w w w. e t t l i n c. c o m

Transcription

1 Inc. GEOTECHNICAL MATERIALS ENVIRONMENTAL DRILLING LANDFILLS March 16, 2010 Nathan D. Underwood Schaumburg & Polk, Inc. 320 S. Broadway Ave., Ste. 200 Tyler, Texas SUBJECT: Osborn Site Development Winona, Texas Geotechnical Investigation ETTL Job No. G Dear Mr. Underwood: Submitted herein is the report summarizing the results of a geotechnical investigation conducted at the site of the above referenced project. If you have any questions concerning this report, or if we can be of further assistance during construction, please contact us. We are available to perform any construction materials testing and inspection services that you may require. Thank you for the opportunity to be of service. Sincerely, Inc. James Griffith, P.G. Project Manager C. Brandon Quinn, P.E., P.G. Vice President Manager of Engineering Services Distribution: (2) Nathan D. Underwood March 16, Beech Street 1717 East Erwin 707 West Cotton Street Texarkana, Arkansas Tyler, Texas Longview, Texas Phone Phone Phone Fax Fax Fax w w w. e t t l i n c. c o m

2 Geotechnical Investigation Osborn Site Development Winona, Texas Submitted to Nathan D. Underwood Schaumburg & Polk, Inc. 320 S. Broadway Ave., Ste. 200 Tyler, Texas Prepared by Inc. Tyler, Texas March 2010

3 EXECUTIVE SUMMARY This Executive Summary is provided as a brief synopsis of the specific recommendations and design criteria provided in the attached report. It is not intended as a substitute for a thorough reading of the report in its entirety. Project Description The project will consist of a new one story building approximately 7,500 sq. ft. with associated parking. At time of drilling, uncontrolled fill had been placed for a building pad. The building pad is approximately 4 feet thick on the east side, and approximately 2 feet thick on the west. Site Description The site is relatively open at the time of drilling, with a building pad already constructed. The site generally slopes from west to east, with drainage towards the railroad tracks located to the east of the proposed site. State Highway 155 is located on the west side of the proposed site. Depth & Number of Borings 2-20 deep for the building 2 5 deep for parking Soils Encountered Surficial 3 to 5 feet of medium stiff to very stiff sandy lean clay (CL) overlying loose to dense clayey sand (SC) followed by loose to stiff sandy lean clay (CL) and loose clayey sand (SC) to depth of termination. Loose sandy silt (ML) found from 3 5 feet in boring B-3. Atterberg Plasticity Indices range from 10 to 17. Groundwater Depth Predicted to be 6 deep Recommended Foundation Type Shallow spread footings Allowable Gross Bearing Pressure 1,500 psf for isolated footings or 1,000 psf for strip footings. Footings should be founded at a minimum depth of 2 feet in properly compacted select fill or firm native soils. Floor System Flat slab on prepared subgrade Building Subgrade Preparation Remove surficial vegetation and loose topsoil. Cut to proposed subgrade as required. Scarify the exposed subgrade and recompact. Place select fill to finished slab subgrade. Geotechnical Investigation ETTL Job No. G Page i

4 Pavement Scarify and recompact subgrade. Place asphalt or concrete surface as detailed below: Type Flexible HMAC Full Depth HMAC Table 1 - Pavement Options Light Duty 2 Surface (Type D) 2 Surface (Type D) Base/Surface Thickness 6 Crushed Stone Base 3 HMAC Base (Type A or B) Concrete 5 No Base Required Type Flexible HMAC Full Depth HMAC Table 2 - Pavement Options Medium Duty 3 Surface (Type C or D) 2 Surface (Type C or D) Base/Surface Thickness 8 Crushed Stone Base 4 HMAC Base (Type A or B) Concrete 6 No Base Required Geotechnical Investigation ETTL Job No. G Page ii

5 TABLE OF CONTENTS EXECUTIVE SUMMARY... i 1.0 INTRODUCTION PROJECT DESCRIPTION SITE DESCRIPTION FOUNDATION SOIL STRATIGRAPHY & PROPERTIES Regional Geology Uncontrolled Fill Seismic Design Parameters Liquefaction GROUNDWATER OBSERVATIONS FOUNDATION DESIGN RECOMMENDATIONS Shallow Spread Footings FLOOR SYSTEMS Flat Slab BUILDING SUBGRADE PREPARATION CONSTRUCTION CONSIDERATIONS PAVEMENT RECOMMENDATIONS Pavement Subgrade Preparation Light-Duty Pavements Flexible Pavement Full Depth Asphalt Rigid Pavement Medium-Duty Pavements Flexible Pavement Full Depth Asphalt Rigid Pavement GENERAL CONSTRUCTION CONSIDERATIONS Shallow Footings Site Design Select Fill LIMITATIONS... 9 I.0 FIELD OPERATIONS II.0 LABORATORY TESTING Plate I: Plan of Borings Log of Borings with Laboratory Test Data Key to Soil Classification & Symbols APPENDIX Geotechnical Investigation ETTL Job No. G Page iii

