GEOTECHNICAL INVESTIGATION GEOTECHNICAL INVESTIGATION FLAT CREEK WASTEWATER INTERCEPTOR GARLIC CREEK FORCE MAIN WACO, TEXAS BUDA, TEXAS

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2 GEOTECHNICAL INVESTIGATION GEOTECHNICAL INVESTIGATION FLAT CREEK WASTEWATER INTERCEPTOR GARLIC CREEK FORCE MAIN WACO, TEXAS BUDA, TEXAS G. E. WALKER & ASSOCIATES, L.L.C. LOCKWOOD, ANDREWS & NEWNAM, INC. WACO, TEXAS AUSTIN, TEXAS

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4 GEOTECHNICAL INVESTIGATION GARLIC CREEK FORCE MAIN BUDA, TEXAS Report to: LOCKWOOD, ANDREWS & NEWNAM, INC. Austin, Texas Submitted by: FUGRO CONSULTANTS, INC. September 2012

5 Report No CONTENTS PAGE INTRODUCTION... 1 AUTHORIZATION... 1 PURPOSE AND SCOPE... 1 FIELD INVESTIGATION... 2 LABORATORY TESTING... 2 Natural Water Content (ASTM D 2216)... 3 Atterberg Limit Determinations (ASTM D 4318)... 3 Sieve Analysis (ASTM D 422)... 3 Unconfined Compression Strength of Intact Rock Core Specimens (ASTM D 7012)... 3 Strata Descriptions... 3 SITE AND SUBSURFACE CONDITIONS... 4 Physiography... 4 Geology... 4 Site Stratigraphy and Engineering Properties along Alignment... 5 Groundwater Occurrence... 5 GEOTECHNICAL PARAMETERS AND CONSTRUCTION... 6 Pipe Bedding... 6 Trench Backfill... 7 Excavation Potential... 7 Temporary Trench Excavations and Support... 7 Geotechnical Conditions at Trenchless Installations... 8 CONDITIONS... 9 ILLUSTRATIONS PLATE VICINITY MAP... 1 PLAN OF BORINGS... 2 BORING LOGS KEYS TO TERMS AND SYMBOLS USED ON THE BORING LOGS... 8 & 9 GENERALIZED SUBSURFACE PROFILES AT TRENCHLESS CROSSINGS & 11

6 Report No INTRODUCTION On May 17, 2012, Fugro Consultants, Inc. (Fugro) initiated the geotechnical investigation with the drilling of five (5) borings for the proposed force main alignment extending from an existing lift station at FM 967 and Garlic Creek, south to the Wastewater Treatment Plant south of Onion Creek in Buda, Texas. The project will consist of about 5,000 linear ft of 10- to 18-inch diameter force main to be installed to depths of about 5 to 25 ft below existing grade. The force main will be installed using conventional open-cut techniques with two planned trenchless installations, one beneath FM 967 and another beneath Onion Creek. The project alignment is shown on the Vicinity Map, Plate 1. Lockwood, Andrews & Newnam (LAN), Inc. is providing the civil design services for the proposed force main. Fugro was retained by LAN, Inc. to provide geotechnical engineering services. AUTHORIZATION The geotechnical investigation was formally authorized by Ms. Julie Hastings, P.E., with LAN, Inc. with formal acceptance of the Fugro Consultants, Inc. revised proposal dated November 17, The proposal outlines the scope of services for this investigation. PURPOSE AND SCOPE The purposes of the investigation were to obtain subsurface information to identify general geotechnical and geologic conditions along the project alignment and provide limited geotechnical recommendations for earthwork and material specifications for the utility installation. This was accomplished through a three phase study including: 1) a field investigation phase for determining general subsurface conditions and obtaining representative samples for classification and testing, 2) a laboratory testing program to aid in the classification of subsurface strata and to establish engineering properties of the strata encountered, and 3) analyses of field and laboratory data to develop limited geotechnical design and construction recommendations. Field sampling, laboratory testing, soil classifications, and descriptions were in general accordance with methods, procedures, and practices set forth by the American Society for Testing and Materials Annual Book of ASTM Standards, latest edition, where applicable. -1-

