Texas Department of Criminal Justice

Bryan Collier Executive Director

ADDENDUM A-001 SOLICITATION NO. 696-FD-17-B013 REPLACE GAS AND WATER LINES SCOTT UNIT

MARCH 15, 2017

TO ALL PLAN HOLDERS: 3/15/2017 The comments listed below revise and modify the Contract Documents.

Acknowledgment of receipt of this addendum should be indicated on Page 2 of the Contract Documents; Solicitation, Offer and Award, Block 18 or by enclosing a copy of the Addendum/Amendment.

CONTRACT DOCUMENTS

Contract Documents, page 13 Replace Section H.3.B “http://www.tdcj.state.tx.us/vacancy/hr-policy/index/htm” Special Security Measures with “http://www.tdcj.texas.gov/divisions/hr/hr-policy/index.html”

Contract Documents, page 26-27 Replace code reference in the paragraph with “in accordance Section I.2.5.1 with Texas Government Code, Sections 2161.181-182, Historically Underutilized Businesses 2161.252(b), and Texas Administrative Code, Title 34, Part 1, Chapter 20, Subchapter D, Division 1, Rule 20.285. Pursuant to the Texas Statewide Support Services Division HUB Rules, Texas Administrative Code, Title 34, Part 1, Chapter 20, Subchapter D, Division 1, Rule 20.285,”.

Contract Documents, page 79 Replace code reference in the first sentence with “TAC, Title Section K.4, Preference Claim 34, Part 1, Chapter 20, Subchapter D, Division 2, Rule 20.306,”.

Contract Documents, page 82 Replace “www.sao.state.tx.us” with “www.sao.texas.gov”. Section K.18, Fraud, Waste or Abuse

Contract Documents, page 90 Replace code reference in the paragraph with “Texas Section M.1.1.2 Administrative Code, Title 34, Part 1, Chapter 20, Evaluation Factors For Awards Subchapter C, Division 2, Rule 20.206,”.

Our mission is to provide public safety, promote positive change in offender behavior, reintegrate offenders into society, and assist victims of crime.

P.O. Box 99 Huntsville, Texas 77342-0099 (936) 437-7015 www.tdcj.texas.gov ATTACHMENTS

Pre-bid Conference Meeting Minutes Two (2) pages Pre-bid Conference Sign In Sheet One (1) page Questions and Answers Two (2) pages Reference: Geotechnical Report 1 Fifty-four (54) pages Reference: Geotechnical Report 2 Forty-five (45) pages

CLARIFICATION

Geotechnical Reports: A geotechnical report was not undertaken for this project. The two attached geotechnical reports were for different projects at Scott Unit. The reports are provided as reference data for the soils in the area for the Bidders.

End of Addendum A-001

Our mission is to provide public safety, promote positive change in offender behavior, reintegrate offenders into society, and assist victims of crime.

P.O. Box 99 Huntsville, Texas 77342-0099 (936) 437-7015 www.tdcj.texas.gov TEXAS DEPARTMENT OF CRIMINAL JUSTICE FACILITIES DIVISION GAS AND WATERLINE REPLACEMENT WAYNE SCOTT UNIT, ANGLETON, TX SOLICITATION NO. 696-FD-17-B013

PRE-BID CONFERENCE MINUTES February 28, 2017

Date and Location of Meeting : February 28, 2017 – 10:00 a.m. Trusty Meeting Room, Wayne Scott Unit, 6999 Retrieve Road, Angleton, Texas

Introduction:

Lynne Piippo, TDCJ Contract Administrator, presented the Agenda and the handouts. She then introduced the speakers.

HUB Program:

Ruby Cowan, TDCJ HUB Coordinator, explained how to prepare the HUB Subcontracting Plan (HSP) in details. The handout of HUB Subcontracting Plan (HSP) was distributed in the meeting.

Security:

Major Marshall, TDCJ Warden Staff, discussed security considerations. A prison representative will accompany the construction crew at all times. Construction equipment will be checked in and out each day. Workers will be vetted (background checks) and approved by TDCJ.

Contractors need to complete all documents correctly. Make sure workers complete the Background Questionnaire and list all offenses on Question #17. Failure to list any criminal charges is considered falsification and worker will be disqualified for one year. Contractor shall become familiar with front end document. There are some administrative requirements we require during construction phase and will be discussed during pre- construction meeting.

Introduction of Design / Project Overview:

Brian Carney, TDCJ Facilities Engineer, introduced himself as Project Management representative from TDCJ Engineering.

Monica Stiggins and Kenyon Hunt, RPS Klotz Associates Engineers, discussed the project scope in detail. Gas line work includes replacement of approximately 25,000 linear feet of gas distribution lines (1-inch – 4-inch in diameter). Gas line work also includes replacing gas service connections at residences including gas meters, steel piping and isolation valves.

Water line work includes replacement of approximately 30,000 linear feet of water distribution lines ranging in size from 1-inch to 12-inch in diameter. The work also includes replacing service connections at residences including galvanized steel piping, hose bibs and isolation valves at residences. The existing gas and water pipe will be abandoned in place, unless the pipe conflicts with proposed construction work.

Scheduling:

Jesse Waltz, TDCJ Project Scheduler, stated Primavera P6 Scheduling software is required by TDCJ for this project. Recommend hiring a scheduler for this job instead of purchasing this software due to the cost, and also because it would not be possible to become a qualified user of this software before the 14 day deadline for the baseline submission. Reminded paying attention to the contractor scheduling requirements. The handout of Scheduling Requirements was distributed in the meeting.

Quality Control:

Lynne Piippo, TDCJ Contract Administrator, stated quality control is the Contractor’s responsibility. The handout of Quality Control was distributed in the meeting.

Contracts:

Lynne Piippo, TDCJ Contract Administrator, explained construction bid deposit, construction period, standard work week, liquidated damages for construction delay, due date for clarifications and substitution requests, etc. Piippo also stated that all substitution request and questions must be submitted, in writing for consideration. No verbal agreements are binding.

• Notice to Proceed will be issued on or after September 1, 2017 (Fiscal Year 2018 for TDCJ). • Bid Opening is in Huntsville on May 2 nd , 2017 at 2 pm. • Bid Bond must be active for 120 days. • Liquidated damages are set at $475/day. • Contract time is 558 calendar days. Site Tour:

The group toured the site, visiting the water plant, the residences and the gas facilities. The group also observed where pipelines will be installed underneath Oyster Creek.

Reconvene For Questions:

Lynne Piippo, TDCJ Contract Administrator, stated if the contractors have any questions, put them in writing and TDCJ will respond to them by issuing an addendum if appropriate. All bidder’s questions are due by close-of- business on April 14, 2017.

Adjourn:

The meeting was declared over and adjourned at noon, approximately 12:00 p.m.

