Amendment_No__0002_0002.pdf

(x)

140R6021R0024 x x

1 copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted ; or (c) By separate letter or electronic communication which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGEMENT TO BE

RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR

OFFER. If by virtue of this amendment you desire to change an offer already submitted , such change may be made by letter or electronic communication, provided each letter or electronic communication makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

x

Billings MT 59107

R60

PO Box 36900 Regional Office Great Plains Region Bureau of Reclamation

08/10/2021

13. THIS ITEM ONLY APPLIES TO MODIFICATION OF CONTRACTS/ORDERS. IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

12. ACCOUNTING AND APPROPRIATION DATA (If required) is not extended.is extended, Items 8 and 15, and returning

Offers must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended , by one of the following methods: (a) By completing

The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offers

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

FACILITY CODE CODE

10B. DATED (SEE ITEM 13)

10A. MODIFICATION OF CONTRACT/ORDER NO.

9B. DATED (SEE ITEM 11)

9A. AMENDMENT OF SOLICITATION NO.

CODE

8. NAME AND ADDRESS OF CONTRACTOR (No., street, county, State and ZIP Code)

7. ADMINISTERED BY (If other than Item 6)CODE 6. ISSUED BY

PAGE OF PAGES

4. REQUISITION/PURCHASE REQ. NO.3. EFFECTIVE DATE2. AMENDMENT/MODIFICATION NO.

5. PROJECT NO. (If applicable)

1. CONTRACT ID CODE

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

07/08/2021

CHECK ONE A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE CONTRACT

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority) appropriation data, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(b).

E. IMPORTANT: Contractor is not is required to sign this document and return __________________ copies to the issuing office.

ORDER NO. IN ITEM 10A.

16A. NAME AND TITLE OF CONTRACTING OFFICER (Type or print)15A. NAME AND TITLE OF SIGNER (Type or print)

15C. DATE SIGNED 16B. UNITED STATES OF AMERICA 15B. CONTRACTOR/OFFEROR 16C. DATE SIGNED

(Signature of person authorized to sign) (Signature of Contracting Officer)

Gerri Voto-Braun

STANDARD FORM 30 (REV. 11/2016)

Prescribed by GSA FAR (48 CFR) 53.243

Previous edition unusable

14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible.)

Project Title: ALTUS EAST B AND LUGERT DIKES FOUNDATION MODIFICATIONS, ALTUS DAM, W.C. AUSTIN

PROJECT, OKLAHOMA

See attachment for changes incorporated by this amendment:

Except as provided herein, all terms and conditions of the document referenced in Item 9 A or 10A, as heretofore changed, remains unchanged and in full force and effect .

Amendment No. 0002 Solicitation No. 140R6021R0024

Description of Changes:

1. In Part I – The Schedule, remove Specification Section 01 33 00 – Submittals in its entirety and substitute therefor the attached revised Section 01 33 00.

2. In Part I – The Schedule, remove Specification Section 31 56 20 – Cement-Bentonite Slurry Cuttoff Wall in its entirety and substitute therefor the attached revised Section 31 56 20.

3. In Part I – The Schedule, remove Specification Section 52 00 00 – Drawings in its entirety and substitute therefor the attached revised Section 52 00 00.

4. In Part I – The Schedule, in Section 52 00 00 – Drawings, remove the following drawings and replace with the attached revised drawings:

Sheet No. Drawing No.

9 258-D-60116, Rev 1 dated 08/02/21 10 258-D-60117, Rev 1 dated 08/02/21 11 258-D-60118, Rev 1 dated 08/02/21 12 258-D-60119, Rev 1 dated 08/02/21 13 258-D-60120, Rev 1 dated 08/02/21 14 258-D-60121, Rev 1 dated 08/02/21 15 258-D-60122, Rev 1 dated 08/02/21 16 258-D-60124, Rev 1 dated 08/05/21 17 258-D-60123, Rev 1 dated 08/05/21

5. In Part II – Contract Clauses, Section I – Contract Clauses, remove Page I-2 and substitute therefor the attached revised Page I-2.

6. In Part IV – Representations, Certifications and Instructions, Section L – Instructions, Conditions and Notices to Offerors, remove page L-4 and substitute therefor the attached revised Page L-4.

For convenience, essential changes on the revised solicitation pages are indicated by a vertical line within the margin, whereby the lines or paragraphs are changed from the previous version.

However, all portions of the revised solicitation pages shall apply whether changes thereon have been indicated or not.

Acknowledgement: See Block 11 on the Standard Form 30 regarding acknowledgement by offerors to this amendment. The Government requires acknowledgement by offerors to this amendment at the place designated for receipt of proposals. (Please see Block 19 on the SF- 1442).

Amendment No. 0002 Solicitation No. 140R6021R0024

Receipt of Proposals: The hour and date for receipt of proposals remains the same; 5:00 PM (MDT) on August 13, 2021.

Third Party: If you have provided a copy of this solicitation to another company or individual, please forward this amendment accordingly.

Subcontracting Plan – A word version of the template for the subcontracting plan is included in this amendment and shall be used by large business concerns in the preparation of their draft subcontracting plan.

The site visit attendance list has been provided in this amendment.

The final list of contractor questions and their respective answers are attached for information only.

Altus East B and Lugert Dikes Foundation Modifications Altus Dam W.C. Austin Project Amendment No. 0002

Submittals

Revised - 01 33 00 - 1

SECTION 01 33 00

SUBMITTALS

PART 1 GENERAL

1.01 MEASUREMENT AND PAYMENT

A. Cost:

1. Include in prices offered in the Price Schedule for other items of work.

1.02 REFERENCE STANDARDS

A. American Society of Mechanical Engineers (ASME)

1. ASME Y14.1-12 Decimal Inch Drawing Sheet Size and Format

B. National Institute of Building Sciences (NIBS)

1. NIBS NCS-14 United States National CAD Standards, Version 6

C. Bureau of Reclamation (Reclamation)

1. RSHS Reclamation Safety and Health Standards, including revisions posted at http://www.usbr.gov/safety/rshs/index.html

1.03 DEFINITIONS

A. Days: Calendar days.

B. Required Submittal Number (RSN): Identifies items to be submitted together as a complete submittal.

C. Submittals: Considered “shop drawings” within the terms of the clause at FAR 52.236- 21, Specifications and Drawings for Construction.

