Reduced Size_ Geotech Donna Pump to Brownsville SandB.pdf

FINAL

TECHNICAL MEMORANDUM

FOR

Geotechnical Explorations of Levee System Within the Lower Rio Grande Flood Control Project

DONNA PUMP TO BROWNSVILLE LEVEE

Prepared for:

United States Section, International Boundary & Water Commission

Submitted / Prepared by:

Project Manager: Daniel O. Rios, PE Deputy Project Manager: Sharlotte L. Teague, PE

In Association With:

TSI Laboratories, Inc.

Contract No. IBM05D0001 Task Order No. IBM06T0010

September 28, 2007

Contract No. IBM05D0001 Order No. IBM06T0010 i

ACKNOWLEDGEMENTS

The preparation of this document included the collaborative participation of the following parties:

US Section, International Boundary & Water Commission n

• Colleen Jaye Elliott Contracting Officer El Paso

• Isela Canava Technical Advisor El Paso

• Rick Reyes, PE Project Manager Mercedes

Consultant Team n

• Daniel O. Rios, PE Project Manager S&B, McAllen

• Sharlotte L. Teague, PE Deputy Project Manager S&B, McAllen

• Diana L. Izaguirre Engineering Assistant S&B, McAllen

• George Barrera Inspector S&B, McAllen

• Jesse P. Rodriguez, PE Geotechnical Engineer TSI, Victoria

All geotechnical testing, evaluations and analysis for this document were prepared, and released for interim review under the authority of

Jesse P. Rodriguez, PE Texas No. 57352 Date: 9-28-2007

This document is not to be used for bidding, construction, or permit purposes.

TABLE OF CONTENTS

Page

Section I

Section II

Section III

Section IV

Section V

PURPOSE OF TECHNICAL MEMORANDUM

I.1 Introduction / Background ……………………….……… 1

I.2 Project Description ………………..………………………. 2

I.3 Scope of Work ………………..………………………. 2

I.4 Records / References / Acronyms………………………… 3

SAMPLING AND TESTING

II.1 Field Exploration and Sampling………………………….. 4

II.2 Testing ………………..……………………………….. 4

SITE CONDITIONS

III.1 Levee Characteristics / Area Geology.………………….. 4

III.2 Subsurface………………..……………………………….. 5

III.3 Groundwater………..……………………………….. 5

EVALUATION

IV.1 General..………………………………………………….. 6

IV.2 Potential Vertical Rise…..……………………………….. 6

RECOMMENDATIONS

V.1 Site Preparation………………………………………….. 6

V.2 Selection and Placement of Fill ……………………….. 7

V.3 Settlement Analysis …………………………………….. 7

V.4 Slope Stability – General ……………………………….. 7

V.5 Construction Services…………………………………….. 8

V.6 Limitations………………..……………………………….. 8 ii

TABLE OF CONTENTS

Appendix A

Appendix B

Appendix C

Appendix D

Appendix E

Appendix F

Appendix G

Appendix H

Appendix I

TESTING PROCEDURES / USE OF REPORT

SELECT FILL REQUIREMENTS

SUMMARY OF SOIL PROPERTIES

BORE LOGS

UNCONFINED COMPRESSION

CONSOLIDATION

TRIAXIAL (UU)

POTENTIAL VERTICAL RISE

BORE COORDINATES

iii

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Section I Purpose of Study

I.1 Introduction / Background The United States Section of the International Boundary and Water Commission (USIBWC) recently conducted hydraulic and aerial geophysical studies to assess the ability of the United States levees of the Lower Rio Grande Flood Control Project (LRGFCP) to safely contain flood flows in the Rio Grande. From these studies, the USIBWC has determined that certain reaches of the levees require rehabilitation improvements for safe containment of the LRGFCP design flood flows.

The LRGFCP extends from the town of Peñitas, Texas at its upstream end, to 28 miles above the Gulf of Mexico, a distance of about 158 river miles. The LRGFCP has two diversion dams, Anzalduas Dam and Retamal Dam, approximately 17 and 57 river miles below Peñitas, which divert portions of the flood flows into the Main Floodway and the Mexico Floodway, respectively. The LRGFCP was constructed to provide flood protection to urban, suburban, and irrigated lands in the Rio Grande delta in both the United States and Mexico. Each country designed and constructed the portion of the LRGFCP located in its territory.

The USIBWC has developed a workplan to raise levees within the LRGFCP anywhere from 1 to 8 feet in height. That work plan is available at www.ibwc.state.gov. The geotechnical investigations are for the purpose of determining foundation stability for the added loading as well as to evaluate potential for seepage or piping through or below the levee in critical and questionable areas, in preparation for design of the levee rehabilitation projects. These areas have been identified in the US Army Corps of Engineers (USACE) Engineering Research Development Center (ERDC) reports “Assessment of U.S.

International Boundary and Water Commission, LRGV Levees, South Texas” dated October 2003 and “Supplement to Condition Assessment of U.S. International Boundary and Water Commission, LRGV Levees” dated June 2004.

On September 28, 2006 a task order was issued by the USIBWC to S&B Infrastructure, Ltd. (S&B), as Contractor, to prepare a technical memorandum for geotechnical explorations of the existing levee system within the LRGFCP. S&B subcontracted the geotechnical exploration, laboratory testing, and evaluations to TSI Laboratories, Inc. (TSI) out of Victoria, Texas. The following information, along with a Borehole Location Map under separate cover, comprises the Technical Memorandum – Geotechnical Explorations of Levee System within the Lower Rio Grande Flood Control Project for the Donna Pump to Brownsville Levee.

I.2 Project Description: Donna Pump to Brownsville Levee The Donna Pump to Brownsville Levee is approximately 67 miles in length (from the Carlson Settling Basin to the Retamal diversion Dam) beginning from 4650 feet west of FM 493 south of Donna near the Las Palomas State Wildlife Park to Brownsville. Encroachment and overtopping information from the 2003 USIBWC hydraulic model for the LRGFCP identify this levee reach as needing to be raised approximately 1 to 3 feet.

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I.3 Scope of Work The work to be performed included geotechnical investigations and evaluations along the alignment of the levee reach. Field work was coordinated with the USIBWC Mercedes Field Office and with the US Fish and Wildlife Service (USFWS). The technical memorandum contains the findings of the geotechnical investigations and evaluations, and also includes a set of location maps (24 inch x 36 inch, scale1 inch = 1,000 feet) under separate cover.

Specific activities and requirements that were performed by the Contractor included the following:

(a) Geotechnical Borings.