6 1.0 INTRODUCTION This study was performed at the request and authorization to proceed granted by Nathan D. Underwood of Schaumburg & Polk, Inc., Tyler, Texas in accordance with our proposal dated February 15, Field operations were conducted on March 5, The purpose of this investigation was to define and evaluate the general subsurface conditions at 528 Main Street, Winona, Texas. Specifically, the study was planned to determine the following: Subsurface stratigraphy within the limits of exploratory borings; Classification, strength, expansive properties, and compressibility characteristics of the foundation soils; Suitable foundation types and allowable loading; and, Construction related problems that may be anticipated by the investigation. To determine this information a variety of tests were performed on the soil samples. The scope of testing for this report comprised Standard Penetration, Atterberg liquid and plastic limits, Percentage of Fines Passing the No. 200 sieve, Natural Moisture Content, Pressure Swell testing and unconsolidated, undrained triaxial compression tests. These tests were conducted to classify the soil strata according to a widely used engineering classification system; identify, and provide quantitative data for active (expansive) soils; define strength characteristics relating to allowable bearing values; predict immediate settlement; and assess construction workability of the soils. The conclusions and recommendations that follow are based on limited information regarding site grading and proposed finished floor elevations provided to ETTL by others. Borings were located in the field by ETTL personnel based on a site plan provided by client. (ETTL did not confirm by survey that the locations indicated on the attached Plan of Borings accurately reflect the location on the ground). This information should be verified prior to design. Should any portion of it prove incorrect, this firm should be notified in order to assess the need for revisions to this report. 2.0 PROJECT DESCRIPTION The project will consist of a new one story building approximately 7,500 sq. ft. with associated parking. At time of drilling, uncontrolled fill had been placed for a building pad. The building pad is approximately 4 feet thick on the east side, and approximately 2 feet thick on the west. 3.0 SITE DESCRIPTION The site is relatively open at the time of drilling, with a building pad already constructed. The site generally slopes from west to east, with drainage towards the railroad tracks located to the east of the proposed site. State Highway 155 is located on the west side of the proposed site. Geotechnical Investigation ETTL Job No

7 4.0 FOUNDATION SOIL STRATIGRAPHY & PROPERTIES Surficial 3 to 5 feet of medium stiff to very stiff sandy lean clay (CL) overlying loose to dense clayey sand (SC) followed by loose to stiff sandy lean clay (CL) and loose clayey sand (SC) to depth of termination. Loose sandy silt (ML) found from 3 5 feet in boring B-3. Atterberg Plasticity Indices range from 10 to Regional Geology The Weches Formation of Eocene age outcrops at the project site. The Weches is typically composed of glauconitic silt and shale that may contain limestone interbeds and lesser quantities of quartz sand. The formation varies in color from grayish green in unweathered sections to a yellowish-reddish brown upon exposure. The thickness of the formation varies from approximately 50 to 90 feet. Commonly, vertically-oriented, iron oxide-filled joint sets are present within the upper half of the formation. Marine megafossils are ubiquitous and most prevalent in the lower half of the formation. Intensely weathered slopes generally result in the formation of pronounced scarps due to the resistant nature of the formation. 4.2 Uncontrolled Fill Fill was reportedly placed for the building pad prior to our sampling. The process of placement is unknown and no records exist as to whether or not the placement was monitored. Our tests indicated some significant variation in the density of the fill, which could mean that differential settlement is possible. The only practical way to verify the adequacy of structural fill is through observation and testing during placement. Since this was outside the scope of our involvement, it should be understood that our recommendations are based solely on the information obtained in our borings and do not address possible deficiencies in the fill. 4.3 Seismic Design Parameters Data regarding soil type and density to a depth of 100 feet is needed to designate a design class for the profile where liquefaction potential is not considered. However, we predict that the site could be classified Class E (disregarding liquefaction considerations) based on the limited data available. Given the presence of saturated very loose to loose clayey sand in the upper 13 of the soil profile, the potential for liquefaction is believed to possibly be significant (see Section 4.4, below). Based on the 2006 International Building Code (IBC) section 1615 Earthquake Loads Site Ground Motion, the seismic site class definition should be taken as Class F, if, in fact, there is an unacceptable factor of safety against liquefaction. If the factor of safety against liquefaction is deemed acceptable, then the site class would be Class E. A seismic impact zone is an area with a 10 percent or greater probability that the maximum horizontal acceleration in rock, expressed as a percentage of the earth s gravitational pull, will exceed 0.10g in 50 years. Based on the maps and the site coefficients determined for site class E contained in the IBC, parameters as listed below are recommended by the Code: Site Coefficients: F a = 2.50* F v = 3.50* Geotechnical Investigation ETTL Job No