7 Report No FIELD INVESTIGATION The field investigation consisted of drilling and sampling five (5) borings, designated B-1 through B-5 to depths of 10.0 to 20.0 ft below existing grade. It should be noted that the final force main profile was not provided to us during the field investigation. The approximate boring locations are shown on the Plan of Borings, Plate 2. Borings were drilled in locations that were accessible to our truck-mounted drilling equipment and clear of utilities along the proposed force main alignment. Detailed descriptions of the subsurface strata encountered at the boring locations are presented on the Logs of Borings, Plates 3 through 7. Keys to Terms and Symbols used on the boring logs are set forth on Plates 8 and 9. Pocket penetrometer values, in tons per square foot, Standard Penetration Test N-values, in blows per foot (ASTM D 1586), and Core Recovery and Rock Quality Designation (RQD) (ASTM D 6032) values, in percent, are also shown on the Logs of Borings. Latitude and longitude GPS coordinates, obtained at the boring locations using a hand-held GPS device accurate to about 3 horizontal meters, are shown on the bottom of the boring logs and should be considered approximate. The ground surface elevations at each boring location were interpolated from a 1 ft contour map provided by LAN, Inc. and are presented on the boring logs. The borings were drilled with a truck-mounted drill rig equipped with 1) continuous flight augers for advancing the holes dry and recovering disturbed samples (ASTM D 1452), 2) seamless push tubes for obtaining relatively undisturbed soil samples of cohesive strata (ASTM D 1587), 3) split-barrel samplers and drive-weight assembly for obtaining representative samples and measuring the penetration resistance (N-values) of non-cohesive soil strata (ASTM D 1586), and 4) double-tube wireline core barrels equipped with diamond and/or carbide bits for obtaining 2-inch diameter rock cores (ASTM D 2113). LABORATORY TESTING The laboratory testing program included identification and classification testing of all strata encountered in the subsurface. Soil classification tests, including Atterberg limit determinations (ASTM D 4318) and partial grain-size analyses (ASTM D 422), were conducted on representative samples of the soil strata. Unconfined compression tests (ASTM D 7012) were conducted on representative intact limestone core samples. The classification tests included natural water content determinations (ASTM D 2216). The compression tests included unit dry weight determinations. The results of the tests are tabulated on the boring logs at sample recovery depths. Brief descriptions of the test procedures are provided in the following subsections. -2-

8 Report No Natural Water Content (ASTM D 2216) Natural water content tests were performed on samples in which classification and/or strength tests were performed. Each sample was visually classified in the laboratory. Natural water contents are tabulated at sample depth on the boring logs. Atterberg Limit Determinations (ASTM D 4318) Atterberg limit tests are classification tests that determine the liquid limit and plastic limit of the soil fraction finer than the No. 40 sieve. The Atterberg limits are approximate water contents at which the soil tested behaves in a specified manner. The liquid limit is determined by measuring, in a standard device, the water content and number of blows required to close a specific width groove cut in a remolded soil sample a specified length. The plastic limit is determined by measuring the water content when threads of soil 1/8-inch in diameter begin to crumble. The plasticity index, defined as the difference between the liquid and plastic limits, indicates the degree of plasticity or the magnitude of the water content over which the soil remains plastic. Liquid limit and plasticity index values are tabulated at sample depths on the boring logs. Sieve Analysis (ASTM D 422) Grain-size characteristics of the natural soils were investigated by the determination of the percent of soil passing the Nos. 4, 40 and 200 sieves. These tests were performed by washing or sieving material through the respective sieves. The results are tabulated at sample depth on the boring logs for the percent passing the Nos. 4 and 200 sieves. Unconfined Compression Strength of Intact Rock Core Specimens (ASTM D 7012) In the unconfined compression test of intact rock core specimens, a laterally unsupported cylindrical rock specimen is loaded axially in compression to failure. The axial load is applied at a constant rate of deformation to produce failure in a test time between 2 and 15 minutes. The limestone cores tested were about 2 inches in diameter by 4 inches in length. The measured applied load at failure is recorded. Results of these tests, including unconfined compressive strength, water content, and unit dry weights, are tabulated on boring logs at core recovery depth. Strata Descriptions Descriptions of strata made in the field at the time the borings were drilled were modified in accordance with results of laboratory tests and visual examination in the laboratory. All -3-

