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HomeMy WebLinkAboutSW3221203_Soils/Geotechnical Report_20221216March 31, 2022 Fiorenza Properties, LLC GEQSCIENCE 118 East Kingston Avenue, Suite 16 GROUP Charlotte, North Carolina 28203 Attention: Ms. Bridget McClellan Operations Manager Reference: Report Of Geotechnical Subsurface Exploration McCanless Road Subdivision Salisbury, North Carolina Geoscience Project No. CH22.002 LGE Consulting Engineers Geoscience Group, Inc. (Geoscience) has completed the subsurface exploration and geotechnical evaluation for the referenced project. This work was performed in general accordance with Geoscience Proposal No. CH22.047P.GE. The purpose of this exploration was to determine the general subsurface conditions at the site and to evaluate those conditions with regard to foundation support and site development. This report presents our findings along with our geotechnical conclusions and recommendations for design and construction of the project. SCOPE OFE"LOR,47TON Field Services: The subsurface exploration included the execution of twelve (12) soil test borings (B-1 through B-12) at the approximate locations shown on the Boring Location Diagram, Drawing No. CH22.0021.GE-1, included in the Appendix. The boring locations were established in the field by an engineer from Geoscience using the February 9, 2022, project drawing entitled Preliminary Site Plan prepared by Alley, Williams, Carmen & King Inc., a handheld GPS unit and the existing site features as reference. The soil test borings were extended to depths ranging from approximately 10 to 20 feet below the ground surface using continuous -flight, hollow -stem augers. Drilling fluid was not used during this process. Standard Penetration Tests were performed in the soil test borings at designated intervals using an automatic hammer in general accordance with ASTM D 1586-84. A correction factor has been used for our analysis of the Standard Penetration Tests with the automatic hammer assembly; however, the N-values reported on the Test Boring Records are the field recorded values. In conjunction with the penetration testing, split -spoon soil samples were recovered at each test depth and placed in plastic resealable bags. All soil samples were returned to our laboratory for soil classification and laboratory testing. A brief description of the field testing procedures and copies of the Test Boring Records are included in the Appendix. Elevations shown on the Test Boring Records and referenced within -this report were interpolated from the above referenced project drawing and should be considered approximate. 500 Clanton Road Charlotte, North Carolina Telephone Facsimile NC License Suite K 28217 704.525,2003 704.525.2051 F-0585 Fiorenza Properties, LLC Geoscience Project No. CH22.0021.GE March 31, 2022 Page 2 Laboratory Services: The laboratory services provided for this project included visual classification of the soil samples by the project geotechnical engineer. The color, texture and plasticity characteristics were used to identify each soil sample in general accordance with the Unified Soil Classification System (USCS). In addition, Atterberg Limits tests and natural moisture content determinations were performed on select split -spoon soil samples to further assess the plasticity characteristics and moisture conditions of the near -surface soils. The results of the visual classifications, Atterberg Limits tests and natural moisture content determinations are presented on the Test Boring Records. SITE AND SUBSURFACE FINDINGS Site: The 20.7f acre project site (Rowan County Parcel ID No. 5770-04-50-8920) is located in the southeast quadrant formed by the intersection of McCanless Road and Choate Road in Salisbury, North Carolina. The project site is currently undeveloped with the groundcover consisting of agricultural fields and wooded areas. In addition, drainage features extend across the northeastern and southeastern portions of the site. At the time our field services were performed, soft, saturated near-surfacc soils were observed in the vicinity of the drainage features. The ground surface across the project site generally slopes downward from the north toward the south and east. A high elevation of approximately 737 feet (MSL) is present in the northwestern corner of the site, and a low elevation of approximately 686 feet (MSL) is present in the southeastern portion. Subsurface: The subsurface conditions at the site, as indicated by the soil test borings, generally consist of a residual soil profile which has formed from the in -place weathering of the underlying parent bedrock. The generalized subsurface conditions are described below and illustrated on the Generalized Subsurface Profiles, Drawing Nos. CH22.002 LGE-2 and CH22.002 LGE-3, included in the Appendix. For soil descriptions and general stratification at a particular boring location, the respective Test Boring Record should be reviewed. Commencing at the ground surface in all the soil test borings, an upper layer of topsoil and roots was encountered to depths ranging from approximately % to 1 foot. AIso, it should be noted that the root mat of large trees can be quite extensive and normally extends a minimum of 2 to 3 feet below the ground surface. Subjacent to the topsoil in soil test borings B-1, B-2, B-4, B-5, B-8, B-10 and B-11, residual very silty CLAY and very clayey SILT soils were encountered to a depth of approximately 3 feet below the ground surface. The Standard Penetration Test results