Attachment 1 - Govt Questions to Industry.pdf

PDF 20 MB Posted Mar 7, 2024

Attached to: Updated-White Paper to Industry-REQUEST FOR INFORMATION For Modified Central City, North Bypass Channel, Fort Worth, Texas
Solicitation number: Not on record
Issued by: Department of the Army Corps of Engineers Engineering District Fort Worth

About this file

Written by GovTribe AI · Mar 7, 2024

This document is a Request for Information from the U.S. Army Corps of Engineers Fort Worth District regarding construction of the Modified Central City North Bypass Channel project in Fort Worth, Texas. The project scope involves construction of approximately 3,900 feet of bypass channel with a floodwall on the east side and earthen levee on the west side. Estimated quantities include over 545,000 cubic yards of soil excavation and 200,000 cubic yards of rock excavation via blasting and ripping. Other major elements are approximately 5,050 feet of floodwall, 4,500 feet of levee, and 40,000 cubic yards of structural concrete excluding paving. The estimated construction price range is $100-250 million with a duration of 2-2.5 years. Interested prime contractors are requested to respond by March 21, 2024 identifying bonding capacity of at least $100 million and experience on similar projects. The Corps intends to meet with the first ten respondents to discuss questions in Attachment 1. The estimated solicitation date is November 2024 with proposals due in January 2025.

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BCN RFI 0001 to Industry White Paper - Sections 00 21 00 and 00 22 16.pdf	PDF	Jul 24, 2024
Attachment 2 - Draft Specification Sections.pdf	PDF	Mar 7, 2024

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Attachment 1

Government Questions to Industry

The following questions are intended to assist in the design and acquisition for the subject project. The Government is looking for both positive and negative feedback on the questions below.

1. Given the site location and quantity of materials answer the following:

a. For the approximately 40,000 cubic yards of concrete required, would you set up an on-site batch plant or procure the concrete from a local vendor?

b. There is approximately 70,000-80,000 cubic yards of channel riprap.

The project would like to reuse the approximately 200,000-250,000 cubic yards of excavated rock from the channel excavation to use as channel riprap in certain areas (D50 sizes,15 -18-in) with the potential to reuse the excavated rock as base course material. Based on the quantity of excavated rock, would you set up an onsite crushing operation? Are there any concerns with this approach?

2. The project will have rock cuts approximately 5 - 15 feet. The rock is a combination of limestone and interbedded shale seams. The Government anticipates that most of the rock removal will be possible with ripping and other mechanical methods. However, blasting will be permitted in locations where ripping is not cost effective. A seismic refraction tomography (SRT) survey has been performed along most of the bypass channel alignment to supplement rock coring data obtained from the test borings. Based on the SRT survey, the seismic velocity of the bedrock is typically within a range of 5,000 to 12,000 feet per second (ft/s) with an assumed top of bedrock between 5,000 and 6,500 ft/s based on correlations with the test boring data. See the Subsurface Investigation Report, Phase III – North Bypass Channel for reference.

a. What size of dozer would you recommend?

b. Do you have a recommended threshold point when blasting will become more economical?

c. The edge of the rock cut needs to be reasonably controlled, as the limits of the channel need to be held. The rock on the outside of the excavated area cannot be disturbed. Is presplitting the most economical means to maintain and control the edge of the rock cut or is there a recommended alternative? What alternative would you want to allow in addition to pre-splitting?

3. Is there any information not included in the Subsurface Investigation Report, Phase III – North Bypass Channel that the Government should consider providing as part of the solicitation?

4. The project will have a large amount of planting, and some of the species may require plants to be grown. As such, the contract will have a specification for contract-grown plants, if needed. The plantings for this project are native species, which should be readily available in the trade and include:

For the soft edge:

• AROMATIC SUMAC / RHUS AROMATICA

• AUTUMN SAGE / SALVIA GREGGII

• PALE LEAF YUCCA / YUCCA PALLIDA

• SOTOL / DASYLIRION WHEELERI

• TEXAS LANTANA / LANTANA HORRIDA

• TEXAS SAGE / LEUCOPHYLLUM FRUTESCENS 'SIVERADO'

• TURK`S CAP / MALVAVISCUS DRUMMONDII

For the hard edge:

• AROMATIC SUMAC / RHUS AROMATICA

• AUTUMN SAGE / SALVIA GREGGII

• BLACK-EYED SUSAN / RUDBECKIA HIRTA

• BLACKFOOT DAISY / MELAMPODIUM LEUCANTHUM

• BLUE MISTFLOWER / EUPATORIUM COELESTINUM

• BLUE GRAMA / BOUTELOUA GRACILIS

• BLUE MISTFLOWER / EUPATORIUM COELESTINUM

• BRAKELIGHTS RED YUCCA / HESPERALOE PARVIFLORA

`BRAKELIGHTS’

• DWARF WAX MYRTLE / MYRICA CERIFERA

• DWARF YAUPON / ILEX VOMITORIA `NANA`

• EL TORO MUHLY / MUHLENBERGIA EMERSLEYI `EL TORO`

• GULF COAST MUHLY / MUHLENBERGIA CAPILLARIS `GULF COAST`

• INLAND SEA OATS / CHASMANTHIUM LATIFOLIUM

• LINDHEIMER`S MUHLY / MUHLENBERGIA LINDHEIMERI

• MEALY BLUE SAGE / SALVIA FARINACEA

• PRARIE WILDRYE / ELYMUS CANADENSIS

• RED YUCCA / HESPERALOE PARVIFLORA

• SCARLET SAGE / SALVIA COCCINEA

• SEEP MUHLY / MUHLENBERGIA REVERCHONI

• TEXAS LANTANA / LANTANA HORRIDA

• TEXAS SAGE / LEUCOPHYLLUM FRUTESCENS 'COMPACTA'

Plugs proposed for the soft edge (approximately 200-300 of each species):