8 Maximum Earthquake Spectral Response Acceleration Parameters: S MS = 0.342* S M1 = 0.208* Design Spectral Response Acceleration Parameters: S DS = 0.228* S D1 = * * - requires special consideration of the structure characteristics to determine appropriate values when the site is classed F. 4.4 Liquefaction Liquefaction is a phenomenon where soil pore pressure builds up rapidly during cyclic loading causing a loss of shear strength and consequent significant ground movement both laterally and vertically. In layman s terms the soil turns into quick sand, losing ability to support load, and can spread laterally out from under foundations. Foundations sitting on sand that liquefies during an earthquake can sink into the soil. Recent research 1, 2 has shown that liquefaction potential exists not only in relatively clean sands, but also, under certain circumstances, in sands, silts and clayey soils of low plasticity (PI<12 or up to 20 if MC>0.85*Liquid Limit) with significant fines content. In order for liquefaction to be triggered, the water content of finer soils needs to be high (generally > 80-85% of the Liquid Limit) and the density relatively low (assessed in terms of the SPT blow count generally where N1 (SPT Value normalized for overburden pressure) is low). In addition, the frequency and magnitude of ground shaking has to reach a certain threshold, which is related to the soil properties and local geology. The insitu soils below the surficial clays consist of saturated silty sands and clayey sands of low density down to a depth of about 13. These characteristics indicate that there is some potential for liquefaction as well as for seismic settlement. Standard simplified evaluation of liquefaction potential such as that found in the method set forth in Geotechnical Engineering Circular No. 3, Earthquake Engineering for Highways Vol 1 Design Principals, Publication No. FHWA-SA , Federal Highway Administration, is for peak ground accelerations above 0.2g. Since the peak ground acceleration is less than that for this site, the evaluation using this method is somewhat questionable (the FHWA document gives no guidance for peak acceleration less than 0.2g). However, a detailed study to ascertain more definitively both the potential for liquefaction and the impact on the structure would be quite involved and is outside the scope of this study. 5.0 GROUNDWATER OBSERVATIONS Groundwater levels and seepage depths were monitored during and upon completion of drilling as well as at some point following completion. Seepage was encountered at 6 feet deep. Groundwater depth was measured at 6 feet deep after completion of drilling. The phreatic surface is predicted to be 6 feet deep. 1 Idriss, I.M. and Boulanger, R.W., Semi Empirical Procedures for Evaluating Liquefaction Potential During Earthquakes, Invited Paper, 11th International Conference on Soil Dynamics and Earthquake Engineering, Berkley, CA, January Seed, R. B., et al, Recent Advances in Soil Liquefaction Engineering: A Unified and Consistent Framework, 26th Annual ASCE Los Angeles Spring Seminar, April Geotechnical Investigation ETTL Job No

9 It should be noted, however, that seasonal groundwater conditions might vary throughout the year depending upon prevailing climatic conditions. This magnitude of variance will be largely dependent upon the duration and intensity of precipitation, surface drainage characteristics of the surrounding area, and significant changes in site topography. 6.0 FOUNDATION DESIGN RECOMMENDATIONS Individual and/or continuous shallow spread footings are recommended for support of the proposed superstructure loads. Pertinent design parameters and guideline considerations for this system are presented below. Proper site design that prevents water from soaking into the subgrade soils around the buildings is essential to reduce the potential for excessive movement caused by saturation of foundation soils. 6.1 Shallow Spread Footings Footings should be designed to bear in undisturbed native soil or properly compacted select fill at a minimum depth of 2 feet below the finished slab subgrade or adjacent exterior grade (whichever is deeper). Isolated footings should have a minimum width of 3 feet and strip footings should be at least 12 inches wide. Footings should be proportioned for allowable gross bearing pressures of 1,500 psf for individual (isolated) footings and 1000 psf for continuous (strip) shallow footings. These allowable pressures incorporate a safety factor relative to shear failure of the soil of at least 3 and may be increased up to 33% for intermittent loads such as wind. Predicted total settlement due to dead load pressure (assumed to be 1,500 psf) for footing widths less than 5 feet is less than 1 inch (total) and 0.5 inch (differential) 7.0 FLOOR SYSTEMS The floor system for use with a shallow spread footing system consists of a flat slab that is either monolithic with, or isolated from, shallow footings. 7.1 Flat Slab This floor system consists of a cast-in-place concrete, unstiffened, flat slab on prepared subgrade (according to section 8.0 BUILDING SUBGRADE PREPARATION, below), which is placed monolithically with shallow footings, or can be isolated from them. Provision should be made to account for the fact that a heavily loaded foundation element, which is monolithic with an unloaded slab, may result in significant stress in the transition zone between the unloaded slab and the foundation element. Reinforcing in the slab is used primarily to control shrinkage. 8.0 BUILDING SUBGRADE PREPARATION In order to validate the design assumptions given above regarding allowable foundation loads, and, in order to provide a serviceable floor system (within the limitations stated above), it is imperative that the subgrade of the building be properly prepared. The following procedures are recommended as a minimum: Geotechnical Investigation ETTL Job No