The contract language shall prevail should anything contained in these minutes contradict the contract terms. The essence of a prison unit is security, therefore security related issues are fluid and subject to change. 696-FD-17-B013 Replace Gas and Water Lines Scott Unit Pre-Bid Conference February 28, 2017

Name Company Telephone Fax E-Mail (please print) Lynne Piippo TDCJ Contracts (936) 437-7114 (325) 223-0310 [email protected]

Warden D. Muniz TDCJ Scott Unit (979) 849-9306 (979) 848-5137 [email protected]

Asst. Warden R. Waldron TDCJ Scott Unit (979) 849-9306 (979) 848-5137 [email protected]

Major R. Marshall TDCJ Scott Unit (979) 849-9306 (979) 848-5137 [email protected]

Ruby Cowan TDCJ HUB Program (936) 437-3128 (936) 437-7088 [email protected]

Brian Carney TDCJ Engineering (936) 437-7221 (325) 223-0294 [email protected]

Jesse Waltz TDCJ Scheduling (936) 437-7254 [email protected]

Dan Dirba TDCJ Facilities (361) 362-6620 [email protected]

Monica Stiggins Klotz Associates (281) 589-7257 (281) 589-7309 [email protected]

Robert Buchanan III TDCJ Facilities (936) 437-7265 [email protected]

Russell Cooper S.J. Louis Construction (832) 767-4964 (832) 767-4681 [email protected]

Toby Wedgman MP Nexlevel (281) 477-6662 (281) 477-6882 [email protected]

Scott Hunter Huff & Mitchell (281) 304-9100 (281) 304-9107 [email protected]

Jackie Lillie TDCJ Scott Unit (936) 577-9513 (979) 849-9308 [email protected]

Larry Kile TDCJ Scott Unit (361) 318-1112 [email protected]

Kenyon Hunt Klotz Associates (281) 589-7257 (281) 589-7309 [email protected]

TDCJ Scott Unit Replace Gas and Water Lines Solicitation # 696-FD-17-B013, MWR # 01910013

Questions and Answers

Question 1: Are there any portions of the project that will need to be Bored?

Answer 1: See Sheets 7-24 of the Drawings for boring lengths and locations. 3/9/2017

Question 2. Are the crossing to be Jack & Bored or Directionally Bored?

Answer 2: Trenchless construction method is specified in Section 31 71 19.

Question 3. What are the approximate length and diameter of the portions to be bored?

Answer 3: There are numerous pipe installations using trenchless construction methods; see Sheets 7-24. Approximately 1,000 feet of waterline (4”-12” in diameter) will be installed using trenchless methods. Approximately 450 feet of gas line (2”-4” in diameter) will be installed using trenchless methods.

Question 4. Do you have a list of materials and pipe footages for this project that we can reference from?

Answer 4: The Specification Book and Drawings show the necessary materials. Approximately 31,500 feet of waterline (2”-12” in diameter) will be installed using open cut and trenchless methods. Approximately 26,000 feet of gas line (2”-4” in diameter) will be installed using open cut and trenchless methods.

Question 5. I can see on the plans for water service size but not for gas. Do you want to run a 2” service line up to the building from a 2” or 4” main?

Answer 5:

On Sheet 29 Detail 6, the residential gas line connection is 1-inch. For most of the facility connections, the incoming line is the connection size (usually 2”). See photos below.

Photo 1: The gas connection to the main facility. Photo 2: The second photo is of the above ground connection in the SW corner of the main facility. Photo 3: The third photo is of the above ground gas connection directly west of the main prison.

1 of 2

Figure 1: Connection to Main Prison

Figure 2: Gas connection in SW corner outside Main Prison

Figure 3: Gas connection situated to the west of the main prison.

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GEOTECHNICAL INVESTIGATION TEXAS DEPARTMENT OF CRIMINAL JUSTICE (TDCJ) SCOTT UNIT – OYSTER CREEK SEWER FORCE MAIN CROSSING ANGLETON, TEXAS

REPORT NO. 1140214201

Reported to:

RPS/KLOTZ ASSOCIATES

Houston, Texas

Submitted by:

GEOTEST ENGINEERING, INC.

Houston, Texas

Key Map No. 857 N

TABLE OF CONTENTS

Page SUMMARY ...... 1 1.0 INTRODUCTION 1.1 Project Description ...... 3 1.2 Geotechnical Investigation Program ...... 3 2.0 FIELD INVESTIGATION ...... 4 2.1 General ...... 4 2.2 Sampling Methods ...... 4 3.0 LABORATORY TESTING ...... 6 4.0 SITE CHARACTERIZATION 4.1 Site Geology ...... 7 4.2 Soil Stratigraphy ...... 7 4.3 Groundwater ...... 8 5.0 GEOTECHNICAL RECOMMENDATIONS 5.1 General ...... 9 5.2 Open-Cut Excavation ...... 9 5.2.1 Geotechnical Parameters ...... 9 5.2.2 Excavation Stability ...... 9 5.2.3 Insertion/Reception Pits for Directional Drilling ...... 11 5.2.4 Groundwater Control ...... 11 5.2.5 Insertion/Receiving Pit Backfill ...... 12 5.3 5.3.1 Geotechnical Parameters ...... 12 5.3.2 Earth Pressure on Pipe and Casing Augering ...... 12 5.3.3 Carrier Pipe Design Parameters...... 12 5.3.4 Influence of Directional Drilling on Adjacent Structures ...... 13 5.4 Structures ...... 13 5.4.1 Description ...... 13 5.4.2 Foundation Conditions ...... 14

TABLE OF CONTENTS (cont'd)

Page 5.4.3 Foundation Design Recommendations ...... 14 5.4.4 Protection of Below Grade Structures ...... 15 5.4.5 Groundwater Control During Construction ...... 15 5.4.6 Structure Backfill ...... 15 6.0 PROVISIONS ...... 16

ILLUSTRATIONS Figure Vicinity Map ...... 1 Plan of Borings ...... 2 Boring Log Profile ...... 3 Symbols and Abbreviations Used on Boring Log Profile ...... 4 Trench Support Earth Pressure ...... 5.1 and 5.2 Stability of Bottom for Braced Cut ...... 6 Earth Pressure on Pipe Directional Drilling ...... 7 Lateral Earth Pressure Diagram for Permanent Wall ...... 8.1 and 8.2 Uplift Pressure and Resistance ...... 9

TABLES Table Summary of Boring Information ...... 1 Geotechnical Design Parameter Summary: Open-cut Excavation ...... 2 Geotechnical Design Parameter Summary: Trenchless Installation ...... 3

APPENDIX A

Figure Log of Borings ...... A-1 and A-2 Symbols and Terms Used on Boring Logs...... A-3

APPENDIX B

Figure Grain Size Distribution Curves ...... B-1 and B-2

Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

SUMMARY

A geotechnical investigation was conducted in connection with the design and construction of Oyster Creek Sanitary Sewer Force Main Crossing at the Texas Department of Criminal Justice (TDCJ) – Scott Unit in Angleton Texas.

This project consist of designing a portion of a 8-inch sanitary sewer force main that will be installed by directional drilling under Oyster Creek at TDCJ – Scott Unit in Brazoria County, Texas. The existing creek bottom is about 16 feet and the proposed force main is about 21 feet.