• ANTELOPE HORN MILKWEED / ASCLEPIAS ASPERULA

• BUTTERFLY MILKWEED / ASCLEPIAS TUBEROSA

• FROG FRUIT / PHYLA NODIFLORA

• GREEN MILKWEED / ASCLEPIAS VIRIDIS

• GREENTHREAD / THELESPERMA FILIFOLIUM

• HALBERDLEAVED ROSEMALLOW / HIBISCUS LAEVIS

• LEAVENWORTH`S ERYNGO / ERYNGIUM LEAVENWORTHII

• LITTLE BLUESTEM GRASS / SCHIZACHYRIUM SCOPARIUM

• PITCHER SAGE / SALVIA AZUREA

• SHOWY MILKWEED / ASCLEPIAS SPECIOSA

• SIDE OATS GRAMA / BOUTELOUA CURTIPENDULA

• SWAMP MILKWEED / ASCLEPIAS INCARNATA

• SWITCH GRASS / PANICUM VIRGATUM `UPLAND`

• TEXAS CUPGRASS / ERIOCHLOA SERICEA

• UPRIGHT PRAIRIE CONEFLOWER / ATIBIDA COLUMNIFERA

• WHITE TRIDENS / TRIDENS ALBESCENS

• ZEXMENIA / ZEXMENIA HISPIDA `DEVIL`S RIVER`

a. Based on the lists above, are there any species that the Contractor would anticipate having availability problems?

b. Are these plants commercially available?

c. If not, could the plants be grown as part of the contract and within the estimated period of performance?

5. Integral color concrete or warm-toned aggregate concrete is being considered to help provide a more uniform appearance to the exposed portions of the cast-in-place walls. There are concerns with the overall improvement in uniformity.

a. What challenges would have to be overcome with either method (i.e., warm tone aggregate or integral color) for a project of this size?

b. If only one were to be chosen, which would be more economical?

c. Do you have any lessons learned from other projects to share (i.e., specific specification requirements to include or not include)?

6. What are the biggest risk factors that affect pricing?

7. What are recommendations to help manage contractor risk and allow for risk sharing between parties?

8. Do you have any other comments about these features or recommendations on things to consider?

Subsurface Investigation Report, Phase III – North Bypass Channel

Upper Trinity River Central City

Fort Worth, Texas

Subsurface Investigation Report

Phase III - North Bypass Channel

26 July 2018

Prepared for:

U.S. Army Corps of Engineers

Fort Worth District

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FINAL

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Table of Contents

Section 1 - Introduction

1.1 Background ................................................................................................................................................. 1-1

1.2 Project Description .................................................................................................................................. 1-1

1.3 Project Datum ............................................................................................................................................. 1-2

1.4 Purpose and Scope ................................................................................................................................... 1-2

1.4.1 Purpose ............................................................................................................................................. 1-2

1.4.2 Scope .................................................................................................................................................. 1-2

1.4.3 Development of Work Plan ...................................................................................................... 1-2

1.5 Report Limitations ................................................................................................................................... 1-3

Section 2 - Site and Subsurface Conditions

2.1 Subsurface Investigation Programs .................................................................................................. 2-1

2.1.1 Geophysical Exploration Program ........................................................................................ 2-1

2.1.2 Test Boring Program ................................................................................................................... 2-1

2.2 Geotechnical Laboratory Testing ....................................................................................................... 2-3

2.3 Subsurface Conditions ............................................................................................................................ 2-4

2.3.1 General .............................................................................................................................................. 2-4

2.3.2 Subsurface Conditions ................................................................................................................ 2-4

2.3.2.1 Fill ......................................................................................................................................... 2-4

2.3.2.2 Native Clay ........................................................................................................................ 2-4

2.3.2.2.1 Clay Sublayer ................................................................................................ 2-9

2.3.2.2.2 Sand & Clay Sublayer ................................................................................. 2-9

2.3.2.3 Sand & Gravel .................................................................................................................. 2-9

2.3.2.4 Weathered Rock ............................................................................................................. 2-9

2.3.2.5 Bedrock ............................................................................................................................2-10

2.4 Groundwater Conditions .....................................................................................................................2-10

2.5 Expected Variation in Subsurface Conditions ............................................................................2-10

Table of Contents • Geotechnical Data Report ii

Appendices

Appendix A – Geophysical Exploration Report

Appendix B – Test Boring Logs

Appendix C – Rock Core Photo Logs

Appendix D – Geotechnical Laboratory Test Results

Tables

Table 2-1 Summary of Geotechnical Laboratory Index Test Results .............................................. 2-5

Table 2-2 Summary of Geotechnical Laboratory Rock Test Results................................................ 2-6

Table 2-3 Summary of Subsurface Investigation Program .................................................................. 2-8

Figures

Figure 2-1 Test Boring Location Plan ........................................................................................................... 2-2

1-1

Section 1

Introduction

1.1 Background

CDM-Stanley Joint Venture (CDM-Stanley) has been retained by the United States Army Corps of

Engineers - Fort Worth District (USACE) and the Tarrant Regional Water District (TRWD) to provide engineering services for the Fort Worth Central City (FWCC) bypass channel north segment under

Contract No. W916G-11-D-0027, Task Order No. 0007. After review of the existing data sets for the

FWCC North Segment, CDM-Stanley identified several geotechnical risks associated with data gaps related to the previous field investigations and laboratory testing programs for the north segment of the bypass channel. The previous subsurface investigation programs were developed by CDM Smith, USACE and its subconsultants under separate contracts between 2004 and 2012.

The CDM-Stanley technical memorandum titled Proposed Geotechnical Risk Mitigation Program, Fort

Worth Central City Bypass Channel North Segment revised 1 June 2017 summarizes the geotechnical project risks identified during the 30% and 60% design stages, proposed geotechnical risk mitigation program and methods for implementing the additional data into the detailed design and preparation of the contract documents. As a part of the geotechnical risk mitigation program, the Phase 3 supplemental geotechnical investigation has been implemented consisting of a geophysical exploration, targeted subsurface exploration (test boring) program and geotechnical laboratory testing. This report presents the results of the Phase 3 supplemental geotechnical investigation program that were conducted to obtain additional subsurface and laboratory testing data for the proposed construction.

