Fauquier County Cedar Lee Middle School Safety Routes to School Bealeton, Virginia

Transcription

1 Geotechnical Report Fauquier County Cedar Lee Middle School Safety Routes to School Project Number: GEO April 30, 2015 Prepared for McCormick Taylor, Inc. 113 Mill Place Parkway, Unit 103 Verona, VA Midlothian Turnpike, Suite 230 Midlothian, VA 23113

2 April 30, 2015 McCormick Taylor, Inc. 113 Mill Place Parkway, Unit 103 Verona, VA Attention: Mr. Gregory E. Krystyniak, P.E. Senior Transportation Engineer Re: Geotechnical Report Fauquier County Cedar Lee Middle School Safe Routes to School DMY Project Number: GEO Dear Mr. Krystyniak: DMY Inc. is pleased to submit this geotechnical report for the proposed Fauquier County Cedar Lee Middle School Safe Routes to School (SRTS) located in. We are pleased to transmit herewith an electronic copy of our report. This report describes the exploratory procedures, field and laboratory findings, engineering analyses, and presents our engineering recommendations and comments related to the design and construction of the project. The appendices contain a site location map, a boring location plan, logs of test borings, laboratory test results, and results of engineering analyses of stability of the dam slopes. Representative soil samples obtained during the course of this exploration will be held at this office for a period of three (3) months and will then be discarded unless otherwise notified. We appreciate the opportunity to offer these services. If you have any questions regarding this report or if we may be of further assistance to you, please contact our office at (804) Respectfully yours, DMY Inc. John Z. Ding, P.E. Principal Engineer Richard M. Simon, P.E., Ph.D., D.GE Senior Principal Geotechnical Engineer

3 Table of Contents 1.0 Introduction 1.1 Project Information Purpose and Scope Subsurface Explorations 2.1 Field Explorations Laboratory Testing Subsurface Conditions 3.1 Regional Geology Soil Stratification Groundwater Site Seismic Classification Engineering Recommendations 4.1 Foundation Retaining Wall Construction Considerations 5.1 General Wet Weather Earthwork Limitations of Liability 12 DMYGEO

4 List of Tables 2-1 Boring Designations 2-2 Laboratory Test Items and Related Standards 2-3 Atterberg Limits Test Results 5-1 Fill Material Requirements List of Figures A-1 Site Vicinity Map A-2 Boring Location Plan List of Appendices A B Unified Soil Classification System (USCS) and Boring Logs Laboratory Test Results DMYGEO

5 Section 1 Introduction 1.1 Project Information Fauquier County Government and Public Schools has established a Safe Routes to School (SRTS) project for Cedar Lee Middle School located in Bealeton, VA. The major component of this project includes a trail along School House Road, sidewalk improvements along School House Road, and a trail under Rt. 17 and along Remington Road that connects to existing sidewalks and associated safety measures to improve the safety of patrons traveling to and from the school. As a major component of the project, there will be a 70 x 14 continental connector bridge crossing Bowens Run Creek under School House Road. The design of the bridge requires a geotechnical exploration and recommendations for the bridge foundation. 1.2 Purpose and Scope This report describes the results of the geotechnical field and laboratory exploration and office analysis and study used to develop geotechnical recommendations related to the design and construction of the proposed bridge. The scope of the geotechnical study included a review of the available geotechnical related information and site geological literature, field and laboratory testing, and an engineering evaluation of the materials and conditions encountered at the site. The engineering recommendations regarding the design and construction of the project are discussed in the following sections of this report. DMYGEO

