout the site for future groundwater monitoring. ALLWEST will begin monthly groundwater monitoring in March 2022 to help establish seasonal high groundwater elevations throughout the site. 7.11 Asphalt Pavements Prior to pavement section construction, the pavement subgrade should be proof-rolled as recommended in section 7.2 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, it is anticipated that majority of roadway subgrade areas will consist of lean clays with sand. We performed CBR testing on a lean clay with sand soil for pavement section design, where we obtained a CBR of 6, which is approximately equivalent to an R-value of 14. The following flexible asphalt pavement section design is provided adhering to the Idaho Transportation Department (ITD), which utilizes the AASHTO pavement design methodology. 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, and for parking and access drives. Asphalt Crushed Granular Pavement Application Concrete Base Course Subbase inches (inches) inches Local Roadway, Access Drives, Parking 2.5 4 11 Collector Roadway 3 6 14 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 GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Geotechnical Evaluation ALLWEST Project No. 521-497G Modern Craftsman Eagle Road Development Page 11 Meridian, Idaho surfaces should slope at no less than 2% to help reduce the potential for surface water infiltration into the underlying pavement sections and subgrade soils. If the overall site is relatively flat, then finished asphalt surfaces should slope away at no less than 2% from the crown of the roadways. Crack maintenance on pavements should be performed at a minimum of every 3 years, or when cracking is evident. Crack sealing will help reduce surface water infiltration into the supporting soils. 8.0 ADDITIONAL RECOMMENDED SERVICES To maintain continuity and efficiency, we recommend ALLWEST be retained to provide observations and testing throughout construction. As an independent testing company, ALLWEST can document the recommendations included in this report are properly implemented, 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 of tree root systems, demolished structures/infrastructure, and organic-type, loose, and soft/wet soils associated with ditches/laterals; test pit remediation; and other over-excavations and backfills. • Observe subgrade proof-rolling and approve subgrades prior to fill construction, materials placement, or roadway section construction. • Observe removal of disturbed soil and subgrade stabilization, if required. • Observe stormwater disposal facility subgrades, confirm seepage rates by performing large-scale seepage testing, and observe overall construction. • Conduct compaction testing of fill soils for general site grading, utility backfills, and pavement subsections. • 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. 9.0 EVALUATION LIMITATIONS This report has been prepared to assist planning, design, and construction of the proposed Modern Craftsman Eagle Road Development in Meridian, Idaho. Our services consist of professional opinions and conclusions made in accordance with generally accepted geotechnical engineering principles and practices in our local area at the time this report was prepared. This acknowledgement is in lieu of all warranties either expressed or implied. GEOTECHNICAL I ENVIRONMENTAL ALLWESTMATERIALS TESTING I SPECIAL INSPECTION AN EMPLOYEE-OWNED COMPANY Appendix A A-1 : Site Vicinity Map A-2: Exploration Location Plan ALLWEST F.I�I,fiL '+}hNJs is ti/L'�C.?5Q"F•.•.: • r r S1iE lr•R - _ �... `'Y _ �•�. �}. ya _ - as "+'•.� s•: Z` F.£ •'r"�ti �f'a�IINIfYI! s. ;� ��r, �" f�. ;, 'f ^ii:� ,ss^��'''- _ - 1#... i+•ti - - Y :i��^, �,.�•- it" ,r��1 '� Al :. --} :`��'[ -I - � �{,9 ,.,'�' Yam'. .. ""' �s�■ �7�I'F y ��L�� '''•r"� � ��' 1[ :1 .,Mtltnl _ .fir � '�. �_r{�,��ar � -lei 11� 1 ■ � _._.�'� •,�e�� Im _ ..� �::��.- G •rk ��=�� .ti-car_-.�-.��ae:i i'i.—` '�� y `i•r .•� ..i:��: AAPUErGR ME(-URANKL;{fr .`y� I 7 y y:r i+ z •'r hlCAl S• •As QIJN.LY Ab G c . ;,.. •3 •I 71 .ri• Il-RI ':Ti rp P, ilk ' L. TA . 