9 Report No recovered soil samples were examined and classified in general accordance with ASTM D 2487 and described as recommended in ASTM D Rock strata were classified in general accordance with Rock Classification and Description, Chapter 1, Section 5, NAVFAC DM-7 1. Classifications of the soils and finalized descriptions of both rock and soil strata are shown on the logs of borings. SITE AND SUBSURFACE CONDITIONS Physiography The proposed Garlic Creek force main will be about 5,000 linear ft running north and south along FM 967 in Buda, Texas. From the north end of the alignment at the existing lift station at Garlic Creek with an approximate elevation of 705 ft, the topography generally slopes up to approximate elevation 736 ft at the FM 967 crossing, and then slopes down to the east and south towards Onion Creek at approximate elevation 660 ft and the existing City of Buda Wastewater Treatment Plant. Ground surface elevations along the alignment generally range from about 660 to 736 ft. Currently, land use consists of a mix of forest, pasture, and residential subdivision along the project alignment. Geology According to published geologic mapping 2, the proposed force main alignment is underlain by Alluvium and Tributary terrace deposits further underlain by the Buda Limestone formation. The Alluvium and Tributary terrace deposits consist of unconsolidated clay, gravel, sand and silt along creeks, rivers and low-lying areas (floodplains). Sand and gravel lenses and layers may be present at erratic locations within the fine-grained strata due to the depositional nature of the alluvium and terrace deposits. The contact with the underlying bedrock is erosional in nature and can vary by several feet in short distances. Large gravel, cobble and cemented layers (conglomerate) can be found within these deposits, providing challenges for excavation contractors. The granular portions of these deposits often contain groundwater. The Buda formation consists of an upper hard, resistant, fine-grained, burrowed, glauconitic, shell-fragment limestone and a lower marly, nodular, and less resistant limestone. 1 2 U.S. Navy (1971) Design Manual - Soil Mechanics, Foundations, and Earth Structures, NAVFAC DM-7. Garner, L.E. and Young, K.P. (1976), Environmental Geology of the Austin Area: An Aid to Urban Planning, Report of Investigation No. 86, Bureau of Economic Geology, The University of Texas at Austin, Plate VII (reprinted (1986). -4-

10 Report No The Buda limestone is colored with shades of tan to orange-brown that resemble discoloration caused by heating. Site Stratigraphy and Engineering Properties along Alignment The subsurface conditions along the proposed alignment can best be understood by a thorough review of the boring logs presented on Plates 3 through 7. In general, the subsurface conditions consist of surficial fat clay and clayey gravel (alluvium) underlain by tan to light bluish gray limestone of the Buda formation. Tan to brown fill material likely related to construction of the existing force mains was encountered at the Boring B-1 location. The fill material was described as tan to brown silty gravel with sand and was about 9.0 ft thick at the boring B-1 location. Standard penetration test N-values in the fill material ranged from 23 blows per foot (bpf) to 50 blows over 5 inches penetration indicating medium dense to very dense consistency. Measured liquid limits of the fill samples were 9 and 11 percent, plasticity indices were non-plastic, and percent fines (material passing the No. 200 sieve) were 11 and 14 percent. Alluvium was encountered in borings B-2, B-4, and B-5 consisting of dark brown fat clay and tan to brown clayey gravel with sand. The alluvium extended to depths of 1.0 to 10.0 ft, the termination depth in boring B-5. Standard penetration test N-values in the alluvium were 39 and 51 blows per foot (bpf) indicating dense to very dense consistency. Measured liquid limits of the alluvium samples ranged from 36 to 63 (average 54) percent, plasticity indices ranged from 17 to 37 (average 30) percent, and percent fines (material passing the No. 200 sieve) ranged from 16 to 77 (average 44) percent. Tan to light bluish gray limestone of the Buda formation was encountered in borings B-1 to B-4 at depths of 0 to 9.0 ft below the existing ground surface. The limestone was described as hard and slightly to moderately weathered with bluish-gray speckling, orange-brown staining, fossils, and discontinuities. The limestone had core recoveries of 43 to 100 (average 84) percent, and Rock Quality Designation (RQD) of 0 to 94 (average 42) percent. Unconfined compressive strengths of intact (testable) limestone core samples ranged from 33 to 520 (average 277) tsf. Groundwater Occurrence As noted on the boring logs, groundwater was encountered in boring B-5 at a depth of 9.0 ft below existing grade. The water elevation will change significantly with antecedent rainfall conditions and the water levels at nearby Garlic Creek and Onion Creek. Water was introduced -5-

11 Report No into borings B-1 to B-4 to promote the coring process; therefore, groundwater may have been present but not detected at these boring locations. Groundwater should be anticipated in excavations, particularly those extending into the sand/gravel alluvium layer immediately above the Buda limestone formation. Based on the relatively high permeability of the encountered soils, dewatering techniques will be necessary for proper force main installation. The contractor should be prepared to provide an adequate dewatering system and brace or sheet the excavation to prevent raveling, running and collapse of potential saturated granular soils. Groundwater may also be encountered within fractures and/or discontinuities in the limestone and will also requiring dewatering. GEOTECHNICAL PARAMETERS AND CONSTRUCTION Discussions regarding pipe bedding and trench backfill, as well as comments regarding excavation potential, temporary sloping, and trenchless installations are provided in the following sections. Pipe Bedding Successful installation of the 10- to 18-inch diameter HDPE pipe will depend on a number of factors including the available support from the surrounding soils and the type of bedding material used. According to the City of Austin Standard Specifications, December 2002, Section 510, coarse aggregate pipe bedding stone shall consist of clean gravel, crushed gravel or crushed limestone, free of mud, clay, vegetation, or other debris, conforming to ASTM C33 for stone quality. Size gradation may conform to ASTM C-33 No. 57 or No. 67 or the following table: Sieve Size % Passing 1½ inch inch ½ inch No No If needed for design, a modulus of soil reaction of 600 psi and 300 psi may be used for analysis and design for pipes bedded in weathered limestone and alluvium material, respectively, if the bedding material satisfies the requirements above and is placed by end dumping it into the trench. -6-