within these residual very clayey soils range between 10 and 19 Blows Per Foot (BPF). In addition, the natural moisture contents of these residual very silty CLAY and very clayey SILT soils range from approximately 22 4 to 38 % percent, the liquid limits range from 52 to 79 percent, and the plasticity indices range from 30 to 47 percent. The residual very silty CLAY and very clayey SILT soils are depicted in orange on the Generalized Subsurface Profiles. Fiorenza Properties, LLC Geoscience Project No. CH22.002LGE March 31, 2022 Page 3 Residual clayey SILT, sandy SILT and silty SAND soils, with varying amounts of mica, are present beneath the topsoil and/or residual very silty CLAY and very clayey SILT soils in all the soil test borings performed for this phase of the project. These residual SILT and SAND soils extend to depths ranging from approximately 3 to 20 feet below the ground surface. The Standard Penetration Test results within these residual SILT and SAND soils range from 8 to 79 BPF. Also, the natural moisture contents of these residual clayey SILT, sandy SILT and silty SAND soils range from approximately 15% to 51 percent. Partially Weathered Rock: Partially weathered rock was initially encountered in soil test borings B-3, B-11 and B-12 at depths ranging from approximately 3 to 8 feet below -he ground surface. These depths to the beginning of partially weathered rock correspond to elevations ranging from approximately 695 to 715 feet (MSL). For engineering purposes, partially weathered rock is considered any dense residual soil exhibiting a Standard Penetration Resistance value in excess of 100 BPF. When sampled, the partially weathered rock generally consists of silty SAND soils. The partially weathered rock is depicted in green on the Generalized Subsurface Profiles. Groundwater Observations: Groundwater measurements were attempted at the completion of each soil test boring and again at the conclusion of the drilling activities. No measurable groundwater was observed in any of the soil test borings performed for this phase of the project. However, moist to very moist soil conditions were observed in most of the soil test borings; these zones of moist to very moist soil conditions are shown on the Test Boring Records. PROJECT DESCRIPTION The proposed project will include the construction of multiple single-family homes with supporting pavement areas. In addition, a detention pond and lift station will be located in the southeastern portion of the site. The currently proposed site layout is shown on the Boring Location Diagram. Structural loading information and finished grades were not available at the time this report was prepared; however, due to the topographic relief across the project site, modular block retaining walls may be utilized to facilitate the final grades. CONCLUSIONSAND RECOMMENDATIONS The soil test borings performed at this site represent the subsurface conditions at the test locations only. Due to the prevailing geology, there can be changes in the subsurface conditions over relatively short distances that have not been disclosed by the results of the borings performed. Consequently, there may be undisclosed subsurface conditions that require special treatment or additional preparation once these conditions are revealed during construction. Fiorenza Properties, LLC Geoscience Project No. CH22.002LGE March 31, 2022 Page 4 Our conclusions and recommendations are based on the project description outlined above and on the data obtained from our field testing program. Changes in the project or variations in the subsurface conditions may require modifications to our recommendations. Therefore, as the project plans are finalized, we will require the opportunity to review our recommendations in light of the new design information and make any necessary changes. PROJECT DESIGN Building Su ort: Provided the recommendations outlined herein are implemented, the future homes can be adequately supported on shallow foundation systems consisting of spread footings bearing on suitable residual soils or on newly -placed structural fill. A net allowable bearing pressure of up to 3,000 pounds per square foot (PSF) can be used for design of the foundations. The net allowable bearing pressure is that pressure which may be transmitted to the soil in excess of the minimum surrounding overburden pressure. Minimum wall and column footing dimensions of 16 and 24 inches, respectively, should be maintained to reduce the possibility of a localized, "punching" type, shear failure. Exterior foundations and foundations in unheated areas should be designed to bear at least 18 inches below finished grades for frost protection. Slab -on -grade floor systems can be adequately supported on suitable residual soils or on newly -placed structural fill provided the site preparation and fill recommendations outlined herein are implemented. The floor slabs should be structurally isolated from the building foundations to allow independent movement. Also, we recommend that a granular material be placed immediately beneath the floor slabs to provide a capillary barrier and to increase the load distribution capabilities of the floor slab system. Furthermore, the use of a moisture barrier should be considered to reduce the potential for moisture transmission through the slabs. However, proper curing techniques must be employed when using a moisture barrier to prevent uneven curing. Seismic Design Parameters: Review of the North Carolina Building Code (NCBC) and the results of the soil