The field drilling services for the levee reach included drilling borings at an average spacing of approximately 500 linear feet, altering the spacing where required to drill if anomalies were discovered during the geophysical study. For the Donna Pump to Brownsville Levee, this equated to drilling a total of 193 borings along the top of the existing levee. These borings were drilled to depths of approximately 5 feet below the average ground surface elevation of the terrain on both sides of the levee, ranging from 11 to 20 feet below existing top-of-levee grades. If auger refusal was encountered in these borings prior to achieving their intended depths, the borings were terminated 5 feet into rock. All boring locations were accessible to a truck mounted drilling rig.

(b) General Procedures.

In all test borings, ground water level readings were taken upon completion of drilling activities, and the borings were backfilled utilizing auger cuttings generated during drilling operations. Activities did not include, and were not required for, the installation of monitor wells to assess ground water conditions.

All borings were located in the field utilizing tape and right angle measurements from existing benchmarks. Final boring locations were surveyed in the field following completion of the drilling activities.

Standard geotechnical drilling techniques were utilized for all borings. No environmentally sensitive boring sites were included in this scope. Soil cuttings were placed back in the test holes following completion of drilling activities, and therefore containerizing or disposal of the soil cuttings were not be required.

All drilling activities were logged by TSI. Samples were taken using conventional split-spoon and/or Shelby-tube sampling techniques. If auger refusal was encountered, air-rotary and/or mud-rotary drilling techniques were utilized to advance the borings to their final depths, and grab samples were collected from the cuttings. Representative portions of all samples were sealed and packaged for transportation to TSI laboratories.

(c) Laboratory Study.

Upon completion of the subsurface exploration, TSI conducted the following tests to define the strength and classification characteristics of the subsurface soils: moisture content, Atterberg

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Limits (plasticity), gradation, unconfined compression, consolidation, and unconsolidated-undrained (UU) triaxial tests.

I.4 References and Definition of Acronyms The following records and information were reviewed and provided for background:

(a) IBWC Minute No. 238, September 10, 1970, “Improvement of the International Flood Control Works of the Lower Rio Grande”

(b) USIBWC 2003 Hydraulic Study for LRGFCP

(c) USACE ERDC Levee Assessment Data:

(1) LIDAR Point Data

(2) LRGFCP Condition Assessment Plates

(3) “Assessment of U.S. International Boundary and Water Commission, LRGV Levees, South Texas”, dated October 2003

(4) “Supplement to Condition Assessment of U.S. International Boundary and Water

Commission, LRGV Levees”, dated June 2004

Although some acronyms have been defined above, Table I-1 on the below provides a consolidated summary of terms used throughout this report.

Acronym Definition

ERDC Engineering Research Development Center (H:V) Slope, horizontal to vertical LRGFCP Lower Rio Grande Flood Control Project psf pounds per square foot PVR Potential Vertical Rise UU unconsolidated-undrained USACE US Army Corps of Engineers USFWS US Fish and Wildlife Service USIBWC United States Section, International Boundary and Water Commission

Table I-1: Definition of Terms

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Section II Sampling and Testing

II.1 Field Exploration and Sampling Geotechnical exploration of the Donna Pump to Brownsville Levee included 193 soil test borings to depths ranging from 11 to 20 feet below existing top-of-levee grades. Boring locations were determined in the field with preliminary location maps provided by S&B and reviewed by the USIBWC. Boreholes were advanced using solid stem augers, and samples of the materials encountered were obtained by split barrel sampling in conjunction with standard penetration testing.

Final elevations and coordinates of each borehole were obtained through field survey, and are located in Appendix I. Bore logs are documented in Appendix D, as well as the Borehole Location Map.

II.2 Testing Appendix A identifies and summarizes testing procedures used for this technical memorandum;

Appendices C, E, F, G, and H include the testing results for soil properties, unconfined compression, consolidation, unconsolidated-undrained (UU) triaxial tests, as well as potential vertical rise, respectively.

Soil samples were examined and visually classified by the samples representative of the various soil strata encountered. TSI supplemented the field investigation with a laboratory testing program for determining additional engineering characteristics of the subsurface soils encountered. The laboratory testing program included visual classification of the soil/rock samples retrieved in general compliance with ASTM D-2488. Selected samples were also tested to determine the natural moisture contents and the Atterberg limits in overall compliance with ASTM D-2216 and D-4318, respectively.

The estimated shear strength values were obtained, in the field, by the use of a calibrated hand penetrometer. The shear strength of the selected cohesive soils were evaluated from unconfined compressive shear strength tests on undisturbed sample in general conformance with ASTM D-2166.

Other laboratory tests included consolidation tests and triaxial tests all following the testing standards found in ASTM D-2435 and D-4767, respectively.

The laboratory testing program was conducted in general accordance with applicable ASTM specifications. The samples not altered by laboratory testing, are to be retained for 30 days from the date of the test results and then be discarded. The test results are provided in various appendices attached to this technical memorandum as previously mentioned.

Section III Site Conditions

III.1 Levee Characteristics / Area Geology During field exploration, the following general observations were reported:

(a) The levees, in general, were in a stable and non-eroded condition;

(b) The top of the levees were found to be used as a gravel roadway;

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(c) The levee slopes and adjacent ground cover consisted of grass, native vegetation, small undergrowth, and small bushes;

(d) The existing levee slopes appeared stable with minimal erosion, with a 3:1 (H:V) side slope for most areas.

The “Geologic Atlas of Texas”, McAllen-Brownsville Sheet, indicates the areas in this reach range from Alluvium Deposits, to Windblown Deposits and Beaumont Formation (Pleistocene) of the Quaternary Period, with mostly clay, silt, sand and gravel; including mainly stream channel, point bar, natural levee, and backswamp deposits; concretions and massive accumulations of calcium carbonate (caliche) and concretions of iron oxide and iron-manganese oxides in zone of weathering. Also, areas of floodplain deposits consisting of mud veneer over meander belt sand, little grain preserved and grass covered.

III.2 Subsurface The site soils were evaluated by performing various field and laboratory tests on samples recovered during the drilling operations. The types of tests conducted on the subsurface samples are included in the Appendix of this technical memorandum. The soil strata and soil property results of the tests are summarized in Appendix C, and documented on the Bore Logs in Appendix D.

A key to bore log symbols and soil classifications, which defines the terms and descriptive symbols used on each boring log, is also presented in the Appendix D. The above descriptions are generalized to highlight stratification and engineering properties of the soils underlying this site. The bore logs should be consulted for specific information at each boring location.

Variations from the conditions indicated on the Bore Logs could occur between or beyond the boring locations. Also, the stratifications lines indicated on the Bore Logs represent approximate boundaries between soil and rock types and have been estimated based on an examination of the samples and on information from the drillers’ field logs. Actual transitions may vary somewhat from the approximate levels shown and could be gradual.