The scope of this study included, drilling and sampling a total of two (2) borings to a depth of 45 feet, performing laboratory tests on samples recovered from the borings, performing engineering analyses to develop geotechnical recommendations for the proposed sanitary sewer force main and preparing a geotechnical report.

The principal findings and conclusions developed from this investigation are summarized as follows:

The subsurface soils below the existing grade, as revealed by borings GB-1 and GB-2, consist of very soft to stiff brown clay and silty clay to depths of 6 to 16 feet. The silty clay and clay soils are underlain by very loose to compact, gray and brown fine sand with silt and silty sand to a depth of 45 feet, the termination depth of borings. In boring GB-1, a layer of gray clay with sand seams was encountered between the depths of 23 and 25 feet.

Free water was encountered during drilling at depths ranging from 7 feet to 16 feet. The water level measured 15 minutes after the free water was first encountered was at depths ranging from 3 feet to 7 feet.

1 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

An allowable (net) bearing pressure of 1,000 psf may be used for the design of air release valve encased in fiberglass manholes placed at a depth of 6 to 8 feet (into soft to stiff clay and silty clay and loose silty sand).

2 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

1.0 INTRODUCTION

1.1 Project Description

This project consist of designing a portion of an 8-inch sanitary sewer force main that will be installed by directional drilling under Oyster Creek at TDCJ – Scott Unit in Brazoria County, Texas. The existing creek bottom is about 16 feet and the proposed force main is about 21 feet.

1.2 Geotechnical Investigation Program

The purposes of this investigation were to explore the subsurface conditions and to develop geotechnical recommendations pertinent to the design and construction of proposed 8-inch sanitary sewer force main crossing at Oyster Creek. The scope of this investigation was consisted of the following tasks.

Drilled and sampled two (2) borings each to a depth of 45 feet.

Performed laboratory tests, on selected representative soil samples, to determine the engineering properties of the soils and to select design soil parameters.

Performed engineering analyses to develop geotechnical recommendations for the design and construction of the proposed 8-inch sanitary sewer force main crossing at oyster creek

Prepared a geotechnical report.

3 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

2.0 FIELD INVESTIGATION

2.1 General

Subsurface conditions were explored by drilling a total of two (2) borings each to a depth of 45 feet. All borings were drilled with a buggy-mounted rotary drill rig. The approximate boring locations are shown on Plan of Borings, presented on Figure 2. The survey information, (Station Numbers, Offset and ground surface elevations) for the borings drilled was provided to us by RPS/Klotz Associates, Inc.

2.2 Sampling Methods

At each boring location soil samples were obtained at 5-ft intervals in granular soils, and continuously in cohesive soils between the TxDOT Cone Penetrometer Tests. TxDOT Cone Penetrometer Tests (Tex-132-E) were performed at approximate 5-foot intervals throughout the depth of each boring. Results of the tests are recorded on the boring logs as the number of blows for the first and second 6 inches of penetration at the respective test depths. Samples of cohesive soils were obtained with a 3-inch diameter thin-walled tube sampler in general accordance with ASTM Method D 1587. Each sample was removed from the sampler in the field by our soils technician, carefully examined, and classified according to the Unified Soil Classification System (USCS). Suitable portions of each sample were wrapped and sealed in the field and transported to Geotest's laboratory. The shear strength of cohesive soil samples was estimated in the field using a calibrated hand pocket penetrometer.

Detail descriptions of the soils encountered, together with recorded blow counts from TxDOT Cone Penetrometer Tests, are provided on the boring logs presented on Figures A-1 and A-2 in Appendix A. A key to symbols and terms used on the boring logs is given on Figure A-3 in Appendix A. The consistency (strength description) of cohesive soils is based on test data from

4 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas triaxial compression test (TAT) and TxDOT cone penetrometer data, where TAT data is not available.

Measurements of the depth to water were taken in the open boreholes during drilling. The results of these observations are noted at the bottom of the boring logs.

After taking final measurements of the depth to groundwater at each boring location, each of the open boreholes, were grouted with cement-bentonite grout.

5 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

3.0 LABORATORY TESTING

A laboratory test program was developed to measure pertinent physical and strength characteristics of representative samples from the field exploration. Classification tests were performed on selected samples to aid in soil classification. All geotechnical tests were performed in accordance with TxDOT procedures and ASTM procedures where TxDOT procedures are not available.

Undrained shear strengths of selected cohesive soil samples were measured by unconfined compression (ASTM D 2166) and unconsolidated-undrained (UU) triaxial compression (Tex-118-E) tests. Shear strengths of cohesive samples were also estimated in the field using a calibrated hand pocket penetrometer, and in the laboratory with a Torvane.

Moisture content and dry unit weight were measured for each unconfined compression and U-U triaxial compression test sample. Moisture content measurements (Tex-103-E) were also conducted on most samples to identify the moisture profile at each boring location. Liquid and plastic limit tests (Tex-104-E, Tex-105-E) were performed on selected cohesive samples to measure soil plasticity characteristics and to aid in soil classification.

Results of most laboratory tests are tabulated on the boring logs presented on Figures A-1 and A-2 in Appendix A.

6 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

4.0 SITE CHARACTERIZATION

4.1 Site Geology

The project area lies in the Beaumont Formation. The clays and sands of the Beaumont Formation are over-consolidated as a result of desiccation from frequent rising and lowering of the sea level and the groundwater table. Consequently, clays of this formation have moderate to high shear strength and relatively low compressibility. The sands of the Beaumont Formation are typically very fine and often silty. Further, there is occasional evidence in the Houston area of the occurrence of cemented material (sandstone and siltstone) deposits within the Beaumont Formation.

4.2 Soil Stratigraphy

The subsurface soils below the existing grade, as revealed by borings GB-1 and GB-2, and as shown in boring log profile presented on Figure 3 consist of very soft to stiff brown clay and silty clay to depths of 6 to 16 feet. The silty clay and clay soils are underlain by very loose to compact, gray and brown fine sand with silt and silty sand to a depth of 45 feet, the termination depth of borings. In boring GB-1, a layer of gray clay with sand seams was encountered between the depths of 23 and 25 feet.

The clay is of high to very high plasticity with liquid limits ranging from 63 to 71 and plasticity indices ranging from 39 to 44. The silty clay is of medium to high plasticity with liquid limits ranging from 39 to 40 and the plasticity indices ranging from 17 to 19. The fines content (percent passing No. 200 sieve) clay and silty clay ranges from 92 to 98 percent. The fines content of silty sand ranges from 34 to 45 percent. The percent fines of fine sand with silt ranges from 7 to 11 percent.

7 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

4.3 Groundwater

Free water was encountered during drilling at depths ranging from 7 feet to 16 feet. The water level measured 15 minutes after the free water was first encountered at depths ranging from 3 feet to 7 feet.

It should be noted that various environmental and man-made factors such as amount of precipitation, could substantially influence groundwater level.