1.2 Project Description

The FWCC bypass channel project consists of developing contract documents to construct a bypass channel on the Trinity River located north of downtown Fort Worth. The bypass channel is proposed to consist of north and south segments that total approximately 8,400 feet in length. Note that this report only discusses the results of the Phase 3 supplemental geotechnical investigation for the north segment of the bypass channel. Results of previous investigations programs are provided in separate reports.

The north segment of the bypass channel is approximately 4,000 feet in length and includes construction of a levee on the western side of the channel and a retaining wall on the eastern side of the channel. The proposed levee embankment is approximately 4,700 feet in length, and the top of the levee varies between approximately 9 feet below and 19 feet above existing grade at the site. The average raise-in-grade associated with the levee is approximately 15 feet. The proposed retaining wall is approximately 4,000 feet in length of which approximately 3,100 feet (80% of the wall) is proposed to be founded on shallow mat foundations bearing directly on bedrock based on the 60% submittal design documents. The retaining wall bottom of slab (BOS) increases from elevation (El.) 511 to 516 between the northern and southern extents of the north segment of the project site.

Section 1 • Introduction

1-2

1.3 Project Datum

Unless otherwise indicated, all boring coordinates noted herein are in feet and referenced to the North

American Datum 1983 (CORS), Texas State Plane Coordinate System, North Central Zone (4202). All elevations noted herein are in feet and referenced to the North American Vertical Datum of 1988

(NAVD 88). Horizontal and ground surface elevations were measured to an accuracy of 0.1 feet in horizontal and 0.01 feet in the vertical.

The test boring locations were surveyed by a land surveyor registered in the State of Texas. The survey was performed by ARS Engineers, Inc. (ARS) of Dallas, Texas.

1.4 Purpose and Scope

1.4.1 Purpose

This geotechnical data report presents the results of the Phase 3 supplemental field and laboratory testing investigations for use with existing data in furthering the design of the north segment of the bypass channel and its associated structures. The geophysical testing, test boring locations, sampling and laboratory testing associated with this investigation were selected to supplement the existing overburden and bedrock data in areas where a review of the existing data indicated more subsurface information was prudent for the design of the north segment of the bypass channel, retaining walls and levee sections. Geotechnical investigations completed to date (including the current investigation) have been performed under the input and guidance of USACE staff. The analysis and compilation of all the geotechnical investigations will be conducted separately during development of the individual project feature Design Documentation Report (DDR), which is outside of the scope of this report.

1.4.2 Scope

CDM-Stanley’s scope of work included the following:

Review existing subsurface and laboratory testing data and the proposed contract documents to identify data gaps and areas where additional overburden or rock information is recommended;

Conduct a subsurface exploration program consisting of five (5) geophysical test lines and eleven (11) test borings (CC17-120 through CC17-129 and CC17-129A) to evaluate subsurface conditions and obtain soil and rock samples for geotechnical laboratory testing;

Conducting geotechnical laboratory tests on select soil and bedrock samples to assist with the classification of soils and bedrock encountered and to estimate the engineering properties of the overburden soils and bedrock;

Prepare test boring logs; and

Prepare this Geotechnical Data Report (GDR) summarizing the geotechnical data collected as part of the Phase 3 subsurface exploration program including field observations of soil and bedrock, groundwater levels and laboratory testing results.

1.4.3 Development of Work Plan

After review and modification of the Phase 3 supplemental subsurface exploration program and proposed laboratory testing by the USACE, a final work plan was prepared. The work plan is summarized in the risk mitigation technical memorandum discussed above.

Section 1 • Introduction

1-3

This GDR provides record of all field observations and laboratory test results associated with the

Phase 3 supplemental geotechnical investigation.

1.5 Report Limitations

The data contained in this report have been prepared for the design of the proposed FWCC bypass channel north segment located north of downtown Fort Worth, Texas as understood at this time and described in this report. This report has been prepared in accordance with generally accepted engineering practices. No other warranty, express or implied, is made. In the event that changes in design or location of the proposed improvements occur, the data contained herein should not be considered valid unless verified in writing by CDM-Stanley.

2-1

Section 2

Site and Subsurface Conditions

2.1 Subsurface Investigation Programs

The Phase 3 geotechnical investigation programs completed by CDM-Stanley were conducted to investigate subsurface conditions along the north segment of the bypass channel. The subsurface investigation programs consisted of a geophysical survey, including five (5) electrical resistivity topography (ERT) and seismic refraction tomography (SRT) test lines. After review of the preliminary geophysical exploration program results and the existing test boring data, eleven (11) additional test borings (CC17-120 through CC17-129 and CC17-129A) were conducted at locations where the geophysical exploration identified anomalies and where additional subsurface data would supplement previous data or fill existing data gaps.

The approximate subsurface test boring locations are shown on Figure 2-1.

2.1.1 Geophysical Exploration Program

CDM-Stanley subcontracted Gehrig, Inc. of Muenster, Texas to perform a geophysical survey consisting of ERT and SRT to create a near continuous subsurface profiles along portions of the bypass channel north segment. The geophysical survey data results include the soil and bedrock lithology, groundwater elevation, top of bedrock and seismic velocities. The geophysical exploration included two (2) geophysical test lines that ran the majority of the bypass channel north segment length along the hard edge and channel centerline alignments. In addition, three (3) geophysical test lines running perpendicular to the bypass channel alignment were conducted. These perpendicular test lines were located near the north and south ends of the segment and one near the middle of the north segment.

The hard edge and channel centerline geophysical test lines were not completed in the vicinity of

Commerce Street due to vehicular traffic and the Contractor staging area associated with the ongoing

Main Street Bridge construction. From Sta. 2+90 to Sta. 12+64, the channel centerline geophysical test line was offset towards the east due to access limitations through the TRWD maintenance yard.

The as-surveyed geophysical test lines and results of the geophysical exploration conducted by Gehrig, Inc. (Gehrig) are discussed in the report prepared by Gehrig included in Appendix A.

2.1.2 Test Boring Program

The test borings were drilled using a truck-mounted CME-75 drill rig, drilled by Texplor of Dallas, Inc.