6 Section 2 Subsurface Explorations 2.1 Field Explorations Two (2) borings were initially planned for the project. Three soil borings were actually conducted in the field to identify the subsurface soil and bedrock conditions. The borings were drilled at the project site employing split spoon sampling techniques per ASTM D1586 using conventional hollow stem augers powered by an All-Terrain Vehicle (ATV) mounted drill rig. The sampling and penetration testing procedures were performed by driving a standard 1⅜-inch-inside-diameter, 2-inch-outside-diameter split spoon sampler with a 140-lb. automatic hammer falling from a height of 30 inches. The number of hammer blows required to drive the sampler 6 inches was recorded for a total of 18 inches. The penetration resistance value (N value) is the summation of the last two 6-inch increments. The N values are recorded on the boring logs. The results of the standard penetration tests indicate the comparative consistency of the cohesive soils and relative density of the cohesionless soils, and are used as an index to derive soil parameters from various empirical correlations. The soil samples obtained were visually classified using terms and descriptions in the Appendices. Selected samples were transported to a geotechnical laboratory for index testing. TABLE 2-1 Boring Designations Boring Number Maximum Boring Depth (ft.) Latitude (N) Boring Coordinates Longitude (W) B ' '16.97" B '28.94" '16.01" B '29.30" '16.55" 2.2 Laboratory Testing The soil samples obtained during the drilling and auger operations were placed in labeled sample containers that were sealed to limit moisture change. The DMY geotechnical engineer performed visual classification of the samples in accordance with ASTM D2488 using the Unified Soil Classification System (USCS). Representative samples were tested for the purpose of classification and index DMYGEO

7 properties. The types of tests and related standards are listed in Table 2-2. The test results are summarized in Table 2-3. A log of each boring, including laboratory test results, visual classification of the samples, and driller observations are provided in the Appendix of this report. TABLE 2-2 Laboratory Test Items and Related Standards Type of Test Soil Natural Moisture Contents Soil Visual Classification Atterberg Limits Standard ASTM D2216 ASTM D2488 ASTM D4318 TABLE 2-3 Atterberg Limit Test Results Boring No. Sample & Depth Atterberg Limits LL PL PI USCS B-1 S-2/S-3 ( ) GC B-2 S-3/S-4 ( ) CH B-3 S-2/S-3 ( ) CL DMYGEO

8 Section 3 Subsurface Conditions 3.1 Regional Geology Fauquier County, located approximately 40 miles west of the Nation's Capital in northern Virginia, is roughly rectangular in shape and covers approximately 660 square miles. The County is bounded to the west by Culpeper and Rappahannock counties, to the south by Stafford County, to the north by Loudoun, Warren, and Clarke counties, and to the east by Prince William County. The County spans three geological provinces- the Blue Ridge, the Culpeper (Triassic Basin), and the Piedmont. The northwestern half of the County, which is dominated by the Blue Ridge, is characterized by mountainous and rolling terrain, while the central portion, which is dominated by the Culpeper Basin, is nearly level to gently rolling. The extreme southeastern portion, which is dominated by the Piedmont, is gently rolling to rolling in nature. Forest vegetation covers approximately one-third of the County's land area, while the remainder is largely open land utilized for a variety of agricultural purposes. The project site lies within the Culpeper Basin Physiographic Province of Virginia. The Triassic Basins lie in a band of dispersed, non-contiguous units spread throughout the general Appalachian and Piedmont regions of the eastern United States. These basins were formed in the geologic time known as the Triassic period. The basins are not extensive nor are they sufficiently contiguous to be considered a separate physiographic province, but where they do appear they are distinctive from the surrounding bedrock geology and other physiographic attributes. The Culpeper Basin is characterized by a nearly flat sediment-filled basin interspersed by a system of intrusions consisting of weather-resistant dikes. Specifically, the bedrock in the project site area consisted of Siltstone and Shale of Midland Formation. 3.2 Soil Stratification The subsurface conditions encountered at the boring locations are shown on the test boring records in the appendices. These test boring records represent our interpretation of the subsurface conditions based on visual examination of field samples by a geotechnical engineer and laboratory test results of the field samples. The lines designating the interfaces between various strata on the test boring records represent the approximate interface locations. The actual transitions between strata may be gradual, abrupt or slightly different depths. In general, the subgrade soils consisted of 2 inches of topsoil underlain by a layer of clay overlaying siltstone bedrock except for Boring B-1, where sand and gravel was encountered below the topsoil. Specifically, four (4) idealized strata can be classified at the project site: DMYGEO