10 Remove surficial vegetation and topsoil. Cut to proposed subgrade. Verify that all stump holes are backfilled with properly compacted select fill. Scarify the exposed subgrade to a depth of 6 inches, adjust the moisture content to, and maintain it within a range of optimum 1% to optimum +3 percent and recompact to a minimum density of 95% of the maximum density defined by ASTM D 698 (Standard Proctor). Place select fill to finished slab subgrade. Specifications for the placement of select fill are covered in section 11.3 Select Fill. A durable moisture barrier should be provided between the concrete building slab and the underlying soil subgrade. An intact membrane installation with lapped and sealed joints and which is repaired if damaged during construction will help to inhibit moisture migration from the subgrade through the slab. 9.0 CONSTRUCTION CONSIDERATIONS Surficial loose sand in some areas may become unstable when wet necessitating stabilization or removal and replacement of wet soils to facilitate construction. The extent of this work is a determination best based on conditions at the time of construction PAVEMENT RECOMMENDATIONS General recommendations for the design of minimal pavement structures are provided herein for your information. A more detailed pavement analysis would require additional laboratory tests on bulk samples of the materials to be used in pavement construction and is beyond the scope of this investigation. These recommendations are based on surface soil characteristics inferred from the borings drilled for the building and at the areas to be paved. Both flexible and rigid pavement sections are presented Pavement Subgrade Preparation As a minimum, strip the native subgrade to remove topsoil and other deleterious materials. Cut to the proposed subgrade elevation as required. Exposed subgrade should be proof rolled prior to compaction in accordance with TxDOT Item 216 with the exception of roller size. The use of a 20 ton pneumatic roller or a fully loaded dump truck is recommended. Unstable areas will need to be cut out and replaced with select fill. Scarify the exposed subgrade to a depth of 6 inches, adjust the moisture content to within a range of optimum 1% to optimum +3%, and recompact to a minimum of 95% of the density as defined by ASTM D 698 (Standard Proctor). Fill material required to achieve final grade in paving areas should be selected and placed in accordance with section 11.3 Select Fill with the exception that only the soil in the top two feet of finished subgrade need meet the material requirements for select fill. Positive surface drainage should be provided during construction (especially in low areas) to maintain pavement subgrade in a dry and stable condition. Islands and irrigated areas adjacent to pavement edges can be a source of pavement Geotechnical Investigation ETTL Job No