1.04 SUBMITTAL REQUIREMENTS

A. In case of conflict between requirements of this section and requirements included elsewhere in these specifications, requirements included in this section take precedence.

B. General:

1. Prepare in English.

2. Label with contract number and title, and RSN.

3. Measurement Units: US Customary Units.

C. Drawings:

Revised - 01 33 00 - 2

1. Minimum Identification in Title Block:

a. Contract number and title.

b. Contractor’s or supplier’s title and drawing number.

c. Date.

2. Provide space next to title block for review stamps.

3. Size: ANSI D size (22 inches by 34 inches).

4. Draw to scale using computer drafting.

a. In accordance with NIBS NCS.

b. Electronic file format: Compatible with AUTOCAD, Version 2018 or later.

c. Compile using “eTransmit” utility in AUTOCAD.

d. Government will provide electronic AutoCAD format template.

e. Title block and sheet format:

1) As shown on Standard Drawing 40-D-7102.

2) Government will supply template.

3) Government will supply specific title block information to be used.

f. Show as-built changes, including revision dates, made during installation.

Indicate changes by clouding.

D. Product Data:

1. Mark manufacturer's data for commercial products or equipment, such as catalog cut sheets.

a. Identify manufacturer's name, type, model, size, and characteristics.

b. Illustrate that product or equipment meets requirements of specifications.

c. Mark items to be furnished in a manner that will photocopy (no highlighter).

d. Strike through items that do not apply.

E. Certifications:

1. Certifications by a registered professional: Signed and sealed by registered professional.

2. Manufacturer’s certifications: Signed by authorized representative of manufacturer.

F. Photographs:

1. Include digital files in .jpeg or similar format.

Revised - 01 33 00 - 3

G. Videos:

1. Include digital file in MP4 format.

2. Submit on thumb drive.

1.05 SUBMITTALS PROCEDURES

A. Submit only checked submittals. Submittals without evidence of Contractor's approval will be returned for resubmission.

B. Submit complete sets of required materials for each RSN as specified in “Submittals Required” column in Table 01 33 00A - List of Submittals. A complete set includes all listed items for RSNs with multiple parts.

C. Submit number of sets specified in “No. of sets to be sent:” columns in Table 01 33 00A - List of Submittals.

1. Electronic submittals:

a. In Portable Document Format (PDF).

1) Optical Character Recognition (OCR).

2) 508 compliant.

3) RSNs having more than one requirement shall be bookmarked.

4) RSNs with requirements for files other than PDF (.XER, .PLF, .DWGs, etc.) shall be combined using WIN Zip.

b. Include RSN transmittal letter.

c. Personally Identifiable Information (PII) shall be encrypted using WINZip or Adobe Acrobat before transmitting electronically.

2. Submit electronic submittals via e-mail, or thumb drive based on size:

a. The Government can receive e-mails up to 25 MB. However, e-mails over 10 MB should be considered extra-large. E-mailing of electronic submittals exceeding 10 MB should only occur after transmittal of extra-large size e-mail has been verified.

b. Address e-mail of electronic submittals less than extra-large size to:

1) sha-GPR-CONSTSVCS@usbr.gov

c. Electronic submittals that are too large to e-mail shall be submitted on thumb drive.

d. Submittals received after 5:00 p.m. Mountain Time, shall be documented as received the next business day.

D. Include the following information in transmittal letters:

1. Contract number and title.

Revised - 01 33 00 - 4

2. RSN for each attached submittal.

3. Responsible code.

4. Identify submittal as initial or resubmittal.

E. Resubmittal of submittals not approved:

1. Mark changes such that they are readily identifiable and show revision date.

a. Resubmitted drawings shall include a revision block with date.

2. Describe reasons for significant changes in transmittal letter.

3. Resubmit returned submittals within 7 days after receiving comments, unless otherwise directed.

4. Requirements for initial submittals apply to resubmittals.

5. Resubmittals shall be complete submittals without reference to the original submittal.

F. Submit each RSN under a separate transmittal letter. Multiple RSNs submitted under a single letter will be returned for resubmittal.

1.06 REVIEW OF SUBMITTALS

A. Time Required:

1. Submittal review will require 28 days for review of each submittal or resubmittal, unless otherwise specified.

2. Time required for review of each submittal or resubmittal begins when complete sets of materials required for a particular RSN are received and extends through return email date.

B. Time in Excess of Specified:

1. The CO may extend contract completion date to allow additional time for completing work affected by excess review time.

a. Time extension will extend the contract completion date based on the excess review time delay.

b. Time extension will not exceed time used in excess of specified number of days for review of submittals or resubmittals.

c. Concurrent days of excess review time resulting from review of 2 or more separate submittals or resubmittals will be counted only once in extending contract completion date.

2. No time extension will be allowed if Contractor fails to make complete action submittals in sequence and within time periods specified.

3. Adjustment for delay will be made only to extent that:

Revised - 01 33 00 - 5

a. Approval was required under contract, and

b. Requests for approval were properly and timely submitted and were approved.

4. Adjustment will be subject to terms of paragraphs (b) and (c) of the clause at FAR 52.242-14, Suspension of Work; however, no such delay shall be deemed to be a “suspension order” as the term is used in that clause.

C. Submittal Response:

1. Response letter will indicate whether submittal is approved, not approved, acceptable, not acceptable, or acknowledged receipt.

a. Revise and resubmit submittals not approved or not acceptable.

b. Do not change designs without approval of CO after drawings, documentation, and technical data have been approved.