8 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

5.0 GEOTECHNICAL RECOMMENDATIONS

5.1 General

5.2 Open-Cut Excavation

5.2.1 Geotechnical Parameters. Based on the soil conditions revealed by the borings, geotechnical parameters were developed for the open cut excavation for the insertion/reception pits. The geotechnical design parameters are provided in Table 2. For design, the groundwater level should be assumed to exist at the ground surface, since this condition may exist after a heavy rain or flooding.

5.2.2 Excavation Stability. The open excavation may be shored, laid back to a stable slope or some other equivalent means used to provide safety for workers and adjacent structures. The excavating and trenching operations should be in accordance with OSHA Standards, OSHA 2207, Subpart P, latest revision and the City of Pasadena requirements.

Excavation Shallower Than 5 Feet – Excavations that are less than 5 feet (critical height) deep should be appropriately protected when any indication of hazardous ground movement is anticipated.

Excavation Deeper Than 5 Feet - Excavations that are deeper than 5 feet should be sloped, shored, sheeted, braced or laid back to a stable slope or supported by some other equivalent means or protection such that workers are not exposed to moving ground or

9 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

cave-ins. The slopes and shoring should be in accordance with the trench safety requirements per OSHA Standards. The following items provide design criteria for trench stability.

(i) OSHA's Soil Type. Based on the soil conditions revealed by the borings and the assumed groundwater level at surface, OSHA's soil type "C" should be used for the determination of allowable maximum slope and/or the design of a shoring system. For shoring deeper than 20 feet, an engineering evaluation is required.

(ii) Excavation Support Earth Pressure. Based on the subsurface conditions indicated by this investigation and laboratory testing results, the excavation support earth pressure diagrams were developed and are presented on Figures 5.1 and 5.2. The pressure diagrams can be used for the design of temporary excavation bracing. For a trench box, a lateral earth pressure resulting from an equivalent fluid with a unit weight of 81 pcf is recommended. The above value of equivalent fluid pressure is based upon an assumption that the groundwater level is near the ground surface, since these conditions may exist after a heavy rain or flooding. Effect of surcharge loads at the ground surface should be added to the computed lateral earth pressure. A surcharge load, q, will typically result in a lateral load equal to 0.5 q.

(iii) Bottom Stability. In braced cuts, if tight sheeting is terminated at the base of the cut, the bottom of the excavation can become unstable under certain conditions. This condition is governed by the shear strength of the soils and by the differential hydrostatic head between the groundwater level within the retained soils and the groundwater level at the interior of the trench excavation. For cuts in cohesive soils, as encountered in the borings GB-1 up to 6 feet and GB-2 up to 16 feet, for the excavation depths of 6 to 8 feet, the stability of the bottom can be evaluated in accordance with the procedure outlined on Figure 6.

10 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

However, due to the silty sand encountered below 6 feet in boring GB-1, the excavation in this area must be done after dewatering to avoid bottom stability problems.

5.2.3 Insertion/Reception Pits for Directional Drilling. The Insertion/Reception pits proposed for the trenchless method should be constructed per City of Houston Standard Specifications, Section 02400 (tunnel shafts). The access shaft may be constructed by retained excavations or can be installed by sunken caisson. These methods are described below:

Retained Excavation. Retained excavations generally require less ground surface area than open-cut excavation with laid back slopes. The retention system can consist of driven sheetpile, liner plates, solider pile/lagging, driven planking, or ring beams and timber lagging. The items pertaining to design criteria for retained excavation stability should be in accordance with guidelines as outlined in section 5.2.2.

Sunken Caisson Installation. The caisson procedure eliminates the need for a temporary retention system. Caisson units can, however, experience problems with alignment and termination at the proper design depth. Stability considerations of the excavation bottom are similar to those for retained excavation techniques.

5.2.4 Groundwater Control. Excavations for the proposed insertion/reception pits may encounter groundwater seepage to varying degrees depending upon groundwater conditions at the time of construction and the location and depth of excavation. In cohesive soils, as encountered in GB-1 up to 6 feet in boring GB-2 up to 16 feet, for the excavation depths of 6 feet to 8 feet, groundwater may be managed by collection in trench bottom sumps for pumped disposal.

However, in cohesionless soil, as encountered below 6 feet in boring GB-1, dewatering such as will be required to lower the groundwater level to at least 5 feet below the level of excavation.

11 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

The well points should be pumping well ahead of the time excavation starts so that a steady state condition (at least 5 feet below the proposed excavation bottom) is achieved.

It is recommended that the groundwater conditions be verified at the time of construction.

5.2.5 Insertion/Receiving Pit Backfill. The excavated insertion/reception pits should be backfilled per the Item 400 "Excavation and Backfill for Structures”.

5.3 Trenchless Installation

It is understood that the proposed 8-inch diameter sanitary sewer force main will be installed by directional drilling method of construction.

5.3.1 Geotechnical Parameters. Based on the soil conditions revealed by soil borings, laboratory test data, geotechnical design parameters were developed for cohesive soils and cohesionless soils and are provided in Tables 2 and 3. The cohesive soils include lean clays and cohesionless soils include silty sand. For design conditions, the groundwater levels should be assumed to exist at the ground surface.

5.3.2 Earth Pressure on Pipe Directional Drilling. The earth pressures on pipe for directional drilling should be determined from Figure 7. Equations to calculate the directional drilling casing loads are also shown on Figure 7.

5.3.3 Carrier Pipe Design Parameters. Carrier pipe must be sufficiently strong to withstand anticipated long-term ground loads and must not be subjected to deterioration by substance either in ground or in the directional drilling. The carrier pipe design should include consideration of not only the loads applied to the pipe but also factors other than soil loading. These factors could include minimum structural code requirements, loading from pipe jacking operations and other construction loads. The drained geotechnical design parameters given in Table 3 should be used to analyzing the soil structure intersection of the carrier pipe.

12 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

5.3.4 Influence of Directional Drilling on Adjacent Structures. Surface and near-surface structures near the pipe and casing directional drilling consist primarily of existing creek and utilities (if any).

Ground movement, in terms of loss of ground or ground lost, is commonly associated with soft ground tunneling. If such ground movement is excessive, it may cause damage to the structures and services located above the directional drilling. While ground movement cannot be eliminated, it can be controlled within certain limits by the use of proper construction techniques and good quality workmanship. These include, but are not limited to, prevention of excessive ground loss during drilling with the use of grouting and filling the annular space between the pipe or casing and the surrounding soil and prevention of undue loss of fines through dewatering.

The selection and execution of directional drilling methods that are best suited to anticipated ground conditions along the proposed trenchless installation are, in fact, the contractor's primary contribution to successful completion of the proposed trenchless installation. On review of the boring logs, the ground conditions for trenchless installation (excavation face) will be primarily through clay and silty sand layers. The ground may be expected to behave as firm to raveling ground with possible cohesive running to flowing ground near the invert (without dewatering) or raveling to running ground near the invert (with dewatering).However due to available limited boring data, soil conditions other than those encountered in borings could exist.

In general, it is the contractor's responsibility to investigate the presence of any existing utilities and other possible third party interactions along the proposed sanitary sewer force main and to accommodate all of these interactions with the use of good construction methods.