test borings indicate that a Site Class C Category should be used for seismic design. Exterior Pavements: Design of the project pavements was beyond the scope of services provided herein. Suitable residual soils or newly -placed structural fill can provide adequate support for a pavement system designed for the appropriate subgrade strength and traffic characteristics. The pavement subgrade should be prepared in accordance with the site preparation and fill recommendations provided in this report. The subgrade and the pavement surface should be sloped to a suitable outlet area to provide positive subsurface and surface drainage away from the pavement. Water within the base course layer and ponded water on the pavement surface can lead to softening of the subgrade and other problems that will result in accelerated deterioration of the pavement system. Fiorenza Properties, LLC Geoscience Project No. CH22.0021.GE March 31, 2022 Page 5 Modular Block Retaining Walls: Based on the topographic relief across the project site, modular block retaining walls may be utilized to facilitate the final site grades. Our experience with modular block retaining wall design and construction indicates that the reinforced zone of the wall system is typically designed to consist of a granular soil with a minims SAND content of 65 percent, and a Plasticity Index and Liquid Limit less than 15 and 40 percent, respectively. Utilizing a granular soil within the reinforced zone of the wall system will minimize the amount of lateral movement and the resulting crack that occurs at the ground surface at the end of the reinforcing material. Based on the soil types encountered at the site, it appears that the onsite very sandy SILT soils, silty SAND soils and weathered rock materials will likely meet these typical reinforced zone parameters. These soils were limited to borings B-1, B-3, B-6, B-11 and B-12. As a result, it may be necessary to import soils or mine portions of the site for sandier backfill material for wall construction. In addition, consideration should be given to construction phasing so that any suitable wall backfill material encountered in the cut areas is stockpiled for use at the time of wall construction. Also, triaxial shear testing must be performed on the onsite soils in order to provide strength parameters for wall design. Please note that Geoscience can provide modular block retaining wall design services. Soil test borings should be performed along the centerline of the proposed modular block retaining walls. Additional recommendations with regard to foundation support and subgrade preparation can be provided after the soil test borings are performed. In addition, full time observation and testing must be performed during wail construction and backfill placement. Cut And Fill Slo es: We recommend that all permanent cut slopes within residual soils and properly compacted fill slopes be no steeper than 2'/z(H):I(V). For maintenance purposes, the permanent slopes may need to be flattened to allow access to mowing equipmcnt. The cut and fill slopes must be properly vegetated to minimize erosion. Furthermore, the slopes that are greater than 10 feet in height should have appropriately spaced parallel slope drains on the slope face to help protect it from erosion. Temporary slopes in confined or open excavations should perform satisfactorily at inclinations of I (H):1(V); however, the surface of these slopes should be adequately protected from inclement weather. Also, if soft/saturated soils or groundwater are encountered within the excavations, then flatter slopes, dewatering and/or shoring will likely be required. All excavations should conform to applicable OSHA regulations. For permanent slopes less than 5 feet in height, the future building and pavement limits should be offset a minimum five (5) horizontal feet from the crest of the slope. For permanent slopes that are 5 or more feet in height, the future building and pavement limits should be offset a minimum horizontal distance equal to the slope height. Appropriately sized ditches should run above and parallel to the crest of all permanent slopes to divert surface runoff away from the slope face. Fiorenza Properties, LLC Geoscience Project No. CH22.002 LGE March 31, 2022 Page 6 To aid in obtaining proper compaction on the slope face, all fill slopes must be overbuilt with properly compacted structural fill and then excavated back to the proposed grades. Traversing the slope face with a bull dozer does not constitute proper compaction of the slope face. Also, any fill placed in sloping areas must be properly benched into the adjacent soils. Detention Pond: A detention pond is proposed for the southeastern portion of the site. Soil test borings B-10 and B-I I were performed within the general area of the detention pond. Based on the absence of groundwater, our visual classification of the soil samples and the moisture conditions of the soil samples, the Seasonal High Groundwater Table (SHWT) at the location of borings B-10 and B-11 is estimated to be below 674 and 683 feet (MSL), respectively. If the pond is required to hold water, it may be necessary to over -excavate the pond and install a soil liner consisting of the near -surface very clayey soils with a minimum thickness of 2 feet. The excavation area should include the pond bottom and sidewalls up to the permanent pool elevation. PROJECT CONSTRUCTION Site Qmdding Considerations: Residual very silty CLAY and very clayey SILT soils were encountered near the ground