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Home My WebLink AboutO'Reilly Auto Parts Store - Proposed - Geotechnical Engineering ReportGeotechnical Engineering Report Proposed O'Reilly Auto Parts Store 3377 North Ten Mile Road Meridian, Idaho March 21, 2012 Terracon Project No. 62125009 Prepared for: O'Reilly Automotive Stores, Inc. Springfield, Missouri Prepared by: Terracon Consultants, Inc. Boise, Idaho March 21. 2012 O'Reilly Automotive Stores, Inc. 233 South Patterson Avenue Springfield, Missouri 65802 Attn: Mr. Curt McNay, Survey/Geotech Coordinator P: [417] 874-7312 E: cmcnay@oreillyauto.com Re: Geotechnical Engineering Report Proposed O'Reilly Auto Parts Store 3377 North Ten Mile Road Meridian, Idaho Terracon Project No. 62125009 Dear Mr. McNay: 1 rarracon Terracon Consultants, Inc. (Terracon) has completed the geotechnical engineering services for the above referenced project. These services were performed in general accordance with O'Reilly Auto Parts — Work Order Authorization Number MD5 dated 03106/2012. This geotechnical engineering report presents the results of the subsurface exploration and provides geotechnical recommendations concerning earthwork and the design and construction of foundations, floor slabs, and pavements for the proposed project. We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report, or if we may be of further service, please contact us. Sincerely, Terracon 12134 Ryan J. Olsen, P. Geotechnical Department Manager Attachments RJO:aa\62125009_Geotech_Eng_Rpt_Meridian_I D_O'Reilly.doc tathe�w B. Fielding,P.E. Boise Office Manager Copies to: Addressee (1 Electronic) Melanie Robertson (1 Electronic- mrobertson@oreillyauto.com) Terracon Consultants, Inc. 11849 West Executive Drive, Suite G Boise, Idaho 83713 P [208] 323 9520 F [208] 323 9592 lerracon.com Geotechnical Engineering Report Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 TABLE OF CONTENTS lrerracon Page No EXECUTIVE SUMMARY.............................................................................................................iii 1.0 INTRODUCTION...............................................................................................................1 2.0 PROJECT INFORMATION...............................................................................................1 2.1 Project Description................................................................................................1 2.2 Site Location and Description................................................................................2 3.0 SUBSURFACE CONDITIONS..........................................................................................2 3.1 Typical Subsurface Profile.....................................................................................2 3.2 Groundwater..........................................................................................................3 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION.......................................3 4.1 Geotechnical Considerations.................................................................................3 4.2 Earthwork... .................................. ........................................................................ 4 4.2.1 Site Clearing and Subgrade Preparation...................................................4 4.2.2 Fill Materials and Placement......................................................................4 4.2.3 Grading and Drainage...............................................................................5 4.2.4 Earthwork Construction Considerations....................................................5 4.3 Foundations...........................................................................................................6 4.3.1 Spread Footing Recommendations...........................................................6 4.3.2 Foundation Construction Considerations...................................................6 4.4 Seismic Considerations.........................................................................................6 4.5 Floor Slabs............................................................................................................7 4.6 Pavements............................................................................................................7 4.6.1 Asphalt Pavement Sections.......................................................................7 4.6.2 Portland Cement Concrete Pavement Sections........................................8 4.6.3 Pavement Design Considerations.............................................................9 4.6.4 Pavement Construction Considerations..................................................10 5.0 GENERAL COMMENTS.................................................................................................10 APPENDIX A — FIELD EXPLORATION Exhibit A-1 Vicinity Map Exhibit A-2 Boring Location Plan Exhibit A-3 Field Exploration Description Boring Logs APPENDIX B — LABORATORY TESTING Exhibit B-1 Laboratory Test Description APPENDIX C — SUPPORTING DOCUMENTS Exhibit C-1 General Notes Exhibit C-2 Unified Soil Classification System Responsive ■ Resourceful ■ Reliable Geotechnical Engineering Report l�err�con Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 EXECUTIVE SUMMARY A geotechnical exploration has been performed for the proposed O'Reilly Auto Parts Store to be located at 3377 North Ten Mile Road in Meridian, Idaho. Field explorations included drilling six test borings within the proposed project area. Based on the information obtained from our subsurface exploration, the site can be developed for the proposed project. The following geotechnical considerations were identified: ■ Existing fill materials were found in the borings at the site at depths ranging from about '/2 to 2 feet below the existing ground surface. Undocumented fill soils are not suitable for support of the proposed structure or pavement and should be completely removed from building and pavement areas. ■ The proposed structure can be supported on shallow spread footings bearing on undisturbed native soils or on compacted Structural Fill that is supported directly on the native soils. ■ Based on the 2009 International Building Code, the seismic site classification for this site is D. ■ Floor slabs should be supported on a minimum of 4 inches of crushed aggregate base overlying the native soils or Structural Fill that extends to the native soil, This summary should be used in conjunction with the entire report for design 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. The General Comments Section should be read for an understanding