5.4 Structures

5.4.1 Description. The structures associated with this project are two air release valve encased in fiberglass manholes.

13 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

5.4.2 Foundation Conditions. Foundation conditions were explored by borings GB-1 and GB-2. Based on the soil conditions revealed by the borings, the manhole bases will be in soft to stiff clay and silty clay and very loose to compact silty sand.

5.4.3 Foundation Design Recommendations. The following items provide recommendations and design criteria for construction of the fiberglass manholes.

Allowable Bearing Pressures. An allowable (net) bearing pressure of 1,000 psf may be used for the design of fiberglass manholes placed at a depth of 6 to 8 feet (into soft to stiff clay and silty clay and loose silty sand).

Bottom Stability. The bottom stability should be followed as out lined in Section 5.2.2 of this report.

Lateral Earth Pressure. The pressure diagrams presented on Figures 5.1 and 5.2 can be used for the design of braced excavation. The lateral earth pressure diagrams presented on Figures 8.1 and 8.2 are applicable for the design of the permanent walls.

Hydrostatic Uplift Resistance. Structures extending below the groundwater level should be designed to resist uplift pressure resulting from excess piezometric head. Design uplift pressures should be computed based on the assumption that the water table is at ground surface. To resist the hydrostatic uplift at the bottom of the structure, one of the following sources of resistance can be utilized in each of the designs.

a. Dead weight of structure, b. Weight of soil above base extensions plus weight of structure, or c. Soil-wall friction plus dead weight of structure.

14 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

The uplift force and resistance to uplift should be computed as detailed on Figure 9. In determining the configuration and dimensions of the structure using one of the approaches presented on Figure 9, the following factors of safety are recommended.

a. Dead weight of concrete structure, Sf1 = 1.10,

b. Weight of soil (backfill) above base extension, Sf2 = 1.5, and

c. Soil-wall friction, Sf3 = 3.0. Friction resistance should be discounted for the upper 5 feet, since this zone is affected by seasonal moisture changes.

5.4.4 Protection of Below Grade Structures. The design of the proper means for protection of below grade structures will depend upon the potential of the aggressivity or corrosivity of soil and groundwater properties. The aggressivity testing was not within the scope of this study. The design of the protection of below grade structures is beyond the scope of services for this study.

5.4.5 Groundwater Control During Construction. The ground water control should be per guidelines as outlined in Section 5.2.3 of this report.

5.4.6 Structure Backfill. The bedding and backfill for fiberglass manholes should follow the TxDOT Houston District “Excavation and Backfill Diagrams.”

15 Geotest Engineering, Inc. Report No. 1140214201 TDCJ Scott Unit – Oyster Creek Sewer Force Main Crossing June 8, 2016 Angleton, Texas

6.0 PROVISIONS

The description of subsurface conditions and the design information contained in this report are based on the test borings made at the time of drilling at specific locations. Some variation in soil conditions may however, occur between test borings. Should any subsurface conditions other than those described in our boring logs be encountered, Geotest should be immediately notified so that further investigation and supplemental recommendations can be provided.

The depth of the groundwater level may vary with changes in environmental conditions such as frequency and magnitude of rainfall. The stratification lines on the log of borings represent the approximate boundaries between soil types. Transitions between soil types may be more gradual than depicted.

This report has been prepared for the exclusive use of Klotz Associates, Inc. and the Texas Department of Criminal Justice for the Scott Unit – Oyster Creek Sewer Force Main Crossing project, in Angleton, Texas.

This report shall not be reproduced without the written permission of Geotest Engineering, Inc., RPS/Klotz Associates, or TDCJ.

ILLUSTRATIONS Figure

Vicinity Map ...... 1 Plan of Borings ...... 2 Boring Log Profile ...... 3 Symbols and Abbreviations Used on Boring Log Profile ...... 4 Trench Support Earth Pressure ...... 5.1 and 5.2 Stability of Bottom for Braced Cut ...... 6 Earth Pressure on Pipe Directional Drilling ...... 7 Lateral Earth Pressure Diagram for Permanent Wall ...... 8.1 and 8.2 Uplift Pressure and Resistance ...... 9

TABLES

Table Summary of Boring Information ...... 1 Geotechnical Design Parameter Summary: Open-cut Excavation ...... 2 Geotechnical Design Parameter Summary: Trenchless Installation ...... 3

TABLE 1 SUMMARY OF BORING INFORMATION

Elevation*, Boring Station Offset ft Boring No. Depth (feet) GB-1 45 1+40 2' RT 13.8 GB-2 45 2+60 0' 9.8

TABLE 2

GEOTECHNICAL DESIGN PARAMETER SUMMARY OPEN-CUT EXCAVATION

Range Wet Submerged Undrained Internal of Unit Unit Cohesion, Friction Boring Stratigraphic Depths, Weight, Weight, γ', psf Angle, φ, Nos. Unit ft γ, pcf degree pcf GB-1 Cohesive 0-6 126 63 500 -- Cohesionless 6-23 98 36 -- 25 Cohesive 23-25 110 48 500 -- Cohesionless 25-45 100 38 -- 30

GB-2 Cohesive 0-16 125 63 1000 -- Cohesionless 16-45 102 39 -- 30

Notes:

1. Cohesive soils include clay and silty clay. 2. Cohesionless soils include silty sand and fine sand with silt

TABLE 3

GEOTECHNICAL DESIGN PARAMETER SUMMARY TRENCHLESS INSTALLATION – OYSTER CREEK SANITARY SEWER FORCE MAIN CROSSING (Based on Borings GB-1 and GB-2) PROPERTY COHESIVE SOILS (1) COHESIONLESS SOILS (2) Wet Unit Weight, γ, pcf 0-6 126 -- 6-13 125 (GB-2 only) 98 (GB-1 only) 13-16 120 (GB-2 only) 98 (GB-1 only) 16-23 -- 98 (GB-1 and GB-2) 23-25 110 (GB-1 only) 102 (GB-2 only) 25-45 -- 100 (GB-1 and GB-2) Submerged Unit Weight, γ', pcf 0-6 63 -- 6-13 63 (GB-2 only) 28 (GB-1 only) 13-16 60 (GB-2 only) 28 (GB-1 only) 16-23 -- 28 (GB-1 and GB-2) 23-25 48 (GB-1 only) 39 (GB-2 only) 25-45 -- 38 (GB-1 and GB-2) Moisture Content (%) 0-6 27 -- 6-13 28 (GB-2 only) 26 (GB-1 only) 13-16 22 (GB-2 only) 24 (GB-1 only) 16-23 -- 22 (GB-1 and GB-2) 23-25 45 (GB-1 only) 22 (GB-2 only) 25-45 -- 18 (GB-1 and GB-2) UNDRAINED PROPERTIES