9 Stratum I: Brown Lean Clay (CL) This stratum was encountered below the top soil in B-2 and B-3. The Standard Penetration Test (SPT) resistances ranged from 5 to greater than 7 blows per foot (bpf). The moisture content was approximately 25 percent. Stratum II: Gray High Plasticity Clay (CH) This stratum was encountered below the Stratum I soil to the bedrock. The SPT resistances ranged from 8 to over 50 blows of 5-inch penetration. The moisture content was approximately 31percent. Stratum III: Brown Clayey Gravel (GC) This stratum was encountered in B-1 below the topsoil. The SPT resistances ranged from 3 to over 50 blows of 4-inch penetration. The moisture content was approximately 16 percent. Stratum IV: Midland Siltstone Bedrock (SLS) Top elevation of the bedrock varied between 7.5 feet in B-1 and 12.5 feet in B Groundwater Groundwater was encountered at approximately 6 feet below the ground surface in B-1 and B-3. The groundwater conditions observed, or lack thereof, reflect the conditions at the time of our exploration only. The highest groundwater levels are normally encountered in late winter and early spring. Fluctuations of the groundwater table should be expected to occur both seasonally and annually due to variations in rainfall, evaporation, transpiration, construction activity, and other site-specific factors. 3.4 Seismic Site Classification Based on the soil information obtained during our explorations, in reference to International Building Code (IBC) Section 1613 (2012), we recommend Site Class C be used for seismic design. DMYGEO

10 Section 4 Engineering Recommendations 4.1 Bridge Foundation The proposed bridge will be a 70-foot long by 14-foot wide Continental Connector Bridge with WX Steel Finish. It is estimated that a uniform load of 90 psf (LRFD) and a live load of 10,000 lbs. will be supported by the bridge foundation. In general, the existing rock is suitable to support the proposed bridge structure. Based on our understanding of the project, we recommend two options for the bridge foundation. Option 1 Shallow Foundation We do not have the details of the bridge design information. Assuming the earth excavation is applicable, the bridge can be supported by spread footing bearing on the slightly weathered bedrock. A maximum bearing pressure of 20 ksf is recommended for the foundation design (LRFD). If overturning forces are large, drilled-in rock anchors should be considered to control uplift of the heel of the shallow foundation rather than increasing foundation dimensions. Option 2 Drilled Shafts Drilled Shafts could provide flexible layout choice for the structural design. Assuming a 30-inch-diameter drilled shaft is considered for each pier, an allowable bearing capacity of 50 tons is recommended for design. The drilled shaft should have a minimum of 3 feet of rock socket embedment to reach sound, unweathered bedrock. The requirement for the rock socket is to provide axial compression, uplift, and overturning capacities. 4.2 Retaining Wall The project could include retaining walls of variable heights for the bridge abutment. The following recommendations are presented for general information about the design and construction of the retaining wall. The amount of pressure exerted by backfill on the retaining wall depends upon the height of the wall, drainage provisions, type of backfill, and method of placing the backfill. To avoid buildup of hydrostatic pressure behind the wall, the wall should be backfilled with free draining materials such as No. 57 stone or sand & gravel containing less than five (5) percent fines by weight passing the No. 8 sieve. Surface water infiltration should also be restricted by compacting a layer of cohesive material (at least 6 inches thick) above the granular material behind the top of the wall. A layer of non-woven fabric should be installed between the aggregate/gravel or sand backfill and the cohesive material above it. DMYGEO

11 At the option of the design engineer, perforated PVC pipe drains should be incorporated along the base of the wall footing below grade to restrict the accumulation of water that would increase the lateral loads on the walls. The drains may be connected directly to catch basins or surface drains nearby. It is also recommended that the granular backfill be placed with a minimal amount of tamping and compacting. In placing the backfill material, no heavy vibratory roller should pass within five (5) feet of back of the wall. Excessive tamping or compacting the granular backfill in thin layers will increase the lateral earth pressure. Within five (5) feet of the wall, hand operated equipment such as a vibratory plate or walk behind roller should be used to compact the fill. In general, the loosely placed lift thickness for a granular backfill may be no greater than eight (8) inches. However, lift thickness for the hand-operated equipment should not exceed six (6) inches to promote suitable compaction. Lateral earth pressure coefficients for active, at rest and passive conditions and equivalent fluid pressure for active condition were estimated for recommended backfill materials. For granular backfill materials, the following earth pressure coefficients have been estimated: Friction angle φ = 35 Total unit weight γ = 135 pcf Active condition: K a = 0.27 Equivalent fluid pressure: G h = 36 pcf (active condition) At-rest condition: K o = 0.43 Passive condition: K p = 3.69 The crushed stone backfill materials should occupy a zone between the wall and a line extending upward and away from the base of the wall at a 45 o angle. These parameters do not include local or uniform surcharge loads that should be applied along portions of the retaining wall that support sidewalks, pavements, or other loading conditions not typically included in earth support wall design calculations. Since the bedrock is shallow, we recommend that the retaining wall foundation be supported by the bedrock or by compacted crushed stone over bedrock. DMYGEO