III.3 Groundwater In relatively pervious soils, like sands, the reported saturated soil condition is considered to be a relatively reliable indicator of groundwater table levels. However, in relatively impervious soils, water levels observed in the test borings, even after several days, may not provide reliable indications of groundwater table elevations; therefore, water levels at later times could be different from those observed during the subsurface exploration. It is noted that groundwater levels will fluctuate with seasonal climatic variations; however, groundwater is not a factor affecting levee design or construction at this site.

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Section IV Evaluation

IV.1 General The stiff to firm to hard clay soil mixtures underlying this site are strong, moderate to highly expansive soils that are competent to support the proposed levee system rehabilitation improvements.

A surcharge load (due to heavy construction machinery) at the top of the levee is assumed to be in the range of 250 pounds per square foot (psf). TSI understands that the existing flood control levee system will consist of raising the top of levee elevation from approximately 1 to 3 feet in height, with side slopes at about 3:1 (H:V) and matching the existing levee slopes. Based on this information, the ultimate levee shape would be trapezoidal (16 feet wide on top, and approximately 64 feet wide on the bottom. Recommendations for site preparation, levee design, and construction are presented in the following section.

IV.2 Potential Vertical Rise Potential vertical soil movements have been estimated using the Texas Department of Transportation method TEX-124-E, Potential Vertical Rise (PVR). This method utilizes the soils in-situ moisture conditions and plasticity characteristics within the active zone. It is estimated that depth of the active zone at this site is approximately 15 feet below natural grades. The estimated PVR values are identified in Appendix H. A sustained surcharge load of 1 pound per square inch is assumed to be supplied as a sustained live load in the PVR calculations. It is noted that the PVR estimates are provided as an indicator of the severity of potential soil movements at this site and are not intended as a prediction of actual soil foundation movements.

Section V Recommendations All recommendations are based on knowledge of the area; however, the project design team should specify actual construction requirements. As presented at the beginning of this technical memorandum, based on information provided, it is understood that the embankments will be raised a maximum of approximately 3 feet in height and that the side slope will be constructed to match the existing slopes which appear to be 3:1 (H:V), unless a steeper slope is required due to other requirements and/or limitations. If required due to height increase and slope requirements, the USIBWC levee footprint will be expanded. These levee slope conditions will keep the levee in a general trapezoidal shape. During flood conditions it is anticipated that there will be a minimum of 3 feet of freeboard after the levee rehabilitation is completed.

V.1 Site Preparation Site preparation should consist, initially, of clearing and the stripping of vegetation, loose soil materials, and any materials containing significant organic material from any site areas to be improved. More than ten percent by volume is considered organic material.

After levee site preparation, the exposed subgrade should be proof rolled with appropriate construction equipment weighing at least 15 tons. The purpose of this recommendation is to check the supporting soils for weak or soft areas prior to fill placement and compaction. The exposed subgrade should then be moisture conditioned between two (2%) percentage points below and four (4%) percentage points

-7 above the optimum moisture content and be compacted to at least ninety-five (95%) percent of the maximum dry density determined per ASTM D698. This operation should be observed and evaluated by qualified geotechnical personnel experienced in earthwork operations.

If weak or soft areas are evidenced during proof rolling operations, the soil in the subject area should be removed to expose competent subgrade soils in both horizontal and vertical limits. The excavated soils, provided they are not contaminated with deleterious materials, or clean imported fill soils can be used to restore grade at these isolated areas; any imported fill should meet the requirements for select embankment fill. The fill requirements and compaction should be in accordance with recommendations found in Appendix B.

V.2 Selection and Placement of Fill Fill materials, where needed or desired, should be low to moderate plasticity sandy clay soil mixtures or imported clayey sand, or mixtures of clay/sand/ and gravel. Recommended fill specifications are included in Appendix B and these may be used as a guide for the placement of fill and for pavement construction. All select fill materials should have a plasticity index ranging from twelve to eighteen percent (12% ~ 18%).

Particular attention should be given to maintaining the proper moisture content during compaction and to preventing the fill from drying before subsequent lifts are placed. Levee subgrade preparation should include rough grading prior to fill placement for proper drainage control and establishing final finish grade elevations.

V.3 Settlement Analysis The deep penetration of vertical pressure (due to the levee heights above natural grade) could cause excessive consolidation of soft soil layers at a considerable depth below the foundation even though a relatively low unit surcharge load is used. Settlement of saturated cohesive soils is the summation of

(a) immediate settlement, (b) consolidation settlement, and (c) secondary compression. Thus, as loads are applied, the immediate settlement occurs, when excess pore pressures generated by the loads are dissipated you have consolidation settlement, and secondary compression is basically controlled by the composition and structure of the soil skeleton and is usually small compared to the consolidation settlement.

Settlement analyses have been performed on the basis of the e-log p curves in conjunction with the consolidation test results to determine the theoretical primary consolidation settlement of the proposed mat foundations. It is determined that long term settlement is very limited due to the maintenance equipment live loads of 250 psf.

V.4 Slope Stability - General The term ‘slope stability’ as previously stated in the USACE ERDC report defined the term as “the ability of a levee to maintain its integrity with few signs of distress …” This is quite evident in TSI’s experience in investigating distressed states of slope failure for different projects. Basically, the failure of a mass of soil on a failed slope is termed a slide and is caused by the downward and lateral movement of the entire mass of soil that has been compromised and has lead to the failure. There

-8 exists many modes of conceivable failures or slides, many times it is a slow process and many times it occurs suddenly; and which may occur with or without any apparent incitement or provocation.

Typically, the excavation or soil removal of the toe or foot of the existing slope causes slides;

however, for many instances it is the gradual disintegration of the soil structure itself. It usually begins with the hairline cracks that further subdivide the soil structure into larger angular fragments, while in others it is a direct cause by the increase in pore-water pressure, or in other instances it is related to an external shock force that liquefies the soil.

There exists a large variety of conditions for slope stability that often times it defies the theoretical analysis performed; therefore, the stability computations based on test results can only be relied upon when all conditions of the slope stability computations are satisfied. There are always undetected anomalies in the soil, such as old remnants of sliding, hairline cracks, or thin water-bearing seams of sand, which will disqualify the slope stability computation results..

V.5 Construction Services It is recommended that a professional geotechnical laboratory be retained to provide soil-testing services during grading and levee rehabilitation construction activities. Services would include observations for compliance with the plans, specifications, and geotechnical recommendations and to incorporate design changes if the subsurface conditions differ from those anticipated before construction.

V.6 Limitations The evaluation and recommendations submitted in this report are based, in part, upon the information obtained from the 193 soil borings drilled for this levee reach. The nature and extent of variations in the soil conditions between or beyond the borings and excavations may not become evident until actual construction.