1 EVALUATION CRAFTSMANMODERN EAGLE MERIDIAN, . . • -� II BAILEYCLIENT: Si •SiPROJECT • I• DATE: MARCH 2022 TP-1 TP-2 * TP-* Ir 0 I � .w,cr ,n • ,r ua as x� �, � a '•cd r» � x j w� ,ka„ .aw; s`r` . �,. e •aw, •ee rx a e, •c•,r : I C�D J I ,fie �•� w •K�• i $� y •V: $� $ •��• .roses K. nc•.o. h TP 4; —_- _-- TW*I TP-6 ------------ --------------------------L--------- -- r r r I a 4 I�`�� x S� 4n ` p q• -; i I �' o t 4 .�•� r ;.� C t I,I i II��I1-,i-�{-y�Jr-r-r�� l - - -- - .a. ..• TP-9 Li IkAl 5T.IP-8p—R- F------_---- —i-- --- --- I ha r 3 I i �c' I ,� ■ i.I TP-10 Boundary " .- N Legend 0 Approximate location of test pit observed by ALLWEST. { * Indicates PVC pipe installed in test pit. Reference:Conceptual Plan for Modern Craftsman Eagle Road 0 120' 240' prepared by Bailey Engineering,Inc.dated September 5, 2021 ■ 'y7 FIGURE A-2:EXPLORATION LOCATION PLAN GEOTECHNICAL EVALUATION ALLWESTMODERN CRAFTSMAN EAGLE ROAD DEVELOPMENT MERIDIAN, IDAHO 255 N.LINDER ROAD,SUITE 100 CLIENT: BAILEY ENGINEERING MERIDIAN IDAHO,83642 PHONE:(208)895-7898 FAX:(208)898-3959 PROJECT NO.:521-497G DATE: MARCH 2O22 Appendix B Test Pit Logs Unified Soil Classification System (USCS) ALLWEST ALLWEST DATE STARTED: 11/10/2021 TP - 1 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'45.8688"(43.579408°) 0 LONGITUDE(DEGREES):W-116°21'12.7512" (-116.353542°) � U (n TOTAL DEPTH: 11' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 12 inches CL 1 Poorly-Graded SAND;light brown,dense,moist 2- 3- 4— ...weak to moderate cementation observed throughout soil profile SP 5- 6— Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, subrounded up to 6 inches maximum dimension ° 0 O 8 0� 0 O o� 9 GP 0 O o� 1 O 0 O 1 Test pit terminated at 11 feet due to caving. Slotted PVC pipe installed to 11 feet. 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 2 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'45.8796"(43.579411°) 0 LONGITUDE(DEGREES):W-116°21'9.2448" (-116.352568°) � U (n TOTAL DEPTH: 10' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 CL inches 1 Poorly-Graded SAND with Silt;light brown,dense,moist 2 sPSM 3 Bag 3'-3.5' Passing No.200 sieve=8% Moisture content=25% Poorly-Graded GRAVEL with Silt and Sand;light brown,dense,moist 0 4 0 GP Gm ...moderate cementation observed throughout soil profile 0 O 5 0 Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, subrounded up to 5 inches maximum dimension ° Field seepage test performed at 6 feet. 6 IR Q Field seepage rate=>30 in/hr. o� O 7 Q o� GP o Q 8 0� O Q o� 9 0 Q o� O 1 Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed to 10 feet. 1 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 3 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'45.6816"(43.579356°) 0 LONGITUDE(DEGREES):W-116°21'5.6088" (-116.351558°) � U (n TOTAL DEPTH:7' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 12 inches 1 CL 2 3 Poorly-Graded SAND;light brown,medium dense,moist sP ...weak cementation observed throughout soil profile 4— Poorly-Graded GRAVEL with Sand,Cobbles,and Boulders;tan, dense to very dense,moist,subrounded up to 18 inches maximum ° 5 dimension o O GP ° 0 6 O 0 O 7 Test pit terminated at 7 feet due to excavator refusal on very dense cobbles and boulders. Slotted PVC pipe installed to 7 feet. 8 9 1 1 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 4 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'42.3912"(43.578442°) 0 LONGITUDE(DEGREES):W-116°21'12.6648" (-116.353518°) � U (n TOTAL DEPTH: 12' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 3 inches CL 1 Poorly-Graded SAND;light brown,medium dense,moist 2 3 sP ...moderate to strong cementation observed throughout soil profile 4 5 Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense to medium dense,moist,subrounded up to 6 inches maximum ° dimension o ...weak cementation observed from 5 to 6 feet O 6 ------------------------------------------------- o� O O o� 7 0 O o� 8 O o� GP 0 O 9 0� 0 O 1 O 1 � O 0 O 12 Test pit terminated at 12 feet. Slotted PVC pipe installed to 12 feet. 