surface in soil test borings B-1, B-2, B-4, B-5, B-8, B-10 and B-11. Based on the Standard Penetration Test results, our visual classification of the soil samples and the laboratory test results, these soils have a stiff to very stiff consistency and generally appear suitable for direct foundation, floor slab and pavement support. However, these near -surface very clayey soils are susceptible to moisture intrusion and can easily become remolded (i.e. softened) under the weight of repeated construction traffic. Consequently, some undercutting of these soils could be required; the extent of the necessary undercutting will be influenced by the weather conditions, the time of year during which site grading is performed and the amount of construction traffic that passes over these very clayey soils. A qualified geotechnical engineer from our office can make the appropriate recommendations for handling these very silty CLAY and very clayey SILT soils during construction once the site conditions become more apparent. The results of our laboratory testing program indicate that the onsite soils are suitable for use as structural fill. However, it should be noted that most soils within the anticipated excavation depths are fine-grained with elevated moisture contents. These soils will require good technique on the part of the grading contractor in order to achieve proper compaction. In addition, these materials can be difficult to work even under favorable conditions, and attempting to compact these soils during a wet period of the year may be very difficult. Additional recommendations in this regard are outlined below in the Fill Material And Placement section of this report. Although not encountered in any of the soil test borings, alluvial soils may be present in the vicinity of the drainage features that extend across the northeastern and southeastern portions of the site. Alluvial soils are typically unsuitable for direct support of any buildings, Fiorenza Properties, LLC Geoscience Project No. CH22.002LGE March 31, 2022 Page 7 pavements, storm pipes and/or structural fill soils. Therefore, any alluvial soils encountered during site construction should be undercut and replaced with properly compacted structural fill. Further recommendations in this regard should be provided in the field by a qualified geotechnical engineer from our office once the site conditions have been revealed during construction. Site Preparation: The proposed construction area should be stripped of all topsoil, organic material and other soft or unsuitable material. In addition, any utilities encountered within the proposed construction Iimits should be properly relocated, as required, and the resulting excavations backfilled with suitable fill material. Any other isolated excavations should also be backfilled with properly compacted structural fill. Upon completion of the above preparatory operations, the exposed subgrade in areas to receive fill should be compacted with an adequately sized roller and proofroIled with a loaded dump truck or similar pneumatic -tired vehicle having a loaded weight of approximately 25 tons. After excavation, the exposed subgrade in cut areas should be similarly compacted and proofrolled. All proofrolling operations should be performed under the observation of a geotechnical engineer or his authorized representative from Geoscience. The proofrolling should consist of two (2) complete passes of the exposed areas, with each pass being in a direction perpendicular to the preceding one. Any areas which deflect, nut or pump during the proofrolling, and fail to be remedied with successive passes, should be undercut to suitable soils and backfilled with properly compacted structural fill. However, within the deeper fill zones, any unsuitable materials could probably be compacted in -place and/or bridged through the planned grading operations. Bridging may include the use of geogrid, geotextile and/or select stone fill. The decision to undercut or bridge any soft or unsuitable areas should be made in the field by an engineer from our office once the site conditions have been revealed during construction. Areas of the project site that are pre -graded for construction should be positively sloped to facilitate surface drainage. In addition, these areas of the project site should be seeded as a precaution to protect the near -surface soils from inclement weather and erosion. The passage of time can adversely affect pre -graded areas, requiring them to be re -worked prior to construction. Groundwater: No measurable groundwater was observed in any of the soil test borings performed for this phase of the project. At this time, it does not appear that permanent dewatering will be required beneath the buildings and pavements. However, Geoscience should review the final site grades to determine if recommendations with regard to permanent dewatering are required. Construction problems related to groundwater could be encountered during site grading in the vicinity of the existing drainage features. Generally, the groundwater associated with these areas of the site, if encountered during grading, could probably be controlled through the use Fiorenza Properties, LLC Geoscience Project No. CH22.002LGE March 31, 2022 Page 8 of sump areas, closed conduits (pipes), diversion trenches and/or filtered trench drains that discharge to suitable outlet areas. Additional groundwater problems, if encountered, should be addressed in the field by a qualified geotechnical engineer as they occur. Difficult