The transition lines shown on the boring logs are approximate and the actual transitions may be gradual. If changes in nature or design of the project are planned, the conclusions and recommendations in this report should be reviewed by a soils engineer and, if necessary, modified.

Soil samples not altered by laboratory testing will be retained for a period of 30 days and then, unless otherwise directed, will be discarded.

This report has been prepared for the exclusive use of the USIBWC and their design team for specific application to the Donna Pump to Brownsville Levee for the LRGFCP in Hidalgo County, Texas according to accepted foundation-engineering practices. No other warranty, expressed or implied, is made. Additional information regarding the uses and limitations of geotechnical engineering reports is included in the Appendix A.

LATERAL A – DONNA PUMP – RETAMAL DAM LEVEE

APPENDIX A

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Field and Laboratory Testing and Use of Geotechnical Reports

Field and Laboratory Testing Procedures and Use of Geotechnical Reports

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I. Field Testing

A. Boring Procedure Between Samples The borehole is extended downward, between samples, by continuous flight, hollow or solid stem augers or by rotary drilling techniques using bentonite drilling fluid or water.

B. Penetration Test and Split-Barrel Sampling of Soils (ASTM D-1586) This sampling method consists of driving a 2-inch outside diameter split barrel sample using a 140 pound hammer freely falling through a distance of 30 inches. The sampler is first seated 6 inches into the material to be sampled and then driven an additional 12 inches. The number of blows required to drive the sampler the final 12 inches is knows as the Standard Penetration Resistance.

Recovered samples are first classified as to color and texture by the driller. Later, in the laboratory, the driller’s field classification is reviewed by the soils engineer who examines each sample.

C. Thin-walled Tube Geotechnical Sampling of Soils (ASTM D-1587) This method consists of pushing thin walled steel tubes, usually 3 inches in diameter, into the soils to be sampled using hydraulic or other means. Cohesive soils are usually to be sampled in this manner and relatively undisturbed samples are recovered.

D. Soil Investigation and Sampling by Auger Borings (ASTM D-1452) This method consists of augering a hole and removing representative soil samples from the auger flight or bit at 5 foot intervals or with each change in the substrata. Disturbed samples are obtained and this method is, therefore, limited to situations where it is satisfactory to determine the approximate subsurface profile.

E. Diamond Core Drilling for Site Investigation (ASTM D-2113) This method consists of advancing a hole into hard strata by rotating a single or double tube core barrel equipped with a cutting bit. Diamond, tungsten carbide, or other cutting agents may be used for the bit. Wash water is used to remove the cuttings and to cool the bit. Normally, a 2 inch outside diameter by 1-3/8 inch inside diameter (NX) coring bit is used unless otherwise noted.

The rock or hard material recovered within the core barrel is examined in the field and in the laboratory and the cores are stored in partitioned boxes. The core recovery is the length of the material recovered and is expressed as a percentage of the total distance penetrated.

F. Visual – Manual Soil Classification Procedure (ASTM D-2488) This procedure is a visual – manual soil classification methodology for the description of soil for engineering purposes when precise soil classification is not required.

II. Laboratory Testing

A. Particle Size Analysis of Soils (ASTM D-422 and TEX 110-E) Atterberg Limits determine the soil’s plasticity characteristics. The soil’s Plasticity Index (PI) is representative of this characteristic and is the difference between the Liquid Limit (LL) and the

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Plastic Limit (PL). The LL is the moisture content at which the soil will flow as a heavy viscous fluid. The PL is the moisture content at which the soil begins to lose its plasticity. The test results are presented on the boring logs adjacent to the appropriate sampling information.

B. Particle Size Analysis of Soils (ASTM D-422 and TEX 110-E) Grain size analysis tests are performed to determine the particle size and distribution of the samples tested. The grain size distribution of the soils coarser than the Standard Number 200 sieve was determined by passing the sample through a standard set of nested sieves.

C. Laboratory Determination of Water (Moisture) Content of Soil and Rock (ASTM D-2216 and TEX 103-E) The moisture content of soil is defined as the ratio, expressed as a percentage, of the weight of water in a given soil mass to the weight of solid particles. It is determined by measuring the wet and oven dry weights of a soil sample. The test results are presented on the boring logs.

D. Unconfined Compressive Strength and Cohesive Soil (ASTM D-2166) The unconfined compressive strength of soil is determined by placing a section of an undisturbed sample into a loading frame and applying an axial load until the sample fails in shear. The test results are presented on the boring logs adjacent to the appropriate sampling information.

E. California Bearing Ratio (CBR) of Lab Compacted Soils (ASTM D-1883) The CBR test is performed by compacting soil in a six inch diameter mold at the desired density, soaking the sample for four days under a surcharge load approximating the pavement weight and then testing the soils in punching shear. A two inch diameter piston is forced into the soil to determine the resistance to penetration. The CBR is the ratio if the actual load required to produce

0.1 inches of penetration to that producing the same penetration in a standard crushed stone.

F. Swell Test (ASTM D-4546) The swell test is performed by confining a one inch thick specimen in a 2-1/2 inch diameter stainless steel ring and loading the specimen to the approximate overburden pressure. The test specimen is then inundated with distilled water and allowed to swell for forty-eight hours. The volumetric swell is measured as a percentage of the total volume and is converted mathematically to linear swell.

G. Compaction (ASTM D-698, D-1557, TEX 113-E or 114-E) The compaction test is performed by compacting soil in a steel mold at varying moisture contents.

Layers are compacted using a hammer weight and number of blows per layer which vary with the different test procedures, ASTM D-698, D-1557, TEX 113-E and 114-E. The data is plotted and the maximum unit weight and optimum moisture content determined. The test results are given in the appendix with a notation of the test method used.

H. Classification of Soils for Engineering Purposes (Unified Soil Classification System, D-

2487) This standard describes a system for classifying mineral and organo-mineral soils for engineering purposes based on Laboratory determination of particle-size characteristics, LL, and PI and shall be used when precise classification is required.

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III. Use of Geotechnical Reports The following observations and suggestions are provided to assist in the utilization of this geotechnical engineering report and to reduce construction problems and delays related to the soil and groundwater conditions.

A. Report Is Based Upon Specific Site And Project A geotechnical report is based on a subsurface exploration conducted on a specific site and planned using specific project information. The project information typically includes structure size and configuration, type of construction, and general location on the site. Limitations, such as existing buildings or utilities, specific foundation requirements for the structures, budget limitations, and the level of risk assumed by the client may affect the scope of the exploration.