1.07 TRANSMITTAL

A. Addresses for codes listed in Table 01 33 00A - List of Submittals:

1. CO: Bureau of Reclamation, Attention MB-5000, P.O. Box 36900, Billings, MT 59107-6900. Physical address: 2021 4th Avenue North, Billings, MT 59101.

2. COR: Bureau of Reclamation, Attention: MB-2600, P.O. Box 36900, Billings, MT 59107-6900. Physical address: 2021 4th Avenue North, Billings, MT 59101.

B. E-mail address for electronic submittals listed in Table 01 33 00A - List of Submittals:

sha-GPR-CONSTSVCS@usbr.gov.

1. Submit electronic submittals that are too large for e-mail to the physical address above.

C. Submittals required by specifications, but not listed in Table 01 33 00A - List of Submittals:

1. Submit in accordance with this section.

2. Submit to COR unless otherwise specified.

PART 2 PRODUCTS

Not Used

PART 3 EXECUTION

Not Used

Revised - 01 33 00 - 6

Table 01 33 00A. - List of Submittals

** CO indicates Contracting Officer, COR indicates Contracting Officer’s Representative.

RSN

Clause or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

1 Performance and Payment Bonds - Construction 52.228-15

Performance and Payment Bonds

Within 10 calendar days after award

CO 1

electronic

2 Additional Bond Security 52.228-2

Additional Bond Security

Within 10 calendar days after award

CO 1

electronic

3 Insurance-Work on a Government Installation 1452.228-70

1) Written certification that the required insurance has been obtained

2) Current certification of insurance for each subcontractor

Before commencing on-site work

CO 1

4 Liability Insurance 1452.228-70

Acceptable Certificate of Liability Insurance

Prior to commencement of work under the contract

CO 1

electronic

5 Equal Opportunity 52.222-26

Information required by Executive Order

112246 (SF-100)

Within 30 days following award

CO 1

electronic

6 Reporting Executive Compensation and First Tier Subcontract Awards 52.204-10

Certification that executive compensation and subcontract awards were reported

Within 10 days of each report being submitted

CO 1

electronic

7 Personal Identity Verification 52.204-09

SF-85 and OF-306 for each employee and subcontractor employee working on site

Within 10 days after receipt of Notice to Proceed or 10 days before commenting work (for new hire)

CO 1

electronic

8 Labor Standards Data 52.222-11

1) List of subcontractors

Within 14 days after award of contract

COR 1

Revised - 01 33 00 - 7 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

9 Labor Standards Data 52.222-11

1) Statement and acknowledgement Form (SF-1413) for each subcontract

Within 14 days after award of contract

COR 1

10 Payrolls and Basic Records 52.222-08

Copies of all payrolls

Weekly COR 1 electronic encrypted electronic encrypted

11 Site Security

WBR 1452.237-80

List of contractor and subcontractor employees

Submitted at least 28 days prior to arrival on site.

Employees must be approved to perform on-site work

COR 0 1

electroni c encrypted

12 Site Security

WBR 1452.237-80

List of vehicles and equipment to be brought on site

Submitted and approved at least 28 days prior to arriving on site

COR 0 1

electronic encrypted

13 Superintendence by the Contractor

Site Superintendence

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

14 Release of Claims 1452.204-70

Release of Claims (DI-137) against the Government

After completion of the work and prior to final payment

CO 1

electronic

01 14 10-1 Use of Site Land Use and Landscape Rehabilitation Plan

Submitted and approved at least 28 days before mobilization

COR 0 1

electronic

01 31 19-1 Project Management and Coordination

Weekly Coordination Meeting Documentation

Submitted 7 days before meeting

COR 0 1

electronic

01 32 10-1 Construction Program

Representative Information

Submitted within 14 days after preconstruction meeting and approved before mobilization

COR 1 1

Revised - 01 33 00 - 8 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

01 32 10-2 Construction Program

Baseline Schedule Submitted 14 days after preconstruction meeting and approved before mobilization

COR 1 1

electronic

01 32 10-3 Construction Program

Updated Schedule Reports

Monthly and approved for progress payments

COR 1 1

electronic

01 32 10-4 Construction Program

Time Impact Analysis

Within 28 days after the CO directs a contract change, or requests proposal for a future modification, With value engineering proposal, or request for equitable adjustment.

COR 1 1

electronic

01 32 10-5 Construction Program

Schedule of Values Submitted 14 days after preconstruction meeting and approved for first progress payment

CO 1 1

electronic

01 35 10-1 Safety Data Sheets Complete LHM and SDS

Submitted and approved at least 28 days before mobilization

0 1 electronic electronic

01 35 10-2 Safety Data Sheets Updated LHM and

SDS

At least 28 days before jobsite delivery of hazardous material not previously listed

COR 0 1

Revised - 01 33 00 - 9 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

01 35 20-1 Safety and Health Safety Program Submitted and accepted at least 28 days before mobilization. See Section 3 of RSHS

COR 0 1

electronic

01 35 20-2 Safety and Health Monthly Accident Summary Report

Monthly COR 0 1 electronic

01 35 20-3 Safety and Health Respirator User Documentation

Submitted and accepted at least 28 days prior to mobilization

COR 0 1

electronic encrypted

01 35 20-4 Safety and Health Crane Operation Certificates

Submitted and accepted at least 28 days prior to mobilization

COR 0 1

electronic

01 35 20-5 Safety and Health Exposure Assessment Form (if applicable)