12 Section 5 Construction Considerations 5.1 General The construction of the proposed bridge may require significant fill operations. In the area for the proposed fill, once the existing topsoil and other unsuitable materials are removed, the exposed subgrade soils should be observed by the Geotechnical Engineer of Record (GER). The exposed soils should be compared with those encountered in the soil test borings. Significant differences should be brought to the attention of the GER for the appropriate recommendations. Prior to the placement of engineered fill, the exposed subgrade soil should be proofrolled. Proof-rolling should be done to determine if soft zones or unsuitable soils are present that must be removed before preparing a suitable base for placement of fill. We recommend a rubber-tired, fully loaded, tandem-axle dump truck with a fullyloaded weight greater than 25 tons be used for performing proof-rolling operations. In case of local soft, loose, or unsuitable soils, such as high organic content materials are encountered, they should be completely removed or stabilized with a layer of geotextile (filter cloth) placed on the unstable foundation may be effective as a separating membrane to help support the subsequent fill construction. Fill material obtained on- or off-site should meet the requirements indicated in Table 6-1 below. When practical, requests to use soils that do not precisely meet requirements may be evaluated by the geotechnical engineer. TABLE 5-1 Fill Material Requirements Fill Material Use Under Structures, Foundations, and Under Paved Sections, or as Backfill General Site Grading Recommended USCS Material Classifications GW, GP, GC, GM, SW, SP, SC, SM, CL, & ML GW, GP, GC, GM, SW, SP, SC, SM, CL, ML, CH, & MH Index Property Limitations LL 40 & PI 25 None The maximum particle size of fill material should be less than three inches largest dimension, except in the uppermost lift of fill, where the maximum particle size should be less than two inches largest dimension. Maximum sized particles should not be in excess of 20 percent of the volume of the fill material and such particles shall be well distributed throughout the mass. Fill material shall not contain frozen masses of soil and shall not be placed on over-saturated, frozen, or frost-covered DMYGEO

13 subgrade. Fill material should be placed in such a way to provide positive drainage from the fill area. Fill materials should be free of organics and debris. Soil fill should be placed in maximum 8-inch-thick loose lifts and compacted to a minimum of 98 percent of its respective maximum dry unit weight and within ±2 percentage points of its optimum moisture content as determined by a standard Proctor test (ASTM D 698). Where fill materials will be placed to widen existing fills, or placed up against sloping ground, the soil subgrade should be scarified and the new fill benched or keyed into the existing material (see VDOT Road and Bridge Specification Section (h)). In confined areas such as utility trenches, portable compaction equipment and thin lifts of 3 to 4 inches will likely be required to achieve the specified degrees of compaction 5.2 Wet Weather Earthwork Note that DMY observed groundwater levels in two of the borings above the elevation of the top of weathered siltstone. Groundwater levels may fluctuate due to factors such a season, temperature, and rainfall and the like that are different from those prevailing at the time to boring observations were made. The contractor must develop a dewatering plan to control the subsurface water to permit preparation of all foundation and abutment subgrades in the dry. The engineering properties of the fill soils could be severely impacted by excessive moisture in the form of precipitation. Based on the time of year that construction takes place and the local meteorological conditions, it is anticipated that the above prescribed proof-rolling operation will cause the subgrade soils to pump and fail if construction takes place during the wetter portion of the year from April to September. Site work activities undertaken during the wetter portion of the year will require soil modification to establish a proper subgrade for additional fill placement. Depending on the construction schedule, lime, cement, or other forms of soil modification or stabilization should be considered. In general, the benefits of soil stabilization include: Increases in resilient modulus values (by a factor of 10 or more in many cases) Improvements in shear strength (by a factor of 20 or more in some cases) Continued strength gain with time, even after periods of environmental or load damage Long-term durability over decades of service even under severe environmental conditions. For a typical lime/cement stabilized soil, the unconfined compressive strength of the mixed product has been considered as the key performance factor. Typically, the lime/cement stabilized soils can have unconfined compressive strength from 100 psi to 1000 psi. DMYGEO