12 Report No Trench Backfill Trench excavations may be backfilled with the excavated material provided the material is processed and placed in compliance with the following: 1. Excavated trench material should be free of debris, clay lumps, excessive organics, and other deleterious material, and be screened to limit the maximum particle size to 3 inches; and 2. Compact the backfill to 95% of the maximum dry density determined using TxDOT Test Method TEX-114-E for clayey soils and TEX-113-E for gravelly soils. Compacted lift thicknesses should not be more than 6 inches. Water contents of the compacted backfill should be within ±2% of optimum. 3. Density testing should be performed on the backfill after each horizontal lift and not by potholing. This requirement will necessitate protection for the density testing technician in trenches deeper than 5 ft by some means of trench safety system. Pipe installation should not occur in trenches containing free standing water. Trenches should be dewatered using pumps and sumps, bailing, or a well-point system. Ideally, the water level should be lowered to an elevation of 2 ft below trench bottom to allow for a firm bottom upon which the bedding and pipe can be placed. Disturbed trench bottoms should be overexcavated and replaced with a lean concrete, controlled low strength material (flowable fill), or crushed limestone flexible base material to form a stable and firm trench bottom. Excavation Potential Excavation through the alluvium and fill should proceed without significant difficulty. Advancement into the limestone will proceed with greater difficulty. Based on the rock core recovery, RQD values, and measured unconfined compressive strengths of rock core samples ranging from 33 to 520 (average 277) tsf along the proposed alignment, the limestone is rippable to marginally rippable with a Caterpillar D-9, or equivalent, equipped with a multi or single shank ripper. 3 Trench excavation into the limestone will require heavy-duty excavators, rock saws, hoe rams or other similar equipment. Temporary Trench Excavations and Support Based on proposed excavations of 5 to 25 ft deep, excavations will extend through alluvium soils and into the Buda limestone formation at some locations. As discussed previously, the lower elevations of the soils just above the limestone formation may consist of saturated 3 Caterpillar Performance Handbook, 34th Edition, October 2003, published by Caterpillar, Inc., Peoria, Illinois. -7-

13 Report No granular soils which are susceptible to raveling or running into the excavation. This condition will be further complicated by the presence of groundwater. Trench safety is the sole responsibility of the contractor and he is required to retain the services of a licensed professional engineer to design his trench safety system to comply with OSHA requirements and nearby existing buried utilities. Suggestions are set forth below in accordance with OSHA 4 for classifying soil and rock encountered in our investigation. It is stressed that these are suggestions only for preliminary planning based on worst case conditions, and the actual trench safety system design is solely the contractor s responsibility. Formation OHSA Classification Recommended OSHA Slope Alluvium or Fill (CH, CL, GC, GM) Type C 1.5H to 1V* Weathered or Jointed Limestone Type A ¾H to 1V Competent Limestone Stable Rock Vertical sides** * If groundwater is encountered within the lower elevations of the alluvium (sand/gravel layer), flatter slopes of at least 2H to 1V, or a dewatering plan will be required to maintain trench safety. This flatter slope will control the sloping of the excavation and should be continued to the ground surface. ** If faulting, jointing, and/or inclined discontinuities are exposed, flatter slopes will be required to maintain safe trench excavations. Assume Type A (3/4H to 1V). Geotechnical Conditions at Trenchless Installations Two trenchless installations are planned along the proposed force main alignment at FM 967 and Onion Creek. The geotechnical conditions at these trenchless locations are presented below. FM 967. Boring B-4 was drilled at the west end of this trenchless crossing, as shown on the Generalized Subsurface Profile, Plate 10. The boring data indicates the trenchless installation will be performed within the tan limestone of the Buda formation. The trenchless operation will also be performed beneath an existing waterline. Connection with trench material from the existing waterline may allow groundwater to infiltrate. Onion Creek. Borings B-1 and B-2 were drilled at the east and west ends of this trenchless crossing, respectively, as shown on the Generalized Subsurface Profile, Plate Code of Federal Regulations Title 29 Part 1926 (2003), Labor, Occupational Safety and Health Administration, Department of Labor, Subpart P - Excavations, pgs