Within 21 days of exposure

COR 0 1

electronic

01 35 20-6 Safety and Health Other Training Certificates

Submitted and accepted at least 28 days prior to mobilization

COR 0 1

electronic

01 35 20-7 Safety and Health Pandemic Notification

Immediately upon Notification of Positive Results

COR 0 1

electronic encrypted

01 35 20-8 Safety and Health Employee Return to Work Documentation

Immediately upon Notification of Clearance

COR 0 1

electronic encrypted

01 35 30-1 Contractor’s On-site Safety Personnel

Qualifications Submitted and accepted at least 28 days prior to mobilization

COR 0 1

electronic encrypted

01 35 30-2 Contractor’s On-site Safety Personnel

Safety Inspection Reports

Monthly COR 0 1 electronic

01 46 00-1 Quality Procedures Contractor Quality Control Program

Submitted and approved at least 28 days prior to mobilization

Revised - 01 33 00 - 10 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

01 46 00-2 Quality Procedures Contractor’s Daily Reports

Weekly COR 0 1 electronic

01 46 00-3 Quality Procedures Quality Control Supervisor Resume

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic encrypted

01 46 00-4 Quality Procedures Contractor’s Quality Testing Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 46 00-5 Quality Procedures Summary of Monthly Test Results

Monthly COR 0 1 electronic

01 46 20-1 Testing agency Services

Testing Agency Services Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 51 00-1 Temporary Utilities Water Usage Weekly COR 0 1 electronic

01 51 00-2 Temporary Utilities Temporary Water Access Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 52 10-1 Field Office Delivery Schedule and Site Layout

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 55 00-1 Vehicular Access and Parking

Pre-Construction Video

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 55 00-2 Vehicular Access and Parking

Post-Construction Video

At least 2 days before demobilization

COR 0 1

electronic

01 55 00-3 Vehicular Access and Parking

Post-Repair Video Within 14 days of making repairs

COR 0 1

electronic

01 55 00-4 Vehicular Access and Parking

Swale Crossings Submitted and approved at least 28 days prior to mobilization

Revised - 01 33 00 - 11 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

01 55 00-5 Vehicular Access and Parking

Trench Drainpipe Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 55 00-6 Vehicular Access and Parking

Verification and Ground Treatment in Contractor Use Areas

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 55 00-7 Vehicular Access and Parking

Temporary Roads and Ramps

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 56 10-1 Protection of Existing Installations

Plan for Protecting Existing Installations

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 56 15-1 Protection of Existing Utilities

Utility Owner Acknowledgment

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 56 15-2 Protection of Existing Utilities

Utility Protection Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 57 20-1 Environmental Controls

Copy of Applicable Air Quality Permit

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 57 30-1 Water Pollution Control

Stormwater Pollution Prevention Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 57 30-2 Water Pollution Control

Spill Prevention, Control, and Countermeasure (SPCC) Plan

At least 28 days before delivery or storage of oil

COR 0 1

electronic

01 71 20-1 Surveying Surveying Plan At least 28 days before beginning survey work

Revised - 01 33 00 - 12 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

01 71 20-2 Surveying Resumes At least 28 days before beginning survey work; At least 28 days before personnel change

COR 0 1

electronic

01 71 20-3 Surveying Accuracy Check Results

At least 14 days before beginning survey work

COR 0 1

electronic

01 71 20-4 Surveying Completed and Reduced Survey Notes

Within 2 days of completing each set of survey notes

COR 0 1

electronic

01 71 20-5 Surveying Quantity Survey Notes and Computations

Submitted and approved for progress payments

COR 0 1

electronic

01 74 00-1 Cleaning and Waste Management

Waste Production and Disposal Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

01 74 00-2 Cleaning and Waste Management

Waste Production and Disposal Records

Within 7 days of waste disposal

COR 0 1

electronic

01 74 00-3 Cleaning and Waste Management

Environmental Consultant Resume

At least 28 days before beginning environmental assessment

COR 0 1

electronic

01 74 00-4 Cleaning and Waste Management

Environmental Site Assessment

Within 14 days of completion of work

COR 0 1

electronic

01 78 30-1 Project Record Documents

As-built Drawings Within 28 days of completion of work

COR 0 1

electronic

31 02 10-1 Water for Dust Abatement

Dust Abatement Plan

Submitted and approved at least 28 days prior to mobilization

Revised - 01 33 00 - 13 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

31 09 20-1 Piezometers Cutting Off Existing Piezometers Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

31 09 20-2 Piezometers Survey Submitted within 28 days of cutting off piezometers

COR 0 1

electronic

31 23 02-1 Compacting Earth Materials

Test Results Within 1 day of test COR 0 1 electronic

31 23 31-1 Excavation of Existing Rockfill

Excavation Plan Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

31 24 10-1 Embankment, General

Embankment Construction Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

31 24 11-1 Zone 1 Impervious Fill

Zone 1 Laboratory Test Results

Within 3 days of receiving laboratory results

COR 0 1

electronic

31 25 10-1 Erosion Control Erosion Control Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

31 56 20-1 Cement-Bentonite Slurry Cutoff Wall

Qualifications Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

31 56 20-2 Cement-Bentonite Slurry Cutoff Wall

Cement-Bentonite Slurry Cutoff Wall Plan

Submitted and approved at least 28 days prior to mobilization

COR 0 1

electronic

31 56 20-3 Cement-Bentonite Slurry Cutoff Wall

Material Approval Data

Submitted and approved at least 40 days prior to mobilization

COR 0 1

31 56 20-4 Deleted

Revised - 01 33 00 - 14 or

Section Title

Submittals required

Due date or delivery time

Respon-sible code

Sets to be sent: **

CO COR

32 15 10-1 Gravel Surfacing Certification Submitted and approved at least 28 days prior to work

COR 0 1

electronic

32 92 20-1 Seeding and Soil Supplements

Seeding Plan Submitted and approved at least 28 days prior to work

COR 0 1

electronic

32 92 20-2 Seeding and Soil Supplements

Certifications Submitted and approved at least 28 days prior to work

COR 0 1

END OF SECTION

Cement-Bentonite Slurry Cutoff Wall

Revised 31 56 20 - 1

SECTION 31 56 20

CEMENT-BENTONITE SLURRY CUTOFF WALL

PART 1 GENERAL

1.01 MEASUREMENT AND PAYMENT

A. Cement-Bentonite Slurry Cutoff Wall – Lugert Dike:

1. Measurement: Surveyed length of cement-bentonite slurry cutoff wall and depths as determined on site.

a. The top of the slurry cutoff wall shall be elevation 1572.5.

b. The bottom of the slurry cutoff wall shall be established by soundings taken in the slurry trench at the site by the Contractor in accordance with the Contractor Field Quality Control article (3.04).