14 Section 6 Limitations of Liability This report has been prepared for the exclusive use of McCormick Taylor, Inc. and other team members for the project. Our conclusions and recommendations have been rendered in a manner consistent with the level of care and skill ordinarily exercised by members of the geotechnical engineering profession in the Commonwealth of Virginia at the time of our study. We make no other warranty, express or implied. Conclusions and recommendations presented in this report are based upon the available soil information, currently accepted engineering principles, and design details furnished by the client. DMY should be notified of any revisions to the scope of this project so that these revisions may be evaluated against the subsurface conditions. DMY will submit a written supplementary report to confirm the recommendations contained herein or to address changes to our recommendations. The soils encountered in the borings varied between boring locations. Other discontinuity in soil type and geology may exist, including abrupt strata changes and soil strength variations. The extent of these variations may not be fully determined from the borings or site reconnaissance. Additional variations may not become apparent until mass excavation commences. It is recommended that the owner retain the services of the DMY to observe the construction. DMYGEO

15 Project Site Fauquier County Cedar Lane Middle School SRTS DMY Project No. GEO Figure 1 Project Site Vicinity Map

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17 UNIFIED SOIL CLASSIFICATION SYSTEM Soils are visually classified by the United Soil Classification System (USCS) on the boring logs presented in this report. Grain size analysis and Atterberg limits tests are often performed on selected samples to aid in classification. The classification system in briefly outline on this chart. For a more detailed description of the system, see the "The Unified Soil Classification System" Corps of Engineers, US Army Technical Memorandum No (Revised April 1960) or ASTM Designation: D T COARSE - GRAINED SOILS (Less than 50% passes No. 200 sieve) FINE - GRAINED SOILS (50% or more passes No. 200 sieve) GRAVELS (50% or less of coarse fraction passes No. 4 sieve) SANDS (More than 50% of coarse fraction passes No. 4 sieve) SILTS (Limits Plot Below "A" & hatched Zone on Plasticity CLAYS (Limits Plot Above "A" & hatched Zone on Plasticity Chart) Chart) MAJOR DIVISIONS CLEAN GRAVELS (Less than 5% passes No. 200 sieve) GRAVELS WITH FINES (More than 12% passes No. 200 sieve) CLEAN SANDS (Less than 5% passes No. 200 sieve) SANDS WITH FINES (More than 12% passes No. 200 sieve) Limits plot below the "A" line & hatched zone on plasticity chart Limits plot below the "A" line & hatched zone on plasticity chart Limits plot below the "A" line & hatched zone on plasticity chart Limits plot below the "A" line & hatched zone on plasticity chart SILTS OF LOW PLASTICITY (Liquid Limit less than 50) SILTS OF HIGH PLASTICITY (Liquid Limit more than 50) CLAYS OF LOW PLASTICITY (Liquid Limit less than 50) CLAYS OF HIGH PLASTICITY (Liquid Limit more than 50) GROUP SYMBO GW GP GM GC SW SP SM SC ML MH CL CH TYPICAL NAMES Well graded gravels, gravel-sand mixtures, or sand-gravel-cobble mixtures. Poorly graded gravels, gravel-sand mixtures, or sand-gravel-cobble mixtures. Silty gravels, gravel-sand-silt mixtures. Clayey gravels, gravel-sand-clay mixtures. Well graded sands, gravelly sands. Poorly graded sands, gravelly sands. Silty sands, sand-silt mixtures. Clayey sands, sand-clay mixtures. Inorganic silts, non-plastic or slightly plastic. Inorganic silts, micaceous or diatomaceous silty soils, elastic silts. Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays. Inorganic clays of high plasticity, fat clays, sandy clays of high plasticity. NOTE: Coarse grained soils with between 5% & 12 % passing the No. 200 sieve and fine grained soils with Atterberg limits plotting in the hatched zone on the plasticity chart shall have dual symbol. In Arizona, local streams contain sand, gravel & cobble type material, which are locally known as SGC or riverrun material. THe USCS is not used to divide and symbolize the material. 60 PLASTICITY CHART DEFINITIONS OF SOIL FRACTIONS SOIL COMPONENT PARTICLE SIZE RANGE PLASTICITY INDEX (PI) CH or OH CL or OL MH or OH CL-ML ML or OL LIQUID LIMIT (LL) Cobbles Gravel Sand Fines Above 3 in. 3 in. to No. 4 sieve Coarse gravel 3 in. to 3/4 in. Fine gravel 3/4 in. to No. 4 sieve No. 4 to No. 200 Coarse No. 4 to No. 10 Medium No. 10 to No. 40 Fine gravel No. 40 to No. 200 (silt & clay) Below No. 200 sieve Clay Smaller than 2 microns Colloid Smaller than 5 microns

