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HomeMy WebLinkAboutSW3210701_Soils/Geotechnical Report_20210913SUMMIT ENGINEERING . LABORATORY • TESTING REPORT OF GEOTECHNICAL SUBSURFACE EXPLORATION FLOWES STORE ROAD 10714 FLOWES STORE ROAD MIDLAND, NORTH CAROLINA SUMMIT PROJECT NO. 0109.G0024 Prepared For: Mr. Matt Kearns Shea Homes 8008 Corporate Center Drive, Suite 300 Charlotte, North Carolina 28226 Email: Matt.kearnsnsheahomes.com Prepared By: SUMMIT Engineering, Laboratory & Testing, P. C. (SUMMIT) 3575 Centre Circle Drive Fort Mill, South Carolina 29715 August 28, 2020 ENGINEERING • LABORATORY • TESTING 3575 Centre Circle Drive I Fort Mill, South Carolina 29715 1 (704) 504 - 1717 1 (704) 504 - 1125 (Fax) WWW. SU M M IT-COMPAN I ES. COM IAA� SUMMIT ENGINEERING . LABORATORY. TESTING August 28, 2020 Mr. Matt Kearns Shea Homes 8008 Corporate Center Drive, Suite 300 Charlotte, North Carolina 28226 Email: Niatt.ke�irnti Ciislieahonies.corn Subject: Report of Geotechnical Subsurface Exploration Flowes Store Road 10714 Flowes Store Road Midland, North Carolina SUMMIT Project No. 0109.G0024 Dear Mr. Kearns: SUMMIT Engineering, Laboratory & Testing, P. C. (SUMMIT) has completed a geotechnical subsurface exploration for the subject project located at 10714 Flowes Store Road in Midland, North Carolina. This subsurface exploration was performed in general accordance with our Proposal No. 0109.G0024 dated August 15, 2020. This report contains a brief description of the project information provided to us, general site and subsurface conditions revealed during our geotechnical subsurface exploration and our general recommendations regarding foundation design and construction. SUMMIT appreciates the opportunity to be of service to you on this project. If you have any questions concerning the information presented herein or if we can be of further assistance, please feel free to call us at (704) 504-1717. Sincerely yours, SUMMIT Engineering, Laboratory & Testing, P. C Todd A. Costner, E.I. Senior Professional CA s� unnn�lo = Engineering, ' Laboratory & ` m : Testing, P.C. c� C-4361 r� Richard J. Eller, Jr. P.E. Principal Engineer Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 TABLE OF CONTENTS SECTION Page EXECUTIVE SUMMARY........................................................................................................... ill 1.0 INTRODUCTION.............................................................................................................. I I.I. Site and Project Description.................................................................................... 1 1.2. Purpose of Subsurface Exploration......................................................................... 2 2.0 EXPLORATION PROCEDURES...................................................................................... 3 2.1. Field Exploration.................................................................................................... 3 3.0 AREA GEOLOGY AND SUBSURFACE CONDITIONS ............................................... 4 3.1. Physiography and Area Geology............................................................................ 4 3.2. Generalized Subsurface Stratigraphy...................................................................... 4 3.2.1. Surface Materials........................................................................................ 5 3.2.2. Alluvial Soils.............................................................................................. 5 3.2.3. Existing Fill Soils....................................................................................... 6 3.2.4. Residual Soils............................................................................................. 7 3.2.5. Partially Weathered Rock and Auger Refusal ............................................ 7 3.2.6. Groundwater Level Measurements............................................................ 7 4.0 EVALUATIONS AND RECOMMENDATIONS............................................................. 9 4.1. General....................................................................................................................9 4.2. Shallow Foundation Recommendations................................................................. 9 4.3. Retaining Wall Recommendations (if used)......................................................... 10 4.4. Low to Moderate Plasticity Moisture Sensitive Soils (CL and MH).................... 11 4.5. High Plasticity Moisture Sensitive Soils (CH) ..................................................... 12 4.6. Wet Weather Conditions....................................................................................... 13 4.7. Floor Slabs............................................................................................................ 14 4.8. Pavements Subgrade Preparation.......................................................................... 14 4.9. Cut and Fill Slopes................................................................................................ 15 5.0 CONSTRUCTION CONSIDERATIONS........................................................................ 17 5.1. Abandoned Utilities/Structures............................................................................. 17 5.2. Site Preparation..................................................................................................... 17 5.3. Difficult Excavation.............................................................................................. 18 5.4. Temporary Excavation Stability........................................................................... 20 5.5. Structural Fill........................................................................................................ 20 5.6. Suitability of Excavated Soils for Re-Use............................................................ 22 5.7. Engineering Services During Construction.......................................................... 22 6.0 RELIANCE AND QUALIFICATIONS OF REPORT .................................................... 24 APPENDIX 1 - Figures Site Vicinity Map (Figure 1) Boring Location Plan (Figure 2) APPENDIX 2 - Boring Logs ii Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 EXECUTIVE SUMMARY SUMMIT has completed a geotechnical subsurface exploration for the Flowes Store Road project. A vicinity map showing the project's general location is shown on Figure 1 provided in Appendix 1. The purpose of this exploration was to obtain general information regarding the subsurface conditions and to provide geotechnical recommendations regarding foundation support of the proposed construction. This exploration consisted of thirteen (13) soil test borings (identified as B-1 through B-13). The approximate test locations are shown on Figure 2 provided in Appendix 1. The following geotechnical engineering information was obtained as a result of the soil test borings: • Surface Materials — Surficial organic (topsoil) soils were observed at the existing ground surface of the borings with estimated thicknesses ranging from approximately 2 to 4 inches. • Existing Fill Soils - Existing fill (disturbed) soils were encountered beneath the surface materials in Borings B-10 through B-13 to an approximate depth of 1 foot below the existing ground surface. Please note that these soils were encountered in an open field that may have been once used as an agricultural field (farmland). When sampled, the existing fill soils generally consisted of lean clays (CL) and elastic silts (MH). • Residual Soils - Residual (undisturbed) soils were encountered below the surface materials and/or existing fill soils and extended to either the maximum boring termination depth or partially weathered rock (PWR). These residual soils generally consisted of fat clays (CH), lean clays (CL), elastic silts (MH), sandy silts (ML), and silty sands (SM). The Standard Penetration Resistances (SPT N-values) in the residual soils ranged from 6 to 56 blows per foot (bpf). • Partially Weathered Rock (PWR) and Auger Refusal — Partially weathered rock (PWR) conditions were encountered in Boring B-3 between the approximate depths of 3 to 5.5 and again at approximately 8 feet below the existing ground surface. Auger refusal conditions were encountered in Boring B-3 at an approximate depth of 9.7 feet below the existing ground surface. • Groundwater Levels - At the time of drilling, groundwater was not observed in the borings. • Foundation Support - Based on the results of our borings, the proposed structures can be adequately supported on shallow foundations systems provided site preparation and compacted fill recommendation procedures outlined in this report are implemented concerning unsuitable soils such as alluvial soils, existing fill soils, cultivated soils, and fat clays. An allowable net bearing pressure of up to 2,500 pounds per square foot (psf) can be used for design of the foundations bearing on approved undisturbed residual soils, or on structural fill compacted to at least 95 percent of its