Since the report applies to a specific structure and site, the geotechnical report should not be used in the following circumstances unless the geotechnical engineer has reviewed the changes and concurs in the use of the report:

• When the nature of the proposed structure changes;

• When the size, configuration, or elevation is changed;

• When the location of the structure on the site is changed; and,

• When there is a change of ownership

B. Findings Are Professional Estimates The actual subsurface conditions are determined only at the boring locations and only at the time the samples are taken. The information is extrapolated by the geotechnical engineer who then renders professional opinions regarding the characteristics of the subsurface materials, the behavior of the soils during construction, and appropriate foundation designs. No exploration, however complete, can be assured of sampling the entire range of soil conditions. The soils may vary between or beyond the borings and stratum transitions may be more gradual or more abrupt, and all types of oils and rock existing on the site may not be found in the borings. The geotechnical engineer is often retained during construction to evaluate variances and recommend solutions to problems encountered on the site.

C. Subsurface Conditions Can Change Grading operations on or close to the site, floods, groundwater fluctuations, utility construction, and utility leaks are among the events which can change the subsurface conditions. The geotechnical engineer should be kept appraised of such events.

D. Geotechnical Services Are Performed For Specific Purposes And Persons A geotechnical report may have been made to evaluate foundation alternatives only, for preliminary site evaluation, or for other limited purposes. The exploration may also have been limited by the direction of the client, budget limitations, or the level of risk assumed by the client.

Therefore, no one other than the original client should use the report for its intended purpose or other purposes without conferring with the geotechnical engineer.

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E. Geotechnical Reports Are Subject To Misinterpretation Geotechnical reports are based on the project information available at the time the report was made and the judgment and opinions of the geotechnical engineer. This specialized information is subject to misinterpretation by other design professionals, contractors and owners. The geotechnical engineer should be retained during the design process to interpret the recommendations and review the adequacy of the plans and specifications relative to geotechnical issues. The boring logs should not be separated from the geotechnical report but, rather, the entire report should be made available to the contractors and others needing this information.

APPENDIX B

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Select Fill Requirements

Recommendations for Placement of Select Fill

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I. General The soils engineer should be the owner’s representative to control the placement of compacted fill.

The soils engineer should approve the subgrade preparation, the fill materials, the method of placement and compaction, and provide written approval of the complete fill.

II. Preparation of Existing Ground All topsoil, plants and other organic material shall be removed. The exposed surface shall be scarified, moistened if necessary, and compacted in the manner specified for subsequent layers of fill.

III. Select Fill Material Fill shall have a Liquid Limit (LL) of 37 or less and a Plasticity Index (PI) ranging from twelve to eighteen percent (12% ~ 18%). The fill shall contain no organic or other perishable material, and no stones larger than six (6) inches. Fill material should be approved by the soils engineer.

IV. Placing Select Fill Fill materials shall be placed in horizontal layers not exceeding eight (8) inches thickness after compaction. Successive loads of material shall be dumped so as to secure even distribution, avoiding the formation of layers of lenses of dissimilar materials. The contractor shall route his hauling equipment to distribute travel evenly over the fill area.

V. Compaction of Select Fill

A. Moisture Control: The moisture content of the fill material shall be distributed uniformly throughout each layer of the material. The allowable range of moisture content during compaction shall be within plus two (+2) and minus two (-2) percentage points of the optimum moisture content. The contractor may be directed to add necessary moisture to the material either in the borrow area or upon the fill surface or to dry the material, as directed by the soils engineer. The drying of cohesive soils between lifts to moisture contents less than seventy percent (70%) of optimum before the placement of subsequent lifts shall be avoided or the fill reworked at the proper moisture content.

B. Compaction: The material in each layer shall be compacted to obtain proper densities.

Compaction by the hauling equipment alone will not be considered sufficient. Structural fills, including subgrade, subbase and base, shall be compacted to densities equivalent to the percentages of the Standard Proctor (ASTM D-698) or the Modified Proctor (ASTM D-1557) maximum dry density listed in Table B-1 on the next page. The Texas Department of Highways and Public Transportation Method TEX 113-E or TEX 114-E compaction test, which varies the compactive effort with soil type, may be substituted for the Standard or Modified Proctor methods and the percentages listed in Table B-1 used.

Soils classified as coarse grained soils are those with more than fifty (50) percent, by weight, retained on the No. 200 Standard Sieve.

Recommendations for Placement of Select Fill

B -2

PERCENT COMPACTION

AREA

Fine-Grained Soils ASTM D-698 (Standard)

Or

TEX 114-E

Coarse-Grained Soils ASTM D-1557 (Modified)

Or

TEX 114-E

Within five (5) feet of building lines, under footings, floors slabs, slab-on-grade foundations and structures attached to the buildings (i.e. walls, patios, steps).

95% 95%+

More than five (5) feet beyond building lines, under walks, and fill areas to be landscaped.

90% 90%

Levee structure, pavement subgrade and subbase, including lime-treated soils.

95% 95%+

Flexible Base

N/A 98%

Table B-1

VI. Comparison Testing Field density tests for the determination of the compaction of the fill should be performed by the geotechnical engineer in accordance with recognized procedures for making such tests. A representative number of tests shall be made in each compacted lift at locations selected by the soils engineer or his representative. For general structural and paving fills, one test per 3,000 square feet per lift with a minimum of three tests per lift is suggested.

APPENDIX C

C -0

Soil Properties Summary

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

B1 3 CL-ML 12 22 16 6 -0.67 75

B1 7 CL 18 38 24 14 -0.43 2.60 102 96

B1 10 CL 19 47 24 23 -0.22 0.21 0.04 0.76 98

B2 0 - 6 CL 0

B2 7 CL-ML 10 28 23 5 -2.60

B2 9 CL 14 0 104

B3 3 CL 12 36 23 13 -0.85 98

B3 7 CL 26 0 98

B3 9 CL 20 0 97

B3 11 CL 17 36 20 16 -0.19 0.21 0.04 0.76 107

B4 3 CH 14 56 23 33 -0.27 99

B4 5 CL 5 28 20 8 -1.88 86

B4 11 - 13 ML 0

B5 0 - 8 CL 0

B5 9 ML 9 29 27 2 -9.00 99

B6 1 CL 14 45 24 21 -0.48 91

B6 5 CL 11 40 17 23 -0.26 99

B6 6 - 11 SC 0

B7 5 CL 15 48 16 32 -0.03 95

B7 11 CH 21 61 22 39 -0.03 100

B8 5 CL 12 40 19 21 -0.33 55

B8 7 CL 22 0 0.66 102

B8 9 CL 18 47 21 26 -0.12 95

B9 7 CL 13 44 18 26 -0.19 99

B10 5 CL 10 0 81

B10 7 CL 19 0 0.61 105

B10 9 CL 18 40 20 20 -0.10 0.62 104 98

B10 11 CL 21 0 0.29 0.05 0.70 100

B11 3 CH 25 58 24 34 0.03 3.80 96 100

B11 9 CL 21 36 16 20 0.25 0.58 107 89

B12 3 CH 21 57 13 44 0.18 6.40 103 95

B12 7 CH 23 0 0.64 104

B12 9 CH 22 0 0.30 0.07 0.77 96

B12 12 CH 27 51 21 30 0.20 0.79 94 100

B13 7 CH 18 51 21 30 -0.10 0.73 98 100

B13 9 ML 6 23 22 1 -16.00 80

B14 5 CL 14 31 20 11 -0.55 91

B14 9 CL 18 29 13 16 0.31 98

B15 7 CL 15 36 13 23 0.09 98

B15 14 CL 26 47 22 25 0.16 0.77 95 96

B16 3 CL 13 32 23 9 -1.11 96

APPENDIX C

Soil Properties Summary

Bore Depth Description

C - 1

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B16 9 CL 9 33 17 16 -0.50 97