18 DMY Inc Midlothian Turnpike, Suite 230 Midlothian, VA Descriptions of Soil (Unified Soil Classification System) PARTICLE SIZE IDENTIFICATION RELATIVE PROPORTIONS Description Percent by Weight (%) Description Size Trace 0-5 Boulders Diameter: 12 inches or larger Few 5-10 Cobbles Diameter: 3 to 12 inches Little Gravel Coarse - 3/4 to 3 inches Some Fine - 3/4 to No. 4 And Sand Coarse - No. 10 to No. 4 (Diameter of pencil lead) MOISTURE CONDITIONS Medium - No. 40 to No. 10 (Diameter of broom straw) Description Criteria Fine - No. 200 to No. 40 Dry Absence of moisture, (Diameter of human hair) dusty, dry to the touch Silt and Clay Passing No. 200 Moist Damp but no visible (Cannot see particles) water Wet Visible free water, usually soil is below water table COHESIVE SOILS (Silt and Clay) CONSISTENCY PLASTICITY Description Blows/ft Degree of Plasticity Plasticity Index Very Soft 2 None 0-4 Soft 3-5 Slight 5-7 Medium Stiff 6-9 Medium 8-22 Stiff High to Very High Over 22 Very Stiff Hard >31 COHESIONLESS SOIL (Sand, Gravel, and larger) RELATIVE DENSITY Description Blows/ft Description Blows/ft Very Loose <4 Dense Loose 4-10 Very Dense >50 Medium Dense 11-30

19 DEPTH (ft) 0 ELEVATION (ft) SOIL STANDARD PENETRATION HAMMER BLOWS FIELD DATA SOIL RECOVERRY (%) SAMPLE LEGEND Midlothian Turenpike Suite 300 Midlothian, VA (804) SAMPLE INTERVAL CORE RECOVERTY (%) ROCK DIP* ROCK QUALITY DESIGNATION STRATA JOINTS STRATA LEGEND PROJECT #: LOCATION: STRUCTURE: STATION: LATITUDE: SURFACE ELEVATION: Date (s) Drilled: Drilling Method (s): SPT Method (s): Other Test (s): Driller: Logger: Cedar Lee Middle School SRTS Fauquier County, Virginia Bridge 38 34'29.28"N 84 feet 3/19/ " HAS Automatic Hammer Fishburne Drilling Jeremy GROUND WATER Groundwater Encountered at 6.0 Feet No Long Term Measurements Taken FIELD DESCRIPTION OF STRATA 2" TOPSOIL B-1 PAGE 1 OF 1 OFFSET: LONGITUDE: '16.98"W COORD.DATUM: LAB DATA LIQUID LIMIT LL PLASTICITY INDEX PI MOISTURE CONTENT (%) Brown Clayey GRAVEL (GC) with Sand, Loose, Dry /4 8 Weathered SILTSTONE 9 Boring Terminated 8.2 Feet REMARKS: Boring Backfilled upon completion PAGE 1 OF 1 B-1

20 DEPTH (ft) 0 ELEVATION (ft) SOIL STANDARD PENETRATION HAMMER BLOWS FIELD DATA SOIL RECOVERRY (%) SAMPLE LEGEND Midlothian Turenpike Suite 300 Midlothian, VA (804) SAMPLE INTERVAL CORE RECOVERTY (%) ROCK DIP* ROCK QUALITY DESIGNATION STRATA JOINTS STRATA LEGEND PROJECT #: LOCATION: STRUCTURE: STATION: LATITUDE: SURFACE ELEVATION: Date (s) Drilled: Drilling Method (s): SPT Method (s): Other Test (s): Driller: Logger: Cedar Lee Middle School SRTS Fauquier County, Virginia Bridge 38 34'28.74"N 3/19/ " HAS Automatic Hammer Fishburne Drilling Jeremy GROUND WATER No Groundwater Encountered No Long Term Measurements Taken FIELD DESCRIPTION OF STRATA 2" TOPSOIL B-2 PAGE 1 OF 1 OFFSET: LONGITUDE: '16.01"W COORD.DATUM: LAB DATA LIQUID LIMIT LL PLASTICITY INDEX PI MOISTURE CONTENT (%) Brown CALY (CL) with Sand, Trace of Gravel, Medium Stiff, Dry Grayish-Brown High- Plasticity CLAY (CH), Trace of Sand and Gravel, Moist /3 10 Weathered SILTSTONE 11 Boring Terminated at Feet REMARKS: Boring Backfilled upon completion PAGE 1 OF 1 B-2