of the report limitations. Responsive ■ Resourceful ■ Reliable GEOTECHNICAL ENGINEERING REPORT PROPOSED O'REILLY AUTO PARTS STORE 3377 NORTH TEN MILE ROAD MERIDIAN, IDAHO Terracon Project No. 62125009 March 21, 2012 1.0 INTRODUCTION This report presents the results of geotechnical engineering services performed for the proposed O'Reilly Auto Parts Store to be constructed in Meridian, Idaho. Our services consisted of drilling borings to determine subsurface conditions, performing laboratory testing on representative soil samples, performing engineering analyses of the subsurface soils, and preparing this report. The purpose of these services is to provide information and/or geotechnical engineering recommendations relative to: ■ subsurface soil conditions ■ groundwater conditions at the time of ■ earthwork the field exploration ■ seismic considerations ■ foundation design and construction ■ pavement design and construction ■ floor slab design and construction 2.0 PROJECT INFORMATION 2.1 Project Description Item Description' Site layout i Refer to the Boring Location Plan (Appendix A). Single -story retail building with a footprint of about 80 feet by 85 Structure feet. Building construction Masonry walls with a slab -on -grade floor system. Columns: 30 kips Maximum building loads Walls: 1 kips per linear foot Floors: 125 pounds per square foot Grading is anticipated to be relatively minor and generally limited Grading to providing a level construction area. We have assumed maximum cuts and fills will be approximately 2 feet or less. Retaining & basement walls None Responsive ■ Resourceful ■ Reliable 1 Geotechnical Engineering Report Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 Item Description' lrerracon Pavement design criteria Flexible Pavement: 14,000 18 -kip ESALs (flexible) (assumed) Rigid Pavement: 20,000 18 -kip ESALs (rigid) 1. In the event these details are inconsistent with final design criteria, we should be contacted so that we may update our recommendations as needed. 2.2 Site Location and Description Item Location Existing site features Surrounding developments Description The project site is located at 3377 North Ten Mile Road in Meridian, Idaho. See project Vicinity Map in Appendix A. The project site is currently vacant. The site has previously been rough graded. A landscaped berm and a concrete sidewalk are on the east side of the project site adjacent to Ten Mile Road. North. South, and West: Vacant parcels that have been rough graded for future development. East: Ten Mile Road followed by a residential subdivision. Current ground cover Weeds and grasses Based on the relative elevations at the boring locations, there is Existing topography approximately 1% feet of relief across the proposed building area and approximately 2% feet across the site. 3.0 SUBSURFACE CONDITIONS A description of our field exploration is presented in Appendix A. Laboratory tests were conducted on selected soil samples obtained during our exploration. A description of the laboratory testing is presented in Appendix B. 3.1 Typical Subsurface Profile Specific conditions encountered at each boring location are indicated on the individual boring logs, which are presented in Appendix A. Stratification boundaries on the logs represent the approximate locations of changes in soil types; in-situ, the transition between materials may be gradual. Based on our borings and laboratory testing, generalized soil conditions for the project site are presented in the following table. Description Approximate Depth' to Material Encountered Consistency/Density Bottom of Stratum Fill composed of variable Stratum 1 %to 2 feet mixtures of silt, clay, sand, and gravel. Responsive ■ Resourceful ■ Reliable 2 Geotechnical Engineering Report l��rracon Proposed O'Reilly Auto Parts Store iii Meridian, Idaho March 21, 2012 in Terracon Project No. 62125009 1. Depth below wasting ground surface, as encountered in our borings. 3.2 Groundwater The borings were monitored during drilling for the presence and level of groundwater. Groundwater was encountered within the borings at the time of our exploration at depths ranging from about 7'/ to 8'/ feet below the existing ground surface. Fluctuations of the depth to groundwater may occur due to seasonal variations in the amount of irrigation, rainfall, runoff, and other factors not evident at the time the borings were performed. Evaluation of these factors is beyond the scope of this exploration. 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION 4.1 Geotechnical Considerations Based on the materials encountered in the borings drilled at this site, it is our opinion that the site is suitable for support for the proposed structure, provided the recommendations included in this report are incorporated into project design and construction. A primary geotechnical consideration identified during the exploration is summarized below. ■ As discussed in Section 3.1, existing fill materials were found in the borings at depths ranging from about '/ to 2 feet below the existing ground surface. Undocumented fill soils are not suitable for support of the proposed structure or pavement and should be completely removed from building and pavement areas. Specific conclusions and recommendations regarding this geotechnical consideration, as well as other geotechnical aspects of design and construction are presented in the following sections. The recommendations contained in this report are based upon the results of field and laboratory testing, engineering analyses, and our current understanding of the proposed project. Responsive ■ Resourceful ■ Reliable 3 Approximate Depth' to Description Material Encountered Consistency/Density Bottom of Stratum Lean clay to silty clay with varying amounts of sand and Stratum 2 2'/ to 7'/ feet interbedded layers of silt to silty Soft to hard sand. In boring B-6 a sandy silt layer was encountered that was moderatt� cemented. 13'/ feet to the maximum Stratum 3 depth explored of 16'/ Gravel with silt and sand to Medium dense to very gravel with sand dense feet. Extended to the Sand to sand with silt. This Stratum 4 maximum depth explored of 161/2 feet stratum was only encountered Medium dense to dense (where encountered) in borings B-1 and B-2. 1. Depth below wasting ground surface, as encountered in our borings. 3.2 Groundwater The borings were monitored during drilling for the presence and level of groundwater. Groundwater was encountered within the borings at the time of our exploration at depths ranging from about 7'/ to 8'/ feet below the existing ground surface. Fluctuations of the depth to groundwater may occur due to seasonal variations in the amount of irrigation, rainfall, runoff, and other factors not evident at the time the borings were performed. Evaluation of these factors is beyond the scope of this exploration. 