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 5 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'42.582"(43.578495°) 0 LONGITUDE(DEGREES):W-116°21'9.3744" (-116.352604°) � U TOTAL DEPTH: 10' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 inches CL 1 Poorly-Graded SAND;light brown,medium dense to dense,moist 2- 3- 4— sP ...weak to moderate cementation observed throughout soil profile 5- 6— Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, subrounded up to 5 inches maximum dimension Field seepage test performed at 7 feet. 7 Field seepage rate=>30 in/hr. O 0 8 O GP ° 0 O 9 0 Cy O 1 Test pit terminated at 10 feet due to caving. Slotted PVC pipe installed to 10 feet. 1 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 6 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'42.4632"(43.578462°) 0 LONGITUDE(DEGREES):W-116°21'5.4108" (-116.351503°) � U (n TOTAL DEPTH:9' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 inches 1 CL 2 Poorly-Graded SAND;light brown,dense,moist SP 3— Poorly-Graded GRAVEL with Sand and Cobbles;tan,very dense to dense,moist,subrounded up to 4 inches maximum dimension ° 4 oO o� ...moderate to strong cementation observed from 3.5 to 6 feet o 5 O o� O Q g ------------------------------------------------- °� GP --- 0 o� 7 0 Q o� 8 O o� O Q 9 Test pit terminated at 9 feet due to caving. Slotted PVC pipe installed to 9 feet. 1 1 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 7 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'40.2348"(43.577843°) 0 LONGITUDE(DEGREES):W-116°21'12.384" (-116.35344°) � U (n TOTAL DEPTH: 11.5' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 inches Passing No.200 sieve=75% 1 Bulk 0.5'-1.5' LL=42,PL=20,PI=22 cL CBR=6.0 2 Poorly-Graded SAND;light brown,dense to very dense,moist 3 4 sP ...moderate to strong cementation observed throughout soil profile 5 6 7 Sandy SILT;brown to dark brown,dense,moist ML ...moderate induration observed throughout soil profile 8 Field seepage test performed at 8.5 feet. Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, Field seepage rate=>30 in/hr. subrounded up to 4 inches maximum dimension o Bag 8.5'-9' Passing No.200 sieve=2% 9 o Moisture content=4% O o� 1 GP O o� O O 1 0C 0 Test pit terminated at 11.5 feet due to caving. Slotted PVC pipe installed to 11.5 feet. 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 8 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'40.1844"(43.577829°) 0 LONGITUDE(DEGREES):W-116°21'9.342" (-116.352595°) � U (n TOTAL DEPTH: 10.5' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 CL inches 1 Poorly-Graded SAND;light brown,dense,moist 2 3 sP ...moderate to strong cementation observed throughout soil profile 4 5 Poorly-Graded GRAVEL with Sand and Cobbles;tan,very dense to dense,moist,subrounded up to 5 inches maximum dimension ° 0 ...weak cementation observed from 5 to 6.5 feet 6 ------------------------------------------------- O 7 0 Field seepage test performed at 7.5 feet. GP ° Field seepage rate=>30 in/hr. 8 O o� O O 9 0� 0 O 1 O Test pit terminated at 10.5 feet due to caving. Slotted PVC pipe installed to 10.5 feet. 1 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 9 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'40.5084"(43.577919°) 0 LONGITUDE(DEGREES):W-116°21'5.3748" (-116.351493°) � U (n TOTAL DEPTH: 13' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 inches 1 CL 2 Poorly-Graded SAND;light brown,dense,moist 3 sP ...moderate to strong cementation observed throughout soil profile 4 5 Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense to very dense,moist,subrounded up to 4 inches maximum dimension ° 0 Q 6 0 Q o� o� O 8 ...weak to moderate cementation observed from 7 to 9 feet o� O Q 9 Sandy SILT;brown to dark brown,dense,moist ML weak induration observed throughout soil profile 1 Poorly-Graded SAND with Silt and Gravel;light brown,dense,moist sPSM 1 Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, subrounded up to 6 inches maximum dimension ° 0 12 GP ° 0 o Q 1 Test pit terminated at 13 feet. Slotted PVC pipe installed to 13 feet. 