14 Report No The boring data indicates the trenchless installation will be performed within the tan to gray limestone of the Buda formation. Installation beneath Onion Creek may encounter scoured conditions in the limestone due to erosional and depositional processes. Contract documents should include provisions for trenchless installation through both soil and rock, and potential mixed face conditions beneath Onion Creek. For both trenchless installations, perched groundwater should be anticipated in the surficial soils above the limestone where trenchless methods will be employed. Open faults, fractures, or joints and interception with existing utility line may allow this groundwater to communicate with the pipe excavation during the installation process. The trenchless technique used should accommodate the possibility of potentially heavy localized inflows. The contractor should be prepared to deal with water pressures of up to 25 ft of head. All generated slurry and muck must be disposed of off-site in accordance with federal, state, and local laws and regulations. CONDITIONS Since some variation was found in subsurface conditions at boring locations, all parties involved should take notice that even more variation may be encountered between boring locations. Statements in the report as to subsurface variation over given areas are intended only as estimations from the data obtained at specific boring locations. It is recommended that, upon completion of the plans and specifications and the incorporation of the recommendations herein, the geotechnical engineer be retained to review such plans to ensure proper interpretation and implementation of his recommendations in the interest of the best compromise between cost and performance. The professional services that form the basis for this report have been performed using that degree of care and skill ordinarily exercised, under similar circumstances, by reputable geotechnical engineers practicing in the same locality. No warranty, expressed or implied, is made as the professional advice set forth. Fugro s scope of work does not include the investigation, detection, or design related to the presence of any biological pollutants. The term biological pollutants includes, but is not limited to, mold, fungi, spores, bacteria, and viruses, and the byproducts of any such biological organisms. The results, conclusions, and recommendations contained in this report are directed at, and intended to be utilized within, the scope of work contained in the agreement executed by Fugro Consultants, Inc. and client. This report is not intended to be used for any other purposes. -9-

15 Report No Fugro Consultants, Inc. makes no claim or representation concerning any activity or condition falling outside the specified purposes to which this report is directed, said purposes being specifically limited to the scope of work as defined in said agreement. Inquiries as to said scope of work or concerning any activity or condition not specifically contained therein should be directed to Fugro Consultants, Inc. for a determination and, if necessary, further investigation. -10-

16 P L A T E S

17 Report No GARLIC CREEK W N E S EXISTING FORCE MAIN PROPOSED FORCE MAIN ONION CREEK FM 967 MAIN ST EXISTING FORCE MAINS CR 228 IH Scale: 1" = 2000' Source: basemap provided by LAN, Inc.; aerial image obtained from Capital Area Council of Governments (CAPCOG) website (2009 Orthoimagery) VICINITY MAP Garlic Creek Force Main Buda, Texas PLATE 1

18 Report No CULLEN BLVD FM 967 B GARLIC CREEK W N S E PROPOSED FORCE MAIN B-4 B-3 PROP. BORE PITS B-2 PROP. BORE PITS FM 967 ONION CREEK B-1 GARRISON RD Scale: 1" = 800' CR 148 MAIN ST Source: basemap provided by LAN, Inc.; aerial image obtained from Capital Area Council of Governments (CAPCOG) website (2009 Orthoimagery) PLAN OF BORINGS Garlic Creek Force Main Buda, Texas PLATE 2

19 STATION: OFFSET: 10.8 L LOG OF BORING NO. B-1 Garlic Creek Force Main Buda, Texas PROJECT NO Fugro Consultants, Inc. DEPTH, FT SYMBOL SAMPLES POCKET PEN, tsf Blows/ft. REC./RQD, % N = 23 STRATUM DESCRIPTION SURF. ELEVATION: ft± Brown to tan silty GRAVEL with sand, medium dense to dense, w/fine to coarse gravel. (Fill) LAYER ELEV./ DEPTH WATER CONTENT, % 5 LIQUID LIMIT, % 9 PLASTICITY INDEX (PI), % NP PASSING NO. 4 SIEVE, % 55 PASSING NO. 200 SIEVE, % 14 UNIT DRY WEIGHT, PCF COMPRESSIVE STRENGTH TSF N = 31 5 N = NP N = 50/5" 8.9'-10' 98 / 36 10'-15' 100 / 83 Tan LIMESTONE, slightly weathered, hard, w/bluish gray-speckled layers, clay seams, orange-brown staining, fossils, and discontinuities. (Buda) - highly fractured from 9 to 10 ft (U) FUGRO STD PLATE (AUSTIN) STA ELEV GPJ FUGRO AUSTIN DATA TEMPLATE.GDT 6/25/ '-20' 100 / 94 Light bluish gray LIMESTONE, hard, w/clay seams, fossils, and discontinuities. (Buda) - high angle slickensided fracture at 19.7 ft NOTES: 1) Boring was advanced dry to the 8.9-ft depth and groundwater was not encountered above that depth prior to coring. 2) Upon completion of the coring operation, the borehole was open to 20 ft and the water level (drilling fluid) was recorded at the surface. 3) GPS coordinates - N: 30 5'16.0'', W: 97 50'43.4'' COMPLETION DEPTH: 20.0 DATE DRILLED: WATER LEVEL / SEEPAGE: See Notes UPON COMPLETION: KEY: N = Standard Penetration Test, bpf P = Pocket Penetrometer, tsf U = Unconfined Q = Unconsolidated Undrained Triaxial (U) PLATE 3