4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION 4.1 Geotechnical Considerations Based on the materials encountered in the borings drilled at this site, it is our opinion that the site is suitable for support for the proposed structure, provided the recommendations included in this report are incorporated into project design and construction. A primary geotechnical consideration identified during the exploration is summarized below. ■ As discussed in Section 3.1, existing fill materials were found in the borings at depths ranging from about '/ to 2 feet below the existing ground surface. Undocumented fill soils are not suitable for support of the proposed structure or pavement and should be completely removed from building and pavement areas. Specific conclusions and recommendations regarding this geotechnical consideration, as well as other geotechnical aspects of design and construction are presented in the following sections. The recommendations contained in this report are based upon the results of field and laboratory testing, engineering analyses, and our current understanding of the proposed project. Responsive ■ Resourceful ■ Reliable 3 Geotechnical Engineering Report 11'�rracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 4.2 Earthwork The recommendations presented in this report for design and construction of foundations, slabs, and pavements are contingent upon the successful performance of the tasks related to the earthwork recommendations outlined in this section. Earthwork on the project should be observed and evaluated by Terracon. Monitoring of earthwork should include observation and testing of site clearing and subgrade preparation, placement of Structural Fill, foundation construction, and other geotechnical conditions exposed during the construction of the project. 4.2.1 Site Clearing and Subgrade Preparation Prior to construction, deleterious materials such as undocumented fill, vegetation, root systems, topsoil, debris, manmade structures/utilities, and soft, frozen, disturbed, or otherwise unsuitable materials should be completely removed from the proposed building and pavement areas. As previously discussed, fill soils were encountered in all of the borings drilled to depths ranging from about '% to 2 feet below the existing site grade. Care should be taken to completely remove these fill soils from building and parking areas. Exposed surfaces should be free of mounds and depressions that could prevent uniform compaction. After removal of the materials described above is complete, the top 8 inches of the exposed native soils in the areas to be occupied by the building and pavements should be scarified, moisture conditioned to near optimum moisture content, and compacted to the requirements outlined in Section 4.2.2 of this report. 4.2.2 Fill Materials and Placement Material requirements for soils used as Structural Fill within the proposed building area (and extending at least 5 feet beyond the perimeter of the structure) are outlined in the table below. Building Area 3 -inch minus gravel and sand meeting the requirements of the Idaho Standards for Public Works Construction (ISPWC) Section 801, Uncrushed Aggregates. Within proposed parking areas and other locations outside of the building, materials used as Structural Fill should meet the requirements presented below. Parking and Other Areas Outside the Building Percent Passing Sieve Size 6 -inch No. 4 100 15-100 Responsive ■ Resourceful ■ Reliable 4 Geotechnical Engineering Report l��rracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 Parking and Other Areas Outside the Building Sieve Size Percent Passing No. 200 Less than 25 Liquid limit should be less than 30 percent, the plasticity index should be less than 10 percent, and the organic content should be less than 3 percent. Fill should be placed in maximum 8 -inch -thick, loose lifts, adjusted to near optimum moisture content, and compacted to the minimum percentages of either maximum dry density or relative density shown in the following table, whichever is appropriate for the material being used. Each lift of fill should be tested at various locations within the structures footprint and parking/drive areas to verify it meets the density requirements presented in the following table. Location Percent of Maximum Dry Percent Relative Density, Density-, ASTM Df - 557 ASTM D4253/D4254 ----------..__---_-—— ---- _ — - --------------- Beneath building, slabs, and paved 95 80 areas Other areas of fill and backfill, including backfill against the 90 75 outside of exterior foundation walls 4.2.3 Grading and Drainage All grades must provide effective drainage away from the structure during and after construction. Roof runoff and surface pad drainage should be collected and discharged away from the building to reduce wetting of the foundation soils. Inadequate drainage near the structure could result in unacceptable differential foundation or floor -slab movements, and cracked slabs and walls. Effective drainage should be maintained for the life of the building. 4.2.4 Earthwork Construction Considerations Exposed soils will likely be susceptible to rutting or pumping under construction traffic when wet. Soils that rut, pump, or are otherwise disturbed are not suitable for support of foundations, floor slabs, or pavements, and should be removed and replaced with Structural Fill. Measures that may help reduce disturbance of exposed soils include performing earthwork during warm, dry weather, the use of light track -mounted equipment, and avoidance of heavy repeated traffic over a given area. Grading operations should be controlled to prevent water from flowing into construction areas. Excessive wetting or drying of the foundation excavation soils should be avoided during construction. Excess water should be promptly removed. Responsive ■ Resourceful ■ Reliable 5 Geotechnical Engineering Report lf�rracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 The Contractor is responsible for designing and constructing stable, temporary excavations as required to maintain stability of the excavation sides and bottom, and for protecting existing facilities/utilities. Excavations should be sloped or shored in accordance with local, state, and federal regulations, including current OSHA excavation and trench safety standards. 4.3 Foundations The proposed structure can be supported on shallow spread footings. Design recommendations and construction considerations are presented in following subsections. 