(Texplor) of Dallas, Texas. All test borings were conducted between December 13 and 18, 2017 and

January 8 and 9, 2018. All test borings were drilled using 6 5/8-inch inside diameter (ID) hollow stem augers. The test borings were drilled to depths ranging from 14.5 and 39.8 feet below existing ground surface (bgs). Test boring CC17-129 was terminated at 14.5 feet bgs due to petroleum odor and offset approximately 5 feet as CC17-129A, which was augered directly to 14.5 feet bgs. Ground surface elevations at the test boring locations ranged from El. 519.5 to El. 535.3.

Soil sampling was conducted continuously to the top of bedrock (TOR), and rock coring was performed continuously thereafter. Split spoon sampling of granular (cohesionless) soils was

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Texas # 124499, 09/01/17

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LEGEND

GROUND SURFACE ELEVATIONS:

THE FOLLOWING TABLE PROVIDES THE BORING NORTHING AND EASTING AND 4.

ARS ENGINEERS, INC. OF DALLAS, TEXAS.

THE TEST BORING LOCATIONS WERE SURVEYED AFTER OR DURING DRILLING BY 3.

SYSTEM, NORTH CENTRAL ZONE (4202).

TO THE NORTH AMERICAN DATUM 1983 (CORS), TEXAS STATE PLAN COORDINATE

ALL TEST BORING COORDINATES NOTED HEREIN ARE IN FEET AND REFERENCED 2.

VERTICAL DATUM OF 1988 (NAVD88).

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Section 2 • Site and Subsurface Conditions

2-3 conducted in accordance with ASTM D1586 (using 2.0-inch outside diameter (O.D.) sampler, driven 18 inches by blows from a 140-pound hammer falling freely for 30 inches). The number of blows required to drive the sampler each 6-inch increment was recorded and the Standard Penetration

Resistance (N-value) was determined as the sum of the blows over the bottom 12-inches of penetration. When a refusal condition (i.e., split spoon driven less than 6 inches for 50 blows) was encountered, the number of blows with the corresponding depth of penetration was recorded. A CDM

Smith representative visually classified the soil samples recovered in the field in general accordance with the Burmister classification system and assigned a Unified Soil Classification System (USCS) classification. Representative soils samples from each split spoon were collected and stored in plastic bags for subsequent review and geotechnical laboratory testing.

Undisturbed tube sampling of fine-grained (cohesive) soils were collected in the test borings in general accordance with ASTM D1587 using a hydraulically pushed Shelby tube sampler. The Shelby tube samples were extruded in the field, wrapped in aluminum foil and sealed with both tape and plastic bags for subsequent review and laboratory testing. A CDM Smith representative visually classified the soil samples recovered in the field in general accordance with the Burmister classification system and assigned a USCS classification. Representative soils samples from each

Shelby tube were collected and stored in plastic bags for subsequent review and geotechnical laboratory testing.

Rock coring was conducted using 4-inch ID double-tube rock coring techniques in accordance with

ASTM D2113. Core samples were classified in the field and the descriptions included percent recovery and rock quality designation (RQD), where applicable. The RQD was determined for each core run by dividing the total recovered length of the rock segments longer than four inches over the total length of the core run. The time to advance each foot of rock core was also recorded during the rock coring process.

Groundwater levels at the test boring locations were estimated from the condition of the samples obtained and by the observed water levels within the borehole at the time of drilling.

All test borings were backfilled with cement-bentonite grout to the ground surface.

The test boring locations were surveyed by ARS and are shown on Figure 2-1. The test boring logs, prepared by CDM Smith, are included in Appendix B. The rock core photo logs, prepared by CDM

Smith, are included in Appendix C.

2.2 Geotechnical Laboratory Testing

Geotechnical laboratory tests were performed on select soil samples and rock cores obtained from the subsurface investigation program. All geotechnical laboratory tests were performed by GeoTesting

Express, Inc. of Acton, Massachusetts and consisted of the following:

Soil Sample Testing o Seventeen (17) Grain Size Analyses with Hydrometer in accordance with ASTM D6913 and ASTM D7928; and o Ten (10) Atterberg Limits Tests in accordance with ASTM D4318.

Rock Core Testing

2-4 o Four (4) Uniaxial Compressive Strength of Intact Rock Cores in accordance with ASTM

D7012 Method C;

o Two (2) Elastic Moduli of Intact Rock Core Specimens in Uniaxial Compression in accordance with ASTM D7012 Method D;

o Two (2) Direct Shear of Shale Test (2 Points) in accordance with ASTM D5607;

o Five (5) Splitting Tensile Tests in accordance with ASTM D3967;

o Ten (10) Slake Durability Tests in accordance with ASTM D4644;

o Ten (10) Axial Point Load Strength Tests in accordance with ASTM D5731; and o Two (2) Abrasivity (CERCHAR) Tests in accordance with ASTM D7625.

A summary of the geotechnical laboratory index test results is presented in Table 2-1. A summary of the rock testing results is presented in Table 2-2. All geotechnical laboratory test results are included in Appendix D.

2.3 Subsurface Conditions

2.3.1 General

Subsurface soil conditions were interpreted from the test borings conducted as part of the subsurface investigation program, geotechnical laboratory test results and our understanding of the regional geology. The test borings typically encountered Fill, over Native Clay including the Clay sublayer underlain by the Sand & Clay sublayer, Sand & Gravel, Weathered Rock and Bedrock. A summary of soil, bedrock and groundwater conditions encountered in the test borings is included in Table 2-3.

2.3.2 Subsurface Conditions

2.3.2.1 Fill

The Fill layer was encountered at the ground surface at test boring locations CC17-121 and CC17-127.

The layer was approximately 4 feet thick at test boring CC17-121 and 2.5 feet thick at test boring

CC17-127. The material typically consisted of dry, brown and black, CLAY & SILT, “little” to “and” fine to coarse sand, “little” to “no” fine gravel or dry, gray and brown, fine to course SAND, “little” to “and” gravel, “little” to “trace” clay & silt. SPT N-values in the Fill layer ranged from 51 blows per foot (bl/ft) to 62 bl/ft with an average value of 57 bl/ft at the test boring locations.