Undrained Cohesion, cu, psf 4-6* 500 -- 6-13* 1000 (GB-2 only) -- 13-16* 900 (GB-2 only) -- 16-23* -- -- 23-25* 500 (GB-1 only) -- 25-27* -- -- Angle of Internal Friction, , degrees 4-6* -- -- 6-13* -- 28 (GB-1 only) 13-16* -- 28 (GB-1 only) 16-23* -- 28 (GB-1 and GB-2) 23-25* -- 30 (GB-2 only) 25-27* -- 30 (GB-1 and GB-2) Elastic Modulus, E, psf 4-6* 150,000 -- 6-13* 180,000 (GB-2 only) 126,000 (GB-1 only) 13-16* 360,000 (GB-2 only) 126,000 (GB-1 only) 16-23* -- 126,000 (GB- 1 and GB-2) 23-25* 200,000 (GB-1 only) 196,000 (GB2 only) 25-27* -- 196,000 (GB-1 and GB-2)

Coefficient of Lateral Earth pressure at Rest, Ko, 4-6* 1.2 -- 6-13* 1.2 (GB-2 only) 0.53 (GB-1 only) 13-16* 1.2 (GB-2 only) 0.53 (GB-1 only) 16-23* -- 0.5 (GB-1 and GB-2) 23-25* 1.2 (GB-1 only) 0.5 (GB-2 only) 25-27* -- 0.5 (GB-1 and GB-2) Poisson's Ratio, 0.45 0.3

TABLE 3 (cont'd)

GEOTECHNICAL DESIGN PARAMETER SUMMARY TRENCHLESS INSTALLATION – OYSTER CREEL CROSSING (Based on Borings GB-1 and GB-2)

PROPERTY COHESIVE SOILS (1) COHESIONLESS SOILS (2) DRAINED PROPERTIES Drained Cohesion, c', psf 4-6* 0 -- 6-13* 0 -- 13-16* 0 -- 16-23* 0 -- 23-25* 0 -- 25-27* 0 -- Angle of Internal Friction, ', degrees 4-6* 18 -- 6-13* 18 (GB-2 only) 28 (GB-1 only) 13-16* 20 (GB-2 only) 28 (GB-1 only) 16-23* -- 28 (GB-1 and GB-2) 23-25* 21 (GB-1 only) 30 (GB-2 only) 25-27* -- 30 (GB-1 and GB-2) Elastic Modulus, E, 4-6* 150,000 -- 6-13* 180,000 (GB-2 only) 126,000 (GB-1 only) 13-16* 216,000 (GB-2 only) 126,000 (GB-1 only) 16-23* -- 126,000 (GB- 1 and GB-2) 23-25* 200,000 (GB-1 only) 196,000 (GB2 only) 25-27* -- 196,000 (GB-1 and GB-2 Notes: 1. Cohesive soils include Fat Clay, Lean Clay and Sandy Lean Clay. 2. Cohesionless soils include Silty Sand and Silt w/sand. *Tunneling zone between depths of 4 and 27 feet (one bore diameter, but not less than 6 feet, above and below tunnel bore)

APPENDIX A

Figure Log of Borings ...... A-1 and A-2 Symbols and Terms Used on Boring Logs...... A-3

APPENDIX B

Figure Grain Size Distribution Curves ...... B-1 and B-2

FOR INFORMATION PURPOSES ONLY

GEOTECHNICAL INVESTIGATION SCOTT UNIT – REPAIR/RESURFACE ENTRANCE ROAD TEXAS DEPARTMENT OF CRIMINAL JUSTICE (TDCJ) ANGLETON, TEXAS

REPORT NO. 1140200001

Reported to:

KLOTZ ASSOCIATES

Houston, Texas

Submitted by:

GEOTEST ENGINEERING, INC.

Houston, Texas

Key Map No. 857 N & S

TABLE OF CONTENTS

Page SUMMARY ...... 1 1.0 INTRODUCTION 1.1 Project Description ...... 3 1.2 Geotechnical Investigation Program ...... 3 2.0 FIELD INVESTIGATION ...... 4 2.1 General ...... 4 2.2 Sampling Methods ...... 4 3.0 LABORATORY TESTING ...... 6 4.0 SITE CHARACTERIZATION 4.1 Site Geology ...... 8 4.2 Existing Pavement ...... 8 4.3 Soil Stratigraphy ...... 9 4.4 Groundwater ...... 9 5.0 GEOTECHNICAL RECOMMENDATIONS 5.1 General ...... 10 5.2 Open-Cut Excavation ...... 10 5.2.1 Geotechnical Parameters ...... 10 5.2.2 Excavation Stability ...... 10 5.2.3 Groundwater Control ...... 12 5.3 Structures ...... 12 5.3.1 Description ...... 12 5.3.2 Foundation Conditions ...... 12 5.3.3 Foundation Design Recommendations ...... 12 5.3.4 Protection of Below Grade Structures ...... 13 5.3.5 Groundwater Control During Construction ...... 13 5.3.6 Structure Backfill ...... 14

TABLE OF CONTENTS (cont'd)

Page 5.4 Pavement and Subgrade Design ...... 14 5.4.1 Design Parameters ...... 14 5.4.2 Recommended Pavement Section ...... 14 5.4.3 Preparation of Pavement Subgrade ...... 15 6.0 PROVISIONS ...... 16

ILLUSTRATIONS Figure Vicinity Map ...... 1 Plan of Borings ...... 2.1 and 2.2 Trench Support Earth Pressure ...... 3 Stability of Bottom for Braced Cut ...... 4 Lateral Earth Pressure Diagram for Permanent Wall ...... 5 Uplift Pressure and Resistance ...... 6

TABLES Table Summary of Boring Information ...... 1 Geotechnical Design Parameter Summary: Open-cut Excavation ...... 2

APPENDIX A

Figure Log of Borings ...... A-1 thru A-14 Symbols and Terms Used on Boring Logs...... A-15

APPENDIX B

Figure Compaction Test (Tex-114-E) Report ...... B-1 Texas Triaxial Compression Test (Tex-117-E) Results...... B-2a thru B-2c Report of HMAC Results...... B-3

Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

SUMMARY

A geotechnical investigation was conducted in connection with the design and construction of the Texas Department of Criminal Justice (TDCJ) – Scott Unit – Entrance Road Repair/Resurface in Angleton Texas.

The project consists of repair and resurfacing of approximately 9,500 linear feet of two lane asphalt entrance road to the Scott Unit of TDCJ from the north end of the employee housing southeast to the front picket adjacent to the employee parking lot in Brazoria County, Texas. It is understood that entrance roadway will be reconstructed in 2 phases (Phase I and Phase II construction). The project also includes construction of two (2) culverts with 30-inch diameter reinforced concrete pipe (RCP).

The scope of this study included, drilling and sampling a total of fourteen (14) borings to depths ranging from 5 to 15 feet, performing laboratory tests on samples recovered from the borings, performing engineering analyses to develop geotechnical recommendations for the proposed pavement and culverts construction and preparing a geotechnical report.

The principal findings and conclusions developed from this investigation are summarized as follows:

• The existing pavement as revealed by borings B-1 through B-14 consists of 1.5 to 4 inches of asphalt over 7 inches to 12 inches of base material. The base material included shell and sand mix and crushed concrete.