B17 5 CL 15 32 18 14 -0.21 99

B17 9 CH 24 67 25 42 -0.02 99

B17 13 CH 22 0 0.19 0.05 0.65 104

B18 5 CL 22 32 19 13 0.23 99

B18 9 CL 24 35 18 17 0.35 99

B18 15 CH 23 0 0.67 101

B19 3 CL 12 36 22 14 -0.71 96

B19 9 CL 27 40 22 18 0.28 100

B19 13 CL 27 0 0.77 95

B20 1 CL 17 41 20 21 -0.14 99

B20 7 CL 19 0 3.10 98 98

B20 16 CL 28 0 0.28 0.07 0.79 95

B21 0 - 4 CL 0

B21 5 CH 25 54 21 33 0.12 0.71 98 98

B21 9 CL 19 31 16 15 0.20 92

B21 12 CH 27 57 26 31 0.03 100

B21 16 CL 27 43 23 20 0.20 98

B22 0 - 4 CL 0

B22 5 CH 23 53 21 32 0.06 0.75 96 97

B22 7 CL 17 42 18 24 -0.04 98

B22 17 CH 30 58 22 36 0.22 0.83 92 100

B23 3 CL 15 49 21 28 -0.21 98

B23 9 CL 26 0 0.79 94

B23 13 CL 25 0 0.73 99

B23 16 CL 25 44 18 26 0.27 0.22 0.03 0.79 95 100

B24 7 CL 21 38 16 22 0.23 99

B24 9 CL 18 0 103

B24 16 SM 28 26 26 0 37

B25 5 CL 11 31 13 18 -0.11

B25 9 CL 15 33 16 17 -0.06 99

B25 14 - 16 SM 0

B26 3 CL 15 36 22 14 -0.50 98

B26 15 CL 33 30 18 12 1.25 97

B27 7 CL 15 29 15 14 0.00 95

B27 12 CL 25 32 21 11 0.36 100

B27 14 - 16 SM 0

B28 3 CL 16 35 18 17 -0.12 98

B28 9 CL 15 28 19 9 -0.44 89

B28 12 CL 18 0 0.10 0.02 0.61 106

B28 14 - 16 CH 29 52 21 31 0.26 0.81 93 90

B29 0 - 4 CL 0

B29 5 CH 27 61 38 23 -0.48 93 99

C - 2

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B29 7 CH 28 0 0.78 95

B29 9 CH 26 65 24 41 0.05 100

B29 11 CH 28 0 0.80 95

B30 1 CL 14 42 20 22 -0.27 98

B30 11 CH 30 60 24 36 0.17 0.83 92 100

B30 13 CH 29 0 0.26 0.06 0.86 92

B31 9 CL 25 44 20 24 0.21 0.75 96 99

B31 14 CL 32 39 18 21 0.67 99

B32 5 CL 19 35 17 18 0.11 91

B32 12 CL 26 0 0.83 92

B33 3 CL 17 32 16 16 0.06 97

B33 9 CL 20 33 20 13 0.00 97

B34 3 CL 21 44 19 25 0.08 2.80 97 95

B34 5 CL 25 0 0.75 96

B34 7 CL 22 35 19 16 0.19 96

B34 12 CL 26 44 20 24 0.25 0.72 98 99

B34 15 CL 27 0 0.24 0.04 0.78 96

B35 3 CL-ML 13 26 21 5 -1.60 96

B35 5 CH 28 59 23 36 0.14 0.86 91 100

B35 9 CL 26 34 24 10 0.20 0.86 91 98

B35 15 CL 31 38 21 17 0.59 99

B36 7 CL 20 28 16 12 0.33 94

B37 0 - 4 CL 0

B37 5 CH 16 71 33 38 -0.45 1.90 98 96

B37 9 CL 17 25 16 9 0.11 78

B37 15 CH 26 51 20 31 0.19 0.70 99 100

B38 1 CL 16 31 19 12 -0.25 98

B38 5 CL 23 0 0.66 101

B38 9 CL 23 0 0.67 102

B38 12 CL 23 39 21 18 0.11 98

B38 15 CL 26 0 0.19 3.04 0.75 98

B39 7 CL 27 0 0.92 88

B39 12 CL 22 41 16 25 0.24 96

B39 15 CL 28 30 22 8 0.75 99

B40 3 CL 16 35 19 16 -0.19 97

B40 7 CL 23 45 27 18 -0.22 0.65 97

B40 9 CL 23 0 102

B41 3 CL 14 35 18 17 -0.24 95

B41 9 CL 22 42 19 23 0.13 0.77 95 99

B41 14 CL 23 28 8 20 0.75 80

B41 17 CL 23 0 0.70 99

B42 5 CL 13 28 18 10 -0.50 86

B42 14 CL 22 35 16 19 0.32 97

C - 3

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B42 17 CH 24 58 23 35 0.03 100