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 10 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'38.3232"(43.577312°) 0 LONGITUDE(DEGREES):W-116°21'11.574" (-116.353215°) � U (n TOTAL DEPTH: 13' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 inches 1 2— CL 3 4 Poorly-Graded SAND;light brown,dense,moist Bag 4.5'-5' Passing No.200 sieve=4% Moisture content=28% 5 6 SP ...moderate to strong cementation observed throughout soil profile 7 8 Sandy SILT;brown to dark brown,dense,moist 9 ML ...moderate induration observed throughout soil profile Passing No.200 sieve=61 Bag 9'-9.5' Moisture content=21% LL=NV,PL=NP,PI=NP 1 Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, subrounded up to 6 inches maximum dimension ° 0 Q 1 ° Bag 11'-11.5' Passing No.200 sieve=3% o GP Moisture content=4/°Q o Q 12 0 o Q O 1 Test pit terminated at 13 feet. 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t AFTER EXCAVATING Sheet 1 of 1 ALLWEST DATE STARTED: 11/10/2021 TP - 11 DATE FINISHED: 11/10/2021 EXCAVATOR: CASE 580C MERIDIAN,IDAHO OPERATOR: Steve Just GEOTECHNICAL SECTION COMPANY: Just Dig'It Exc. EXCAVATION METHOD: 2-ft wide test pit LOGGER:Kevin Dyekman TEST PIT LOG WEATHER: Sunny PROJECT:521-497G NOTES: See Figure A-2 in Appendix A for approximate test pit location. Modern Craftsman-Eagle Road LATITUDE(DEGREES):N 43°34'39.1944"(43.577554°) 0 LONGITUDE(DEGREES):W-116°21'6.2928" (-116.351748°) � U (n TOTAL DEPTH:8' = SAMPLE W Q DESCRIPTION � NOTES Lean CLAY with Sand(Native);brown,stiff,moist Significant roots and vegetation observed to 6 inches Passing No.200 sieve=83% CL Bag 0.5'-1' Moisture content=19% 1 LL=41,PL=23,PI=18 Poorly-Graded SAND;light brown,dense,moist 2 sP ...weak cementation observed throughout soil profile 3 4 Poorly-Graded SAND with Silt and Gravel;light brown,dense,moist sPSM 5 Poorly-Graded GRAVEL with Sand and Cobbles;tan,dense,moist, subrounded up to 6 inches maximum dimension ° 0 6 Field seepage test performed at 6 feet. Field seepage rate=>30 in/hr. GP Q o� 7 0 Q o� O 8 Test pit terminated at 8 feet due to caving. Slotted PVC pipe installed to 8 feet. 9 1 1 12 1 14 WATER LEVELS 2 WHILE EXCAVATING Y AT COMPLETION t 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. Silty Sand, SANDS L SM Sand-Silt Mixtures. WITH FINES Sc Clayey Sand, 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 ALLWEST Summary of Laboratory Test Results Moisture Gradation Atterberg Limits Test Pit Depth Liquid Plasticity CBR Sample Classification No. (Feet) Content Gravel Sand Silt/Clay Limit Index % USCS TP-2 3 - 3.5 25 8 Poorly-Graded SAND with Silt(SP-SM) TP-7 0.5- 1.5 - 75 42 22 6.0 Lean CLAY with Sand CL TP-7 8.5- 9 4 2 Poorly-Graded GRAVEL with Sand and Cobbles (GP) TP-10 4.5- 5 28 4 Poorly-Graded SAND SP TP-10 9 - 9.5 21 61 NV NP Sandy SILT (ML) TP-10 11 - 11.5 4 3 Poorly-Graded GRAVEL with Sand and Cobbles GP TP-11 0.5- 1 19 83 41 18 Lean CLAY with Sand (CL) NV=No Value NP=Non Plastic Table C-1 255 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 �0 ' G 40 U C � X W N— Z_ � v 30 c F- LU C/) ' Q i J / d ` - a: 20 A 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 • Lean Clay with sand 42 20 22 75% CL c■ Sandy Silt NV NP NP 61% ML CD♦ Lean Clay with sand 41 23 18 83% CL X m m U 7 O ` Project No. 521-497G Client: Bailey Engineering,Inc. Remarks: aD Project: Modern Craftsman Eagle Road c *Location: TP-7 Depth: 0.5-1.5 ■Location: TP-10 Depth: 9-9.5 ALocation: TP-11 Depth: 0.5-1 0 cn ALLWEST Figure C-1 Tested By: C. Downes Checked By:J.Varozza California Bearing Ratio ASTM D1883 Project: Modern Craftsman Eagle Road Project No.: 521-497G Client: Bailey Engineering, Inc. Location: TP-7 @ 0.5 - 1.5 ft Date Tested: 12/7/21 Compaction Method: ASTM D1557 Tested By: C. Downes Classification: Lean Clay with sand (CL) 120 105 90 VI 75 c 0 N 60 ° PSI @ 0.1 inch penetration= 60 a n 45 30 15 0 0 0.1 0.2 0.3 0.4 0.5 Penetration(inches) CBR @ 0.1 Inch Penetration: 6.0 Maximum Dry Unit Weight(pcf): 106.7 Swell (%): 3.5 Optimum Water Content(%): 15.6 Dry Unit Weight Before Soak (pcf): 96.6 Remold of Max. Dry Unt Wgt (%): 91 Water Content Before Soak(%): 16.3 Water Content After Soak, Top 1 Inch (%): 33.0 Surcharge (psf): 50 Immersion Period (hrs): 96 Reviewed By: James Varozza Figure: C-2 ►LLIET 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.