• The subsurface soils below the existing paving, as revealed by borings B-1 through B-14, consist of very soft to stiff dark gray, brown and gray clay and silty/sandy clay to a depth of 5 to 15 feet, the termination depth of the borings. In boring B-13, a layer of loose silt was encountered between depths of 3 and 5 feet, the explored depth of boring.

1 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

• No groundwater was encountered in all the borings drilled for this study.

• An allowable (net) bearing pressure of 2,000 psf may be used for the design of culverts structure placed at a depth of 5 feet (into stiff to very stiff clay and sandy clay). The details are given in Section 5.4 of this report.

• The recommended pavement section for the Scott Unit entrance roadway is given below.

Pavement Course Thickness, inches Asphaltic Concrete Surface 2 Black Base 5 5 to 6% Lime Stabilized Subgrade 8

Pavement Course Thickness, inches Asphaltic Concrete Surface 2 Crushed Concrete 10 5 to 6% Lime Stabilized Subgrade 8

2 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

1.0 INTRODUCTION

1.1 Project Description

1.2 Geotechnical Investigation Program

The purposes of this investigation were to explore the subsurface conditions along the proposed entrance roadway and develop geotechnical recommendations pertinent to the design and construction of proposed culverts and pavement. The scope of this investigation was consisted of the following tasks.

• Drilled and sampled fourteen (14) borings each to depths ranging from 5 to 15 feet.

• Performed laboratory tests, on selected representative soil samples, to determine the engineering properties of the soils and to select design soil parameters.

• Performed engineering analyses to develop geotechnical recommendations for the design and construction of the proposed pavement and culverts construction.

• Prepared a geotechnical report.

3 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

2.0 FIELD INVESTIGATION

2.1 General

Subsurface conditions were explored by drilling a total of fourteen (14) borings to depths ranging from 5 to 15 feet. All borings were drilled with a truck-mounted rotary drill rig. Asphalt coring was performed in the existing pavement to evaluate the existing pavement thickness and access the subsurface soils at all the boring locations. The approximate boring locations are shown on Plan of Borings, presented on Figures 2.1 and 2.2. The survey information, (station Numbers, offset and surface elevations) for the borings drilled was provided by Klotz Associates, Inc.

2.2 Sampling Methods

Detail descriptions of the soils encountered, together with recorded blow counts from TxDOT Cone Penetrometer Tests, are provided on the boring logs presented on Figures A-1 through A-14 in Appendix A. A key to symbols and terms used on the boring logs is given on Figure A-15 in Appendix A. The consistency (strength description) of cohesive soils is based on test data from

4 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas triaxial compression test (TAT) and TxDOT cone penetrometer data, where TAT data is not available.

Measurements of the depth to water were taken in the open boreholes during drilling. The results of these observations are noted at the bottom of the boring logs.

After taking final measurements of the depth to groundwater at each boring location, each of the open boreholes, were grouted with cement-bentonite grout.

5 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

3.0 LABORATORY TESTING

Measurements of moisture-density relationships were conducted based on Tex-114-E on a composite sample of near surface clay (0 to 10 feet). Texas Triaxial Compression tests (Tex-117-E) were performed on the composite sample of the near surface clay soil.

Specimen of the existing pavement surface course (asphalt) was tested for its asphalt content, gradation, maximum theoretical specific gravity, bulk density and Haveem Stability.

Results of most laboratory tests are tabulated on the boring logs presented on Figures A-1 through A-14 in Appendix A. The results of the compaction test (Tex-114-E) conducted on a composite sample of clay subgrade soils are presented on Figure B-1 in Appendix B. The results of

6 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

Texas Triaxial Compression tests (Tex-117-E) are presented on Figures B-2a through B-2c. The results of asphalt content, gradation, maximum theoretical specific gravity, bulk density and Haveem Stability conducted on the asphaltic surface course are given on Figure B-3 in Appendix B.

7 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

4.0 SITE CHARACTERIZATION

4.1 Site Geology

4.2 Existing Pavement

The existing pavement as revealed by borings B-1 through B-14 consists of 1.5 to 4 inches of asphalt over 7 to 12 inches of base material. The base material included shell and sand mix and crushed concrete. The details of existing pavement are summarized below:

Boring Asphalt, inches Base, inches B-1 2 8 Shell and Sand B-2 2.5 6.25 Shell B-3 4 6.25 Shell B-4 3 5.5 Sand and shell mix B-5 3 6 Shell B-6 3 7 Shell B-7 3.5 6.5 Shell B-8 2.5 7.5 Gravel 2 5.5 Crushed Concrete over 2.5 Shell and B-9 Gravel mix

8 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

Boring Asphalt, inches Base, inches B-10 2 5 Crushed Concrete B-11 2 6 Crushed Concrete over 3.5 Shell B-12 2 4 Crushed Concrete over 6 Shell B-13 1.5 2 Crushed Concrete over 5.125 Shell B-14 1.5 3 Crushed Concrete over 4 Limestone

4.3 Soil Stratigraphy

The subsurface soils below the existing paving, as revealed by borings B-1 through B-14, consist of very soft to stiff dark gray, brown and gray clay and silty/sandy clay to a depth of 5 to 15 feet, the termination depth of the borings. In boring B-13, a layer of loose silt was encountered between depths of 3 and 5 feet, the explored depth of boring.

The clay is of high to very high plasticity with liquid limits ranging from 50 to 91 and plasticity indices ranging from 29 to 59. The silty/sandy clay is of medium to high plasticity with liquid limits ranging from 26 to 41 and the plasticity indices ranging from 8 to 24. The fines content (percent passing No. 200 sieve) sandy clay is about 59 percent and the fines content of silty clay and clay ranges from 81 to 99 percent. The fines content of silt is about 90 percent.

4.4 Groundwater

No groundwater was encountered in all the borings drilled for this study.

It should be noted that various environmental and man-made factors such as amount of precipitation, could substantially influence groundwater level.

9 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

5.0 GEOTECHNICAL RECOMMENDATIONS

5.1 General

5.2 Open-Cut Excavation

5.2.1 Geotechnical Parameters. Based on the soil conditions revealed by the borings, geotechnical parameters were developed for the open cut excavation for the proposed culverts. The geotechnical design parameters are provided in Table 2. For design, the groundwater level should be assumed to exist at the ground surface, since this condition may exist after a heavy rain or flooding.

• Excavation Shallower Than 5 Feet – Excavations that are less than 5 feet (critical height) deep should be appropriately protected when any indication of hazardous ground movement is anticipated.

• Excavation Deeper Than 5 Feet - Excavations that are deeper than 5 feet should be sloped, shored, sheeted, braced or laid back to a stable slope or supported by some other equivalent means or protection such that workers are not exposed to moving ground or

10 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

cave-ins. The slopes and shoring should be in accordance with the trench safety requirements per OSHA Standards. The following items provide design criteria for trench stability.