B43 9 CL 13 33 16 17 -0.18 83

B44 1 CL 9 0 83

B44 5 CH 23 55 24 31 -0.03 99

B44 7 CH 22 54 24 30 -0.07 2.70 90

B44 9 CH 27 0 0.79 94

B44 14 CH 27 71 28 43 -0.02 0.22 0.04 0.83 93 100

B44 18 CH 28 0 0.89 90

B45 5 CL 16 45 19 26 -0.12 96

B45 7 CH 21 66 24 42 -0.07 0.71 99 100

B45 14 CH 28 0 0.82 93

B45 18 CH 29 69 32 37 -0.08 100

B46 3 CL 11 40 21 19 -0.53 96

B46 9 CL 11 0 87

B46 18 CH 30 62 22 40 0.20 0.83 92 100

B47 7 CL 11 34 19 15 -0.53 93

B47 14 CL 19 47 19 28 0.00 99

B47 18 CL 29 0 0.86 92

B48 3 CL 13 49 20 29 -0.24 95

B48 14 CL 14 43 21 22 -0.32 98

B48 18 CH 30 0 0.88 90

B49 7 CL 20 43 20 23 0.00 97

B49 9 CL 21 0 0.64 103

B49 14 CL 25 0 0.20 0.04 0.75 98

B49 19 CL 25 49 17 32 0.25 0.69 100 100

B50 5 CL 15 39 21 18 -0.33 98

B50 9 CH 22 55 22 33 0.00 0.64 103 99

B50 15 CH 21 56 21 35 0.00 0.73 97 100

B51 7 CL 18 37 16 21 0.10 99

B51 9 CL 17 45 19 26 -0.08 0.54 109 97

B52 3 CL 14 42 23 19 -0.47 99

B52 7 CL 18 46 18 28 0.00 0.66 101 94

B52 9 CL 21 0 0.25 0.05 0.67 102

B52 14 CL 18 0 0.60 105

B53 0 - 6 CL 0

B53 7 CH 20 51 22 29 -0.07 3.10 99 97

B53 9 CH 19 0 0.64 103

B53 16 CH 27 56 25 31 0.06 98

B54 0 - 6 CL 0

B54 7 CH 19 53 19 34 0.00 99

B54 9 CH 21 0 0.65 102

B54 14 CL 22 48 24 24 -0.08 97

B54 16 CL 25 0 0.72 98

C - 4

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B55 5 CL 19 48 20 28 -0.04 96

B55 7 CL 22 0 0.76 96

B55 9 CL-ML 16 24 17 7 -0.14 86

B55 16 CL 20 33 15 18 0.28 97

B56 3 CL 11 30 15 15 -0.27 92

B56 7 CH 22 50 19 31 0.10 0.77 96 100

B56 13 - 18 CL 0

B57 3 CL 11 34 17 17 -0.35 95

B57 7 CH 23 53 21 32 0.06 99

B57 9 CL 24 0 0.80 95

B57 14 CL 26 0 0.27 0.05 0.79 95

B57 16 CL 24 46 19 27 0.19 0.65 102 97

B58 7 CL 19 34 22 12 -0.25 97

B58 14 CL 26 0 0.75 96

B58 17 CL 28 34 16 18 0.67 99

B59 3 CL 17 40 20 20 -0.15 98

B59 13 CL 34 32 22 10 1.20 100

B60 5 CL 11 24 16 8 -0.63 86

B60 7 CL 26 49 19 30 0.23 0.78 95 100

B60 9 CL 27 35 22 13 0.38 99

B61 3 CL 16 34 18 16 -0.13 88

B62 5 CL 23 44 19 25 0.16 98

B62 7 CL 30 32 18 14 0.86 98

B62 9 CL 23 0 101

B62 14 CL 31 48 21 27 0.37 100

B63 0 - 2 CL 0

B63 3 CH 23 61 26 35 -0.09 2.80 95 100

B63 7 CL 27 0 0.21 0.03 0.82 94

B63 9 CL 25 31 20 11 0.45 0.76 99 86

B64 0 - 2 CL 0

B64 3 CL-ML 18 31 27 4 -2.25 93

B64 7 CL 27 35 17 18 0.56 89

B64 9 CL 24 0 96

B64 11 CL-ML 36 28 24 4 3.00 96

B65 1 CL 8 31 18 13 -0.77 83

B65 9 CL 18 43 19 24 -0.04 98

B66 0 - 4 CL 0

B66 5 CH 19 60 20 40 -0.03 100

B66 7 CH 23 0 0.64 103

B66 9 CH 23 0 0.15 0.03 0.67 102

B66 11 CL 23 44 18 26 0.19 0.63 103 100

B67 5 CL 15 33 18 15 -0.20 98

B67 9 CL 20 0 0.60 106

B67 12 CL 20 42 20 22 0.00 100

C - 5

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B68 0 - 6 CL 0

B68 7 CL-ML 10 29 22 7 -1.71 97

B68 9 CL 10 28 16 12 -0.50 98

B68 13 SM 17 20 20 0 44

B69 5 CL 16 47 17 30 -0.03 100

B69 14 CH 9 64 29 35 -0.57 100

B70 5 CL 19 41 19 22 0.00 100

B71 3 CL 20 48 20 28 0.00 100

B71 5 CL 23 42 17 25 0.24 98 98

B71 7 CL 25 41 21 20 0.20 98

B71 10 CL 24 32 20 12 0.33 0.29 0.03 0.85 92

B72 3 CL 16 36 21 15 -0.33 2.90 97 98

B72 7 CL 22 0 0.69 101

B72 9 CL 21 40 29 11 -0.73 100

B72 12 CL 20 0 0.62 104

B73 7 CL 23 44 19 25 0.16 0.74 97 99

B73 12 CL 20 0 0.75 96

B74 3 CL 17 46 26 20 -0.45 99

B74 7 CH 20 0 0.77 95

B74 9 CH 18 52 19 33 -0.03 2.90 98 100

B74 14 CH 27 0 0.73 97

B75 3 CH 15 54 18 36 -0.08 99

B75 7 CH 19 0 0.71 99

B75 9 CH 20 52 17 35 0.09 99

B75 14 CH 25 0 0.69 100

B76 5 CL 13 42 21 21 -0.38 98

B76 9 CL 15 49 19 30 -0.13 98

B76 17 CL 20 0 0.59 106

B77 0 - 8 CL 0

B77 9 CH 17 55 19 36 -0.06 98

B77 14 CH 23 0 0.70 99

B77 17 CL 21 49 20 29 0.03 0.65 102 97

B78 0 - 2 CL 0

B78 7 CH 20 59 20 39 0.00 99

B78 9 CH 21 0 0.26 0.05 0.77 96

B78 14 CH 22 0 0.64 103

B79 3 CH 17 55 21 34 -0.12 99

B79 9 CH 16 57 20 37 -0.11 4.00 99 99

B79 14 CH 21 0 0.67 102

B80 0 - 2 CL 0

B80 5 CH 21 53 22 31 -0.03 100

B80 7 CH 23 0 0.64 103

B80 11 CL 24 47 20 27 0.15 0.68 101 95

C - 6

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B81 3 CH 15 53 25 28 -0.36 99