4.3.1 Spread Footing Recommendations Description Criteria Foundation type Conventional shallow spread footings. S„ Short period spectral response acceleration (Site Class B)' Undisturbed native soils or compacted Structural Fill Bearing material meeting the requirements of Section 4.2.2 of this report. The Structural Fill should be supported directly on undisturbed native soils. Net allowable bearing pressure 1,500 psf' Columns: 30 inches Minimum footing width Walls: 18 inches Minimum embedment depth below lowest Exterior footing: 24 inches (for frost protection) adjacent permanent finished grade or floor slab Interior footings not sub iact to frost: 18 inches Total: 1 inch or less Estimated settlement Differential: Typically '/ to % of the total settlement Ultimate coefficient of friction to resist 0.35 (This is an ultimate value, and does not include sliding a factor of safety. An appropriate factor of safety should be applied to this value for use in desi n. 1. The allowable bearing capacity may be increased by 1/3 for support of temporary loads such as those generated by wind and seismic events. 4.3.2 Foundation Construction Considerations Care should be taken when excavating the foundations to avoid disturbing the supporting soils. Soils that rut, pump, or are otherwise disturbed are not suitable for support of foundations and should be removed and replaced with compacted Structural Fill. 4.4 Seismic Considerations IBC' Seismic Design Parameters Description Value Site classification D S„ Short period spectral response acceleration (Site Class B)' 0.29g (for Site Class B) S7,1 second period spectral response acceleration (Site Class Bf 0.10g (for Site Class B) Responsive ■ Resourceful ■ Reliable 6 Geotechnical Engineering Report l�erracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 IBC' Seismic Design Parameters Description Value 1. Based on Section 1613 of the 2009 International Building Code (IBC). 2. Based on the 2009 IBC, the seismic site class is determined from a soil profile extending to a depth of 100 feet. The current scope requested does not include a boring to a depth of 100 feet. The borings for this project extended to a maximum depth of approximately 16% feet, and the seismic site classification assumes that soils similar to those encountered in the lower portions of the borings continue below the maximum depth of the subsurface exploration. If desired, a geophysical exploration could be performed to confirm the site classification, or possibly justify a more favorable site classification. 3. _ Accelerations shown above should be adjusted as required by the IBC to account for the Site Classification. na . 9F1P Description Criteria Interior floor system Slab -on -grade concrete Minimum 4 inches of 3/, -inch -minus crushed aggregate base' Floor slab support compacted in accordance with Section 4.2.2 of this report. Aggregate base should be supported on soils prepared in accordance with Section 4.2 of this report. 1. Aggregate base should meet the requirements of %-Inch (Type 1) crushed aggregate in the IS PWC, Section 802. The use of a vapor retarder should be considered beneath concrete slabs on grade that will be covered with wood, tile, carpet, or other moisture sensitive or impervious coverings, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer and slab contractor should refer to ACI 302 and ACI 360 for procedures and cautions regarding the use and placement of a vapor retarder. 4.6 Pavements Asphalt and concrete pavement section designs were based on the traffic estimates presented in Section 2.1. If traffic volumes will exceed the presented values, Terracon should be notified in order to provide pavement sections designed for higher levels of traffic. Design and construction considerations are also presented below. 4.6.1 Asphalt Pavement Sections An asphalt pavement section for this project was designed in general accordance with the National Asphalt Pavement Association (NAPA) publication "Design of Hot Mix Asphalt Pavements for Commercial, Industrial, and Residential Areas." The following flexible pavement section should be placed on subgrade soils prepared in accordance with Section 4.2. Material Thickness Asphalt concrete' 3inches Crushed aggregate base course (3/4 Inch — Type 1)' 9 inches Total thickness 12 inches 1. Asphalt concrete and aggregate base should conform to the applicable sections of the ISPWC. Responsive ■ Resourceful ■ Reliable 7 Geotechnical Engineering Report l��rr�con Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 Following subgrade preparation, the base aggregates should be moisture conditioned to near optimum moisture content, placed in uniform lifts, and compacted to at least 95 percent of the maximum dry density as determined by ASTM D1557. The asphalt concrete should be compacted to a minimum of 92.0 percent of the maximum theoretical density, as determined by AASHTO T 209. The asphalt concrete should meet ISPWC requirements for a '/z -inch maximum size Class III mix. Asphalt cement should be PG 58-28. 4.6.2 Portland Cement Concrete Pavement Sections A rigid pavement section was calculated in general accordance with the with the 1993 AASHTO Method and is presented in the following table. Material Thickness Portland Cement Concrete' 5 inches Crushed aggregate base course (3/4 Inch —Type 1)' 4 inches Total thickness 9 inches 1. Portland cement concrete and aggregate base should conform to the applicable sections of the ISPWC. For areas subject to concentrated and repetitive loading conditions such as dumpster pads, truck delivery docks and ingress/egress aprons, we recommend using the Portland cement concrete pavement section presented in the following table. For dumpster pads, the concrete pavement area should be large enough to support the container and tipping axle of the refuse truck. The following rigid pavement section should be placed on subgrade soils prepared in accordance with Section 4.2. Material Thickness Portland Cement Concrete' 7 inches Crushed aggregate base course (3/4 Inch — T Type 1)' 4 inches Total thickness 11 inches 1. Portland cement concrete and aggregate base should conform to the applicable sections of the ISPWC. As a minimum, the concrete pavements should be reinforced with 6 -inch by 6 -inch, W2.OxW2.0 welded wire mesh. Reinforcement of concrete with wire mesh does not prevent cracking of the concrete. However, the wire mesh aids in reducing the potential for opening of shrinkage cracks in the concrete. Wire mesh should be located approximately 2 inches below the top of the slab. Responsive ■ Resourceful ■ Reliable 8 Geotechnical Engineering Report l�erracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 An adequate number of longitudinal and transverse control joints should be placed in the rigid pavement in accordance with ACI and/or AASHTO requirements. Control joints should be saw cut ''/a of the depth of the concrete. Sawing should be performed as soon as the slab can be cut without inducing significant spalling (usually within 4 to 8 hours of concrete placement). Expansion (isolation) joints must be full depth and should only be used to isolate fixed objects abutting or within paved areas. Sealing of construction joints is essential to protect the subgrade and promote long term performance of concrete pavement. Sealing should occur as soon as possible (in accordance with sealant manufacturer's instructions) to reduce infiltration of water into the base course and subgrade. 