20 STATION: OFFSET: 3.9 R LOG OF BORING NO. B-2 Garlic Creek Force Main Buda, Texas PROJECT NO Fugro Consultants, Inc. DEPTH, FT SYMBOL SAMPLES POCKET PEN, tsf Blows/ft. REC./RQD, % P = 4.5+ N = 50/1" 1.1'-5' 95 / 62 STRATUM DESCRIPTION SURF. ELEVATION: ft± Brown to tan clayey GRAVEL with sand, dense, w/fine to coarse rounded gravel. GC (Alluvium) Tan LIMESTONE, slightly weathered, hard, w/bluish gray-speckled layers, clay seams, orange-brown staining, fossils, and discontinuities. (Buda) inch vugs at 1.3 ft [30% water loss during coring operation] LAYER ELEV./ DEPTH WATER CONTENT, % 10 6 LIQUID LIMIT, % 36 PLASTICITY INDEX (PI), % PASSING NO. 4 SIEVE, % PASSING NO. 200 SIEVE, % UNIT DRY WEIGHT, PCF 144 COMPRESSIVE STRENGTH TSF 113(U) 5 5'-10' 97 / (U) 10 10'-15' 99 / 61 - highly fractured from 9 to 10 ft Light bluish gray LIMESTONE, hard, w/clay seams, fossils, and discontinuities. (Buda) vertical fracture from 13 to 13.3 ft FUGRO STD PLATE (AUSTIN) STA ELEV GPJ FUGRO AUSTIN DATA TEMPLATE.GDT 6/25/ '-20' 100 / 71 - high angle slickensided fracture from 18.5 to 18.7 ft NOTES: 1) Boring was advanced dry to the 1.1-ft depth and groundwater was not encountered above that depth prior to coring. 2) Upon completion of the coring operation, the borehole was open to 20 ft and the water level (drilling fluid) was recorded at the surface. 3) GPS coordinates - N: 30 5'17.8'', W: 97 50'46.2'' COMPLETION DEPTH: 20.0 DATE DRILLED: WATER LEVEL / SEEPAGE: See Notes UPON COMPLETION: KEY: N = Standard Penetration Test, bpf P = Pocket Penetrometer, tsf U = Unconfined Q = Unconsolidated Undrained Triaxial (U) PLATE 4

21 STATION: OFFSET: 2.9 R LOG OF BORING NO. B-3 Garlic Creek Force Main Buda, Texas PROJECT NO Fugro Consultants, Inc. DEPTH, FT SYMBOL SAMPLES POCKET PEN, tsf Blows/ft. REC./RQD, % 0.1'-5' 78 / 28 STRATUM DESCRIPTION SURF. ELEVATION: ft± Tan LIMESTONE, slightly weathered, hard, highly fractured, w/clay seams, orange-brown staining, vugs, fossils, and discontinuities. (Buda) LAYER ELEV./ DEPTH WATER CONTENT, % LIQUID LIMIT, % PLASTICITY INDEX (PI), % PASSING NO. 4 SIEVE, % PASSING NO. 200 SIEVE, % UNIT DRY WEIGHT, PCF COMPRESSIVE STRENGTH TSF (U) 5 5'-10' 43 / FUGRO STD PLATE (AUSTIN) STA ELEV GPJ FUGRO AUSTIN DATA TEMPLATE.GDT 6/25/ NOTES: 1) Boring was advanced dry to the 0.1-ft depth and groundwater was not encountered above that depth prior to coring. 2) Upon completion of the coring operation, the borehole was open to 10 ft and the water level (drilling fluid) was recorded at the surface. 3) GPS coordinates - N: 30 5'28.2'', W: 97 50'49.7'' COMPLETION DEPTH: 10.0 DATE DRILLED: WATER LEVEL / SEEPAGE: See Notes UPON COMPLETION: KEY: N = Standard Penetration Test, bpf P = Pocket Penetrometer, tsf U = Unconfined Q = Unconsolidated Undrained Triaxial PLATE 5