Pocket penetrometer readings of samples collected in the Fill layer ranged from 1.0 ton per square foot (tsf) to 3.0 tsf with an average of 2.0 tsf.

2.3.2.2 Native Clay

The Native Clay layer consists of undisturbed, naturally-deposited clays located outside of the limits of existing fill areas such as the levees. The Native Clay layer has been separated into two distinct sublayers that may not have been previously identified during previous investigations due to the soil sampling intervals previously conducted on the project. The layer is separated into an upper Clay sublayer that typically consisted of fine-grained soils (i.e., clay and silt) with little to trace sand and gravel and a lower Sand & Clay sublayer that typically consisted of coarse-grained soils (i.e., fine to medium sand) with and to little fines.

CC17-120 ST-3 Clay CL Lean Clay 12 41 14 27 0.0 14.2 85.8

CC17-120 SPT-1 Sand & Gravel -- -- -- -- -- -- 42.4 39.5 18.1

CC17-121 ST-9 Sand & Clay CL Sandy Lean Clay 14 24 14 10 0.0 40.1 59.9

CC17-122 ST-6 Clay CL Lean Clay with Sand 15 43 14 29 0.0 24.3 75.7

CC17-122 SPT-3 Sand & Gravel -- -- -- -- -- -- 37.5 50.3 12.2

CC17-123 SPT-1 Sand & Clay SC Clayey Sand 10 21 13 8 1.8 55.8 42.4

CC17-123 SPT-3 Sand & Gravel -- -- -- -- -- -- 49.1 42.1 8.8

CC17-124 ST-8 Clay CL Lean Clay with Sand 16 40 15 25 0.0 25.7 74.3

CC17-124 SPT-3 Sand & Gravel -- -- -- -- -- -- 47.3 46.7 6.0

CC17-125 SPT-3 Sand & Clay SM Silty Sand 20 NV NP NP 0.5 63.2 36.3

CC17-126 ST-1 Clay GC Clayey Gravel with Sand 13 34 23 11 44.9 34.2 20.9

CC17-126 SPT-2 Sand & Gravel -- -- -- -- -- -- 36.4 50.3 13.3

CC17-127 ST-4 Clay CL Lean Clay with Sand 20 39 16 23 0.0 26.1 73.9

CC17-128 ST-8 Sand & Clay CL Sandy Lean Clay 14 27 13 14 0.0 37.4 62.6

CC17-128 SPT-3 Sand & Gravel -- -- -- -- -- -- 30.2 61.8 8.0

CC17-129 ST-5 Clay CL Lean Clay 15 39 16 23 0.0 11.6 88.4

CC17-129A SPT-1 Sand & Gravel -- -- -- -- -- -- 38.7 54.0 7.3

Notes: Abbreviations:

1 USCS classifications were performed in accordance with ASTM D2487. -- Test Not Performed

2 Moisture content tests were performed in accordance with ASTM D2216. LL Liquid Limit 3 Atterberg Limit tests were performed in accordance with ASTM D4318. PL Plastic Limit 4 Sieve analyses performed in accordance with ASTM D6913 and ASTM D7928. PI Plasticity Index

NP Non-Plastic NV No Value

USCS Unified Soil Classification

System

United States Army Corps of Engineers

Fort Worth Central City

Fort Worth, Texas

Table 2-1

Summary of Geotechnical Laboratory Index Test Results

Bypass Channel North Segment

Phase 3 Supplemental Geotechnical Investigation

Test Boring

Number

Sample

Number

Sample Depth

(ft)

USCS

Classification (1)

Sieve Analysis (4)

% Sand

Moisture

Content (2)

Atterberg Limits (3)

PILL PL

Strata

% Silt and Clay

USCS

Classification

Description

(1) % Gravel

2.0 - 3.0

12.0 - 13.5

7.0 - 8.0

9.0 - 10.4

12.0 - 13.0

5.0 - 6.0

12.0 - 13.5

9.0 - 10.5

14.0 - 15.5

6.0 - 7.5

0.0 - 1.0

10.5 - 12.0

3.0 - 4.0

7.0 - 8.0

12.0 - 13.5

4.0 - 5.0

14.5 - 16.0

7/20/2018

Method C (1)

Method D

(2) Failure Load

(lbs)

Estimated

Compressive

Strength (psi)

CC17-120 RC-1 13.7 - 14.1 Limestone -- -- -- -- 165 -- -- -- -- -- -- -- Intact Material Failure

CC17-120 RC-1 15.1 - 17.5

Limestone

Interbedded with

Shale Seams

3,265 -- -- -- -- -- -- -- -- -- -- -- Intact Material Failure, Discontinuity Failure

CC17-120 RC-2 19.8 - 20.8 Limestone -- -- -- -- -- 24.6 280 4.9 110 -- -- --

CC17-120 RC-3 23.3 - 25.3

Limestone

Interbedded with

Shale Seams

-- -- 1,295 3,810 -- -- -- -- -- 97.6 -- -- Intact Material Failure

CC17-120 RC-3 26.2 - 27.5 Shale -- -- 1,589 3,940 -- -- -- -- -- 71.7 -- -- Intact Material Failure

CC17-121 RC-2 25.6 - 28.0

Limestone

Interbedded with

Shale Seams

-- -- 1,254 3,510 -- -- -- -- -- 96.0 -- -- Intact Material Failure

CC17-121 RC-2 29.5 - 30.0 Shale -- -- -- -- 352 -- -- -- -- -- -- -- Intact Material Failure

CC17-122 RC-2 22.5 - 25.3

Limestone

Interbedded with

Shale Seams

-- -- 919 2,710 -- -- -- -- -- 95.9 -- --

CC17-123 RC-1 19.8 - 20.9 Limestone -- -- -- -- -- -- -- -- -- -- 0.88 Low Abrasiveness