Excavation: The results of our subsurface exploration indicate that the majority of the onsite soils can be excavated with conventional construction equipment. However, partially weathered rock was initially encountered in soil test borings B-3, B-11 and B-12 at depths ranging from approximately 3 to 8 feet below the ground surface. In addition, it should be noted that subsurface conditions in the Piedmont can vary drastically over short distances and dense materials and conditions such as boulders, rock lenses, partially weathered rock and mass rock may be encountered between the boring locations. For partially weathered rock encountered above the finished grades, a D-8 or similar size dozer equipped with a steel tooth ripper may be required to loosen these materials prior to their removal. In addition, for removal of dense soils and partially weathered rock within deep utility and other confined excavations, a Caterpillar 335 or similar size backhoe equipped with rock teeth may be required. Also, some blasting or other rock excavation techniques may be required to remove very hard or very dense materials, particularly within deep utility trenches and the lift station excavation. If blasting is required, we recommend that it be performed by a qualified blasting contractor prior to the start of building construction. Once detailed grading and utility plans are developed, consideration should be given to further exploring the presence of very dense materials and rock in the deeper excavation areas of the site. The additional field services should include test pit excavations and/or auger probe borings. Fill Material and Placement: All fill used for the project should be free of organic matter and debris with a low to moderate plasticity. The fill should exhibit a maximum dry density of at least 90 pounds per cubic foot, as determined by a Standard Proctor compaction test (ASTM D 698). We recommend that moisture control limits of +2 to -2 percent of the optimum moisture content be used for optimum placement of project fill. In addition, any fill soils placed wet of the optimum moisture content must remain stable under heavy pneumatic -tired construction traffic. The onsite residual soils generally appear suitable for use as structural fill, provided they are placed at the appropriate moisture content. However, due to the plasticity characteristics associated with the very silty CLAY and very clayey SILT soils, difficulties will likely be encountered while attempting to dry and place these materials as properly compacted structural fill. The natural moisture content determinations performed for this project indicate moisture contents of the residual soils ranging from approximately 15%2 to 51 percent. Based on our visual classification of the soil samples, the laboratory test results and our area experience, the in -situ moisture contents of the majority of the residual soils are slightly below to moderately above their estimated optimum moisture contents. Therefore, some moisture modification of the onsite soils, particularly drying, will likely be required prior to their Fiorenza Properties, LLC Geoscience Project No. C1122.002LGE March 31, 2022 Page 9 placement as structural fill. Project construction during the hotter summer months will help reduce the difficulties and time associated with drying the onsite soils to an acceptable moisture content. Thinner fill lifts, utilizing a disc harrow on each fill lift and/or lime treatment are methods to help reduce the drying time of these soils if the moisture contents are or become significantly higher than the optimum moisture content. The onsite soils are susceptible to moisture intrusion. The site grading contractor should limit the amount of moisture intrusion into these soils by maintaining positive drainage during fill placement and sealing off the exposed subgrades with pneumatic -tired vehicles or smooth drum rollers prior to a rainfall event. Despite these efforts, drying of the exposed subgrades will likely be required after significant rainfall events. If the time required to dry these soils to an acceptable moisture content is not conducive to the construction schedule and/or site grading occurs during cold and inclement weather, then consideration could be given to using lime as a drying agent. The method and rate of application is important to the success of this process. The best method for mixing is to use a reclaimer with a spreader box. However, it is also possible to till the lime into the soils with an appropriately sized disc harrow. A smooth drum roller should be onsite to seal off the lifts of the lime treated soils. For drying of the soils, we are anticipating an application rate of 3 to 4 percent of the soil's dry unit weight. However, the use of lime is not an exact science; .._.., .