2. Payment: Unit price offered in the Price Schedule.

a. Includes cement and bentonite materials for slurry cutoff wall.

b. Includes excavation for slurry cutoff wall and monitoring of trench excavation.

c. Includes cost for protecting Zone 5 – Rockfill material on downstream face of dike.

d. Includes cost of leveling existing dike crests for a work platform prior to slurry cutoff wall installation.

e. Includes cost of excavating top of slurry cutoff wall from elevation 1572.5 to elevation 1572.0 prior to placement of Zone 1 slurry cutoff wall cap.

f. Includes cost of providing adequate working pad in contractor use areas.

g. Adjustments will not be made for over-width trench due to overbreak and extra width required to construct trench around curves.

B. Cement-Bentonite Slurry Cutoff Wall – East Dike B:

1. Measurement: Surveyed length of cement-bentonite slurry cutoff wall and depths as determined on site.

a. The top of the slurry cutoff wall shall be elevation 1572.5.

b. The bottom of the slurry cutoff wall shall be established by soundings taken in the slurry trench at the site by the Contractor in accordance with the Contractor Field Quality Control article (3.04).

2. Payment: Unit price offered in the Price Schedule.

a. Includes cement and bentonite materials for slurry cutoff wall.

Revised 31 56 20 - 2

b. Includes excavation for slurry cutoff wall and monitoring of trench excavation.

c. Includes cost for protecting Zone 5 – Rockfill material on downstream face of dike.

d. Includes cost of leveling existing dike crests for a work platform prior to slurry cutoff wall installation.

e. Includes cost of excavating top of slurry cutoff wall from elevation 1572.5 to elevation 1572.0 prior to placement of Zone 1 slurry cutoff wall cap.

f. Includes cost of providing adequate working pad in contractor use areas.

g. Adjustments will not be made for over-width trench due to overbreak and extra width required to construct trench around curves.

1.02 DEFINITIONS

A. Bentonite slurry: Mixture of bentonite and water.

B. Cement-bentonite slurry: Mixture of cement, bentonite, water, and admixtures.

Produced by adding cement and admixtures to bentonite slurry.

C. Excessive Slurry Loss – Excessive slurry loss shall be defined as observed slurry loss of 6 inches of depth per minute within trench excavation.

1.03 REFERENCE STANDARDS

A. American Petroleum Institute (API)

1. API 13A-19 Drilling Fluid Materials

2. API RB 13B-1 Recommended Practice for Field Testing Water-based Drilling Fluids

B. ASTM International (ASTM)

1. ASTM C 31/C 31 M-19 Making and Curing Concrete Test Specimens in the Field

2. ASTM C33/C33M-18 Standard Specification for Concrete Aggregates

3. ASTM C150/C150M-20 Portland Cement

4. ASTM C494/C494M-19 Chemical Admixtures for Concrete

5. ASTM C939/C939M-16A Standard Test Method for Flow of Grout for Pre-placed Aggregate Concrete

6. ASTM D2166/D2166M-16 Unconfined Compressive Strength of Cohesive Soil

7. ASTM D4380-12 Density of Bentonite Slurries

Revised 31 56 20 - 3

8. ASTM D5084-16a Measurement of Hydraulic Conductivity of Saturated Porous Materials Using a Flexible Wall Permeameter

9. ASTM D6910/D6910M-09 March Funnel Viscosity of Clay Construction Slurries

1.04 SUBMITTALS

A. Submit the following in accordance with Section 01 33 00 - Submittals.

B. RSN 31 56 20-1, Qualifications:

1. Evidence of experience and competency to construct a cement-bentonite slurry cutoff wall. Include:

a. Cement-bentonite slurry cutoff wall on-site supervisor resume.

b. Cement-bentonite slurry cutoff wall primary batch plant operator resume.

c. Cement-bentonite slurry cutoff wall excavator operator(s) resume.

d. Quality control monitor resume.

C. RSN 31 56 20-2, Cement-Bentonite Slurry Cutoff Wall Plan:

1. Contractor use area working pad materials and installation details.

2. Description of staffing for each shift.

3. Night-time Equipment and Considerations, if applicable.

4. Anticipated production rates, in square feet per day.

5. Methods and frequency of monitoring trench alignment.

6. Description of proposed method of trench excavation, including equipment and sequence of constructing slurry cutoff wall.

a. Include the power rating curve for the excavator that will be used to excavate the slurry cutoff wall.

7. Slurry Loss Management Plant.

8. Bentonite-water mixing method, storage area size and location, and hydration period.

9. Cement-bentonite-water mixing method, storage, and delivery method.

10. Pumping equipment, capacity, and backup equipment.

11. Type of admixtures to be used and conditions under which they will be used.

12. Means and methods for protecting Zone 5 Rockfill on the downstream face of the dikes from contamination of cement-bentonite excavation spoils during excavation for the slurry cutoff wall.

13. In situ slurry sampler details.

Revised 31 56 20 - 4

14. Method of wasting the following:

a. Cement-bentonite in pump lines due to construction difficulties or slow construction.

15. Method of flushing pump lines and disposal of flushing water after use and conditions under which flushing would be done.

16. Equipment and method of sounding bottom of slurry trench.

17. Method of sampling bottom of slurry trench.

18. Method of winter operation of slurry system, including protection of exposed slurry surfaces and prevention of freezing water in lines and pumps.