CC17-123 RC-1 20.9 - 22.5 Limestone 5,131 -- -- -- -- -- -- -- -- -- -- -- Intact Material Failure, CC17-123 RC-2 23.2 - 25.4

Limestone

Interbedded with

Shale Seams

-- -- 832 N/A -- -- -- -- -- 94.7 -- -- Discontinuity Failure

CC17-124 RC-1 20.6 - 21.4 Limestone -- -- -- 216 -- -- -- -- -- -- -- Intact Material Failure

CC17-124 RC-1 22.4 - 23.5 Limestone -- -- 1,061 2,840 -- -- -- -- -- 97.5 -- -- Intact Material Failure

CC17-124 RC-2 24.0 - 25.3

Limestone

Interbedded with

Shale Seams

-- 3,491 -- -- -- -- -- -- -- -- -- --

Peak

Friction

Angle (°)

CERCHAR Index

Classficiation

Abrasivity (7)

United States Army Corps of Engineers

Table 2-2

Summary of Geotechnical Laboratory Rock Test Results

Bypass Channel North Segment

Fort Worth, Texas

Fort Worth Central City

Phase 3 Supplemental Geotechnical Investigation

Test Boring

Number

Direct Shear (5)

Post-Peak

Cohesion

(psi)

Post-Peak

Friction

Angle (°)

Core

Run

Sample

Depth (ft) Rock Type

Uniaxial Compressive Strength

(psi) Axial Point Load

(3)

Strength Parameters

Splitting

Tensile

Strength

(psi) (4)

Average

CAI

Comments

Slake Durability

Index (%) (6)

Peak

Cohesion

(psi)

Method C (1)

Method D

(2) Failure Load

(lbs)

Estimated

Compressive

Strength (psi)

Peak

Friction

Angle (°)

CERCHAR Index

Classficiation

Abrasivity (7)

United States Army Corps of Engineers

Table 2-2

Summary of Geotechnical Laboratory Rock Test Results

Bypass Channel North Segment

Fort Worth, Texas

Fort Worth Central City

Phase 3 Supplemental Geotechnical Investigation

Test Boring

Number

Direct Shear (5)

Post-Peak

Cohesion

(psi)

Post-Peak

Friction

Angle (°)

Core

Run

Sample

Depth (ft) Rock Type

Uniaxial Compressive Strength

(psi) Axial Point Load

(3)

Strength Parameters

Splitting

Tensile

Strength

(psi) (4)

Average

CAI

Comments

Slake Durability

Index (%) (6)

Peak

Cohesion

(psi)

CC17-125 RC-1 10.5 - 11.1 Limestone -- -- -- -- -- -- -- -- -- -- 0.77 Low Abrasiveness Intact Material Failure

CC17-125 RC-1 11.1 - 12.0 Limestone -- -- -- -- 313 -- -- -- -- -- -- --

CC17-125 RC-2 15.5 - 17.2

Limestone

Interbedded with

Shale Seams

-- -- 1,461 3,990 -- -- -- -- -- 91.3 -- -- Intact Material Failure

CC17-125 RC-4 25.0 - 26.0 Shale -- -- -- -- -- 0 61

(8) 23.5 2.9 -- -- --

CC17-126 RC-1 16.5 - 17.7 Limestone 4,915 -- -- -- -- -- -- -- -- -- -- -- Intact Material Failure, CC17-127 RC-2A 24.1 - 26.0

Limestone

Interbedded with

Shale Seams

-- -- 715 2,050 -- -- -- -- -- 90.7 -- -- Intact Material Failure

CC17-127 RC-3 30.1 - 31.0

Limestone

Interbedded with

Shale Seams

-- -- 1,857 5,290 -- -- -- -- -- 95.9 -- -- Intact Material Failure

CC17-128 RC-1 18.1 - 19.7

Limestone

Interbedded with

Shale Seams

2,282 -- -- -- -- -- -- -- -- -- -- -- Intact Material Failure, Discontinuity Failure

CC17-128 RC-2 21.7 - 24.6

Limestone

Interbedded with

Shale Seams

-- -- 1,913 4,960 -- -- -- -- -- 92.4 -- -- Intact Material Failure

CC17-129A RC-2 20.8 - 23.3

Limestone

Interbedded with

Shale Seams

-- 4,290 -- -- -- -- -- -- -- -- -- --

CC17-129A RC-2 24.0 - 24.4 Shale -- -- -- -- 49 -- -- -- -- -- -- -- Discontinuity Failure

Notes: Abbreviations:

1. Uniaxial compressive strength conducted in accordance with ASTM D7012 Method C. -- Test Not Conducted

2. Elastic moduli in uniaxial compression test conducted in accordance with ASTM D7012 Method D. ft Foot

3. Axial point load test conducted in accordance with ASTM D5731. lbs Pounds

4. Splitting tensile strength test conducted in accordance with ASTM D3967. pcf Pounds per Cubic Foot

5. Direct shear test conducted in accordance with ASTM D5607. psi Pounds per Square Inch

6. Slake durability tests conducted in accordance with ASTM D4644. N/A Not Applicable, Invalid Test

7. Abrasivity (CERCHAR) tests conducted in accordance with ASTM D7625.

8. Peak cohesion interpreted by CDM Smith based upon laboratory test results.

Clay

Sublayer

Sand & Clay

Sublayer

CC17-120 528.7 32.5 NE 6.0 3.0 1.5 2.0 >20.0 516.2 516.2

CC17-121 535.3 35.0 4.0 8.0 5.5 NE 2.5 >15.0 515.3 516.8

CC17-122 531.2 32.0 NE 7.0 5.0 5.0 NE >15.0 514.2 517.7

CC17-123 530.3 33.0 NE 7.0 5.0 4.5 1.5 >15.0 512.3 516.8

CC17-124 529.8 33.5 NE 9.0 5.0 4.0 0.5 >15.0 511.3 515.8

CC17-125 519.5 29.3 NE 2.0 5.5 1.5 0.3 >20.0 510.2 513.5

CC17-126 523.3 34.3 NE 8.0 1.0 5.0 0.3 >20.0 509.0 516.3

CC17-127 530.1 34.0 2.5 6.5 8.0 1.5 0.5 >15.0 511.1 513.3

CC17-128 531.0 31.0 NE 7.0 3.8 4.2 1.0 >15.0 515.0 519.0

CC17-129 534.0 14.5 NE 7.7 3.8 >3.0 NE NE UNK NE

CC17-129A

(5) 534.0 39.8 Auger Auger Auger 3.0 1.9 >20.4 516.2 519.5

Notes:

1 Elevations are in feet and referenced to the North American Vertical Datum of 1988 (NAVD88).

2 Indicated depths are depths below ground surface at the time of drilling.

3 Groundwater levels were measured in the boreholes at the time of drilling and may not represent the stabilized groundwater level.