4.6.3 Pavement Design Considerations Long-term pavement performance will be dependent on several factors, including reducing or preventing increases in subgrade moisture content and providing preventive maintenance. In general, increases in the moisture content of subsurface soils can result in adverse effects to the pavement section. These adverse effects typically result from frost susceptibility or loss of subgrade strength with increases in moisture content. Openings in the pavement surface, such as landscape islands, are sources for water infiltration into the surrounding pavement section and subgrade. Water can collect in the islands and migrate into the underlying subgrade soils, thereby degrading support of the pavement. This is especially applicable for islands with raised concrete curbs, irrigated vegetation, and near - surface soils with low permeability. The civil design for pavements with these conditions should include features to restrict or collect and discharge excess water from the islands. Examples of these features are edge drains connected to the storm -water collection system or other suitable outlet and impermeable barriers that reduce lateral migration of water such as a cutoff wall installed to a depth below the pavement section. The following should be considered as minimum recommendations in the design and construction of pavements: ■ Provide a minimum 2% grade in the ground surface away from the edge of pavements. ■ Provide a minimum 2% cross slope for the subgrade and pavement surface to promote proper surface drainage. ■ Install pavement drainage at the perimeter of areas where frequent wetting, such as from irrigation or other sources of water, is anticipated. ■ Install joint sealant and seal cracks promptly. ■ Seal all landscaped areas adjacent to pavements to reduce moisture migration to subgrade soils. ■ Place compacted low -permeability backfill against the exterior side of curb and gutter. Responsive ■ Resourceful ■ Reliable 9 Geotechnical Engineering Report l�erracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 Preventive maintenance should be planned and provided as a part of an asphalt pavement management program. These maintenance activities are intended to slow the rate of pavement deterioration and to preserve the pavement investment. Preventative maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching) and global maintenance (e.g. surface sealing for asphalt pavements). This type of maintenance is usually the first priority when implementing a planned pavement maintenance program and generally provides a relatively high return on investments for pavements. Even with periodic maintenance, some movements and related cracking may still occur and require repair. 4.6.4 Pavement Construction Considerations Pavement sections should be placed on properly prepared subgrade, as described in Section 4.2 of this report. As construction proceeds, the subgrade may be disturbed or altered due to utility excavations, construction traffic, desiccation, or rainfall. As a result, the subgrade may become unsuitable for pavement support. The long-term effects of localized areas of inadequately prepared subgrade may result in cracks or potholes in the pavement. Therefore, the subgrade should be carefully evaluated at the time of paving for signs of disturbance or excessive rutting. If disturbance or rutting has occurred, subgrade areas should be reworked, moisture conditioned, and properly compacted to the recommendations in this report immediately prior to constructing the pavement section asphalt or Portland cement concrete. In areas of prepared subgrade or partial thickness pavement, the Contractor should limit traffic to equipment necessary to construct the pavement section. Heavily loaded vehicles operating on these surfaces may cause significant damage, resulting in deterioration and reduction in pavement life. 5.0 GENERAL COMMENTS Terracon should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications. Terracon also should be retained to provide observation and testing services during grading, excavation, foundation construction, and other earth -related construction phases of the project. The analysis and recommendations presented in this report are based upon the data obtained from the borings performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between borings, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. Responsive ■ Resourceful ■ Reliable 10 Geotechnical Engineering Report l�erracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, and bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing. Responsive ■ Resourceful ■ Reliable 11 APPENDIX A FIELD EXPLORATION Geotechnical Engineering Report l��rracon Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 Field Exploration Description The subsurface exploration consisted of drilling six borings in the proposed project area. The approximate locations of the explorations are shown on the Boring Location Plan included in this appendix. The boring locations were selected by O'Reilly Automotive Stores, Inc. The borings were located in the field by Terracon by measuring with a distance wheel from existing site features. Relative ground -surface elevations at the boring locations were measured by Terracon using an engineer's level. Relative elevations reported on the boring logs are rounded to the nearest 1/2 foot. The top of a manhole cover in the southwest portion of the project area was used as a temporary benchmark (TBM). The elevation of the TBM was assumed to be 100 feet. The approximate location of the TBM is shown on the Boring Location Plan presented in this appendix. The locations and elevations of the borings should be considered accurate only to the degree implied by the means and