�.. n process and application iatG may need to be adjusted during the job as the weather dictates. An effective mixing process and application rate can be determined through laboratory tests and field trials at the start of construction with adjustments made as needed during site grading. All fill should be placed in lifts not exceeding twelve (12) inches loose thickness and should be compacted to at least 95 percent of its Standard Proctor maximum dry density. In addition, for isolated excavations, a hand tamper or walk -behind roller will likely be required. While using a hand tamper or walk behind roller, the maximum lift thickness (loose) should not exceed five (5) inches. We recommend that field density tests be performed on the fill as it is being placed, at a frequency determined by an experienced geotechnical engineer, to verify that proper compaction is achieved. Footing Observations: We recommend that the footing excavations be observed by an experienced geotechn ical engineer or authorized representative to verify that suitable soils are present at the proposed bearing elevation. In addition, a footing observation program involving hand auger borings with Dynamic Cone Penetrometer testing should be performed within the footing excavations to confirm the suitability of the underlying soils. If soft or unsuitable materials are encountered, they should be undercut and replaced with select materials suitable for the design bearing pressure. Bearing surfaces for foundations should not be disturbed or left exposed during inclement weather; saturation of the onsite soils can cause a loss of strength and increased compressibility. If construction occurs during inclement weather, and concreting of the Fiorenza Properties, LLC Geoscience Project No. CH22.002LGE March 31, 2022 Page 10 Consulting Engineers foundation is not possible at the time it is excavated, a layer of lean concrete should be placed GEOSC1ENCE on the bearing surface for protection. Also, concrete should not be placed on frozen GROUP subgrades. CLOSURE Geoscience appreciates having had the opportunity to assist you during this phase of the project. If `mMyfiFF/ questions concerning this report, please contact us. CA �P� Respe�F�E S Si::.�i��� :a S t William''!�j Senior Eng I I I \ North Carolina Lic a No. 46603 Daniel A. Mickney, P.E Senior Vice President North Carolina Licens o. 24977 Enclosures j File: P:/Wmt Files/Ge&v-- 202V0021 McCanless Road SubdivisioWgwtw1rdcal report.doc APPENDIX Boring Location Diagram Generalized Subsurface Profiles Investigative Procedures Test Boring Records I- .. -GNO B-1 r Y B 3 � r a r B-6 A + a B 10: I ... MCCANLESS ROAD SUBDIVISION PRELIMI SALISBURY, NORTH CAROLINA 4 8-12}— BORING LOCATION DIAGRAM DRAWING NO. CH22.0021.GE-1 r GEPOSCIENCE APPROXIMATE SCALE; 1' = 200' APPROXIMATE BORING LOCATION i } ;l ti ' GROUP 4 ` 500-K Clanton R cl 1 - i Charlotte, NC 28217 S 11 ` i4 Phone:704.52S.2oo3 Fax: 704.525.2051 S i 1 www.9eoscieixegroup.cam L- Jce) W ti ° O CD Cl) m W m O O Lq O •• m z C9 10 o 0) co m� ��. 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INVESTIGATIVE PROCEDURES McCanless Road Subdivision Geoscience Project No. CH22.0021.GE Page 1 Of 1 FIELD Soil Test Borings: Twelve (12) soil test borings (B-1 through B-12) were drilled at the approximate locations shown on the attached Boring Location Diagram, Drawing No. CH22.0021.GE-1. Soil sampling and penetration testing were performed in accordance with ASTM D 1586-84. The borings were advanced with hollow -stem, continuous -flight augers and, at standard intervals, soil samples were obtained with a standard 1.4-inch (3.6cm) I.D., 2-inch (5.1cm) Q.D., split -tube sampler. The sampler was first seated 6 inches (15.2cm) to penetrate any loose cuttings, then driven an additional 12 inches (30.5cm) with blows of a 140-pound (63.5kg) hammer falling 30 inches (76.2cm). The number of hammer blows required to drive the sampler the final 12 inches (30.5cm) was recorded and is designated the "Standard Penetration Resistance" (N-Value). The Standard Penetration Resistance, when properly evaluated, is an index to soil strength, density and ability to support foundations. Representative portions of each soil sample were placed in sealed containers and taken to our laboratory. The samples were then examined by an engineer to verify the driller's field classifications. Test Boring Records are attached indicating the soil descriptions and Standard Penetration Resistances. LABORATORY Moisture Content: The moisture content is the ratio, expressed as a percentage, of the weight of the water in a given mass of soil to the weight of the solid particles. This test was conducted in accordance with ASTM Designation D 2216-66. The test results are presented on the applicable Test Boring Records. Soil Plasticity Test Atterberg Limits Test: Representative samples of the near -surface soils were obtained to determine the soil's plasticity characteristics. The Plasticity Index (PI) is representative of this characteristic and is bracketed by the Liquid Limit (LL) and the Plastic Limit (PL). The Liquid Limit is the moisture content at which the soil will flow as a heavy viscous fluid and is determined in accordance with ASTM D 423. The Plastic Limit is the moisture content at which the soil begins to lose its plasticity and is determined in accordance with ASTM D 424. The data obtained is presented on the applicable Test Boring Records. ,22 JCi#3IVO, CA1.GE _ T...RECAM RMPi INC. DEPTH, FT. DESCRIPTION 0.0 Elegy. Moisture 732.0f Content Blow • PENETRATION - BLOW COUNT* Count 5 10 20 30 40 $0 80 100 0.5 Topsoil And Roots 731.5 Stiff Reddish -Brown And Tan Slightly Micaceous Medium To Fine Sandy Very Silty CLAY - Residual LL = 791131- = 321PI = 47 35.2% 12 Note: Sample Moist 3.0 729.0 Stiff Reddish -Brown And Tan Slightly Micaceous Clayey Medium To Fine Sandy SILT Note: Sample Very Moist 38 51/0 9 5.5 726.5 Stiff Brown And Tan Slightly Micaceous Medium To Fine Very Sandy SILT 25.7°k 11 8.0 724.0 Firm Tan And Grey Slightly Micaceous Silty Medium To Fine SAND 10.0 —------------------ 722.0 16 Borin—g Terminated No Groundwater Encountered >3OEnG AND SA MPUNG MEEIS MTX D-1516 �_A* PPER&S RnaltR 11011' MAT= TAUS - 24 HE CORE DWI MG MEETS AM M D4113 