(ii) Excavation Support Earth Pressure. Based on the subsurface conditions indicated by this investigation and laboratory testing results, the excavation support earth pressure diagrams were developed and are presented on Figure 3. The pressure diagram can be used for the design of temporary excavation bracing. For a trench box, a lateral earth pressure resulting from an equivalent fluid with a unit weight of 91 pcf is recommended. The above value of equivalent fluid pressure is based upon an assumption that the groundwater level is near the ground surface, since these conditions may exist after a heavy rain or flooding. Effect of surcharge loads at the ground surface should be added to the computed lateral earth pressure. A surcharge load, q, will typically result in a lateral load equal to 0.5 q.

(iii) Bottom Stability. In braced cuts, if tight sheeting is terminated at the base of the cut, the bottom of the excavation can become unstable under certain conditions. This condition is governed by the shear strength of the soils and by the differential hydrostatic head between the groundwater level within the retained soils and the groundwater level at the interior of the trench excavation. For cuts in cohesive soils, as predominantly encountered in all the borings for the excavation depths of 5 feet, the stability of the bottom can be evaluated in accordance with the procedure outlined on Figure 4.

11 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

5.2.3 Groundwater Control. Excavations for the proposed culverts may encounter groundwater seepage to varying degrees depending upon groundwater conditions at the time of construction and the location and depth of excavation. In cohesive soils, as encountered in all the borings for the excavation depths of 5 feet, groundwater may be managed by collection in trench bottom sumps for pumped disposal.

It is recommended that the groundwater conditions be verified at the time of construction.

5.3 Structures

5.3.1 Description. The structures associated with this project are two (2) culverts with 30- inch diameter RCP. The depth of the proposed culverts is approximately 5 feet.

5.3.2 Foundation Conditions. Foundation conditions were explored by borings B-1, B-5, B-6, B-7 and B-14. Based on the soil conditions revealed by the borings, the culverts bases will be in medium stiff to very stiff clay and silty clay.

5.3.3 Foundation Design Recommendations. The following items provide recommendations and design criteria for construction of the culverts.

• Allowable Bearing Pressures. An allowable (net) bearing pressure of 1,500 psf may be used for the design of structures placed at a depth of 5 feet (into soft to stiff clay and silty clay).

• Bottom Stability. The bottom stability should be followed as out lined in Section 5.2.2 of this report.

• Lateral Earth Pressure. The pressure diagram presented on Figure 3 can be used for the design of braced excavation. The lateral earth pressure diagram presented on Figure 5 is applicable for the design of the permanent walls.

12 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

• Hydrostatic Uplift Resistance. Structures extending below the groundwater level should be designed to resist uplift pressure resulting from excess piezometric head. Design uplift pressures should be computed based on the assumption that the water table is at ground surface. To resist the hydrostatic uplift at the bottom of the structure, one of the following sources of resistance can be utilized in each of the designs.

a. Dead weight of structure, b. Weight of soil above base extensions plus weight of structure, or c. Soil-wall friction plus dead weight of structure.

The uplift force and resistance to uplift should be computed as detailed on Figure 6. In determining the configuration and dimensions of the structure using one of the approaches presented on Figure 6, the following factors of safety are recommended.

a. Dead weight of concrete structure, Sf1 = 1.10,

b. Weight of soil (backfill) above base extension, Sf2 = 1.5, and

c. Soil-wall friction, Sf3 = 3.0. Friction resistance should be discounted for the upper 5 feet, since this zone is affected by seasonal moisture changes.

5.3.4 Protection of Below Grade Structures. The design of the proper means for protection of below grade structures will depend upon the potential of the aggressivity or corrosivity of soil and groundwater properties. The aggressivity testing was not within the scope of this study. The design of the protection of below grade structures is beyond the scope of services for this study.

5.3.5 Groundwater Control During Construction. The ground water control should be per guidelines as outlined in Section 5.2.3 of this report.

13 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

5.3.6 Structure Backfill. The bedding and backfill for culverts should follow the TxDOT Houston District “Excavation and Backfill Diagrams.”

5.4 Pavement and Subgrade Design

It is understood that as a part of this project, about 9,600 lf of asphalt roadway will be reconstructed. The pavement design presented in this report was developed in accordance with the AASHTO Guide for Design of Pavement Structures, 1993 edition and per TxDOT pavement design procedures.

5.4.1 Design Parameters

Subgrade Soil Properties. Based on the laboratory test data obtained from the natural

subgrade soils, the effective roadbed soil resilient modulus (MR) is estimated to be about 2,562 psi and Texas Triaxial Subgrade Classification is about 6.2.

6 Traffic Data. A traffic count data of 0.4 x 10 – 18 kips ESAL (W18) over a 20 year design period was utilized for the pavement design. This traffic counts is based on the provided traffic data of 800 vehicles per day with 4 percent truck traffic for a 20 year design life with 2 percent annual growth

5.4.2 Recommended Pavement Section. Based on the design parameters described above and the TxDOT design procedures, the thickness of flexible pavement was determined. The recommended pavement section alternatives are given below:

Pavement Course Thickness, inches Asphaltic Concrete Surface 2 Black Base 5 5 to 6% Lime Stabilized Subgrade 8

14 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

Pavement Course Thickness, inches Asphaltic Concrete Surface 2 Crushed Concrete 10 5 to 6% Lime Stabilized Subgrade 8

5.4.3 Preparation of Pavement Subgrade. Based on the boring and laboratory data, the subgrade support soils at the anticipated finish subgrade elevations consist of medium to high plasticity sandy/silty clay in Phase 1 Section and high plasticity clay in Phase II Section. The sandy/silty clay (Phase I Section) should be stabilized with at least 5 percent hydrated lime and clay (Phase II Section) should be stabilized with at least 6 percent hydrated lime to a depth of 8 inches. The actual percentage of lime may be confirmed by laboratory tests at the time of construction.

Subgrade preparation for the proposed pavement should consist of demolition, stripping, backfilling, proof-rolling and stabilization. The following procedures for subgrade are recommended:

1. Strip the surface soil to a suitable depth to remove all surficial vegetation and achieve grade. In any isolated area where soft, compressible or very loose soils are encountered, additional stripping may be required. Stripping should extend to a minimum of 2 feet beyond the edge of the proposed pavement.

2. Surface exposed after stripping should be proof-rolled with a minimum of 3 passes of a 30-ton pneumatic-tired roller or a heavy loaded truck utilizing a tire pressure of approximately 90 psi. If rutting develops, the tire pressure should be reduced. The purpose of the proof-rolling operation is to identify any underlying zones or pockets of soft soils and to remove such weak materials.

3. Lime stabilization of clay subgrade should be performed in accordance with TxDOT Item 260.

15 Geotest Engineering, Inc. Report No. 1140200001 Scott Unit – Repair/Resurface Entrance Road - TDCJ July 7, 2014 Angleton, Texas

6.0 PROVISIONS

This report has been prepared for the exclusive use of Klotz Associates, Inc. and the Texas Department of Criminal Justice for the Scott Unit – Repair/Resurfacing of Entrance Roadway, in Angleton, Texas.

This report shall not be reproduced without the written permission of Geotest Engineering, Inc., Klotz Associates, or TDCJ.