methods used to define them. The borings were drilled to depths ranging from about 151/2 to 16'/ feet below the existing ground surface with a truck -mounted drill rig equipped with continuous -flight hollow -stem augers. A Terracon field geologist recorded logs of the borings during the drilling operations. Disturbed soil samples were obtained at various depths in the borings using a 2 -inch - outside -diameter split -spoon sampler driven in general accordance with the Standard Penetration Test (SPT). The result of the SPT is an N -value. The N -value is the number of blows from a 140 -pound hammer falling from a height of 30 inches that are required to drive the split -spoon sampler the last 12 inches of an 18 -inch interval (or the distance indicated). N -values are shown on the boring logs. In addition, disturbed bulk soil samples were obtained from the auger cuttings. Descriptions of the materials encountered are presented on the boring logs in this appendix. The N -value provides a reasonable estimate of the relative in-place density of non-cemented sandy type materials. However, the N -value only provides an indication of the relative stiffness of cohesive materials, since the penetration resistance of these soils may be affected by the moisture content. Considerable care must be exercised in interpreting the N -value in gravelly soils, particularly where the size of the gravel particles exceeds the inside diameter of the sampling spoon. An automatic SPT hammer was used to advance the split -spoon sampler in the borings performed on this site. A greater efficiency is typically achieved with the automatic hammer compared to the conventional safety hammer operated with a cathead and rope. Published correlations between the SPT values and soil properties are based on the cathead and rope method. The higher efficiency of the automatic hammer affects the standard penetration resistance blow count (N -value) by increasing the penetration per hammer blow over what would be obtained using the cathead and rope method. The effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of the subsurface information for this report. Responsive ■ Resourceful ■ Reliable Exhibit A-3 DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES BASED ON A DRAWING FROM GOGGLE EARTH PRO F"den manaaer: VICINITY MAP Exhibit RJO Drawn by. TMA erracon PROPOSED O'REILLY AUTO PARTS STORE Checked by: RJO P03/N25O0/MlS2' Consulting Engineers&Scientits 3377 NORTH TEN MILE ROAD A_1 Approved by. ,mew=„e.,�ew °.,,. e�„ea .�a.b a=�,= MERIDIAN, IDAHO RJO ee.laml anesro Fna121e, 121e1e2 NOTES: LEGEND: 1. Locations are approximate. 2. Temporary benchmark (TBM) is the top of a manhole cover. TBM has an assumed elevation of 100 feet. 3. Based on drawing provided by O'Reilly Automotive Stores, Inc. - 4. For general location use only, not intended for construction purposes. ....... � . 6212L09 1 rerracon S ale: 1J" FIIe Name: Consulting Engineers & Scientists 3o,,W. ..e Plen Dale: „uewa.,o�u.. onw, s�lao m.x,iam eJ Approximate Boring Location Temporary Benchmark (TBM) BORING LOCATION PLAN FIG No. PROPOSED O'REILLY AUTO PARTS STORE 3377 NORTH TEN MILE ROAD A_2 MERIDIAN, IDAHO i A `YMY f �VLY [ YS AaRIAM AI II IXISTNC LOT ME — J II IwI III is I A l��iOPE a.00' 1 _ i B-2 I 5i II B- I a I I I J II - I I MASONRY B -5M. a fF z L B-6 I»{- I m- MEANI woE nccEss NW,�.r=A� _ mow LOT IINE &� I N-Lxmnmc / 5 Pe,E it NVACANT I- I LAN,, @UTA for a sax � II.<�rW n W I � LI@Y'pYL ®SIR /f. " II11wl / m m / s(�l/ml/r �aLa I /OAr l/1 IN AR -/.i/1 A NOTES: LEGEND: 1. Locations are approximate. 2. Temporary benchmark (TBM) is the top of a manhole cover. TBM has an assumed elevation of 100 feet. 3. Based on drawing provided by O'Reilly Automotive Stores, Inc. - 4. For general location use only, not intended for construction purposes. ....... � . 6212L09 1 rerracon S ale: 1J" FIIe Name: Consulting Engineers & Scientists 3o,,W. ..e Plen Dale: „uewa.,o�u.. onw, s�lao m.x,iam eJ Approximate Boring Location Temporary Benchmark (TBM) BORING LOCATION PLAN FIG No. PROPOSED O'REILLY AUTO PARTS STORE 3377 NORTH TEN MILE ROAD A_2 MERIDIAN, IDAHO LOG OF BORING NO. B-1 Page 1 of 1 OWNER PROJECT O'Reilly Auto Parts Proposed O'Reilly Auto Parts Store SITE 3377 N Ten Mile Road, Meridian, Idaho SAMPLES TESTS a w o� DESCRIPTION F �a o a W a W O ?� z Ww mJ N O UW �z WF z <3 l_ ((7 Approx. Surface Elev.: 99.5 ft o a MW 3 o ¢ ?, 0.5 (FILLI SILT WITH SAND AND GRAVEL; 99 SS 0.3 6 moist, brown (CL) SANDY LEAN CLAY; medium stiff to very stiff, moist, trace gravel, brown 2 3 96.5 SS 1.2 51 (GP -GM TO GPI GRAVEL WITH SILT AND SAND TO GRAVEL WITH SAND; OD medium dense to very dense, moist to wet, 4 brown oD SS 0.9 20 6 0 s oD SS 1.0 32 8 o D O OD 10 Q° SS 1.4 60 OD QO 12 OD 14 85:5 14 (SP -SM) SAND WTIH SILT; medium dense, wet, light brown SS 1.2 19 16 :. 18.5 83 BOTTOM OF BORING The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL DEPTH(S), it 1 �� rr acon BORING STARTED 3-13-12 WL� 7 5 WD = BORING COMPLETED 3-13-12 RIG CME -75 I LOGGED BY BLP WL 2 WL APPROVED RJO JOB# 62125009 LOG OF BORING NO. B-2 Page 1 of 1 OWNER PROJECT O'Reilly Auto Parts Proposed O'Reilly Auto Parts Store SITE 3377 N Ten Mile Road, Meridian, Idaho SAMPLES TESTS 3 0 W W co ) n DESCRIPTION �� o ❑� U d W Ja W O ?� ZmJ wl- N O UW Q_ 2 Krri U F p � z W~ z g3 w Approx. Surface Elev.: 100 ft o W it ran m 3 0 ¢ 7 Zn 0.5 (FILL) SILTY SAND WITH GRAVEL; 995 SS 1.0 9 moist, brown (ML) SANDY SILT: moist, trace gravel, brown 2 98 2 (CL) LEAN CLAY: stiff, moist, brown SS 1.2 8 23 34/14 4 trace gravel at 5' SS 0.8 9 6- 6.5 93.5 (GM) SILTY GRAVEL WITH SAND; dense to very dense, moist to wet, light brown SZ SS 1.0 49 8 SS 0.9 50/0.5 10 12 13.5 66.5 (SP) SAND: dense, wet, light brown 1a SS 0.0 33 16 16.5 63.5 BOTTOM OF BORING The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL DEPTH(S), ft 1 ��rr acon BORING STARTED 3-13-12 WL � B WD = BORING COMPLETED 3-13-12 WL RIG CME-751 LOGGED BY BLP WL APPROVED RJO JOB# 62125009 LOG OF BORING NO. B-3 Page 1 of 1 OWNER PROJECT O'Reilly Auto Parts Proposed O'Reilly Auto Parts Store SITE 3377 N Ten Mile Road, Meridian, Idaho SAMPLES TESTS LU a LU o(D U DESCRIPTION C F Wa W J o N W a = W a W O zm wF Kai O W 43 0 a o W U M f0 �Z 3 w z a~ Approx. Surface Elev.: 101 It aim U ¢ _° (FILL I MIXTURE OF SILT, CLAY, SAND, SS 0.2 10 1 AND GRAVEL: 100 moist, brown (CL) LEAN CLAY: stiff, moist, brown 2 3 96 1.1 11 MI LI SILT; stiff, moist, brown 4- 4.5 96.5 (CL) LEAN CLAY: soft to medium stiff, moist, brown 1.2 4 6 7.5 93.5 (GP-GM) GRAVEL WITH SILT AND 0.4 51 SANDo 6 dense to very dense, moist to wet, light brown 0 0 10__0.9 38 0 12 13 88 e �o (GP) GRAVEL WITH SAND: very