Standard Proctor maximum dry density. iii Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 • Special Construction Considerations: Special considerations are warranted concerning alluvial soils, existing fill soils, cultivated soils, and fat clays. Dependent on final grades, the contractor can anticipate that some undercutting and/or foundation extension may be necessary through unsuitable soils if encountered during grading and construction. Should these soils be encountered during the grading and construction activities, these soils should be inspected in the field by a Geotechnical Engineer -of -Record and/or their designee prior to remediation. Additional testing such as test pit excavations and/or hand auger borings may be required in order to further explore these soil conditions, depths and locations. o Alluvial Soils: Even though alluvial (water -deposited) soils were not encountered in the borings, alluvial soils are typically present in or near drainage features, pond bottoms, creeks and in low-lying areas. Alluvial soils are generally loose and/or under -compacted and, as such, are typically unsuitable for supporting the proposed construction. Therefore, remediation may be required wherever alluvial soils are encountered during grading activities. o Existing Fill Soils: At the time of this report, no relevant information (documentations) regarding previous grading activities, prior materials testing, and/or geotechnical engineering services was provided for our review. Borings B-10 through B-13 encountered undocumented fill soils (fill soils not monitored and tested during placement). Undocumented fill poses risks associated with undetected deleterious materials within the fill soils and/or deleterious material at the interface between the fill soils and residual soils. o Cultivated Soils: Borings B-10 through B-13 were performed in an open field that may have been once utilized as an agricultural field (farmland); therefore, these existing fill soils could be classified as cultivated fill soils. Typically, agricultural fields will consist of existing fill soils in the upper 0.5 to 1.5 feet that are classified as cultivated fill soils. Cultivated fill soil is a layer that was plowed and disturbed for agricultural purposes. Cultivated fill soils are not suitable for building and/or pavement support and are not suitable to be re -used as structural fill material due to the organics mixed in the soil. However, if approved by the Geotechnical Engineer of Record, the organic stained soils may be suitable as structural fill material if the organic content in the soil is less than 5 percent by weight and/or blended with non -organic soils to reduce the organic content. o Fat Clams High plasticity and moisture sensitive (fat clays) soils were encountered in Borings B-4 through B-8 to approximate depths of 1 to 3 feet below the existing ground surface. Highly plastic soils can undergo significant changes in volume (shrink/swell behavior) with changes in moisture conditions. These soils typically provide poor subgrade support for pavements and foundations. Please note that the information provided in this executive summary is intended to be a brief overview of project information and recommendations from the geotechnical report. The information in the executive summary should not be used without first reading the geotechnical report in its entirety and the recommendations described therein. iv Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 1.0 INTRODUCTION I.I. Site and Project Description The subject site is located at 10714 Flowes Store Road in Midland, North Carolina. A vicinity map showing the project's general location is shown on Figure 1 provided in Appendix 1. The subject property is approximately 67.8 acres comprised of Cabarrus County Tax Parcel ID Numbers 5525-66-7987 and 5225-96-0923. At the time of our field exploration, the subject site was mostly undeveloped land comprised of wooded areas, open fields, a house, two (2) ponds and small creeks. The Client (Shea Homes) provided SUMMIT a plan sheet titled "Conditional Rezoning Plan", prepared by The John R. McAdams Company, Inc. dated March 18, 2020, that indicated the configurations of the proposed construction planned for this project. Based on the provided information, we understand the project is planned to include residential lots, roadways and underground utilities. At the time of report preparation, SUMMIT had not been provided structural details of the planned construction indicating proposed loads, foundation bearing elevations, or finished floor elevations. For this report, SUMMIT assumed the proposed structures will be supported on a shallow foundation system consisting of spread, strip, and/or combined footings and that wall loads will be on the order of 1 to 3 kips per foot. Also, grading plans were not available at the time of this report and we have assumed that maximum cut/fill depths will be on the order of 1 to 3 feet over the existing ground surface. 1 Report of Geotechnical Subsurface Exploration Flowes Store Road 1.2. Purpose of Subsurface Exploration SUMMIT Project No. 0109.G0024 August 28, 2020 The purpose of this exploration was to obtain general geotechnical information regarding the subsurface conditions and to provide general preliminary recommendations regarding the geotechnical aspects of site preparation and foundation design. This report contains the following items: • General subsurface conditions, • Boring logs and an approximate "Boring Location Plan", • Suitable foundation types, • Allowable bearing pressures for design of shallow foundations, • Anticipated excavation difficulties during site grading and/or utility installation, • Remedial measures to correct unsatisfactory soil conditions during site development, as needed, • Drainage requirements around structures and under floor slabs, as needed, • Construction considerations, • Pavement subgrade support guidelines. 2 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 2.0 EXPLORATION PROCEDURES 2.1. Field Exploration SUMMIT visited the site on August 20 and 21, 2020 and performed a subsurface exploration that consisted of thirteen (13) soil test borings (identified as B-1 through B-13). The approximate locations of the borings are shown on the Figure 2 - "Boring Location Plan" provided in Appendix 1. The borings were located by professionals from our office using the provided plan, recreation - grade handheld GPS, existing topography, and aerial maps as reference. Since the boring locations were not surveyed, the location of the borings should be considered approximate. The soil test borings were performed using an ATV -mounted CME 550X drill rig and extended to approximate depths of 9.7 and 15 feet below the existing ground surface. Hollow -stem, continuous flight auger drilling techniques were used to advance the borings into the ground. Standard Penetration Tests (SPT) were performed within the mechanical borings at designated intervals in general accordance with ASTM D 1586. The SPT "N" value represents the number of blows required to drive a split -barrel sampler 12 inches with a 140-pound hammer falling from a height of 30 inches. When properly evaluated, the SPT results can be used as an index for estimating soil strength and density. In conjunction with the penetration testing, representative soil samples were obtained from each test location and returned to our laboratory for visual classification in general accordance with ASTM D 2488. Water level measurements were attempted at the termination of drilling. The results of these tests are presented on the individual boring logs provided in Appendix 2 at the respective test depth. 