4 Top of bedrock was assumed based on depth of auger refusal.

5 CC17-129A was an offset boring for CC17-129, which was terminated due to a potential petroleum odor and was augered directly to 14.5 feet bgs.

Abbreviations:

> Indicates layer not fully penetrated

NE Not encountered

UNK Unknown

Auger Augered to 14.5 feet bgs. No samples collected.

BGS

Fill Weathered

Rock Bedrock

Native Clay

Below ground surface

Layer Thickness

(ft)

United States Army Corps of Engineers

Bypass Channel North Segment

Fort Worth, Texas

Table 2-3

Summary of Subsurface Investigation Program

Fort Worth Central City

Phase 3 Supplemental Geotechnical Investigation

Approximate Top of Bedrock

Elevation

(ft) (1)

Test Boring

Number

Groundwater

Elevation

(ft) (1&3)

Approximate

Ground Surface

Elevation

(ft) (1)

Exploration

Depth

(ft)

(2) Sand &

Gravel

2-9

2.3.2.2.1 Clay Sublayer

The Clay sublayer was encountered at all test boring locations except for test boring location CC17-

129A that was augered directly to 14.5 feet bgs. The sublayer ranged from approximately 2.0 to 9.0 feet thick at the test boring locations. The Clay sublayer typically consisted of moist, dark brown and gray, CLAY & SILT to Silty CLAY, “little” to “trace” fine to coarse sand, “little” to “no” fine gravel.

Pocket penetrometer readings of samples collected in the Clay sublayer ranged from 1.0 tsf to greater than 4.5 tsf with an average of 3.9 tsf.

Based on samples tested as part of this program, the liquid limit of the Clay sublayer ranged from 34 to 43 with an average of 39; the plastic limit of the Clay sublayer ranged from 14 to 23 with an average of 16; and the plasticity index of the Clay sublayer ranged from 11 to 29 with an average of 23. The

USCS classification symbol of the sampled soils comprising this sublayer was CL (lean clay).

2.3.2.2.2 Sand & Clay Sublayer

The Sand & Clay sublayer was encountered at all the test boring locations except at test boring location CC17-129A that was augered directly to 14.5 feet bgs. The sublayer was approximately 1 to 8 feet thick at the test boring locations. The material typically consisted of moist, loose to medium dense, brown and dark brown, fine to medium SAND “and” to “little” Silty CLAY to SILT, “little” to “no” fine gravel OR moist, brown, stiff, CLAY & SILT, “and” to “little” amounts of fine to medium SAND, “little” to “no” fine gravel. SPT N-values ranged from 4 bl/ft to 17 bl/ft with an average value of 9 bl/ft at the test boring locations.

Pocket penetrometer readings of samples collected in the Sand & Clay sublayer ranged from 1.0 tsf to greater than 4.5 tsf with an average of 3.75 tsf.

Based on samples tested as part of this program, the liquid limit of the Sand & Clay sublayer ranged from no value (NV) to 27 with an average of 24; the plastic limit of the Sand & Clay sublayer ranged from non-plastic (NP) to 14 with an average of 13; and the plasticity index of the Sand & Clay sublayer ranged from NP to 14 with an average of 11. The USCS classification symbol of the sampled soils comprising this sublayer was CL (lean clay), SC (clayey sand) and SM (silty sand).

2.3.2.3 Sand & Gravel

The Sand & Gravel layer was encountered at all test boring locations except at test boring location

CC17-121. The layer was approximately 1.5 to 5.0 feet thick at the test boring locations where the layer was fully penetrated. The material typically consisted of moist to wet, medium dense to very dense, brown and gray, fine to coarse SAND “and” to “trace” fine to coarse gravel, “little” to “trace” clay

& silt to silt OR medium dense to very dense, gray fine to coarse GRAVEL and fine to coarse SAND, “little” to “trace” clay & silt to silt. SPT N-values ranged from 10 bl/ft to greater than 50 bl/ft with an average value of 28 bl/ft at the test boring locations.

2.3.2.4 Weathered Rock

The Weathered Rock layer was encountered at all test boring locations except at test borings CC17-

122 and CC17-129. The layer was approximately 0.3 to 2.0 feet thick at the test boring locations. The material typically consisted of wet, very dense, light gray and gray, fine to coarse SAND, “and” to

“little” fine to coarse gravel, “little” to “trace” silt (weathered limestone) or completely weathered limestone. SPT N-values were greater than 50 bl/ft for each split spoon sample conducted within this layer at the test boring locations.

2-10

2.3.2.5 Bedrock

The Bedrock layer was penetrated at all test boring locations except at test boring location CC17-129 where the test boring was terminated above the top of bedrock. The Bedrock typically consisted of medium to moderately hard, slightly weathered to moderately weathered, light gray LIMESTONE with interbedded shale seams ranging 1/2-inch to 3-inch thick, spacing ranging from 1 inch to 12 inches.

The limestone occasionally contained thicker layers of very soft to soft, moderately weathered to completely weathered, dark gray SHALE, which are typically concentrated along the southern end of the alignment.

The recovery values for the rock cores ranged from 61% to 100% with an average of 93%, excluding rock core run 2B from test boring location CC17-127 where a portion of the core fell into the borehole and could not be recovered. The RQD values for the rock cores ranged from 33% to 100% with an average of 82%.