21 DEPTH (ft) 0 ELEVATION (ft) SOIL STANDARD PENETRATION HAMMER BLOWS FIELD DATA SOIL RECOVERRY (%) SAMPLE LEGEND Midlothian Turenpike Suite 300 Midlothian, VA (804) SAMPLE INTERVAL CORE RECOVERTY (%) ROCK DIP* ROCK QUALITY DESIGNATION STRATA JOINTS STRATA LEGEND PROJECT #: LOCATION: STRUCTURE: STATION: LATITUDE: SURFACE ELEVATION: Date (s) Drilled: Drilling Method (s): SPT Method (s): Other Test (s): Driller: Logger: Cedar Lee Middle School SRTS Fauquier County, Virginia Bridge 38 34'29.30"N 3/19/ " HAS Automatic Hammer Fishburne Drilling Jeremy GROUND WATER Groundwater Encountered at 6.4 Feet No Long Term Measurements Taken FIELD DESCRIPTION OF STRATA 2" TOPSOIL B-3 PAGE 1 OF 1 OFFSET: LONGITUDE: '16.55"W COORD.DATUM: LAB DATA LIQUID LIMIT LL PLASTICITY INDEX PI MOISTURE CONTENT (%) Brown CALY (CL) with Sand, Trace of Gravel, Medium Stiff, Moist Grayish-Brown High- Plasticity CLAY (CH), Trace of Sand and Gravel, Dry / Weathered SILTSTONE 14 Boring Terminated at 14.0 Feet 15 REMARKS: Boring Backfilled upon completion PAGE 1 OF 1 B-3

22 80 CL CH 60 PLASTICITY INDEX B-1 B-2 CL-ML ML LIQUID LIMIT PLOTTED DATA REPRESENTS SOIL PASSING NO. 40 SIEVE Specimen LL PL PI Fines Description 2.0 ft 4.0 ft Testing Lab RICH RICH MH CLAYEY GRAVEL WITH SAND (GC), contains rock fragments, dark brown (Visual) SANDY FAT CLAY (CH), brown and gray (Visual) B ft RICH SANDY LEAN CLAY (CL), brown and gray (Visual) ATTERBERG_LIMITS TASK 15 LAB DATA.GPJ SCHNABEL DATA TEMPLATE 2008_04_22.GDT 3/27/15 ATTERBERG LIMITS Project: Cedar Lee Middle School SRTS Fauquier County, VA GEO Contract: Task 15

23 Summary Of Laboratory Tests Appendix A Sheet 1 of 1 Project Number: Task 15 Boring No. Sample Depth ft Elevation ft Sample Type Description of Soil Specimen Testing Laboratory Natural Moisture (%) Liquid Limit Plastic Limit Plasticity Index B Jar CLAYEY GRAVEL WITH SAND (GC), contains rock fragments, dark brown (Visual) RICH DYNAMIC LAB SUMMARY TASK 15 LAB DATA.GPJ SCHNABEL DATA TEMPLATE 2010_02_25.GDT 3/27/15 B-2 B-3 Notes: Jar Jar SANDY FAT CLAY (CH), brown and gray (Visual) RICH SANDY LEAN CLAY (CL), brown and gray (Visual) RICH Soil tests in general accordance with ASTM standards. 2. Soil classifications are in general accordance with ASTM D2487(as applicable), based on testing indicated and visual classification. 3. Key to abbreviations: NP=Non-Plastic; -- indicates no test performed Project: Cedar Lee Middle School SRTS Fauquier County, VA GEO