3 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 3.0 AREA GEOLOGY AND SUBSURFACE CONDITIONS 3.1. Physiography and Area Geology The subject property is located in Midland, North Carolina, which is located in the south central Piedmont Physiographic Province. The Piedmont Province generally consists of well-rounded hills and ridges which are dissected by a well -developed system of draws and streams. The Piedmont Province is predominantly underlain by metamorphic rock (formed by heat, pressure and/or chemical action) and igneous rock (formed directly from molten material) which were initially formed during the Precambrian and Paleozoic eras. The volcanic and sedimentary rocks deposited in the Piedmont Province during the Precambrian era were the host of the metamorphism and were generally changed to gneiss and schist. The more recent Paleozoic era had periods of igneous emplacement, with episodes of regional metamorphism resulting in the majority of the rock types seen today. The topographic relief found throughout the Piedmont Province has developed from differential weathering of theses igneous and metamorphic rock formations. Ridges developed along the more easily weathered and erodible rock. Because of the continued chemical and physical weathering, the rocks in the Piedmont Province are generally covered with a mantle of soil that has weathered in -place from the parent bedrock below. These soils have variable thicknesses and are referred to as residual soils, as they are the result of in -place weathering. Residual soils are typically fine- grained and have a higher clay content near the ground surface because of the advanced weathering. Similarly, residual soils typically become more coarse -grained with increasing depth because of decreased weathering. As weathering decreases with depth, residual soils generally retain the overall appearance, texture, gradation and foliations of their parent rock. 3.2. Generalized Subsurface Stratigraphy General subsurface conditions observed during our geotechnical exploration are described herein For more detailed soil descriptions and stratifications at a particular field test location, the respective "Boring Logs", provided in Appendix 2 should be reviewed. The horizontal 4 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 stratification lines designating the interface between various strata represents approximate boundaries. Transitions between different strata in the field may be gradual in both the horizontal and vertical directions. Therefore, subsurface stratigraphy between test locations may vary. 3.2.1. Surface Materials Surficial organic (topsoil) soils were observed at the existing ground surface of the borings with estimated thicknesses ranging from approximately 2 to 4 inches. The surficial organic soil depths provided in this report and on the individual "Boring Logs" are based on observations of field personnel and should be considered approximate. Please note that the thickness of surface materials at the site should be expected to vary, and measurements necessary for detailed quantity estimation were not performed for this report. For planning purposes, we suggest considering a topsoil thickness of about 12 inches to account for existing vegetation and shallow roots. Surficial Organic Soil is typically a dark -colored soil material containing roots, fibrous matter, and/or other organic components, and is generally unsuitable for engineering purposes. SUMMIT has not performed any laboratory testing to determine the organic content or other horticultural properties of the observed surficial organic soils. Therefore, the phrase "surficial organic soil" is not intended to indicate suitability for landscaping and/or other purposes. 3.2.2. Alluvial Soils Alluvial (water -deposited) soils were not encountered in the borings performed during this exploration. Alluvial soils are typically encountered in or near drainage features, pond bottoms, creeks and in low-lying areas. Alluvial soils are generally loose and/or under - compacted and, as such, are typically unsuitable for supporting the proposed construction. Therefore, remediation may be required wherever alluvial soils are encountered during grading activities. If these soils are encountered during site grading activities, the extent of the alluvial soils should be inspected in the field by the Geotechnical Engineer -of - Record or and/or their designee. Additional testing such as test pit excavations and/or hand 5 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 auger borings may be required in order to further explored the alluvial soils. 3.2.3. Existing Fill Soils Existing fill (disturbed) soils were encountered beneath the surface materials in Borings B- 10 through B-13 to an approximate depth of 1 foot below the existing ground surface. When sampled, the existing fill soils generally consisted of lean clays (CL) and elastic silts (MH). Please note that Borings B-10 through B-13 were performed in an open field that may have been once utilized as an agricultural field (farmland); therefore, these borings existing fill soils could be classified as cultivated fill soils. Cultivated fill soil is a layer that was plowed and disturbed for agricultural purposes. Typically, cultivated fill soils are not suitable for building and/or pavement support and are not suitable to be re -used as structural fill material due to the organics mixed in the soil. However, if approved by the Geotechnical Engineer of Record, the organic stained soils may be suitable as structural fill material if the organic content in the soil is less than 5 percent and/or blended with non -organic soils to reduce the organic content. Also, based on historical aerial photographs and our site observations, previous grading activities and/or development have occurred in isolated areas (i.e., house and pond areas) on the property. As such, the contractor should anticipate the presence of fill soils, active or abandoned utility lines, and/or construction debris that were not encountered in the borings performed during this exploration. If fill soils are encountered at other locations in the field during construction, the fill soils should be inspected by the Geotechnical Engineer -of -Record, or and/or their designee, with respect to the criteria outlined in Section 5.0 of this report. 6 Report of Geotechnical Subsurface Exploration Flowes Store Road 3.2.4. Residual Soils SUMMIT Project No. 0109.G0024 August 28, 2020 Residual (undisturbed) soils were encountered below the surface materials and/or existing fill soils and extended to either the maximum boring termination depth or partially weathered rock (PWR). These residual soils generally consisted of very stiff fat clays (CH), stiff to very stiff lean clays (CL), firm to very stiff elastic silts (MH), firm to hard sandy silts (ML), and medium dense to very dense silty sands (SM). The Standard Penetration Resistances (SPT N-values) in the residual soils ranged from 6 to 56 blows per foot (bpf). 3.2.5. Partially Weathered Rock and Auger Refusal Partially weathered rock (PWR) condition was encountered in Boring B-3 between the approximate depths of 3 to 5.5 and again at approximately 8 feet below the existing ground surface. PWR is defined as soil -like material exhibiting SPT N-values in excess of 100 bpf. When sampled, the PWR generally breaks down into silty sands. Auger refusal condition was encountered in Boring B-3 at an approximate depth of 9.7 feet below the existing ground surface. Auger refusal is defined as material that could not be penetrated by the drilling equipment used during our field exploration. Materials that might result in auger refusal include large boulders, rock ledges, lenses, seams or the top of parent bedrock. Core drilling techniques would be required to evaluate the character and continuity of the refusal material. However, rock coring was beyond the scope of this exploration and not performed. 3.2.6. Groundwater Level Measurements At the time of drilling, groundwater was not observed in the borings performed during this exploration. Please note moisture conditions of the soil samples were noted within some of the borings and moisture conditions within the soils may be an indication of the presence of groundwater. Also, moist to wet soil conditions can be an indication that some manipulation (scarifying and drying) of the soil may be required in order to obtain the specified compaction during grading operations. 7 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 It should be noted that groundwater levels tend to fluctuate with seasonal and climatic variations, as well as with some types of construction operations. Therefore, water may be encountered during construction at depths not indicated in the borings performed for this exploration. Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 4.0 EVALUATIONS AND RECOMMENDATIONS 4.1. General Our preliminary evaluation and recommendations are based on the project information outlined previously and on the data obtained from the field and laboratory testing program. If the structural loading, geometry, or proposed building locations are changed or significantly differ from those outlined, or if conditions are encountered during construction that differ from those encountered by the borings, SUMMIT requests the opportunity to review our recommendations based on the new information and make the necessary changes. Grading plan information with proposed foundation bearing elevations was not available for our review at the time of this report. Finish grade elevations of proposed construction in conjunction with the proposed foundation bearing elevation can have a significant effect on design and construction considerations. SUMMIT should be provided the opportunity to review the project grading plans prior to their finalization with respect to the recommendations contained in this report. 