19. Haul traffic plan.

20. Method for removing loose material from surface of granite.

D. RSN 31 56 20-3, Material Approval Data:

1. Name and manufacturer of each admixture.

a. Manufacturer’s name and specific brand names, product description and data sheets, mixing instructions, recommended dosage, chloride content, and precautions for its use.

b. Product samples: Submit product samples to Reclamation’s Concrete and Structural Laboratory a minimum of 40 days prior to beginning work.

1) Superplasticizer: 2 gallons, minimum.

2) Set Retarders and other admixtures:

a) 2 pounds minimum for powdered admixtures.

b) 2 gallons minimum for liquid admixtures.

2. Cementitious materials certifications and test reports:

a. Manufacturer’s certification and test reports for each lot of cementitious material from which shipments are drawn.

1) Test reports less than 3 months old.

2) Submittal of certification and test reports shall not relieve Contractor of responsibility for furnishing materials meeting specified requirements.

b. Product samples: Submit a 50-pound product sample to Reclamation’s Concrete and Structural Laboratory a minimum of 40 days prior to beginning work.

3. Bentonite:

a. Product certification report showing that materials meet specified requirements.

Revised 31 56 20 - 5

b. Product samples: Submit a 10-pound product sample to Reclamation’s Concrete and Structural Laboratory a minimum of 40 days prior to beginning work.

4. Trial batch test results if applicable.

a. 28-day permeability in accordance with ASTM D5084.

b. 28-day UCS in accordance with ASTM C31 and D2166.

c. Time of Efflux in accordance with ASTM C939.

E. Deleted.

1.05 PROJECT CONDITIONS

A. Groundwater and Foundation Conditions – Refer to Section 53 10 00 – Geologic Investigations and Section 53 20 00 – Records of Geologic and Subsurface Investigations.

1. The Contractor shall be prepared to mitigate for potential slurry loss during construction. Loose sand conditions and soft fine-grained materials are present in the dike foundations.

2. The Government has no evidence of erosion of foundation materials due to seepage exiting downstream of the dikes.

a. The Government’s subsurface investigation programs have not found any evidence of voids within the dike foundations.

b. Erosion of foundation materials due to seepage has not been observed during the extensive long-term visual monitoring of the seepage downstream of the dikes.

c. A safety of dam’s modification was performed in 2017 and 2018 at Lugert and East Dike B to address dam safety issues related to open drainage trenches that were located within approximately 30 feet of the downstream toe of the dikes.

1) The dike modification performed in 2017 and 2018 did not observe voids within the 5 to 10-foot deep drainage trenches.

2) The trenches were backfilled with filter and drain materials and a perforated pipe.

B. Dike Embankment Conditions – Refer to Section 53 10 00 – Geologic Investigations and Section 53 20 00 – Records of Geologic and Subsurface Investigations.

C. Maximum depth of slurry cutoff wall is expected to be less than 80 feet as shown on the drawings.

D. The contractor use areas shown on the drawings were selected in areas with no surface seepage observed when the reservoir is below the restricted elevation of 1554.0.

Revised 31 56 20 - 6

E. The Government anticipates soft ground conditions within the contractor use areas. The clayey foundation soils may not provide adequate bearing capacity for equipment travel and material storage.

1. Improvements to the contractor use areas is likely needed to provide adequate bearing capacity.

F. In the event of a large rainfall event that results in the reservoir temporarily exceeding the restricted water surface elevation of 1554.0 feet, seepage and wet conditions are likely downstream of the dikes.

G. Storage tanks or above ground slurry ponds are required due to the potential high groundwater elevations downstream of the dikes. Subsurface slurry ponds are not allowed.

H. Equipment shall be capable of operating and performing satisfactorily in freezing conditions.

I. Refer to Section 51 00 40 – Cement-Bentonite Mix Design for Altus Dam Cutoff Wall No. 2.

J. Refer to specification Section 31 24 20 - Zone 6 Cement-Bentonite Slurry Cutoff Wall Spoils for placement of excavated materials from slurry cutoff wall excavation.

K. Dispose of wasted grout materials in accordance with Section 01 74 00 – Cleaning and Waste Management.

1.06 QUALIFICATIONS

A. Cement-Bentonite Slurry Cutoff Wall On-site Supervisor:

1. Minimum experience in responsible charge for slurry cutoff wall construction similar in nature to that required by this contract: 10 years.

B. Primary Batch Plant Operator(s):

1. Minimum batch plant equipment operating experience in responsible charge of construction similar in nature to that required by this contract: 10 years.

C. Cement-Bentonite Slurry Cutoff Wall Excavator Operator(s):

1. Minimum slurry cutoff wall excavator equipment operating experience for similar projects: 10 years.

D. Quality Control Monitor

1. Minimum quality control monitoring experience for projects similar in nature to that required by this contract: 5 Projects.

E. Maintain sufficient qualified personnel to perform required work.

Revised 31 56 20 - 7

PART 2 PRODUCTS

2.01 MATERIALS

A. Cement:

1. ASTM C150, Type II.

2. Meet equivalent alkalies requirements of ASTM C150 - Table 2

3. Meet false-set requirements of ASTM C150 - Table 4.

B. Bentonite: Natural sodium cation-base montmorillonite, premium-grade powdered Wyoming bentonite, in accordance with API 13A.

1. Chemically treated bentonite not allowed.

2. Sodium montmorillonite clay purity, minimum: 85 percent.

3. Moisture content as packaged, maximum: 10 percent.

C. Water:

1. Water may be obtained from the reservoir, see Section 01 51 00 – Temporary Utilities.

D. Admixtures:

1. The use of lignosulfonate based water reducing admixture is allowed provided that it meets the following requirements:

a. ASTM C494 Type A, D, F, or G.

b. Do not use chemical admixtures that contain more than 0.1 percent chloride, by weight.

c. Maximum dosage rate: 1 percent by weight of cementitious materials or as approved by COR.