1501% ROCK COMFRW01, it V — _= -AA1PIt 1'14131C.1i; -1 HR. - FENMR&_T10N IB TflK -NLMBE K bF SLOWS OF.4 14g LB. (43.sLg) 4 IA36S Of DRnJ NG V4 A nR ON i CAVE4N DM H HaL'lrWR FU I ING W IN (76.km) RE44L,IRED 110 DR[R E A 14 IN. WOR i Iffiftr Cam`HA'1Il4 ER PACT, 1 of 1 .f3.6em1 M SA.'41PLPR 1 IT. 00 5cm1 iiaR3-�iTEST 2 _ _ _. MnUWiCaMaC-I(W tt �. — BANG GEOSCIENCE .N.c _��, DEPTH, FT. DESCRIPTION 0.0 Elev. Moisture 727.0± Content Blow 0 PENETRATION - BLOW COUNT* Count 5 10 20 30 40 BO 80 100 0.5 Topsoil And Roots 726.5 Stiff Reddish -Brown And Tan Slightly Micaceous Medium To Fine Sandy Very Clayey SILT - Residual Note: Sample Moist 36.6'/6 12 3.0 724.0 Stiff Reddish -Brown And Tan Slightly Micaceous Clayey Medium To Fine Sandy SILT Note: Sample Very Moist 39.4% 11 5.5 721.5 Firm And Stiff Reddish -Brown, Tan And Black Medium To Fine Sandy SILT Note: Samples Very Moist 42.6% 10 10.0 -------------------- 717.0 39.1% 8 Boring Terminated No Groundwater Encountered IIRiRiNG AAiD I U4iPLI G T _4 D-15�6 �(+ I9�7 = ►UIPATABU - 24 HR COW DRILLING Nn%"rB ASTM D4113 �30�°:o ROC:E C'O]li1P.-RBRY —_ V4a'IER T?BLIv -1 iIR, S'P 'kF TRAI IO V 11s 7'III.'�171±[Si� GF Bf.OR ; o>< .11A0 L B_ (�3.511tgj 1 OF DRll1 .tiG wATF'R ON j C to FAN DEPTH HQ*1MFR FAL 1 NG 30 IN. (7&UM) RLQGTRED '11D DRI1 L A 1A IN. %10H WEIGH1 Of HAWMA*R Q3AUW LM !�MM 1 FAT. (Wkw) PAGE of I J K)B NO.~ CIM t 096E DEPTH, FT 0.0 0. 91 10.1 DESCRIPTION Elev. 7'3Q n+ IEEST RING GEOSCIENCE RECORD GROUP, INC. Blow 0 PENETRATION - BLOW COUNT* 5 Topsoil And Roots 722.5 55 78 79 5010.4 Very Dense Brown And Grey Silty Coarse To Fine SAND With Rock Fragments - Residual i 717.5 Very Dense Brown And Tan Silty Medium To Fine SAND f 715.0 Partially Weathered Rock When Sampled Becomes Tan And Grey Silty Medium To Fine SAND I-------------------- 713.0 Boring Terminated No Groundwater Encountered I i BOMNG AND SAMPILW M LTh " M D-IS86 Pmawmmx r=T CORE DRR NG N1FEI S ASIM D-2113 150$ WCK CORD Rili MV'RRY `PEhE'iRA ON IS THE 11UAIBER OP BLOWN OF, A 140 LB. (63 SkV , L(*, OF )DRI LING R ATUR C.ALVF N iiDMH H ILMN1ER F ALUNG 30 IN. (76.2cm) REQLIRL D To DRn B A. JA 1N WC-H W KIWIT Of $+ MMLR PAGE � Of I'I1�IPi IT. 0 rq.. DATEDM1LD. n � . __ �..�_. _ TENT DEPTH, FT. DESCRIPTION 0.0 Elev. Moisture 715.0± Content Blow 0 PENETRATION - BLOW COUNT* Count 5 10 20 30 40 60 80 100 0.6 Topsoil And Roots 714.4 Stiff Reddish -Brown, Tan And Black Medium To Fine Sandy Very Silty CLAY - Residual 22.8% 10 40 LL = 521PL = 221PI = 30 3.0 712.0 Very Stiff Reddish -Brown And Tan Clayey Medium To Fine Sandy SILT Note: Sample Moist 37.3% 20 6.0 709.0 Stiff Reddish -Brown And Tan Clayey Medium To Fine Sandy SILT Note: Sample Very Moist 50.9% 10 8.0 707.0 Firm Reddish -Brown And Tan Medium To Fine Sandy SILT Note: Sample Very Moist 10.0 ------------ —o—ring 705.0 6 T---ermin---ated B No Groundwater Encountered I i BORING.AND &AWIFI lG 1l4E T& AH M 0-15a ,s_V PREssLREMET16,R TEgr = w4TER fAK.E - 24 E[FL CORE DRU UNG MMET& A51 M D-2113 150 ,; Rom ICoRr aEcovERY =y` '%VAIN 1'.UBI,LC -1 HR *PENETR41ION IN'THE NLIIBER Or BLOWS Of A 140 LB (63.5i g) 4 L(AS (*' DRHJXNG WAIER � � c:At�IN IItEPTH H4MNIM FAILING 30 LAC. {76.2rm) RriQUIRTyD T O DRIAT A 1A 1N ��'ivif lii OF SA�41fl1lER �_Q 6CM1 LD- 5"IPLER I r'r._(30.Scm] PAGE 1 Of 1 � TEST _)VICANLM ROAD DEPTH, FT 0.0 0.5 Top 3. 5.' 10.1 DESCRIPTION Elegy. Moisture Blow 771 A+ t,-- & • PENETRATION - BLOW COUNT* 5 10 20 30 40 60 80 100 soil And Roots 720.5 30.0% 26.1 �,� 28.0% 19 18 10 9 Very Stiff Reddish -Brown And Tan Medium To Fine Sandy Very Clayey SILT - Residual 718.0 Very Stiff Reddish -Brown And Tan Clayey Medium To Fine Sandy SILT i 715.5 Stiff Reddish -Brown And Tan Medium To Fine Sandy SILT -------------------- Boring Terminated No Groundwater Encountered 1 711.0 10 13ORYNG VID i4.iAi LLNG MELTS AWM, D-I86 WATER rABLE - 24 E[I9L CORE DFJItJNGMLETS 4Snl"113 150K I ('URLRI.C`L34EIi ' __,- Wkn$tT4TJLE. t HR. ° METR UION I5 THE NID IM OF BLOB-+ Or It 1401•1L t63-%W 4 L0M OF" DRRflA JN G %A` XR 1 C-,kA &L410EP'IH HAMMER I? UJ NG 30 IN (7&2LM) RFAULHti.D TO DR18 E 4,14 IN woHIGHT OF HAMMER ID &AMPS I r-r. ��i 'V4 EFAGS, 1 Qfj BORVO NO M_. _ _ _ _ .� ._ TAT NO ' 9W:_1 1.M _ - — RECORD PRwwr GROUP, INC. DEPTH, FT. DESCRIPTION 0.0 Elev. Moisture 721.0f Content Blow PENETRATION - BLOW COUNT* Count 5 10 20 30 40 60 Bo lop Topsoil And Roots 1.0 720.0 Stiff Reddish -Brown, Tan And Black Medium To Fine Sandy SILT - Residual 30•9% 11 10 Note: Sample Moist 3.0 718.0 Very Stiff Brown And Tan Medium To Fine Very Sandy SILT 15.7% 16 5.5 715.5 Firm Brown And Tan Very Silty Medium To Fine SAND 13 18 10.0 -------------------- 711.0 Boring Terminated No Groundwater Encountered NOWNG ANI1 &A1nLNG "AWM D-1S88 PRTAR nw ivAuk iABLE - 24 WL COS DRILLING Rt M "5 Abr I M D-2113 Is+% C0ftRLC10rY1ltft —_- NrATERr.