4.2. Shallow Foundation Recommendations Based on the results of the soil test borings, and our assumptions regarding site grading and assumed structural building loads, the proposed structures can be adequately supported on shallow foundation systems provided site preparation and compacted fill recommendation procedures outlined in this report are implemented concerning unsuitable soils such as alluvial soils, existing fill soils, cultivated soils, and fat clays. An allowable net bearing pressure of up to 2,500 pounds per square foot (psf) can be used for design of the foundations bearing on approved undisturbed residual soils, or on approved structural fill compacted to at least 95 percent of its Standard Proctor maximum dry density. Please refer to section 5.0 of this report for more information. Provided the procedures and recommendations outlined in this report are implemented and using the assumed loads, we have estimated a total settlement of less than 1 inch for footing design pressures of 2,500 psf. 9 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 To avoid punching type bearing capacity failure, we recommend wall foundation widths of 18 inches or more. Exterior foundations and foundations in unheated areas should be designed to bear at least 12 inches below finished grade for frost protection. To reduce the effects of seasonal moisture variations in the soils, for frost protection and for bearing capacity, it is recommended that all foundations be embedded at least 12 inches below the lowest adjacent grade. All footing excavations and undercutting remediation operations should be inspected by the Geotechnical Engineer -of -Record or and/or their designee to confirm that suitable soils are present at and below the proposed bearing elevation and that the backfill operations are completed with the recommendations of this report. This evaluation may include hand -auger and DCP testing. If DCP testing encounters lower penetration resistances than anticipated or unsuitable materials are observed beneath the footing excavations, these bearing soils should be corrected per the Geotechnical Engineer-of-Record's recommendations. 4.3. Retaining Wall Recommendations (if used) Design Parameters for backfill properties (i.e., friction angle, earth pressure coefficients) should use the values in the table below. These parameters are based on suitable soils with a minimum moist unit weight of 120 pcf. SUNIlMT should be retained to test the actual soils used for construction to verify these design assumptions. To reduce long term creep or deflections to the wall system, desirable wall backfill soils should be used. These include non -plastic, granular soils (sands and gravels). However, these soils may not be available on site. Soil Parameters for Wall Backfill Active Passive Coefficient Allowable Modulus of Earth Earth of Earth Bearing Friction Subgrade Pressure Pressure Pressure at Capacity Angle Reaction Coefficient Coefficient Rest Slide Backf ll Type (psf) (deg) (Pei) Ka Kp Ko Friction Residuum 2,500 280 200 0.361 2.77 0.531 0.4 Fill 2,500 240 150 0.421 2.37 0.593 0.4 Soils classified as elastic silts (MH) and/or fat clays (CH) shall not be used for wall backfill or in 10 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 the retained zone as shown in Table 1610.1 of the 2018 IBC. If on -site soils are used as backfill within the reinforced zone, the wall designer should address the need for wall drainage and the possibility of long-term, time -dependent movement or creep in their design At the time of report preparation, we were not provided retaining wall plans or specifications. Therefore, we request the opportunity to review the wall plans and specifications once they are finalized and make any necessary changes to our recommendations. Also, we recommend an external stability analysis (including global stability) of the proposed wall(s) be conducted once the site layout and wall geometry is complete. 4.4. Low to Moderate Plasticity Moisture Sensitive Soils (CL and MIS Low to moderate plasticity and moisture sensitive (lean clays and elastic silts) soils were encountered in the majority of the borings performed for this exploration. These fine-grained soils are susceptible to moisture intrusion and can become soft when exposed to weather and/or water infiltration. Consequently, some undercutting and/or reworking (drying) of the near -surface soils may be required depending upon the site management practices and weather conditions present during construction. Should these materials be left in -place, special consideration should be given to providing positive drainage away from the structure and discharging roof drains a minimum of 5 feet from the foundations to reduce infiltration of surface water to the subgrade materials Note: Since Low to Moderate Plasticity and Moisture Sensitive Soils can become remolded (i.e., softened) under the weight of repeated construction traffic and changes in moisture conditions, these soils should be evaluated and closely monitored by the Geotechnical Engineer -of -Record or and/or their designee prior to and during fill placement. Additional testing and inspections of moisture sensitive soils may be warranted such as laboratory testing, field density (compaction) testing, hand auger borings with dynamic cone penetrometer (DCP) testing and/or test pit excavations. 11 Report of Geotechnical Subsurface Exploration Flowes Store Road 4.5. High Plasticity Moisture Sensitive Soils (CH) SUMMIT Project No. 0109.G0024 August 28, 2020 High plasticity and moisture sensitive (fat clays) soils were encountered in Borings B-4 through B-8 to approximate depths of 1 to 3 feet below the existing ground surface. Highly plastic soils can undergo significant changes in volume (shrink/swell behavior) with changes in moisture conditions. These soils typically provide poor subgrade support for pavements and foundations. The following table summarizes the locations and approximate depths that fat clay soils were encountered in the borings performed for this exploration. Summary Table of Fat Clay Soils Depths Boring No. Fat Clay Approx. Depth, (feet)' Boring vo. Fat Clay Approx. Depth (feet)' B-4 1 B-7 3 B-5 1 B-8 3 B-6 1 'Depths were measured from the existing ground surface at the time drilling was performed. The highly plastic materials encountered in the borings performed for this exploration are typically not considered suitable for building or pavement subgrade support. Depending on final subgrade elevations, we recommend the highly plastic soils be undercut from beneath foundations and pavements so that the foundation elements bear on 3 feet or more of engineered fill and pavements are supported on 1'/2 feet or more of engineered fill, creating a separation between the foundation elements/pavements and the underlying highly plastic soils. The presence of the high plasticity materials can adversely affect the performance of the foundation and pavement systems. Due to the presence of highly plastic soils at the project site, we recommend the following be implemented by the design team: L The high plasticity materials should be undercut from all structural and pavement areas. The undercut subgrades should be observed by a SUMMIT staff professional upon completion of undercut operations. Once completed and the subgrade appears suitable, structural fill should be placed to proposed subgrade elevation. 12 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 2. Three (3) feet of separation should be provided between the high plasticity materials and foundations and one and one-half (1'/2) feet of separation on pavement areas. The separation material should consist of approved structural fill materials 3. Lime stabilization techniques could be utilized in order to lower the plasticity of the referenced soils in -place and minimize any undercut. These techniques should extend to a depth of at least 3 feet below finished floor elevation of the building and at least 1.5 feet on pavement areas. It should be noted that the success of lime stabilization techniques is highly dependent upon the means and methods utilized by the contractor. 4. If the expansive soils are not undercut from beneath the structures or adequate separation is not provided, the building foundations should be designed to either penetrate the expansive soils or designed to resist the differential volume change and prevent structural damage. Slab -on -grades should be designed as structural slabs for the expansive soils in accordance with WRI/CRSI Design of Slab -on -Ground Foundations or PTI Design and Construction of Post -Tensioned Slabs -on -Ground. 