W912QR25R0016_CERT_Final_Specs-0003.pdf

CIVIL/OPS/ENVIRONMENTAL BR

ATTN: ADYSON MEDLEY

600 DR M L KING JR PL RM 821

LOUISVILLE KY 40202-2236

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

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

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

30-105-04EXCEPTION TO SF 30

APPROVED BY OIRM 11-84

STANDARD FORM 30 (Rev. 10-83) Prescribed by GSA

FAR (48 CFR) 53.243

SEE SUMMARY OF CHANGES

1. CONTRACT ID CODE PAGE OF PAGES

1 2

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

16C. DATE SIGNED

BY

16B. UNITED STATES OF AMERICA15C. DATE SIGNED15B. CONTRACTOR/OFFEROR

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

8. NAME AND ADDRESS OF CONTRACTOR (No., Street , County, State and Zip Code) X W912QR25R0016

X 9B. DATED (SEE ITEM 11)

20-Dec-2024

10B. DATED (SEE ITEM 13)

9A. AMENDMENT OF SOLICITATION NO.

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

X The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offer is extended, X is not extended.

Offer 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 Items 8 and 15, and returning 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 telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGMENT 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 telegram or letter, provided each telegram or letter makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

12. ACCOUNTING AND APPROPRIATION DATA (If required)

13. THIS ITEM APPLIES ONLY TO MODIFICATIONS OF CONTRACTS/ORDERS.

IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

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

CONTRACT ORDER NO. IN ITEM 10A.

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, appropriation date, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(B).

C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority)

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

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

10A. MOD. OF CONTRACT/ORDER NO.

U0003

2. AMENDMENT/MODIFICATION NO. 5. PROJECT NO.(If applicable)

6. ISSUED BY CODE

U. S. ARMY ENGINEER DISTRICT, LOUISVILLE

600 DR. MARTIN LUTHER KING, JR. PLACE

ROOM 821

LOUISVILLE KY 40202-2239

W912QR 7. ADMINISTERED BY (If other than item 6)

4. REQUISITION/PURCHASE REQ. NO.

CODE W912QR

FACILITY CODECODE

EMAIL:TEL:

3. EFFECTIVE DATE

6-MAR-2025

W912QR25R0016_CERT_Final_Specs-0003

W912QR25R0016

SECTION SF 30 BLOCK 14 CONTINUATION PAGE

SUMMARY OF CHANGES

SECTION SF 30 - BLOCK 14 CONTINUATION PAGE (SF 30)

The following have been added by full text:

AMENDMENT 0003 CHANGES

Solicitation W912QR25R0016 for Rough River Dam Modification is hereby amended with the following changes:

1. The following SPECIFICATION SECTIONS have been revised and replaced in their entirety:

03 37 29 14 21 13 31 56 10.00 06

CONCRETE FOR CUTOFF WALL

ELECTRIC TRACTION FREIGHT ELEVATORS

CUTOFF WALL CONSTRUCTION

2. The following PLANS have been revised and replaced in their entirety:

V-003

OTW CS101

OTW CS114

OTW CU101

OTW CG502

CTW CG200

CTW CG202

CTW CG502

CTW CG505

CONTRACTOR WORK LIMITS

OUTLET WORKS OVERALL SITE PLAN

OUTLET WORKS OVERALL SITE PLAN 6 OF 16

OVERALL UTILITY PLAN

BLASTING AREA INSTRUMENTATION PLAN (OVERALL)

OVERALL CUTOFF WALL - PROFILE

CUTOFF WALL - PROFILE

CRITICAL AREA A SEQUENCE OF WORK

CONDUIT ABANDONMENT CONCRETE PLACEMENTS

3. The acronym "USACE" has been deleted from Class Deviation 2025-O0002 dated dated 7 February 2025 as referenced in Amendment No. 2

4. The following DOCUMENT has been added for requested information:

Memorandum for Record Concrete Materials Testing and Enclosures

(End of Summary of Changes)

SECTION 03 37 29 Page 1

AMENDMENT 0003

CERTIFIED FINAL

P2#: 145870 Rough River Falls of Rough, KY Dam Safety Mod Phase II

SECTION 03 37 29

PART 1 GENERAL

1.1 SCOPE

CONCRETE FOR CUTOFF WALL

11/21

Amendment 0003

Section 03 00 00 GENERAL CONCRETE REQUIREMENTS covers general concrete and materials requirements that are applicable to multiple concrete specifications within the Contract, including QA/QC, general concrete materials, and batch plant requirements. CONCRETE FOR CUTOFF WALL provides specifications and requirements for the concrete used to construct the cutoff wall. Concrete shall be provided from a properly permitted batch plant located within the Contractor Work Limits shown on the drawings. The Batch plant must be dedicated to cutoff wall concrete for the shift while cutoff wall concrete is being placed. Cutoff wall concrete must be proportioned for tremie placement below water. Concrete to be placed in Critical Area A and Critical Areas B1-B4 must contain an anti-washout admixture for placements with the temie pipe embedded to a depth of at least 5 feet above the top of rock (as determined by the rock elevation for the element during excavation). Concrete placed outside of these critical areas will not require the anti-washout admixture; even if cast within bedrock.

1.1.1 Special Coordination

Due to the potential for blasting activities to be concurrent to some phases of cutoff wall construction, careful coordination by the Contractor is required to ensure no blast occurs immediately after fresh concrete has been placed and that the concrete elements have set to be sufficiently considered "Green Concrete". The Contractor shall ensure that any scheduled blasting is adjusted sufficiently for the cutoff wall placement and curing schedule with the blasting design adjusted accordingly to prevent damage to the newly placed elements. Special coordination for blasting and blasting limits near green concrete is contained in the blasting specs below.