11 problems, especially where travel lanes (as opposed to parking spaces) are adjacent. Over watering can lead to infiltration (and consequent destabilization) of flexible base material adjacent to the area. Where a flexible pavement option is chosen, landscaped areas subject to over watering (especially sprinklered islands) should be designed to contain all irrigation water (i.e. prevent leakage out the bottom into adjacent stone base material). An alternate, but less desirable solution is to place a strip of base material in the immediate vicinity of the potential infiltration comprised of HMAC base rather than crushed stone Light-Duty Pavements Flexible Pavement The minimum pavement section (and a section commonly used) for light-duty driveways and parking areas consists of 6 inches of crushed stone base with 2 inches of hot mix asphaltic concrete (HMAC). Crushed stone base should comply with Type A, Grade 2, Item 247 of the Texas Department of Transportation (TxDOT) 1993 Standard Specifications for Construction of Highways, Streets and Bridges. Compaction of the crushed stone base should be to a minimum of 95% of ASTM D 1557 (Modified Proctor) maximum density. Asphaltic concrete surfacing should comply with the requirements of Type D, Item 340 of the TxDOT Specifications and should be compacted to a density of 94% of maximum theoretical density. The Type D mix should be produced at an asphalt content of 0.2% - 0.5% above optimum Full Depth Asphalt The minimum full depth asphalt pavement section consists of 3 inches of HMAC base course (Type B) with 2 inches of HMAC surfacing (Type D). Asphaltic concrete should comply with the requirements of Types B (fine-graded base course) and D (fine-graded surface course), Item 340 of the TxDOT Specifications and should be compacted to a density of 94% of maximum theoretical density. The type D mix should be produced at an asphalt content of 0.2% - 0.5% above optimum Rigid Pavement The performance of concrete pavement is dependent on many factors including weight and frequency of traffic, subgrade conditions, concrete quality (which itself is dependent on a host of factors), joint type and layout, jointing procedures, and numerous construction practices. A detailed discussion of all of these items is beyond the scope of this report. By way of general guidance, the following recommendations are offered: Minimum concrete compressive strength of 3,500 psi at 28 days placed with a maximum slump of 5 inches. The mix should contain 4% - 6% entrained air for durability. Minimum pavement thickness of 5 inches. Sawcut or preformed control joints at maximum spacing of 12 feet each way. Layout of joints should form basically square panels. Timing of the cutting of joints is critical to their performance and generally should be within 4-18 hours of concrete placement. Sealing of joints and cracks and maintenance of the seal are critical for satisfactory performance. Geotechnical Investigation ETTL Job No

12 Adequate site drainage to prevent ponding on or near the pavement. Cure concrete via use of liquid membrane curing compound. Concrete quality should be controlled and jointing properly executed. Minimum reinforcement should consist of 6 x 6 No. 6 welded wire fabric or No. 3 at 18 inches each way and should not be continuous through control joints. All edges of pavement should be thickened to 9 inches (transitioning back to 5 inches over a minimum distance of 3 feet). Allow a minimum of 7 days curing time before permitting traffic on the pavement. The reader is referred to the American Concrete Institute Publication No. ACI 330R, Guide for Design and Construction of Concrete Parking Lots for more detailed information Medium-Duty Pavements Flexible Pavement For areas that will be subject to trash or delivery truck parking and traffic, the minimum recommended flexible pavement section consist of 8 inches of crushed stone base and 3 inches of asphaltic concrete surfacing. The 3 inches of surfacing may be composed of finegraded surface course (Type D) or coarse-graded surface course (Type C). Paving materials should be specified as discussed previously Full Depth Asphalt For a medium-duty full depth asphalt section, the minimum recommended section is 6 inches of HMAC paving consisting of 2 inches wearing surfacing (Type D) over 4 inches of asphaltic binder (Type B). Paving materials should be specified as discussed previously Rigid Pavement Recommendations for medium-duty concrete paving are the same as for light duty except that 6 inches of portland cement concrete should be considered the minimum pavement section and the edges should be thickened to 9 inches. Type Flexible HMAC Full Depth HMAC Table 10.1 Pavement Options Light Duty 2 Surface (Type D) 2 Surface (Type D) Base/Surface Thickness 6 Crushed Stone Base 3 HMAC Base (Type A or B) Concrete 5 No Base Required Geotechnical Investigation ETTL Job No

13 Type Flexible HMAC Full Depth HMAC Table Pavement Options Medium Duty 3 Surface (Type C or D) 2 Surface (Type C or D) Base/Surface Thickness 8 Crushed Stone Base 4 HMAC Base (Type A or B) Concrete 6 No Base Required 11.0 GENERAL CONSTRUCTION CONSIDERATIONS 11.1 Shallow Footings All footing excavations should be inspected by qualified personnel to insure that subgrade is composed of firm, undisturbed native soil or properly compacted select fill as recommended in this report. Water and/or loose material in footing excavations should be removed prior to final shaping of the footing excavation and placement of concrete Site Design The following recommendations are derived from years of experience with structures founded on non-expansive soils and are considered essential to satisfactory structure performance: Sidewalks should be sloped away from the building and not tied to the structure. The ground surface around the building and the paved areas should be sloped away from the building on all sides so that water will drain away from the structure. Water should not be allowed to pond near the structure during or after rainfall events. Adequate drainage should be provided to minimize any increase in moisture content of the foundation soils. Roof drainage should be conveyed by an appropriate means at least 15 feet from the building before it is allowed to drain into the subgrade. Backfill for utility line ditches should be carefully controlled. It should be placed at a density similar to the surrounding soil. A density of 95 percent of ASTM D 698 (Standard Proctor) may be used as a rule of thumb. The top six inches under paving should be compacted to a density equal to that specified for the pavement subgrade Select Fill Select fill shall consist of homogeneous soils (i.e. not sand with clay lumps) free of organic matter and rocks larger than 6 inches in diameter. For fill beneath structures the soil should possess an Atterberg PI <18, with a liquid limit <35 and a percent passing the #200 sieve <60%. Atterberg limits testing of the fill at a rate of 1 test per 500 cubic yards of fill (minimum 1 test per lift and as visual change occur) placed is recommended to verify that fill specifications are met. The material should be placed in the following manner Prepare the subgrade in accordance with the recommendations discussed in a Geotechnical Investigation ETTL Job No