4.6. Wet Weather Conditions Contractors should be made aware of the moisture sensitivity of the near soils and potential compaction difficulties. If construction is undertaken during wet weather conditions, the surficial soils may become saturated, soft, and unworkable. The contractor can anticipate reworking and/or recompacting soils may be needed when excessive moisture conditions occur. Additionally, subgrade stabilization techniques, such as chemical (lime or lime -fly ash) treatment, may be needed to provide a more weather -resistant working surface during construction. Therefore, we recommend that consideration be given to construction during the dryer months. Surface runoff should be drained away from excavations and not allowed to pond. Concrete for foundations should be placed as soon as practical after the excavation is made. That is, the exposed foundation soils should not be allowed to become excessively dry or wet before placement of concrete. Bearing soils exposed to moisture variations may become highly disturbed resulting in 13 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 the need for undercutting prior to placement of concrete. If excavations must remain open overnight, or if rainfall becomes imminent while the bearing soils are exposed, we recommend that a 2- to 4-inch-thick "mud -mat" of lean (2000 psi) concrete be placed on the bearing soils before work stops for the night. SUMMIT recommends that special care be given to providing adequate drainage away from the building areas to reduce infiltration of surface water to the base course and subgrade materials. If these materials are allowed to become saturated during the life of the slab section, a strength reduction of the materials may result causing a reduced life of the section. 4.7. Floor Slabs Slab -on -grade floor systems may be supported on approved residual soils, or newly compacted fill, provided the site preparation and fill placement procedures outlined in this report are implemented. Depending upon the amount of cuts and/or fills, unsuitable soils such as alluvial soils, existing fill soils, cultivated soils, fat clays, and areas which deflect, rut or pump excessively during proof -rolling may require remediation as described in Section 5.2. We recommend floor slabs be isolated from other structural components to allow independent movement of the slab and the building foundation elements. Immediately prior to constructing a floor slab, the areas should be proof -rolled to detect any softened, loosened or disturbed areas that may have been exposed to wet weather or construction traffic. Areas that are found to be disturbed or indicate pumping action during the proof -rolling should be undercut and replaced with adequately compacted structural fill. This proof -rolling should be observed by a SUMMIT staff professional or a senior soils technician under his/her direction. Proof -rolling procedures are outlined in the "Site Preparation" section of this report. 4.8. Pavements Subgrade Preparation The pavement sections can be adequately supported on approved non -high plasticity residual soils, or newly compacted fill, provided the site preparation and fill placement procedures outlined in this report are implemented. Immediately prior to constructing the pavement section, we 14 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 recommend that the areas be proofrolled to detect any softened, loosened or disturbed areas that may have been exposed to wet weather or construction traffic. Areas that are found to be disturbed or indicate instability during the proofrolling should be undercut and replaced with adequately compacted structural fill or repaired as recommended by the Geotechnical Engineer of Record. This proofrolling should be observed by a SUMMIT professional or a senior soils technician under his/her direction. Proofrolling procedures are outlined in the "Site Preparation" section of this report. Due to prevalence of near surface low to high plasticity elastic silts and fat clays, remediation of pavement subgrade soils may be recommended (as determined by the Geotechnical Engineer of Record during construction) including undercutting and replacement with additional NCDOT ABC stone. Alternatively, lime stabilization of pavement subgrade may be a more economical option and SUMMIT can provide lime stabilization mix design services if requested. This may be more pronounced depending on the time of the year and seasonal conditions at the time of pavement construction. We recommend contingency for some remediation efforts for the subgrade soils be considered during the planning stage. 4.9. Cut and Fill Slopes Permanent project slopes should be designed with geometry of 3 horizontal to 1 vertical (31-1:1V) or flatter. The tops and bases of all slopes should be located 10 feet or more from structural limits and 5 feet or more from parking limits. Fill slopes should be constructed utilizing properly compacted, structural fill according to the recommendations provided in this report. In addition, fill slopes should be overbuilt and cut to finished grade during construction to achieve proper compaction on the slope face. All slopes should be seeded, stabilized and maintained after construction and adhere to local, state and federal municipal standards, if applicable. Immediately prior to constructing the project slopes, the areas should be proof -rolled to detect any softened, loosened or disturbed areas that may have been exposed to wet weather or construction traffic. Areas that are found to be disturbed or indicate pumping action during the proof -rolling should be undercut and replaced with adequately compacted structural fill. This proof -rolling 15 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 should be observed by a SUMMIT staff professional or a senior soils technician under his/her direction. Proof -rolling procedures are outlined in the "Site Preparation" section of this report. Structural Pill should not be placed on a subgrade with a slope steeper than 5 horizontal to 1 vertical (51-1:1V), unless the fill is confined by an opposing slope, such as in a ravine. Otherwise, where steeper slopes exist, the subgrade should be benched to allow for fill placement on a horizontal surface. 16 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 5.0 CONSTRUCTION CONSIDERATIONS 5.1. Abandoned Utilities/Structures SUMMIT recommends that any existing utility lines, septic tank and drainfield(s) and foundations be removed from within proposed building and pavement areas. The utility backfills, septic tank and drainfield(s) and foundation material should be removed and the subgrade in the excavations should be inspected by a geotechnical professional prior to fill placement. The subgrade inspection should consist of visual observations, probing with a steel rod and/or performing hand auger borings with Dynamic Cone Penetrometer tests to explore their suitability of receiving structural fill. Once the excavations are inspected and approved, they should be backfilled with adequately compacted structural fill. Excavation backfill under proposed new foundations should consist of properly compacted structural fill, crushed stone, flowable fill or lean concrete as approved by the Geotechnical Engineer -of -Record. 5.2. Site Preparation Based on the results of our borings, and dependent on final grades, the contractor can anticipate that some undercutting and/or foundation extension through alluvial soils, existing fill soils, cultivated soils, fat clays, and soils with N-values less than 7 bpf may be required prior to building construction and/or fill placement. If these soils are encountered during the grading activities, the extent of the undercut required should be determined in the field by the Geotechnical Engineer -of - Record and/or their designee. Additional testing such as test pit excavations and/or hand auger borings may be required in order to further explore these soil conditions, depths and locations. Topsoil, organic laden/stained soils, construction debris and other unsuitable materials should be stripped/removed from the proposed construction limits. Stripping and clearing should extend 10 feet or more beyond the planned construction limits. Upon completion of the stripping operations, we recommend areas planned for support of foundations, floor slabs, parking areas, slope areas and structural fill be proof -rolled with a loaded dump truck or similar pneumatic tired vehicle (minimum loaded weight of 20 tons) under the observations of a staff brofessional. After 17 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 excavation of the site has been completed, the exposed subgrade in cut areas should also be proof - rolled. The proof -rolling procedures should consist of four complete passes of the exposed areas, with two of the passes being in a direction perpendicular to the proceeding ones. Any areas which deflect, rut or pump excessively during proof -rolling or fail to "tighten up" after successive passes should be undercut to suitable soils and replaced with compacted fill. The extent of any undercut required should be determined in the field by a SUMMIT staff professional or engineer while monitoring construction activity. After the proof -rolling operation has been completed and approved, final site grading should proceed immediately. If construction progresses during wet weather, the proof -rolling operation should be repeated after any inclement weather event with at least one pass in each direction immediately prior to placing fill material or aggregate base course stone. If unstable conditions are experienced during this operation, then undercutting or reworking of the unstable soils may be required. 