B81 7 CH 18 56 22 34 -0.12 2.40 98

B81 9 CL 22 45 19 26 0.12 0.68 100 100

B81 13 CL 20 0 102

B82 3 CH 17 58 22 36 -0.14 100

B82 9 CH 22 0 0.68 100

B82 11 CH 19 53 21 32 -0.06 99

B82 13 CH 21 0 0.67 101

B83 5 CL 19 0 0.53 110

B83 7 CL 17 34 19 15 -0.13 92

B83 9 CL 18 0 0.64 103

B84 3 CL 18 40 18 22 0.00 95

B84 7 CL 21 36 17 19 0.21 96

B84 12 CL 23 36 18 18 0.28 0.64 103 97

B85 5 CL 14 37 17 20 -0.15 99

B85 13 CL 21 31 19 12 0.17 89

B86 0 - 4 CL 0

B86 9 CL-ML 31 28 22 6 1.50 98

B86 12 CL-ML 31 0 0.30 0.06 0.93 88

B87 5 CL 12 39 21 18 -0.50 97

B87 11 CL 20 46 18 28 0.07 99

B88 3 CH 18 51 15 36 0.08 4.80 94 99

B88 7 CH 20 0 0.28 0.06 0.67 102

B88 11 CH 23 50 26 24 -0.13 100

B89 1 CL 10 41 21 20 -0.55 97

B89 7 CH 24 57 24 33 0.00 0.83 92 100

B89 13 CH 24 52 22 30 0.07 0.93 88 100

B90 3 ML 8 21 19 2 -5.50 80

B90 7 CH 21 60 22 38 -0.03 0.63 4.10 95 66

B90 9 CH 20 0 103

B91 5 CL 14 30 18 12 -0.33 99

B91 11 CL 22 43 19 24 0.13 0.65 102 100

B92 1 CH 15 50 24 26 -0.35 96

B92 7 ML 9 22 19 3 -3.33 82

B92 11 CH 27 54 24 30 0.10 98

B93 3 CH 16 55 21 34 -0.15 100

B93 9 CH 26 56 20 36 0.17 0.73 98 100

B93 13 CL-ML 17 24 19 5 -0.40 90

B94 0 - 6 CL 0

B94 7 ML 7 24 23 1 -16.00 89

B94 9 CL 18 41 18 23 0.00 99

C - 7

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B95 1 CL 9 37 18 19 -0.47 95

B95 7 CL 13 38 22 16 -0.56 94

B95 11 CH 21 0 0.24 0.04 0.72 99

B95 13 CH 22 52 22 22 0.00 0.76 96 100

B96 5 CH 17 51 22 29 -0.17 100

B96 11 CL 16 44 19 25 -0.12 3.20 96 99

B96 15 CL 21 0 0.68 100

B97 3 CL 21 46 18 28 0.11 0.64 103 99

B97 5 CL 12 30 17 13 -0.38 92

B97 11 CH 26 50 19 31 0.23 0.74 97 100

B98 7 CL 18 35 18 17 0.00 2.70 98 99

B98 11 CL 28 0 0.81 94

B98 13 CL 20 38 18 20 0.10 0.63 104 97

B99 3 CL 17 39 21 18 -0.22

B99 7 CL 14 35 22 13 -0.62 99

B99 9 ML 5 25 24 1 -19.00 70

B100 5 CH 10 54 24 30 -0.47 100

B100 14 CH 10 55 19 36 -0.25 0.54 110 100

B101 1 CL 12 37 23 14 -0.79 97

B101 9 CH 20 58 24 34 -0.12 3.20 108 100

B101 12 CH 23 0 0.70 99

B102 0 - 6 CL 0

B102 7 CH 22 52 22 30 0.00 99

B102 9 CH 23 68 19 49 0.08 0.70 99 100

B102 11 CH 22 0 0.34 0.06 0.86 92

B103 5 CL 15 38 18 20 -0.15 5.60 101 100

B103 11 CH 24 70 23 47 0.02 0.85 91 100

B103 13 CH 22 0 0.72 98

B104 7 CL 15 48 23 25 -0.32 96

B105 3 CL 13 44 24 20 -0.55 95

B105 9 CH 19 57 20 37 -0.03 2.40 88 100

B105 12 SP-SC 9 32 18 14 -0.64 9

B106 7 CL 15 47 27 20 -0.60 91

B106 9 CH 16 0 0.19 0.06 0.57 108

B106 12 CH 16 55 27 28 -0.39

B107 5 CH 14 50 27 23 -0.57 99

B107 9 CL 11 40 19 21 -0.38 93

B107 11 CL 13 38 23 15 -0.67 0.72 98

B108 3 CL 11 40 24 16 -0.81 90

B108 9 CL 8 36 22 14 -1.00 98

B108 11 CL 9 32 20 12 -0.92 96

B108 12 - 14 SP-SC 0

C - 8

DONNA PUMP TO BROWNSVILLE LEVEE

Void Ratio γ

%w LL PL PI LI Cc Cr e C Φ (ave) -200

APPENDIX C

Soil Properties Summary

Bore Depth Description

B109 0 - 2 CL 0

B109 3 CL-ML 12 27 22 5 -2.00 98

B109 9 CL 15 43 20 23 -0.22 82

B110 5 CL 12 31 20 11 -0.73 91

B110 12 CL 16 42 19 23 -0.13 2.40 94 99

B111 0 - 2 CL 0

B111 3 ML 7 25 22 3 -5.00 56

B111 7 CL 11 32 18 14 -0.50 88

B111 11 CL 8 29 21 8 -1.63 92

B111 13 CL 19 45 20 25 -0.04 0.59 106 99

B112 1 CL 11 42 22 20 -0.55 92

B112 7 CL 12 33 18 15 -0.40 96

B112 13 CL 17 0 0.60 105

B113 5 CL 21 47 19 28 0.07 0.65 102 100

B113 11 CL 24 0 0.71 100

B113 12 - 14 ML 0

B114 3 CL 13 0 93

B114 5 CL 19 0 0.13 0.03 0.62 105

B114 7 CL 14 31 18 13 -0.31 90

B114 11 ML 6 25 23 2 -8.50 83

B115 1 CL 14 0 95

B115 5 CL 13 33 23 10 -1.00 98

B116 5 CL 14 32 22 10 -0.80 99

B117 3 CL 10 34 20 14 -0.71 91

B117 9 CL 10 34 22 12 -1.00 100

B117 13 SC-SM 2 21 15 6 -2.17 37

B118 1 CL 12 40 19 21 -0.33 100

B118 7 CL 10 34 20 14 -0.71 98

B118 14 ML 7 24 22 2 -7.50 50

B119 5 CL 16 46 27 19 -0.58 97

B119 9 CH 24 53 24 29 0.00 99

B119 11 CH 24 0 0.25 0.08 0.69 101

B119 13 CH 20 50 20 30 0.00 0.62 104 100

B120 7 CL 37 36 22 14 1.07

B120 11 CH 20 51 22 29 -0.07 101 100

B121 0 - 2 CL 0

B121 3 CL 4 16 16 0 94

B121 7 CL 12 43 20 23 -0.35 40

B121 13 CL 10 28 18 10 -0.80 74

B122…