14 previous section of this report entitled BUILDING SUBGRADE PREPARATION. Sites that slope more than about 15% should be benched with 5-foot wide benches prior to placing fill. Place subsequent lifts of select fill in thin, loose layers not exceeding nine inches in thickness to the desired rough grade and compact to a minimum of 95% of standard proctor density (ASTM D698) (100% for the entire fill thickness where thickness of fill at any point beneath a structure is greater than 6 ) at a moisture content within a range of optimum to optimum +3%. Conduct in-place field density tests at a rate of one test per 3,000 square feet for every lift with a minimum of 2 tests per lift. Density testing is essential to assure that the soil is properly placed. Prevent excessive loss of moisture during construction. For select fill placed above the existing groundline, extend the lateral limits of the fill at least 5 feet beyond the perimeter of the building area, transitioning back to the existing groundline on a 4:1(horizontal/vertical) slope LIMITATIONS Geotechnical design work is characterized by the presence of a calculated risk that soil and groundwater conditions may not have been fully revealed by the exploratory borings. This risk derives from the practical necessity of basing interpretations and design conclusions on a limited sampling of the subsoil stratigraphy at the project site. The number of borings and spacing is chosen in such a manner as to decrease the possibility of undiscovered anomalies, while considering the nature of loading, size and cost of the project. The recommendations given in this report are based upon the conditions that existed at the boring locations at the time they were drilled. The term "existing groundline" or "existing subgrade" refers to the ground elevations and soil conditions at the time of our field operations. It is conceivable that soil conditions throughout the site may vary from those observed in the exploratory borings. If such discontinuities do exist, they may not become evident until construction begins or possibly much later. Consequently, careful observations by the geotechnical engineer must be made of the construction as it progresses to help detect significant and obvious deviations of actual conditions throughout the project area from those inferred from the exploratory borings. Should any conditions at variance with those noted in this report be encountered during construction, this office should be notified immediately so that further investigations and supplemental recommendations can be made. This company is not responsible for the conclusions, opinions, or recommendations made by others based on the contents of this report. The recommendations made in this report are applicable only to the proposed structure(s) as defined in SECTION 2.0 PROJECT DESCRIPTION. The purpose of this study is only as stated elsewhere herein and is not intended to comply with the requirements of 30 TAC 330 Subchapter T regarding testing to determine the presence of a landfill. Our professional services have been performed, our Geotechnical Investigation ETTL Job No

15 findings obtained, and our recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices. No warranties are either expressed or implied. Geotechnical Investigation ETTL Job No

16 APPENDIX I.0 FIELD OPERATIONS Subsurface conditions were defined by 4 sample core borings drilled to depths of 5 feet and 20 feet. Borings were staked by ETTL personnel based on a site plan provided by client. The field boring logs were prepared as drilling and sampling progressed. The final boring logs are also included in the Appendix. Descriptive terms and symbols used on the logs are in accordance with the Unified Soil Classification System (ASTM D 2487). A reference key is provided on the final page of this report. A truck-mounted drill rig utilizing dry auger drilling procedures was used to advance the borings. Soils were sampled by means of a 1 3/8-inch I.D. by 24-inch long split-spoon sampler driven into the bottom of the borehole in accordance with ASTM D 1586 procedures. In conjunction with this sampling technique, the Standard Penetration Test was conducted by recording the N-value, which is the number of blows required by a 140-pound weight falling 30 inches to drive a split-spoon sampler 1 foot into the ground. For very dense strata, the number of blows is limited to a maximum of 50 blows within a 6-inch increment. Where possible, the sampler is "seated" six inches before the N-value is determined. The N-value obtained from the Standard Penetration Test provides an approximate measure of the relative density that correlates with the shear strength of soil. The disturbed samples were removed from the sampler, logged, packaged, and transported to the laboratory for further identification and classification. Soils were also sampled by means of a 3-inch O.D. by 24-inch long thick-walled Shelby Tube sampler. Using the drilling rig's hydraulic pressure, the sampler was pushed smoothly into the bottom of the borehole. The consistency of these samples was measured in the field by a calibrated pocket penetrometer. These values, recorded in tons per square foot, are shown on the boring logs. Such samples were extruded in the field, logged, sealed to maintain in situ conditions, and packaged for transport to the laboratory. All boreholes were backfilled with cuttings after collecting final groundwater readings. Samples obtained during our field studies and not consumed by laboratory testing procedures will be retained in our Tyler office free of charge for a period of 60 days. To arrange storage beyond this point in time, please contact the Tyler office. II.0 LABORATORY TESTING Upon return to the laboratory, a geotechnical engineer visually examined all samples and several specimens were selected for representative identification of the substrata. By determining the Atterberg liquid and plastic limits (ASTM D 4318) and percentage of fines passing the No. 200 sieve (ASTM D 1140), field classification of the various strata was verified. Also conducted were natural moisture content tests (ASTM D 2216). Pressure-swell testing (ASTM D 4546 Methods A & B (mod)) was performed by adding moisture to a specimen and observing the amount of pressure necessary to restrain swelling. In some cases (see report) the specimen is dried from its natural moisture content to evaluate the potential swell of dry soils. The restraining pressure is removed and the