2. The use of non-lignosulfonate-based water reducing admixtures is not allowed.

3. Additional Admixtures: As submitted and approved.

2.02 SLURRY MIX

A. Government will design cement-bentonite slurry mix.

B. Cement-Bentonite Slurry Mix: Consist of ingredients within the proportion ranges shown in Table 31 56 20A - Cement-Bentonite Slurry Mix.

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Table 31 56 20A - Cement-Bentonite Slurry Mix

Mix Component Percent Added by Water Weight

Cement 22 percent

Bentonite 6 percent

Admixtures As submitted and approved

C. Variations to the proportions shown in Table 31 56 20A – Cement-Bentonite Slurry Mix are not allowed.

D. The use of alternative cementitious materials such a slag or fly ash is not allowed.

E. The government has completed a trial batch of the slurry mix provided in Table 31 56 20A. This information is available in Section 51 00 00 – Information Available to Offerors.

F. Admixtures:

1. The use of admixtures may be allowed to improve constructability.

2. The dosage rate for admixtures shall be determined by the Contractor.

3. The contractor shall submit trial batch test results to confirm the use of an admixture has not adversely affected the Government’s mix design.

a. Trial batch test results are not required for the addition of a lignosulfonate based water reducing admixture with a dosage rate of less than or equal to 1 percent by weight of cementitious materials.

b. Trial batch test result requirements for all other admixtures or dosage rates exceeding what is stated above:

1) Permeability of hardened slurry mix, ASTM D5084: Less than or equal to 2x10-6 centimeters per second at 28 days.

2) Unconfined compressive strength of hardened slurry mix, ASTM C31 and D2166:

a) Minimum 28 days: 45.0 lb/in2.

b) Maximum 28 days: 75.0 lb/in2.

3) Time of Efflux:

a) Less than 12 seconds, in accordance with ASTM C939.

b) Less than 60 seconds in accordance with ASTM D6910.

c. Trial batch testing performed by the contractor shall be performed using site water.

Revised 31 56 20 - 9

d. Government will evaluate test results for acceptance.

G. The slurry shall be maintained at a temperature between 45 degrees and 80 degrees Fahrenheit until placed within the slurry cutoff wall trench, including the duration of time that the slurry remains or travels in the hoses.

1. Uniformly heat or cool water and materials before mixing to obtain a grout mixture temperature within specified limits.

2. Measurement shall be in accordance with ASTM C1064.

2.03 SLURRY CUTOFF WALL CAP MATERIALS

A. Zone 1 Impervious Fill Material: In accordance with Section 31 24 11 – Zone 1 Impervious Fill.

2.04 SAND

A. The Government has sand stockpiled on site downstream of Lugert Dike and East Dike B if needed in the event of slurry loss.

B. Volume Available:

1. Lugert Dike: Approximately 200 cubic yards.

2. East Dike B: Approximately 100 cubic yards.

C. Gradation – Meets the requirements of ASTM C33 fine aggregate.

PART 3 EXECUTION

3.01 EQUIPMENT

A. Batch Plant Equipment:

1. Mixers: High-shear colloidal-type.

a. Fitted with adequate measuring devices, such as water meters and balances, to ensure that materials are being mixed in the correct proportions.

1) Meters and balances:

a) Control delivery of material and water so inaccuracies in feeding and measuring shall meet the specified density requirements.

b) Provide totalizer(s) and a water meter mounted on the plant, readily accessible by COR.

Revised 31 56 20 - 10

c) Use range of scale suitable for the batching equipment supplied. Provide maximum range twice the anticipated maximum batch amounts.

d) Demonstrate testing and calibration procedures to COR before beginning slurry cutoff wall installation.

e) Test and calibrate scales, totalizer(s), water meters, and electronic signal equipment at batch plant at least once a week in the presence of COR, or whenever out of specifications.

f) Keep calibration equipment and supplies onsite for duration of slurry cutoff wall installation.

g) Immediately replace defective equipment.

h) CO may suspend operations until equipment is functional.

i) Keep at jobsite extra scale and meters for immediate replacement of defective units.

b. Equipped with high-speed, diffuser-type centrifugal mixing pump operating at 1,500 to 2,000 revolutions per minute during mixing.

c. Direct return flow from centrifugal mixing pump tangentially into the cylindrical tank near the top to create a vortex.

2. Bentonite Slurry Holding Tank(s) or Pond(s):

a. Holding tank(s) or above ground slurry pond(s) are required for mixing and storing bentonite slurry.

b. Capacity: Sufficient to allow full hydration of the bentonite.

c. Equipped with adequate equipment to agitate the bentonite slurry to maintain particles in suspension.

d. The use of below ground slurry pond(s) is not allowed.

3. Cement-Bentonite Slurry Holding Tank(s):

a. Capacity: Provide a holdover mechanical agitator tank greater than or equal to in volume to the mixer.

b. Equipped with adequate equipment to agitate the cement-bentonite slurry to maintain particles in suspension.

4. Pumping equipment:

a. Pumps: Capable of pumping slurries from batch plant to trench excavation or location where material can be wasted.

b. Include standby pumps as part of batch plant, capable of being placed in operation with no more than 30-minute notice.

c. Pipes and hoses:

Revised 31 56 20 - 11

1) Pipes and hoses: Capable of withstanding pumping pressures.

2) Provide with couplings capable of withstanding pumping pressures.

3) Repair leaking joints, or pipes, or hoses immediately following notification.

5. Auxiliary equipment:

a. Sampling facilities: Adequate for obtaining slurry samples as specified.

b. Temperature support equipment:

1) Required to maintain slurry mixes with temperature range of 45 to 80 degrees F.

2) May include water heaters and insulating materials.

6. System flushing:

a. Demonstrate capacity to flush the cement-bentonite slurry supply lines if cement-bentonite slurry setup is likely due to construction delays, poor mixing, or other cause.

B. Excavating equipment:

1. Capable of excavating 36-inch-wide trench through compacted embankment, overburden soil and underlying foundation rock. Refer to Section 53 10 00 – Geologic Investigations for information on underlying rock.