5.3. Difficult Excavation Based on the results of our soil test borings and dependent on final grades, it appears that the majority of general excavation for footings and utilities will be possible with conventional excavating techniques. We anticipate that the residual soils can be excavated using pans, scrapers, backhoes, and front end loaders. Depending on the location, excavations deeper than approximately three (3) feet may require specialized equipment and procedures. Even though Partially Weathered Rock (PWR) and auger refusal conditions were encountered in only one (1) of the borings performed for this exploration, the depth and thickness of partially weathered rock, boulders, and rock lenses or seams can vary dramatically in short distances and between the boring locations; therefore, soft/hard weathered rock, boulders or bedrock may be encountered during construction at locations or depths, between the boring locations, not encountered during this exploration. 18 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 The table below may be used as a quick reference for rippability of in -place materials. Summary of Rippability Based on SPT N-Values N-Values as Shown Description of N-Values Anticipated Rippability on Boring Logs These materials may generally be excavated 60 < N-Value N-values less than 60 bpf with heavy-duty equipment such as a Caterpillar D-8 with a single -shank ripper N-values more than 60 bpf, These materials are considered marginally 60 < N-Value < 50/3" but less than 50 blows per 3 excavatable, even with heavy-duty inches of penetration equipment. N-values more than 50 blows Blasting and/or removal with impact 50/3" < N-Value per 3 inches of penetration hammers is typically required to excavate these materials. *This table is for general information only. Actual rippability is dependent upon many other factors as stated above. Care should be exercised during excavations for footings on rock to reduce disturbance to the foundation elevation. The bottom of each footing should be approximately level. When blasting is utilized for foundation excavation in rock, charges should be held above design grades. Actual grades for setting charges should be selected by the contractor and he should be responsible for any damage caused by the blasting. All loose rock should be carefully cleaned from the bottom of the excavation prior to pouring concrete. Footing excavations in which the rock subgrade has been loosened due to blasting should be deepened to an acceptable bearing elevation. In our professional opinion, a clear and appropriate definition of rock should be included in the project specifications to reduce the potential for misunderstandings. A sample definition of rock for excavation specifications is provided below: Rock is defined as any material that cannot be dislodged by a Caterpillar D-8 tractor, or equivalent, equipped with a hydraulically operated power ripper (or by a Cat 325 hydraulic backhoe, or equivalent) without the use of drilling and blasting. Boulders or masses of rock exceeding % cubic yard in volume shall also be considered rock excavation. This classification does not include materials such as loose rock, concrete, or other materials that can be removed by means other than drilling and blasting, but which for any reason, such as economic reasons, the Contractor chooses to remove by drilling and blasting. 19 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 5.4. Temporary Excavation Stability Localized areas of soft or unsuitable soils not detected by our borings, or in unexplored areas, may be encountered once grading operations begin. Vertical cuts in these soils may be unstable and may present a significant hazard because they can fail without warning. Therefore, temporary construction slopes greater than 5 feet in height should not be steeper than two horizontal to one vertical (2H:IV), and excavated material should not be placed within 10 feet of the crest of any excavated slope. In addition, runoff water should be diverted away from the crest of the excavated slopes to prevent erosion and sloughing. Should excavations extend below final grades, shoring and bracing or flattening (laying back) of the slopes may be required to obtain a safe working environment. Excavation should be sloped or shored in accordance with local, state and federal regulations, including OSHA (29 CFR Part 1926) excavation trench safety standards. 5.5. Structural Fill Soil to be used as structural fill should be free of organic matter, roots or other deleterious materials. Structural fill should have a plasticity index (PI) less than 25 and a liquid limit (LL) less than 50 or as approved by the Geotechnical Engineer -of -Record. Compacted structural fill should consist of materials classified as either CL, ML, SC, SM, SP, SW, GC, GM, GP, or GW per ASTM D-2487 or as approved by the Geotechnical Engineer -of -Record. Off -site borrow soil should also meet these same classification requirements. Non -organic, low -plasticity on -site soils are expected to meet this criterion. However, successful reuse of the excavated, on -site soils as compacted structural fill will depend on the moisture content of the soils encountered during excavation. We anticipate that scarifying and drying of portions of the on -site soils will be required before the recommended compaction can be achieved. Drying of these soils will likely result in some delay. 20 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 All structural fill soils should be placed within the proposed structural pad and extending at least 5 feet beyond the perimeter of the pad and foundation limits. All structural fill soils should be placed in thin (not greater than 8 inches) loose lifts and compacted to a minimum of 95 percent of the soil's Standard Proctor maximum dry density (ASTM D 698) at/or near optimum moisture content (±2 percent). The upper 2 feet of structural fill should be compacted to a minimum of 100 percent of the soil's Standard Proctor maximum dry density (ASTM D 698) at/or near optimum moisture content (±2 percent). Some manipulation of the moisture content (such as wetting, drying) may be required during the filling operation to obtain the required degree of compaction. The manipulation of the moisture content is highly dependent on weather conditions and site drainage conditions. Therefore, the grading contractor should be prepared to both dry and wet the fill materials to obtain the specified compaction during grading. Sufficient density tests should be performed to confirm the required compaction of the fill material. Structural Fills Greater than 10 feet Discussions: Soil undergoes both primary and secondary consolidation (compression of the soil). Primary consolidation can take place over a short-term during the mechanical compacting process. Secondary consolidation can take place over a long- term and can place after the compaction process is complete and the permanent loads are in place. The amount of secondary consolidation which can be expected increases with the depth of fill soils and structure loads. Therefore, in order to reduce secondary consolidation, we recommend when either mass fills or utility lines are more than 10 feet deep, the fill/backfill material below 10 feet should be compacted to at least 98 percent of standard Proctor maximum dry density (ASTM D 698) and within 2 percentage points of the material's optimum moisture content. The portion of the fill/backfill shallower than 10 feet should be compacted as outlined above. Another option is to monitor the settlement with settlement plates embedded at the proposed subgrade level. After the magnitude and rate of settlement are within acceptable levels, then foundation and slab -on grade construction may commence. Based on our previous experience and dependent on soil types at the site, we anticipate the time required to reduce settlements to an acceptable level may be on the order of 30 to 120 days. 21 Report of Geotechnical Subsurface Exploration SUMMIT Project No. 0109.G0024 Flowes Store Road August 28, 2020 5.6. Suitability of Excavated Soils for Re -Use Except for the fat clays soils encountered during this exploration, the soils encountered in the borings should be suitable to be used as structural fill material provided the recommendations in this report are implemented. These soils may be utilized as non-structural fill and backfill at landscaped or non -pavement areas of the project. We recommend non-structural fill to be compacted to at least 92 percent of the soil's Standard Proctor Maximum Dry Density to reduce settlement of the fill soils particularly over utility trenches. However, if approved by the Geotechnical Engineer -of -Record, high plasticity soils encountered during general site grading can be mixed/blended and/or mixed with lower plasticity soils and used as structural fill. We recommend that mixed soils be used below the top five (5) feet at deeper fill locations and adequate drainage be provided away from structural and pavement areas. The top five (5) feet should consist of materials classified as either CL, ML, SC, SM, SP, SW, GC, GM, GP or GW per ASTM D-2487 or as approved by the Geotechnical Engineer -of -Record. All fill soils should be placed in thin (not greater than 8 inches) loose lifts and compacted to a minimum of 95 percent of the soil's Standard Proctor maximum dry density (ASTM D 698) at near optimum moisture content (±2 percent). 