17 amount of swell under this condition is recorded. These results are presented in the individual log of boring provided in this Appendix. Strength characteristics of the cohesive substrata were evaluated by conducting unconsolidated, undrained triaxial compression tests (ASTM D 2850) on selected undisturbed field samples obtained with the Shelby tube sampler. In this type of compression test, confining pressures were chosen that approximate in situ pressures at the sample depth below existing ground. The specimens were axially loaded until failure occurred. The shear strength (or cohesion) is equal to one-half the peak compressive stress. Moisture content (ASTM D 2216) and dry density (ASTM D 2437) are determined as part of this test. The results of these tests are also presented in the individual log of boring provided in this Appendix.

18

19 DEPTH (ft) 0 SAMPLES USC CL GEOLOGIC UNIT WATER LEVEL ETTL ENGINEERS & CONSULTANTS MAIN OFFICE 1717 East Erwin Tyler, Texas (903) MATERIAL DESCRIPTION PROJECT: S&P Osborn Site Development Winona, Texas PROJECT NO.: G FIELD STRENGTH DATA BLOW COUNT Qu (tsf) PPR (tsf) Torvane (tsf) LOG OF BORING B-1 BORING TYPE: Hand Auger DRY DENSITY (pcf) COMPRESSIVE STRENGTH (tsf) FAILURE STRAIN (%) CONFINING PRESSURE (psi) Plastic Limit Natural Moisture Content and Atterberg Limits Moisture Content ATTERBERG LIMITS(%) LL PL SANDY LEAN CLAY(CL) medium stiff; brown N= Sieve=2%, +4 Sieve=2% Ew Liquid Limit DATE 3/5/10 SURFACE ELEVATION MOISTURE CONTENT (%) LIQUID LIMIT PLASTIC LIMIT PLASTICITY INDEX PI MINUS #200 SIEVE (%) OTHER TESTS PERFORMED (Page Ref. #) --brown and red N=4 5 Bottom of 5' Water Level Water Observations: Est.: Measured: Perched: Dry and open upon completion. Key to Abbrevations: N - SPT Data (Blows/Ft) P - Pocket Penetrometer (tsf) Notes: GPS Coordinates: N ', W ' T - Torvane (tsf) L - Lab Vane Shear (tsf)

20 DEPTH (ft) 0 SAMPLES USC CL GEOLOGIC UNIT WATER LEVEL ETTL ENGINEERS & CONSULTANTS MAIN OFFICE 1717 East Erwin Tyler, Texas (903) MATERIAL DESCRIPTION PROJECT: S&P Osborn Site Development Winona, Texas PROJECT NO.: G FIELD STRENGTH DATA BLOW COUNT Qu (tsf) PPR (tsf) Torvane (tsf) LOG OF BORING B-2 BORING TYPE: Flight Auger DRY DENSITY (pcf) COMPRESSIVE STRENGTH (tsf) FAILURE STRAIN (%) CONFINING PRESSURE (psi) Plastic Limit Natural Moisture Content and Atterberg Limits Moisture Content Liquid Limit DATE 3/5/10 SURFACE ELEVATION MOISTURE CONTENT (%) ATTERBERG LIMITS(%) LIQUID LIMIT LL PLASTIC LIMIT PL PLASTICITY INDEX PI MINUS #200 SIEVE (%) OTHER TESTS PERFORMED (Page Ref. #) SANDY LEAN CLAY(CL) stiff; red N= Sieve=1%, +4 Sieve=0% --black, brown, and red N=15 5 SC CLAYEY SAND(SC) loose; reddish brown N= Sieve=1%, +4 Sieve=0% CL SANDY LEAN CLAY(CL) medium stiff; yellow and gray N=5 10 Ew --stiff; red, gray, and tan N=9 15 SC CLAYEY SAND(SC) loose; yellow and gray N=9 20 Bottom of 20' Water Level Water Observations: Est.: Measured: Perched: Dry and open upon completion. Key to Abbrevations: N - SPT Data (Blows/Ft) P - Pocket Penetrometer (tsf) Notes: GPS Coordinates: N ', W ' T - Torvane (tsf) L - Lab Vane Shear (tsf)