2. Capable of continuously excavating 36-inch-wide trench to the full depth shown on the drawings.

3. The Contractor shall modify or replace equipment when necessary, , to maintain production rates in accordance with the Contractor’s construction schedule.

4. A long-reach excavator capable of excavating the shale bedrock to a maximum depth of 80 feet shall be used to excavate the slurry cutoff wall.

5. Provide suitable bucket with ripper teeth for excavation into shale bedrock.

3.02 CONSTRUCTION

A. Slurry Loss Management Plan

1. The contractor shall provide stabilization measures to maintain slurry levels in trench if excessive slurry loss occurs, which may include the following:

a. Emptying all cement-bentonite slurry available in mixing and holding tanks.

b. Increase viscosity of cement-bentonite slurry.

c. Add sand or silicate reactant.

d. Backfill trench.

Revised 31 56 20 - 12

B. Slurry preparation:

1. Thoroughly mix and hydrate bentonite slurry to attain complete dispersion of the bentonite particles. Do not mix bentonite slurry in trench or by hand.

2. Store bentonite slurry in holding tank(s) or above ground slurry pond(s) for sufficient time to allow full hydration of bentonite.

a. Full hydration of bentonite is considered accomplished when the viscosity properties of bentonite slurry stabilize.

1) Minimum Marsh Funnel viscosity, ASTM D6910: 34 seconds.

2) Minimum density, ASTM D4380: 64 lb/ft3.

3) Filtrate Loss, API 13B-1: Less than 25 milliliters.

b. Continuously agitate bentonite slurry in holding tank(s) until used.

1) Agitation of slurry may be discontinued overnight or during weekends when no work is performed.

2) At beginning of each workday, stored bentonite slurry shall be agitated for at least 1/2-hour, before being used for production of cement-bentonite slurry.

3. After bentonite is fully hydrated, blend bentonite slurry with cementitious materials and admixtures in high-shear colloidal type mixer. Do not mix slurry in trench or by hand.

a. Mix cementitious materials and bentonite slurry until full dispersion of cementitious particles is obtained.

b. Add approved admixtures.

c. Maximum Marsh Funnel viscosity, ASTM D6910: 60 seconds.

d. Density:

1) Minimum: 72.9 lb/ft3.

e. Transfer cement-bentonite slurry from mixer to holding tank(s).

1) Agitation in holding tank(s) shall impart adequate energy to cement-bentonite slurry to maintain particles in suspension.

2) Agitate cement-bentonite slurry continuously during storage.

3) Waste cement-bentonite slurry stored more than 2 hours, at no cost to the Government.

a) Dispose of waste cement-bentonite slurry at locations shown on drawings. Cement-bentonite slurry shall not be wasted on upstream face of dam.

C. Slurry Cutoff Wall Construction:

Revised 31 56 20 - 13

1. Protect Zone 5 rockfill on downstream face of dikes from contamination of excavation spoils during excavation of slurry cutoff wall.

2. Continuously excavate trench to the lines and grades shown on the drawings.

a. Alignment of the cement-bentonite slurry cutoff wall shall be located as shown on drawings.

b. Minimum trench width: 36 inches.

c. Slurry Cutoff Wall Depth:

1) Shale Foundation Slurry Cutoff Wall Tie-in:

a) The majority of the slurry cutoff wall will be founded on shale bedrock as shown on the drawings.

b) The bottom of the slurry cutoff wall shall be 5 feet into shale bedrock as shown on the drawings or as determined by the COR.

c) Additional excavation may be required as directed by CO.

2) Granite Foundation Slurry Cutoff Wall Tie-in:

a) The slurry cutoff wall will be founded on granite as shown on the drawings at the left abutment of Lugert Dike and the right abutment of East Dike B.

b) The bottom of the slurry cutoff wall shall be founded on the surface of the Granite.

c) Loose material on the surface of the Granite shall be removed with the excavator.

d) Ripping and removal of granite is not allowed.

e) After loose material is removed from the surface of the granite by the excavator, air-lifting or other approved method shall be used to clean the bedrock surface of any entrapped sediment when installing slurry cutoff wall adjacent to granite.

d. When determined by the COR, excavate and deposit material from the bottom of the trench to allow the Government to inspect excavated material and determine type of material located at the bottom of the trench.

3. Introduce cement-bentonite slurry into the trench at start of excavation.

4. Maintain cement-bentonite slurry within 6-inches below top of trench during excavation.

a. Trench excavation process shall not proceed faster than the capacity of slurry mixing and handling equipment to keep the trench full of slurry.

5. If trench experiences excessive slurry loss:

Revised 31 56 20 - 14

a. Stop excavating immediately when slurry loss is observed.

b. Implement approved slurry loss procedures.

6. If trench excavation is halted for a duration that exceeds 120 minutes, at least 5 feet horizontally of hardened cement-bentonite slurry shall be excavated for the entire depth of the trench when the excavation is restarted.

7. Deposit excavated trench material on downstream face of dike in accordance with Section 31 24 20 – Zone 6 Cement-Bentonite Slurry Cutoff Wall Spoils.

a. Immediately remove excavated trench material from the dike crest.

8. Provide moist cover over fresh slurry for a minimum of 24 hours after placement.

9. When air temperature is less than 40 degrees F or is expected to fall below 40 degrees F, protect top of cement-bentonite slurry placed within the previous 48 hours with an insulating blanket.

10. After initial slurry set, excavate cement-bentonite slurry to Elevation 1572.0.

a. Time between completing a section of trench and excavating cement-bentonite slurry to Elevation 1572.0:

1) Minimum: 3 days.

2) Maximum: 7 days.

b. Perform additional excavation as determined by the COR to remove defects in the excavated slurry cutoff wall surface.

1) Backfill defects up to elevation 1572.0 with cement-bentonite slurry.

c. Excavated…