22 STATION: OFFSET: 3.3 L LOG OF BORING NO. B-4 Garlic Creek Force Main Buda, Texas PROJECT NO Fugro Consultants, Inc. DEPTH, FT SYMBOL SAMPLES POCKET PEN, tsf Blows/ft. REC./RQD, % P = '-5' 65 / 19 STRATUM DESCRIPTION SURF. ELEVATION: ft± Dark brown fat CLAY, stiff, w/fine to coarse limestone fragments. CH (Residual Soil) Tan LIMESTONE, slightly to moderately weathered, hard, highly fractured, w/clay seams and layers, orange-brown staining, and fossils. (Buda) LAYER ELEV./ DEPTH WATER CONTENT, % LIQUID LIMIT, % PLASTICITY INDEX (PI), % PASSING NO. 4 SIEVE, % PASSING NO. 200 SIEVE, % UNIT DRY WEIGHT, PCF COMPRESSIVE STRENGTH TSF 5 5'-10' 92 / '-15' 53 / (U) FUGRO STD PLATE (AUSTIN) STA ELEV GPJ FUGRO AUSTIN DATA TEMPLATE.GDT 6/25/ '-20' 67 / 8 NOTES: 1) Boring was advanced dry to the 1.0-ft depth and groundwater was not encountered above that depth prior to coring. 2) Upon completion of the coring operation, the borehole was open to 19.5 ft and the water level (drilling fluid) was recorded at the 3.5-ft depth. 3) GPS coordinates - N: 30 5'29.3'', W: 97 50'55.1'' COMPLETION DEPTH: 20.0 DATE DRILLED: WATER LEVEL / SEEPAGE: See Notes UPON COMPLETION: KEY: N = Standard Penetration Test, bpf P = Pocket Penetrometer, tsf U = Unconfined Q = Unconsolidated Undrained Triaxial PLATE 6

23 STATION: OFFSET: 10.5 R LOG OF BORING NO. B-5 Garlic Creek Force Main Buda, Texas PROJECT NO Fugro Consultants, Inc. DEPTH, FT SYMBOL SAMPLES POCKET PEN, tsf Blows/ft. REC./RQD, % P = 4.5 STRATUM DESCRIPTION SURF. ELEVATION: ft± Dark brown fat CLAY with sand, very stiff to hard, w/trace fine to coarse rounded gravel. CH (Alluvium) - sandy w/organics from 0 to 2 ft LAYER ELEV./ DEPTH WATER CONTENT, % LIQUID LIMIT, % PLASTICITY INDEX (PI), % PASSING NO. 4 SIEVE, % PASSING NO. 200 SIEVE, % UNIT DRY WEIGHT, PCF COMPRESSIVE STRENGTH TSF P = P = 4.5+ N = 39 Brown to tan clayey GRAVEL with sand, dense to very dense, w/fine to coarse rounded gravel, and ferrous staining and nodules. GC (Alluvium) - w/angular gravel below 5.5 ft N = FUGRO STD PLATE (AUSTIN) STA ELEV GPJ FUGRO AUSTIN DATA TEMPLATE.GDT 6/25/ NOTES: 1) Boring was advanced dry to the 10.0-ft depth and groundwater was encountered at the 6.5-ft depth. 2) Upon completion of the drilling operation, the groundwater level was recorded at the 9-ft depth. 3) GPS coordinates - N: 30 5'59.1'', W: 97 50'54.6'' COMPLETION DEPTH: 10.0 DATE DRILLED: WATER LEVEL / SEEPAGE: 6.5 UPON COMPLETION: 9.0 KEY: N = Standard Penetration Test, bpf P = Pocket Penetrometer, tsf U = Unconfined Q = Unconsolidated Undrained Triaxial PLATE 7