21 DEPTH (ft) 0 SAMPLES USC CL GEOLOGIC UNIT WATER LEVEL ETTL ENGINEERS & CONSULTANTS MAIN OFFICE 1717 East Erwin Tyler, Texas (903) MATERIAL DESCRIPTION PROJECT: S&P Osborn Site Development Winona, Texas PROJECT NO.: G FIELD STRENGTH DATA BLOW COUNT Qu (tsf) PPR (tsf) Torvane (tsf) LOG OF BORING B-3 BORING TYPE: Flight Auger DRY DENSITY (pcf) COMPRESSIVE STRENGTH (tsf) FAILURE STRAIN (%) CONFINING PRESSURE (psi) Plastic Limit Natural Moisture Content and Atterberg Limits Moisture Content Liquid Limit DATE 3/5/10 SURFACE ELEVATION MOISTURE CONTENT (%) ATTERBERG LIMITS(%) LIQUID LIMIT LL PLASTIC LIMIT PL PLASTICITY INDEX PI MINUS #200 SIEVE (%) OTHER TESTS PERFORMED (Page Ref. #) SANDY LEAN CLAY(CL) stiff; red and gray; with iron ore N=11 ML SANDY SILT(ML) loose; brown and yellow N= Sieve=2%, +4 Sieve=0% 5 SC CLAYEY SAND(SC) very loose; tan, gray, and red N=0 10 Ew --with gravel N= Sieve=14%, +4 Sieve=8% CL SANDY LEAN CLAY(CL) stiff; gray and brown N=9 15 SC CLAYEY SAND(SC) loose; gray and brown; with coarse-grained sand; with gravel N=4 20 Bottom of 20' Water Level Water Observations: completion. Est.: Measured: Perched: Water 6' and open to 6' upon Key to Abbrevations: N - SPT Data (Blows/Ft) P - Pocket Penetrometer (tsf) T - Torvane (tsf) Notes: GPS Coordinates: N ', W ' L - Lab Vane Shear (tsf)

22 DEPTH (ft) 0 SAMPLES USC CL GEOLOGIC UNIT WATER LEVEL ETTL ENGINEERS & CONSULTANTS MAIN OFFICE 1717 East Erwin Tyler, Texas (903) MATERIAL DESCRIPTION PROJECT: FIELD STRENGTH DATA S&P Osborn Site Development Winona, Texas PROJECT NO.: G BLOW COUNT Qu (tsf) PPR (tsf) Torvane (tsf) LOG OF BORING B-4 BORING TYPE: Hand Auger DRY DENSITY (pcf) COMPRESSIVE STRENGTH (tsf) FAILURE STRAIN (%) CONFINING PRESSURE (psi) Plastic Limit Natural Moisture Content and Atterberg Limits Moisture Content Liquid Limit DATE 3/5/10 SURFACE ELEVATION MOISTURE CONTENT (%) ATTERBERG LIMITS(%) LIQUID LIMIT LL PLASTIC LIMIT PL PLASTICITY INDEX PI MINUS #200 SIEVE (%) OTHER TESTS PERFORMED (Page Ref. #) SC Ew SANDY LEAN CLAY(CL) very stiff; red; with gravel CLAYEY SAND(SC) dense; red; with sand seams P=2.5 P= *Swell 125 psf. Surcharge 5 Bottom of 5' Water Level Water Observations: Est.: Measured: Perched: Dry and open upon completion. Key to Abbrevations: N - SPT Data (Blows/Ft) P - Pocket Penetrometer (tsf) T - Torvane (tsf) L - Lab Vane Shear (tsf) Notes: GPS Coordinates: N ', W '. *Swell determined by ASTM D 4546 Method A&B (modified). Moisture Content =26% initial and 27% final. Zero Swell Pressure 875 psf.

23