5.7. Engineering Services During Construction As previously stated, the engineering recommendations provided in this report are based on the project information outlined above and the data obtained from field and laboratory tests. However, unlike other engineering materials like steel and concrete, the extent and properties of geologic materials (soil) vary significantly. Regardless of the thoroughness of a geotechnical engineering exploration, there is always a possibility that conditions between borings will be different from those at the boring locations, that conditions are not as anticipated by the designers, or that the construction process has altered the subsurface conditions. This report does not reflect variations that may occur between the boring locations. Therefore, conditions on the site may vary between the discrete locations observed at the time of our subsurface exploration. 22 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 The nature and extent of variations between the borings may not become evident until construction is underway. To account for this variability, professional observation, testing and monitoring of subsurface conditions during construction should be provided as an extension of our engineering services. These services will help in evaluating the Contractor's conformance with the plans and specifications. Because of our unique position to understand the intent of the geotechnical engineering recommendations, retaining us for these services will also allow us to provide consistent service through the project construction. Geotechnical engineering construction observations should be performed under the supervision of the Geotechnical Engineer -of -Record from our office who is familiar with the intent of the recommendations presented herein. This observation is recommended to evaluate whether the conditions anticipated in the design actually exist or whether the recommendations presented herein should be modified where necessary. Observation and testing of compacted structural fill and backfill should also be provided by our firm. 23 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 August 28, 2020 6.0 RELIANCE AND QUALIFICATIONS OF REPORT This geotechnical subsurface exploration has been provided for the sole use of Shea Homes. This geotechnical subsurface exploration should not be relied upon by other parties without the express written consent of SUMMIT and Shea Homes. The analyses and recommendations submitted in this report were based, in part, on data obtained from this exploration. If the above -described project conditions are incorrect or changed after the issuing of this report, or subsurface conditions encountered during construction are different from those reported, SUMMIT should be notified and these recommendations should be re-evaluated based on the changed conditions to make appropriate revisions. We have prepared this report according to generally accepted geotechnical engineering practices. No warranty, express or implied, is made as to the professional advice included in this report. 24 Report of Geotechnical Subsurface Exploration Flowes Store Road SUMMIT Project No. 0109.G0024 SUMMIT ENGINEERING . 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LABORATORY • TESTING APPENDIX 2 — Boring Logs August 28, 2020 SUMMIT ENGINNERING, LABORATORY AND TESTING PC KEY TO SYMBOLS /. 3575 CENTRE CIRCLE DRIVE - FORT MILL, SOUTH CAROLINA 25273 SUMMIT 704.504.1717 ­........ aaoa.r­r ....... WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina LITHOLOGIC SYMBOLS SAMPLER SYMBOLS (Unified Soil Classification System) Standard Penetration Test F-1 BLANK ® CH: USCS High Plasticity Clay ® CL: USCS Low Plasticity Clay FILL: Fill (made ground) ® MH: USCS Elastic Silt MLS: USCS Sandy Silt SM: USCS Silty Sand WELL CONSTRUCTION SYMBOLS TOPSOIL: Topsoil Ty. PWR: Partially Weathered Rock ABBREVIATIONS LL -LIQUID LIMIT (%) TV -TORVANE PI -PLASTIC INDEX (%) PID - PHOTOIONIZATION DETECTOR W - MOISTURE CONTENT (%) UC -UNCONFINED COMPRESSION DD - DRY DENSITY (PCF) ppm -PARTS PER MILLION NP -NON PLASTIC Water Level at Time -200 - PERCENT PASSING NO. 200 SIEVE Drilling, or as Shown PP - POCKET PENETROMETER (TSF) Water Level at End of 1 Drilling, or as Shown Water Level After 24 - Hours, or as Shown SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-1 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/20/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a7' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (MH) RESIDUUM: ........ ....:..._._.........:. ..... Very Stiff Red Slightly Sandy Elastic SILT SPT 7-11-13 1 (24) ........:........:........:........:........ 2.s SPT 5-8-13 2 (21) ................:........................ 5.0 (ML) Stiff Light Red and Yellow Sandy SILT SPT 3-4-5 7ft - 3 (9) " — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Firm Light Yellowish Brown and Yellow Sandy SILT ........:........:........ SPT 3-3-4 4 (7) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Stiff Light Gray and Yellow Sandy SILT ....... ;........:........ ;........ :........ 12.5 SPT 3-4-6 5 10 ( ) Is.o Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-2 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/20/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a8.5' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL Mc LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 4" of Topsoil (ML) RESIDUUM: ........ ....:..._._.........:. ..... Very Stiff Light Brown and White Sandy SILT SPT 10-10-14 1 (24) 2.5 ............................................ SPT 9-13-17 2 (30) 5.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Stiff Moist Light Brown, Light Gray and White Sandy SILT ........;.......;........;........;........ SPT 6-7-7 ........................................... 3 (14) ............................................ 7.5 (SM) Medium Dense Moist Light Brown, Light Gray and White Silty SAND 8.5ft - _ ...... SPT 6-7-9 4 (16) 10.0 .' 12.5 ................................... SPT 6-7-9 5 (16) 15.0 '. Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-3 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/20/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a6.5' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- w o A SPT N VALUE A p U } U) w 0 20 40 60 80 100 PL MC LL _ Q a O MATERIAL DESCRIPTION �w J ED o^ LU > I —D p Z Q > ry J a O- m O> 0 20 40 60 80 100 (D �Z U� UZ w < LU El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (CL) RESIDUUM: ........ ....:..._._.........:. ..... Moist Grayish Brown Sandy Lean CLAY (ML) Hard Light Grayish Brown Slightly Clayey Sandy SILT SPT 8-14-32 ........:................ 1 (46) .................... ...... ; ........ _ s , ::• ._•;:_: (SM) Partially Weathered Rock (PWR) when sampled becomes Light Olive Brown and Light Gray Silty SAND with a trace of Rock .......................................... SPT 2 22-36-50 (50/3") Fragments 5.0 - ...... ...... ..... ...... ... (ML) Hard Olive Brown, Yellow and White Slightly Clayey Sandy SILT _ 6.5ft - SPT 11-15-33 ........ ........ :..... ..:........ :........ 3 (48) 7.5 ._•;:_: ........: -: (SM) Partially Weathered Rock (PWR) when sampled becomes Light Gray, Olive Brown and White Silty SAND with a trace of SPT 4 6-30-50 (50/2") € Rock Fragments ........ :........:........ :........ :........ lo.o Bottom of Boring at 9.7 feet bgs, Auger Refusal SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-4 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/20/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a8' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (CH) RESIDUUM: ........ ....:..._._.........:. ..... Moist Brown Sandy Fat CLAY (ML) Very Stiff Light Gray and White Slightly Clayey Sandy SILT with some Rock Fragments SPT 5-6-15 1 (21) ........:........:. 2.5 SPT 8-10-12 2 (22) 5.0 (ML) Very Stiff Light Gray, Light Brown and White Slightly Clayey Sandy SILT SPT 5-7-9 3 (16) ........................................... 7.5 8ft - SPT 5-7-9 4 (16) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Stiff Moist Light Gray, Light Brown and White Slightly Clayey ........;........:........ z.s Sandy SILT SPT 3-4-8 5 12 15.0 Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-5 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/20/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a9' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (CH) RESIDUUM: ........ ....:..._._.........:. ..... Moist Brown Sandy Fat CLAY (ML) Very Stiff Moist Grayish Brown and Light Brown Slightly Clayey Sandy SILT SPT 6 8 10 ........ ................ :........ ...... 1 (18) z. s .......................... ................ . SPT 4-6-10 2 (16) 5.0 (ML) Stiff Moist Grayish Brown, Light Brown and White Slightly Clayey Sandy SILT ............................................ SPT 5-5-8 3 (13) ............................................ �.s " — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Firm Moist Gray, Light Brown and Black Slightly Clayey .......:........:.......................... Sandy SILT 9ft - SPT 3-3-5 ... .... :........:........ :........:........ 4 (8) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Stiff Moist Gray, Light Brown and Black Slightly Clayey ....... ;........:........ ;........ :........ z.s Sandy SILT with a trace of Rock Fragments SPT 5-5-5 5 10 Is.o : Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-6 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/20/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a8.5' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 4" of Topsoil (CH) RESIDUUM: ........ ....:..._._.........:. ..... Moist Brown Sandy Fat CLAY (CL) Stiff Grayish Brown, Red and White Sandy Lean CLAY SPT 5-5-9 1 (14) ..... ..:........ :........ :........ :........ z. s (MH) Very Stiff Red, Light Brown, White and Black Sandy Elastic SILT ........:.... ............................... SPT 4-10-20 2 (30) 5.0 NINE (SM) Medium Dense Red, Black and White Slightly Clayey Silty SAND with a trace of Rock Fragments SPT 7-13-17 3 (30) 7.s 8.5ft - SPT 7-13-13 4 (26) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (SM) Very Dense Light Brown and Yellow Silty SAND ........;........: ....... ;........ :........ 12.5 SPT E5 Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-7 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a8' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (CH) RESIDUUM: ........ ....:..._._.........:. ..... Very Stiff Dark Red Sandy Fat CLAY SPT 7-9-12 1 (21) ........:........:........:........:........ 2.s 01 (MH) Very Stiff Red, Light Brown and Black Sandy Elastic SILT SPT 6-8-10 2 (18) 5.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (MH) Stiff Red, Light Brown and Black Sandy Elastic SILT .......;........;................. ;........ SPT 4-6-7 .......:........:........:........:........ 3 (13) (ML) Stiff Red, Light Brown and Black Slightly Clayey Sandy SILT SPT 3-4-5 4 (9) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Firm Moist Red, Light Brown and Black Slightly Clayey ....... ;........:........ ;........ :........ z.s Sandy SILT SPT F5 3-4-4 (8) ,so Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-8 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a7' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I -D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (CH) RESIDUUM: ........ ....:..._._.........:. ..... Very Stiff Dark Reddish Brown Sandy Fat CLAY with a trace of Rock Fragments SPT 8-8-14 1 (22) ........:.......:........:........:........ 2.5 01 (MH) Very Stiff Dark Red, Light Brown and Black Sandy Elastic SILT......... ................................. SPT 6-10-16 2 (26) ........ ........ :........ ........ ........ 5.0 ........:........:........:........:........ SPT 8-10-16 7ft- 3 (26) ........ :........:........ :........ :........ 7.5 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (MH) Very Stiff Light Yellowish Brown, Red and Black Sandy ........:.......:........:........:........ Elastic SILT ........;. ...... :......... ..... SPT 6-10-14 4 (24) 10.0 . (ML) Stiff Grayish Brown Sandy SILT 12.5 .... ...... ........ ........ ........ SPT 4-6-7 5 13 15.0 Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-9 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a8' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J (D w MATERIAL DESCRIPTION w �w J ED a �Z < o } ^ o LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 4" of Topsoil (MH) RESIDUUM: _ ....:..._. .........:. ..... Very Stiff Dark Red Sandy Elastic SILT SPT 7-7-10 1 (17) ........:........:........:........:........ 2.s — — — — — — — — — — — — — — — — — — — — — — — — — — — — (MH) Stiff Red and Light Brown Sandy Elastic SILT ............................................ SPT 3-5-7 2 (12) 5.0 (ML) Stiff Moist Red, Light Brown and Black Slightly Clayey Sandy SILT SPT 3-4-5 3 (9) " -------------------------- _ (ML) Firm Moist Red, Light Brown and Black Slightly Clayey ........:........:...... Sandy SILT SPT 2-3-4 4 (7) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Firm Moist Red, Light Brown and Black Slightly Clayey ........ ;........:........ ;........ :........ z.s Sandy SILT SPT 2-4 4 5 (8) ...... 15.0 Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-10 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a7.5' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J w 0 MATERIAL DESCRIPTION w I--w J ED a �Z < o } ^ of LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 4" of Topsoil (MH) FILL: (Cultivated Fill Soil) ........' -' Moist Red Sandy Elastic SILT (MH) RESIDUUM: Stiff Red, Light Brown and Black Sandy Elastic SILT SPT 4-6-9 1 (15) ....... .:........ :........ :........ :........ 2.s SPT 4-4-6 2 (10) 5.0 (ML) Firm Moist Light Brown, Light Gray and Black Slightly Clayey Sandy SILT ........................................... SPT 2-3-5 3 (8) 7.s :. ..: 7.5ft - ............. ........ :........ SPT 3-3-3 4 (6) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Firm Moist Grayish Brown, Light Gray and Black Slightly ........ ;........:........ ;........ :........ z.s Clayey Sandy SILT SPT F5 3-3 5 (8) ...... 15.0 Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-11 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a7.5' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J w 0 MATERIAL DESCRIPTION w I--w J ED a �Z < o } ^ of LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (MH) FILL: (Cultivated Fill Soil) """""- Moist Red Sandy Elastic SILT (MH) RESIDUUM: Stiff Brownish Gray, Olive Brown, White and Black Sandy Elastic SILT SPT 1 5-6-8 (14) 2.s (ML) Stiff Moist Brownish Gray, Light Brown, White and Black Slightly Clayey Sandy SILT ........:........:........:........:........ SPT 5-6-8 2 (14) 5.0 " — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Stiff Gray and White Slightly Clayey Sandy SILT ........;........;........;........;........ SPT 5-7-8 3 (15) ............................................ 7.s :. ..: 7.5ft - SPT 4-6-7 4 (13) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Very Stiff Gray, White and Black Slightly Clayey Sandy SILT ........ ;........:........ ;........ :........ 12.5 SPT 6 9-11 5 20 Is.o Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-12 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a9' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J w 0 MATERIAL DESCRIPTION w I--w J ED a �Z < o } ^ of LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 2" of Topsoil (CL) FILL: (Cultivated Fill Soil) """""- Very Stiff Light Grayish Brown Sandy Lean CLAY (CL) RESIDUUM: Very Stiff Light Grayish Brown and Light Brown Sandy Lean CLAY SPT 1 7-9-12 (21) z. s ................:........:........:........ (ML) Very Stiff Light Grayish Brown, Light Brown and Black Slightly Clayey Sandy SILT SPT 5-9-10 .................. . ................ . 2 (19) 5.0 ...................................:........ SPT 5-7-9 3 (16) 7.s 9ft - SPT 4-7-11 4 (18) 10.0 '. — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Stiff Gray, Light Brown, White and Black Sandy SILT ........;.................;........:........ 12.5 SPT 4-5-7 5 12 15.0 Bottom of Boring at 15 feet bgs, Boring Terminated SUMMIT ENGINNERING, LABORATORY AND TESTING PC BORING NUMBER B-13 11AM1k 3575 CENTRE CIRCLE DRIVE FORT MILL, SOUTH CAROLINA 28273 PAGE I OF I SUMMIT 704.504.1717 WWW.SUMMIT-COMPANIES.COM CLIENT Shea Homes PROJECT NAME Flowes Store Road PROJECT NUMBER 109.G0024 PROJECT LOCATION Midland, North Carolina DATE STARTED 8/21/20 COMPLETED GROUND ELEVATION HOLE SIZE 6 inches DRILLING CONTRACTOR SUMMIT GROUND WATERICAVE-IN: DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --- GW NE ATD / Caved in Depth (a8' bqs LOGGED BY D. Robles CHECKED BY F. Newsom AT END OF DRILLING --- NOTES See Figure 2 "Boring Location Plan" for Approx. Boring Location AFTER DRILLING --- p U _ Q a O > ry J w 0 MATERIAL DESCRIPTION w I--w J ED a �Z < o } ^ of LU > O- U� LU U) w I —D p Z Q m O> UZ A SPT N VALUE A 0 20 40 60 80 100 PL MC LL 0 20 40 60 80 100 El FINES CONTENT (%) El 0 20 40 60 80 100 Approx. 3" of Topsoil (CL) FILL: (Cultivated Fill Soil) ........' -' Moist Brown Sandy Lean CLAY (MH) RESIDUUM: Firm Moist Light Brown and Black Sandy Elastic SILT SPT 3-3-5 1 (8) ....... :........ :........ :........ z. s SPT 3-3-5 2 (8) 5.0 in (ML) Stiff Moist Grayish Brown, Light Brown, White and Black Slightly Clayey Sandy SILT ........................................... SPT 5-5-7 3 (12) ............................................ " — — — — — — — — — — — — — — — — — — — — — — — — — — _ (ML) Firm Moist Grayish Brown, Light Brown, White and Black Slightly Clayey Sandy SILT ...... .. SPT 3-3-4 4 (7) 10.0 — — — — — — — — — — — — — — — — — — — — — — — — — — — — (ML) Firm Moist Gray, White and Black Slightly Clayey Sandy ........ ;.... .... :...... ..;........ :........ I2.s SILT FSPT 3-3-5 5 (8) ...... Is.o Bottom of Boring at 15 feet bgs, Boring Terminated