24 TERMS AND SYMBOLS USED ON BORING LOGS FOR SOIL SOIL TYPES FAT CLAY (CH) LEAN CLAY (CL) SILT (ML) FILL Well-Graded SAND (SW) Poorly Graded SAND (SP) SILTY SAND (SM) CLAYEY SAND (SC) Well-Graded GRAVEL (GW) Poorly Graded GRAVEL (GP) SILTY GRAVEL (GM) CLAYEY GRAVEL (GC) U.S.STANDARD SIEVE 12" 3" 3/4" GRAVEL SAND BOULDERS COBBLES COARSE FINE COARSE MEDIUM FINE SOIL GRAIN SIZE IN MILIMETERS STRENGTH OF COHESIVE SOILS CONSISTENCY (2) UNDRAINED COMPRESSIVE STRENGTH Tons Per Sq. Ft. SOIL GRAIN SIZE SILT DENSITY OF GRANULAR SOILS NUMBER OF BLOWS PER FT., N CLAY RELATIVE DENSITY (2) Very Soft Less Than Very Loose Soft 0.25 to Loose Firm 0.5 to Medium Stiff 1.00 to Dense Very Stiff 2.00 to 4.00 Over 50 Very Dense Hard greater than 4.00 (1) DESCRIPTIVE TERMS FOR SOIL DESCRIPTION CRITERIA MOISTURE Stratified Laminated Fissured Slickensided Blocky Lensed Alternating layers of varying material or color with layers at least 6 mm thick. Alternating layers of varying material or color with the layers less than 6 mm thick. Breaks along definite planes of fracture with little resistance to fracturing. Fracture planes appear polished or glossy, sometimes striated. Cohesive soil that can be broken down into small angular lumps which resist further breakdown. Inclusions of small pockets of different soils. Dry Moist Very Moist Wet Parting Seam Layer Trace Few Little With No water evident in sample; fines less than plastic limit. Sample feels damp; fines near the plastic limit Water visible on sample; fines greater plastic limit and less than liquid limit Sample bears free water; fines greater than liquid limit. INCLUSIONS Inclusion <1/8" thick extending through sample Inclusion 1/8" to 3" thick extending through sample. Inclusion >3" thick extending through sample. <5% of sample. 5% to 10% of sample. 15 to 25% of sample. 15% to 29% of sample. (1) Fugro Consultants, Inc. NOTE: Information on each boring log is a compilation of subsurface conditions and soil and rock classifications obtained from the field as well as from laboratory testing of samples. Strata have been interpreted from commonly accepted procedures. The stratum lines on the logs may be transitional and approximate in nature. Water level measurements refer only to those observed at the times and places indicated, and may vary with time, geologic condition or construction activity. REFERENCES: 1) ASTM D ) Peck, Hanson and Thornburn, (1974), Foundation Engineering. PLATE 8

25 TERMS AND SYMBOLS USED ON BORING LOGS FOR ROCK ROCK TYPES SAMPLER TYPES LIMESTONE SHALE SANDSTONE Thinwalled Tube Rock Core WEATHERED LIMESTONE WEATHERED SHALE WEATHERED SANDSTONE Standard Penetration Test Auger Sample WEATHERED DOLOMITE DOLOMITE GRANITE THD Cone Penetration Test Bag Sample SOLUTION & VOID CONDITIONS WEATHERING GRADES OF ROCKMASS (1) Void Cavities Vuggy Vesicular Porous Cavernous Interstice; a general term for pore space or other openings in rock. Small solutional concavities. Containing small cavities, usually lined with a mineral of different composition from that of the surrounding rock. Containing numerous small, unlined cavities, formed by expansion of gas bubbles or steam during solidification of the rock. Containing pore, interstices, or other openings which may or may not interconnect. Containing cavities or caverns, sometimes quite large. Most frequent in limestones and dolomites. Slightly Moderately Highly Completely Residual Soil Discoloration indicates weathering of rock material and discontinuity surfaces. Less than half of the rock material is decomposed or disintegrated to a soil. More than half of the rock material is decomposed or disintegrated to a soil. All rock material is decomposed and/or disintegrated to soil.the original mass structure is still largely intact. All rock material is converted to soil.the mass structure and material fabric are destroyed. HARDNESS BEDDING THICKNESS (2) Friable Low Hardness Moderately Hard Very Hard Crumbles under hand pressure Can be carved with a knife Can be scratched easily with a knife Cannot be scratched with a knife Very Thick Thick Thin Very Thin Laminated Thinly-Laminated >4' 2'-4' 2"-2' 1/2"-2" 0.08"-1/2" <0.08" JOINT DESCRIPTION SPACING INCLINATION Very Close <2" Horizontal 0-5 Close 2"-12" Shallow 5-35 Medium Close 12"-3' Moderate Wide >3' Steep Vertical SURFACES Slickensided Polished, grooved Smooth Planar Irregular Undulating or granular Rough Jagged or pitted Fugro Consultants, Inc. NOTE: Information on each boring log is a compilation of subsurface conditions and soil and rock classificaitons obtained from the field as well as from laboratory testing of samples. Strata have been interpreted by commonly accepted procedures. The stratum lines on the logs may be transitional and approximate in nature. Water level measurements refer only to those observed at the times and places indicated, and may vary with time, geologic condition or construction activity. REFERENCES: 1) British Standard(1981) Code of Practice for Site Investigation BS ) The Bridge Division, Texas Highway Dept. Foundation Exploration & Design Manual, 2nd Edition,revised June,1974. PLATE 9

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