2.4 Groundwater Conditions

The depth to groundwater was recorded prior to backfilling at each test boring location. Depth to groundwater was measured between approximately 6 and 18.5 feet bgs (i.e., between El. 519.5 and

513.3). The groundwater level was typically recorded within the hollow stem auger at the test boring locations and may not represent static groundwater conditions. No groundwater monitoring wells were installed as part of this test boring program.

Table 2-3 presents the measured groundwater elevation in each test boring where the groundwater level was encountered.

2.5 Expected Variations in Subsurface Conditions

The general subsurface conditions presented herein are based on soil, rock and groundwater conditions observed at the test boring locations. However, subsurface conditions may vary between test boring locations. If conditions are found to be different from those described herein, data contained in this report should be reevaluated by CDM-Stanley and confirmed in writing.

Water levels measured in the test borings should not necessarily be considered to represent stabilized groundwater levels. In addition, water levels are expected to fluctuate with river level, season, temperature, climate, construction in the area and other factors. Actual conditions during construction may be different from those observed at the time of this exploration program.

Appendix A

Geophysical Exploration Report

Geoscience Geophysics Forensics Consulting

212 N. Main PO Box 46 Muenster, TX 76252 940-759-2915 Fax: 940-759-2916 www.gehriginc.com TBPE Firm Reg. #F-10736 TBPG Firm Reg. #50305

Geophysical Exploration Report at the

Bypass Channel – North Segment

Fort Worth Central City

April 11, 2018

Prepared for:

Prepared by:

Michael D. Gehrig, P.G., P.E.

President

The engineering and geoscientist seals appearing on this document were authorized by Michael D. Gehrig, P.E., P.G. #92628 and #10098 on April 11, 2018 employed by Gehrig, Inc. (TBPE Firm Reg. # F10736, TBPG Firm Reg. #50305). Record copy is on file. This document may not be changed without written permission from Michael D. Gehrig, P.G., P.E.

Michael D. Gehrig Geophysics

10098

A-1

Project No. 17-08-001 Page 2

REPORT INDEX

A. INTRODUCTION……………………………………………………

B. DOCUMENTATION REVIEW…………………………………………….. 4

C. NEAR SURFACE GEOPHYSICAL EXPLORATION TECHNIQUES… 4

D. GEOELECTRICAL SURVEYING……………..………………………

E. SEISMIC EXPLORATION METHODS………………………………

F. INTERPRETATON OF GEOPHYSICAL RESULTS…………………… 9

G. REFERENCES…………………………………………………………….. 12

H. LIMITATIONS……………………………………………………………….. 13

APPENDIX A – GEOPHYSICAL DATA

Figure 1 – Overall Layout Figure 2 – ERT/SRT Plan & Profile View, Centerline Offset & Hardedge North Figure 3 – ERT/SRT Plan & Profile View, Centerline South (13+31 to 30+50) Figure 4 – ERT/SRT Plan & Profile View, Centerline South (30+50 to End) & Mid Perpendicular Figure 5 – ERT/SRT Plan & Profile View, Hardedge South (213+35 to 231+50) Figure 6 – ERT/SRT Plan & Profile View, Hardedge South (231+50 to End) & South Perpendicular Figure 7 – ERT/SRT Plan & Profile View, North Perpendicular Figure 8 – SRT P-wave Velocities, Centerline Offset & Hardedge North Figure 9 – SRT P-wave Velocities, Centerline South (13+31 to 30+50) Figure 10 – SRT P-wave Velocities, Centerline South (30+50 to End) & Mid Perpendicular Figure 11 – SRT P-wave Velocities, Hardedge South (213+35 to 231+50) Figure 12 – SRT P-wave Velocities, Hardedge South (231+50 to End) & South Perpendicular Figure 13 – SRT P-wave Velocities, North Perpendicular Figure 14 – Top of Rock Surface Interpretation Figure 15 – Geophysical Summary Sheet

A-2

Project No. 17-08-001 Page 3

Bypass Channel – North Segment Fort Worth Central City

A. INTRODUCTION

Gehrig, Inc. was retained by CDM Federal Program Corporation (CDM Smith) to conduct a geophysical exploration survey at the proposed Bypass Channel – North Segment in Fort Worth under the service order number 1402-007-004-GP. The proposed north bypass channel is approximately 3,500 feet long and will intersect the West Fork Trinity River. It includes the construction of a levee embankment on the western side of the channel and a retaining wall on the eastern side. The North Bypass Channel is part of the greater Panther Island Project whose purpose is to provide flood protection under the federal project participation.

CDM Smith requested two (2) 2-D exploratory geophysical methods, specifically electrical resistivity tomography (ERT) and seismic refraction tomography (SRT) to provide a more detailed understanding of subsurface conditions. The primary objectives of the geophysical study are as follows:

Review existing geotechnical data provided by CDM Smith near the geophysical investigation to “ground truth” the geophysical results and interpretation;

Profile the top of rock including a surface contour map of the approximate top of rock incorporating all relevant geotechnical and geophysical information;

Develop site plan view, subsurface profiles, and tables (PPTs) of seismic refraction data along the proposed alignments presenting lithostratigraphic data including station number, ground surface elevations, P-wave velocity in 10-ft elevation intervals, approximate top of rock, and groundwater surface elevation. Groundwater elevations will be based on the Phase 3 geotechnical investigation conducted by CDM Smith;

Develop plan and profile (PPs) views of electrical resistivity tomography (ERT) along the test line alignments with lithostratigraphic interpretation;

and

Develop a digital report.

The approximate top of weathered rock was also proposed in the service order.

Due to thin weathered rock thicknesses (< 2.5 feet) based on the most recent, CC- 17 geotechnical boring series, weathered rock is difficult to differentiate from competent rock using geophysical methods.

Three field personnel from Gehrig, Inc. conducted the geophysical field investigation between September 28, 2017 and October 11, 2017. The south perpendicular line was the original test line conducted on March 8, 2017.

This is the start of the file's text. The full file is on GovTribe.

File details come from the government source that posted it. Updated Mar 7, 2024.