+Rt.S-11M *PLNUMATION IS'=, NUAM t OF BLOWS Or A 140 LB (63 5kg) 4111 L S'& cam' DPM 1R iG'WAIi$ on 1 C-+,tr--rN DBP'IH HXNLMLLR F ULLING 30 Li. (7,6.Zcm) RFQI,IRL D TO IiME A 1A IN. %oH ES Eican OF HAllN11A1ER ,J%6c� LD. &All�1 LER 1_Pi (39,aem) PLACE .BiMMNf 3 9-1 DArE DRul-ED 3QIA NO. CHUM169 p DEPTH, FT. DESCRIPTION 0.0 0.61 Topsoil And Roots Very Stiff Brown And Tan Medium To Fine Sandy To Very Sandy SILT - Residual --------------------- boring Terminated No Groundwater Encountered 1"T BORING GEOSCIENCE RECORD GROUP, INC. Elev. Moisture Blow • PENETRATION - BLOW COUNT* 20•1% 1 21 17.7% 1 20 17.8% 1 24 BORING .AND 8AMPLLNG N0l%Th "IM WIS@6 CORE DRLI.LL_NG hi> E18 AS rM D-2113 "PE\ A11 i--V IS 1HL NLMBER OP BUM 5 OF A 140 i K (63.51g) RALMWR FAI I-ING 301N. (76.3eni) iRFQGIRL;D 710 DRIVE A 1A IN 29 :� PRE55iPAE itR7i 4I - � WAIM r4RX-UFO ROCK COPS IIICO nM — WAILR' 411111Ii: - i EUL A L060i O DRILLING %ATER 00 j CAVF M DFPIB WGH N% IGHT OF HAMMPR PAGE 1 of 1 PORWO NO RECORD GRIP, INC. DEPTH, FT. DESCRIPTION 0.0 Elev. Moisture 713,0± Content Blow 0 PENETRATION - BLOW COUNT* Count 5 10 20 30 40 60 60 100 0.5 Topsoil And Roots 712.5 Stiff Reddish -Brown And Tan Slightly Micaceous Medium To Fine Sandy Very Clayey SILT - Residual 34.1% 11 Note: Sample Moist 3.0 710.0 Stiff Reddish -Brown And Tan Slightly Micaceous Medium To Fine Sandy SILT Note: Samples Moist 35.5% 9 9 8.0 706.0 Very Stiff Reddish -Brown, Tan And Black Slightly Micaceous Medium To Fine Sandy SILT" 16 10.0 -------------------- 703.0 Boring Terminated No Groundwater Encountered R0FjNG AND i 4V' PL VfG ME'EU .4YM D-1586 PRL%UR1Mr=1FS1r TAAIER TABLC . 24 ML CORL DRD.C.ING MELT S .ASTM D-2113 :A CORE RFiXA MY == V! 41f R rABLL - I EljL +IPL`NETAiXION 18 T= NUNIBIR OF BLOV4S Or i-146 LB (63AW 4 L(M OF DRIUANG WAT81t s f:AVF-LN D1P1111 R %,MAZR i iL LING 30 M (76 24 M) REQUIRED TO DRIN-F. A ] A 1N. woK iNEiGn r of RAmvim WdWMILD FS:tw' LER 1 I".I ap.Sew P:11.GF' 1 Of 1...,. _ J 4CY_ IAIP DRIIUD3i��__ TEST JOB NC) clla.ieoz.�— _ RED GROUP PRQJE�C°>� .�I� - ����.��'�SI�k� _.,., , INC. DEPTH, FT. DESCRIPTION Elev. Moisture Blow 0 PENETRATION - BLOW COUNT* 0.0 717.0± Content Count 5 10 20 30 40 60 80 100 0.5 Topsoil And Roots 716.5 38.1% 18 40 714.0 17.9% 21 711.5 17.a3b 19 707.0 26 Very Stiff Reddish -Brown, Tan And Black Medium To Fine Sandy Clayey SILT - Residual Note: Sample Very Moist 3.0 Very Stiff Reddish -Brown And Tan Medium To Fine Sandy SILT 5.5 Very Stiff Brown, Tan And Grey Medium To Fine Sandy SILT 10.0— — — — — — — — — — — — — — — — — — — — Boring Terminated No Groundwater Encountered BOWNG 51�0 5AMPUNG MKF I S WIM 13-M 6 [WO PRmuwAnEkira 'V14T1ER TABU; - 24 HB. C (W- DR1L,1-F%G MMU ASTNl D 2113 150K R0Ck RKXn M' = wa.JERTABU -1 Imo. *PKVE'.FRAT 10N 75113i+ i U.M BER OF BLOR-s OF. k la0 l & (63-%t i LtiS of DkRII um. v4,'lTm cime.-4Nt iDma HAMUFR F %LUNG 30 LET. (76.2an) RLQUHUR D TO DRINT A 1A EN. wox v% EIGH'T of n iLNmR 3. PAGE 9 Of BORING NO -------�— --- DA> E MLEV. ._ TEST DR1UJN(JC-M1RACT0R ._ EWING GEGSCIENCE JM NO. QIZZ.0021 G _— YXisn'. RECORD SUP, INC. DEPTH, FT. DESCRIPTION Elev. Moisture Blow 0 PENETRATION - BLOW COUNT* 21 0.0 694.0± Content Count 5 10 20 30 40 60 80 100 0.5 Topsoil And Roots 693.5 Stiff Reddish -Brown And Tan Medium To Fine Sandy Very Clayey SILT With Fine Roots - Residual 38.3% 12 Note: Sample Very Moist 3.0 691.0 Very Stiff Reddish -Brown And Tan Clayey Medium To Fine Sandy SILT 29.9% 18 5.5 688.5 Very Stiff Brown And Tan Medium To Fine Sandy SILT 15.4% 22 21 2.0 682.0 Very Stiff Brown, Tan And Grey Medium To Fine Very Sandy SILT 26 41 1.0 674.0 27 i Boring Terminated No Groundwater Encountered BORING AND SAWLINCr.NIEFr8 4kSTMD-1386 C'ORr, DR 1.LING ?#1E TS 4& 1Ni D-2113 ' PENVIR.kI ION IS 7 HE NUMBER OF BLOWSY OF A 140 LB. (vb kfflo S.V%IMERP'.ALIJJ IG 30IN (76 200 RkQUIRED'IO DR" E A 1.4 IlY. PRd9Sumwm InI' = Wvm mw.,E-IAnl I50I1,, RAIL Ci?DE RltCd't+'ERY '%VA.TER T'kBLE -1 ffit. 44 1 OF DRI1.LRG %ATER IM I C.4t IN Dmu WOO 11UGHI` 0P-11AMMER Pik a(•;L 9 Of 1 D A:IE, IM F.D 311"_ _ - _ - . ` TEST -�,..�.��..,- RECORD GROUP, INC. ,pRowrr DEPTH, FT. DESCRIPTION Elegy. Moisture Blow 0 PENETRATION - BLOW COUNT* 2( 0.0 703.0± Content Count s 10 zo 30 40 60 80 100 0 6 Topsoil And Roots 702.4 Very Stiff Brown And Tan Medium To Fine Sandy Very Clayey SILT With Fine Roots - Residual W6% 16 Note: Sample Moist 3.0 700.0 Very Stiff Brown And Tan Medium To Fine Sandy SILT 18.1% 21 5.5 697.5 Dense Tan And Grey Silty Medium To Fine SAND 46 8.0 695.0 Partially Weathered Rock When Sampled Becomes Brown, Tan, Grey And White Silty Medium To Fine SAND 5010.4 5010.3 • 0 686.0 Partially Weathered Rock When Sampled Becomes Tan And Grey Silty Coarse To Fine SAND 5010.4 1.0 — — — — — — — — — — — — — — — — — — — — 683.0 Boring Terminated No Groundwater Encountered HORING.&NDS4N.i)p')T..t1G.NIIECIS.UTil D-1-486 CORE DRR-IJI rG TS ASP! W21I3 `WNETRA1ION Ib �rrtrrff NUMBIR OF BLO` kN Of' 1140 iB. (63.5W H4N"I rR FAI ZING 3411. (76.2cm) REQVIRLD TO DRn L A 14 IN. MT R ATF,R TAKX - 24 HR 15+RICX X t 0n REC0 V%.RY WATER IABLE -1 MR Lo%orDRILI rNG %A,IRR jW j C,kjT L r*EPIH WM WEIGH rO HAILMER PAGE DM���_ - W_ TEST DRUL cjQN-'.(1 . _ BOMNG GEOSClENCE KM NO C1W.ft21.GF,REWRD GROUP, INC. 0JWr N1eCA)d&&4" MM-MMQA DEPTH, FT. DESCRIPTION Elev. Blow 0.0 706.0± Courn Topsoil And Roots 1.0 705.0 Very Dense Tan And Grey Silty Coarse To 67 Fine SAND With Clay Seams - Residual 5.5 12 17.0 20.0 Partially Weathered Rock When Sampled Becomes Tan And Grey Silty Coarse To Fine SAND With Rock Fragments 60/0.3 Partially Weathered Rock When Sampled Becomes Brown, Tan And Grey Silty Coarse To Fine SAND With Rock Fragments 50/0.4 Partially Weathered Rock When Sampled Becomes Tan And Grey Silty Coarse To Fine SAND With Rock Fragments Partially Weathered Rock - No Sample Recovery --------------------- Boring Terminated No Groundwater Encountered 50/0.4 50/0.4 50/0.3 • PENETRATION - BLOW COUNT* DURING ANI) SAWLING MI E1S ARM D-1M6�IJR i M TM= VI ��ER T �DLTc - 24 OII. CORE DIUUJNG 1IF-En AS]'143 D 2113 15ok. RwKcORF. trxovm - WATER7ABLF.-1ML -I'LNETRAI ION IS THE NUMBIA OF BL0%S OF.A 140 LB. (63 MW 14 L41398OF DRIULVG AME;R ON I C-ti, I? IN DFP7H H�i11 P-%LIJNG 30 M. (76. 2CO REQUIRED TO DIN F. A 14 IN WOH ULT(M OF HAMMER. A IER c PAGE 12f 9