dense, wet, interbedded clay lenses. OD light brown 14 oQD 1.5 81 o D 16.5 84.5 1s BOTTOM OF BORING The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL DEPTH(S), ft 1 ��rr�con BORING STARTED 3-13-12 WLg 8.5 WD � BORING COMPLETED 3-13-12 RIG CME-751 LOGGED BY BLP WL $ s WL I APPROVED RJO I JOB# 62125009 LOG OF BORING NO. B-4 Page 1 of 1 OWNER PROJECT O'Reilly Auto Parts Proposed O'Reilly Auto Parts Store SITE 3377 N Ten Mile Road, Meridian, Idaho SAMPLES {TESTS > n n W o o o= DESCRIPTION > ~ �a C7 U a C LU a o ?3 ul W w� N W g3 Wz z � Approx. Surface Elev.: 101 ft o w W WED 3 o a M (FILL) MIXTURE OF SILT, SAND, AND SS 1.1 11 GRAVEL: moist, brown 1.5 99.5 (CL) LEAN CLAY WITH SAND: very stiff, moist, brown 2 SS 1.4 35 3.5 97.5 4 (GP-GM TO GP) GRAVEL WITH SILT AND SAND TO GRAVEL WITH SAND; OD dense to very dense, moist to wet, light brown SS 1.1 57 OD s C)° D O SS 1.3 74 o D V6 O OD o D O 1U SS 1.1 88 OD 12 OD QO 14 OD SS 1.0 60 � 00 O 16 ° 16.5 84.5 BOTTOM OF BORING The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL DEPTH(S), ft l��rr�con BORING STARTED 3-13-12 WL 4WD =8 BORING COMPLETED 3-13-12 RIG CME-75 LOGGED BY BLP WL WL APPROVED RJO JOB# 62125009 LOG OF BORING NO. B-5 Page 1 of 1 OWNER PROJECT O'Reilly Auto Parts Proposed O'Reilly Auto Parts Store SITE 3377 N Ten Mile Road, Meridian, Idaho SAMPLES TESTS > b w n DESCRIPTION U u1 w a F a O wf MFC O <3 K w U F-Z3 O QO F� ? a2 0 Approx. Surface Elev.: 100.5 ft o 0 It vai m 0.5 (FILL) SILTY SAND WITH GRAVEL; 100 SS 1.0 13 (CL-ML) SILTY CLAY: stiff, moist, brown 2 2.5 98 SS 1.4 84 (GP-GM TO GP) GRAVEL WITH SILT AND SAND TO GRAVEL WITH SAND; OD dense to very dense, moist to wet, light brown q on SS 1.1 48 OD 6 a �o QD SS 0.6 50/0,4 Q$ OD 10 SS 0.8 50/0.5 OD �o 12 oOD OD 14 o Qa o D O 15.4 85.1 SS 0.3 50/0.4 BOTTOM OF BORING The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL DEPTH(S), ft 1 �� rr acon BORING STARTED 3-13-12 WL4 8 5 WD = BORING COMPLETED 3-13-12 RIG CME-75 LOGGED BY BLP WL g WL APPROVED RJO JOB # 62125009 LOG OF BORING NO. B-6 Page 1 of 1 OWNER PROJECT O'Reilly Auto Parts Proposed O'Reilly Auto Parts Store SITE 3377 N Ten Mile Road, Meridian, Idaho SAMPLES TESTS > T W No n a= DESCRIPTION > �a U a W a WZ o ?3 w�WF mJ N o UW ¢3 �z z Approx. Surface Elev.: 102 ft o 0 M w m o ¢ ? Z, (FILL) MIXTURE OF SILT, CLAY, SAND, SS 1.5 11 24 47/25 AND GRAVEL; 1 tot moist, brown BS 10 lbs (CL) LEAN CLAY: 2 stiff, moist, brown too 2 (ML) SANDY SILT: SS 1.4 53 14.5 hard, moist, moderately cemented, light brown a 97.5 (SM TO ML) SILTY SAND TO SANDY a!LL SS 1.3 48 dense, moist, light brown s 6.5 95.5 o � (GP -GMT GP) GRAVEL WITH SILT AND SAND TO GRAVEL WITH SAND; OD medium dense to very dense, wet, light SS 0.4 25 �a brown 8 o D � O o �a o D a a �o 10 SS 0.6 16 OD 12- 214OOD 14- 0 SS 1.2 84 O 16 — 16.5 85.5 BOTTOM OF BORING The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL DEPTH(S), ft 1 �� rr acon BORING STARTED 3-13-12 WL7 8 5 WD i BORING COMPLETED 3-13-12 RIG CME -75 FLOGGED BY BLP WL SE 4 WL I APPROVED RJO JOB# 62125009 APPENDIX B LABORATORY TESTING Geotechnical Engineering Report l�err�con Proposed O'Reilly Auto Parts Store ■ Meridian, Idaho March 21, 2012 ■ Terracon Project No. 62125009 Laboratory Test Description Samples obtained during the field exploration were transferred to the laboratory and visually classified in general accordance with the Unified Soil Classification System described in Appendix C. Representative samples were selected for testing to determine physical and engineering properties of the subsurface materials. Following are the laboratory tests conducted and a brief description of the purpose of each test: Test Conducted To Determine: Natural moisture content Moisture content of the sample. Atterberg limits Plasticity of the sample. Results of the laboratory tests are summarized on the boring logs in Appendix A. Responsive ■ Resourceful ■ Reliable Exhibit B-1 APPENDIX C SUPPORTING DOCUMENTS The number of blows required to advance a standard 2 -inch O.D. split -spoon sampler (SS) the last 12 inches of the total 18 -inch penetration with a 140 -pound hammer falling 30 inches is considered the "Standard Penetration' or "N -value'. WATER LEVEL MEASUREMENT SYMBOLS: GENERAL NOTES Unconfined Standard Penetration WL: Water Level WS: DRILLING & SAMPLING SYMBOLS: BCR: Before Casing Removal WCI: Wet Cave in WD: SS: Split Spoon - 1-3/8" I.D., 2" O.D., unless otherwise noted HS: Hollow Stem Auger ST: Thin -Walled Tube - 2" O.D., 3" O.D., unless otherwise noted PA: Power Auger (Solid Stem) RS: Ring Sampler - 2.42" I.D., 3" O.D., unless otherwise noted HA: Hand Auger DB: Diamond Bit Coring -4", N, B RB: Rock Bit BS: Bulk Sample or Auger Sample WB Wash Boring or Mud Rotary The number of blows required to advance a standard 2 -inch O.D. split -spoon sampler (SS) the last 12 inches of the total 18 -inch penetration with a 140 -pound hammer falling 30 inches is considered the "Standard Penetration' or "N -value'. WATER LEVEL MEASUREMENT SYMBOLS: RELATIVE DENSITY OF COARSE-GRAINED SOILS Unconfined Standard Penetration WL: Water Level WS: While Sampling BCR: Before Casing Removal WCI: Wet Cave in WD: While Drilling ACR: After Casing Removal DCI: Dry Cave in AB: After Boring N/E: Not Encountered Water levels indicated on the boring logs are the levels measured in the borings at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-term observations. DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non -plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency. CONSISTENCY OF FINE-GRAINED SOILS RELATIVE DENSITY OF COARSE-GRAINED SOILS Unconfined Standard Penetration Standard Penetration Dry Weight Compressive or N -value (SS) Consistency or N -value (SS) Relative Density Strength, Qu, Ps f Blows/Ft. > 12 Blows/Ft. < 500 0 - 1 Very Soft 0-3 Very Loose 500-1,000 2-4 Soft 4-9 Loose 1,000-2,000 4-8 Medium Stiff 10-29 Medium Dense 2,000 - 4,000 8-15 Stiff 30-50 Dense 4,000 - 8,000 15-30 Very Stiff > 50 Very Dense 8,000+ > 30 Hard RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY Descriptive Term(s) Percent of Maior Component Particle Size of other constituents Dry Weight of Sample Trace < 15 Boulders Over 12 in. (300mm) With 15-29 Cobbles 12 in. to 3 in. (300mm to 75mm) Modifier >- 30 Gravel 3 in. to #4 sieve (75mm to 4.75mm) Sand #4 to #200 sieve (4.75 to 0.075mm) Silt or Clay Passing #200 Sieve (0.075mm) RELATIVE PROPORTIONS OF FINES Descriptive Term(s) Percent of J other constituents Dry Weight Trace < 5 With 5-12 Modifier > 12 Rev 04/10 1 rerracon PLASTICITY DESCRIPTION Term Plasticity — Index Non -plastic 0 Low 1-10 Medium 11-30 High > 30 Exhibit C-1 UNIFIED SOIL CLASSIFICATION SYSTEM " Based on the material passing the 3 -in. (75 -mm) sieve e If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. Gravels with 5 to 12% fines require dual symbols: GW -GM well -graded gravel with silt, GW -GC well -graded gravel with clay, GP -GM poorly graded gravel with silt, GP -GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW -SM well -graded sand with silt, SW -SC well -graded sand with clay, SP -SM poorly graded sand with silt, SP -SC poorly graded sand with clay s Cu = D,/D,, Cc = 22 Dro x D80 y If soil contains >_ 15% sand, add "with sand" to group name. G If fines classify as CL -ML, use dual symbol GC -GM, or SC -SM. :1 X W 0 }Z F U F - g a 60 For classification of fine-grained soils and fine-grained fraction ' 50 —of coarse-grained soils \l �, Equation of "A" - line aJ�' +Pv Horizontal at PI=4 to LL=25.5. then P1=0.73 (LL -20) ' 0+ Equation of 'U"- line j+( Vertical at LL=16 to PI=7, then P1=0.9 (LL -8) ' �V MH or OH r_ L- L ML or OL ' " If fines are organic, add "with organic fines" to group name. If soil contains z 15% gravel, add "with gravel" to group name. ' If Atterberg limits plot in shaded area, soil is a CL -ML, silty clay. " If soil contains 15 to 29% plus No. 200, add'With sand" or Wth gravel," whichever is predominant. L If soil contains z 30% plus No. 200 predominantly sand,. add "sandy" to group name. If soil contains >_ 30% plus No. 200, predominantly gravel, add "gravelly" to group name. " PI 2 4 and plats on or above "A" line. 0 PI <4 or plots below "A" line. P PI plots on or above "A" line. ° PI plots below "A" line. 40 30 II 10 7 4 0 10 16 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT (LL) Exhibit C-2 Silts and Clays: PI <4 or plots below "A" line Soil Classification Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests" Group Liquid limit less than 50 Liquid limit -oven dried Organic day" ,L,I," Group Names Organic: <0.75 Liquid limit - not dried Symbol m,0 Organic silo Gravels: Clean Gravels: Cu >_ 4 and 1 < Cc S 3 E GW Well -graded gravel F More than 50% of Less than 5%fines ° Cu<4 and/or 1>Cc>3s GP Poorly graded gravely coarse fraction retained Gravels with Fines: Fines classify as ML or MH GM Silty gravel F 0•" Coarse Grained Soils: on No. 4 sieve More than 50% More than 12% fines 0 Fines classify as CL or CH GC Clayey gravel •G retained Liquid limit - not dried <0.75 OH Organic silt Highly organic soils: on No. 200 sieve Sands: Clean Sands: Cu>_6and 1<Cc<3' SW Well -graded sand 50% or more of coarse Less than 5% fines ° Cu < 6 and/or 1 > Cc> 3E SP Poorly graded sand' fraction passes No. 4 Sands with Fines: Fines classify as ML or MH SM Silty sand G," ' sieve More than 12% fines 0 Fines classify as CL or CH SC Clayey sand 0• • PI > 7 and plots on or above line' CL Lean clay "• •" Inorganic: JA" " Based on the material passing the 3 -in. (75 -mm) sieve e If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. Gravels with 5 to 12% fines require dual symbols: GW -GM well -graded gravel with silt, GW -GC well -graded gravel with clay, GP -GM poorly graded gravel with silt, GP -GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW -SM well -graded sand with silt, SW -SC well -graded sand with clay, SP -SM poorly graded sand with silt, SP -SC poorly graded sand with clay s Cu = D,/D,, Cc = 22 Dro x D80 y If soil contains >_ 15% sand, add "with sand" to group name. G If fines classify as CL -ML, use dual symbol GC -GM, or SC -SM. :1 X W 0 }Z F U F - g a 60 For classification of fine-grained soils and fine-grained fraction ' 50 —of coarse-grained soils \l �, Equation of "A" - line aJ�' +Pv Horizontal at PI=4 to LL=25.5. then P1=0.73 (LL -20) ' 0+ Equation of 'U"- line j+( Vertical at LL=16 to PI=7, then P1=0.9 (LL -8) ' �V MH or OH r_ L- L ML or OL ' " If fines are organic, add "with organic fines" to group name. If soil contains z 15% gravel, add "with gravel" to group name. ' If Atterberg limits plot in shaded area, soil is a CL -ML, silty clay. " If soil contains 15 to 29% plus No. 200, add'With sand" or Wth gravel," whichever is predominant. L If soil contains z 30% plus No. 200 predominantly sand,. add "sandy" to group name. If soil contains >_ 30% plus No. 200, predominantly gravel, add "gravelly" to group name. " PI 2 4 and plats on or above "A" line. 0 PI <4 or plots below "A" line. P PI plots on or above "A" line. ° PI plots below "A" line. 40 30 II 10 7 4 0 10 16 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT (LL) Exhibit C-2 Silts and Clays: PI <4 or plots below "A" line ML Silt Liquid limit less than 50 Liquid limit -oven dried Organic day" ,L,I," Fine -Grained Soils: Organic: <0.75 Liquid limit - not dried OL m,0 Organic silo 50% or more passes the No. 200 sieve PI plots on or above "A" line CH Fat clay Silts and Clays: Inorganic: PI plots below "A" line MH Elastic Silt "m Liquid limit 50 or more Liquid limit - oven dried Organic Clay "• A Organic: Liquid limit - not dried <0.75 OH Organic silt Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat " Based on the material passing the 3 -in. (75 -mm) sieve e If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. Gravels with 5 to 12% fines require dual symbols: GW -GM well -graded gravel with silt, GW -GC well -graded gravel with clay, GP -GM poorly graded gravel with silt, GP -GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW -SM well -graded sand with silt, SW -SC well -graded sand with clay, SP -SM poorly graded sand with silt, SP -SC poorly graded sand with clay s Cu = D,/D,, Cc = 22 Dro x D80 y If soil contains >_ 15% sand, add "with sand" to group name. G If fines classify as CL -ML, use dual symbol GC -GM, or SC -SM. :1 X W 0 }Z F U F - g a 60 For classification of fine-grained soils and fine-grained fraction ' 50 —of coarse-grained soils \l �, Equation of "A" - line aJ�' +Pv Horizontal at PI=4 to LL=25.5. then P1=0.73 (LL -20) ' 0+ Equation of 'U"- line j+( Vertical at LL=16 to PI=7, then P1=0.9 (LL -8) ' �V MH or OH r_ L- L ML or OL ' " If fines are organic, add "with organic fines" to group name. If soil contains z 15% gravel, add "with gravel" to group name. ' If Atterberg limits plot in shaded area, soil is a CL -ML, silty clay. " If soil contains 15 to 29% plus No. 200, add'With sand" or Wth gravel," whichever is predominant. L If soil contains z 30% plus No. 200 predominantly sand,. add "sandy" to group name. If soil contains >_ 30% plus No. 200, predominantly gravel, add "gravelly" to group name. " PI 2 4 and plats on or above "A" line. 0 PI <4 or plots below "A" line. P PI plots on or above "A" line. ° PI plots below "A" line. 40 30 II 10 7 4 0 10 16 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT (LL) Exhibit C-2