31 23 17.00 06 UNDERWATER BLASTING

31 23 18.00 06 SURFACE BLASTING

31 56 10.00 06 CUTOFF WALL CONSTRUCTION

1.2 MEASUREMENT AND PAYMENT

No separate or direct payment will be made for the work under this Section, and such work will be considered as a subsidiary obligation of the Contractor per specification SECTION 31 56 10.00 06 CUTOFF WALL CONSTRUCTION paid for under CUTOFF WALL COMPLETE - SOIL, ROCK OVER

EXCAVATION, CONCRETE.

1.3 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

SECTION 03 37 29 Page 2

AMERICAN CONCRETE INSTITUTE INTERNATIONAL (ACI)

ACI 207.2R (2007) Report on Thermal and Volume Change Effects on Cracking of Mass Concrete

ACI 211.1 (2022) Selecting Proportions for

Normal-Density and High-Density Concrete-Guide

ACI 304R (2000; R 2009) Guide for Measuring, Mixing, Transporting, and Placing Concrete

AMERICAN PETROLEUM INSTITUTE (API)

API RP 13B-1 (2019; Errata 2020; Errata 2021; Errata 2023) Field Testing Water-Based Drilling Fluids

API Spec 13A (2019; Addendum 2020; Addendum 2022;

Errata 2024) Drilling Fluids Materials

ASTM INTERNATIONAL (ASTM)

ASTM C1017/C1017M (2013; E 2015) Standard Specification for Chemical Admixtures for Use in Producing Flowing Concrete

ASTM C1064/C1064M (2023) Standard Test Method for

Temperature of Freshly Mixed Hydraulic-Cement Concrete

ASTM C1077 (2024) Standard Practice for Agencies

Testing Concrete and Concrete Aggregates for Use in Construction and Criteria for Testing Agency Evaluation

ASTM C117 (2023) Standard Test Method for Materials

Finer than 75-um (No. 200) Sieve in Mineral Aggregates by Washing

ASTM C123/C123M (2023) Standard Test Method for

Lightweight Particles in Aggregate

ASTM C1240 (2020) Standard Specification for Silica Fume Used in Cementitious Mixtures

ASTM C1260 (2023) Standard Test Method for Potential

Alkali Reactivity of Aggregates (Mortar-Bar Method)

ASTM C127 (2015) Standard Test Method for Relative

Density (Specific Gravity) and Absorption of Coarse Aggregate

ASTM C128 (2022) Standard Test Method for Relative

Density (Specific Gravity) and Absorption of Fine Aggregate

SECTION 03 37 29 Page 3

ASTM C131/C 131M (2020) Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine

ASTM C136/C 136M (2019) Standard Test Method for Sieve

Analysis of Fine and Coarse Aggregates

ASTM C138/C138M (2023) Standard Test Method for Density ( Unit Weight), Yield, and Air Content (Gravimetric) of Concrete

ASTM C142/C142M (2017; R 2023) Standard Test Method for

Clay Lumps and Friable Particles in Aggregates

ASTM C143/C143M (2020) Standard Test Method for Slump of

Hydraulic-Cement Concrete

ASTM C150/C150M (2022) Standard Specification for Portland Cement

ASTM C1567 (2023) Standard Test Method for

Determining the Potential Alkali-Silica Reactivity of Combinations of Cementitious Materials and Aggregate (Accelerated Mortar-Bar Method)

ASTM C1602/C1602M (2022) Standard Specification for Mixing

Water Used in Production of Hydraulic Cement Concrete

ASTM C1609/C1609M (2024) Standard Test Method for Flexural

Performance of Fiber-Reinforced Concrete (Using Beam With Third-Point Loading)

ASTM C1611/C1611M (2021) Standard Test Method for Slump Flow of Self-Consolidating Concrete

ASTM C172/C172M (2017) Standard Practice for Sampling Freshly Mixed Concrete

ASTM C183/C183M (2023) Standard Practice for Sampling and the Amount of Testing of Hydraulic Cement

ASTM C192/C192M (2019) Standard Practice for Making and Curing Concrete Test Specimens in the Laboratory

ASTM C231/C231M (2024) Standard Test Method for Air

Content of Freshly Mixed Concrete by the Pressure Method

ASTM C232/C232M (2021) Standard Test Method for Bleeding of Concrete

ASTM C260/C260M (2010; R 2016) Standard Specification for

SECTION 03 37 29 Page 4

Air-Entraining Admixtures for Concrete

ASTM C31/C31M (2024) Standard Practice for Making and Curing Concrete Test Specimens in the Field

ASTM C33/C33M (2023) Standard Specification for Concrete

ASTM C39/C39M (2023) Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens

ASTM C40/C40M (2020) Standard Test Method for Organic

Impurities in Fine Aggregates for Concrete

ASTM C403/C403M (2023) Standard Test Method for Time of Setting of Concrete Mixtures by Penetration Resistance

ASTM C42/C42M (2020) Standard Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete

ASTM C441/C441M (2017) Standard Test Method for

Effectiveness of Pozzolans or Ground Blast-Furnace Slag in Preventing Excessive Expansion of Concrete Due to the Alkali-Silica Reaction

ASTM C494/C494M (2019; E 2022) Standard Specification for

Chemical Admixtures for Concrete

ASTM C566 (2019) Standard Test Method for Total Evaporable Moisture Content of Aggregate by Drying

ASTM C578 (2023) Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation

ASTM C617/C617M (2023) Standard Practice for Capping Cylindrical Concrete Specimens

ASTM C618 (2023; E 2023) Standard Specification for

Coal Ash and Raw or Calcined Natural Pozzolan for Use in Concrete

ASTM C70 (2020) Standard Test Method for Surface

Moisture in Fine Aggregate

ASTM C87/C87M (2023) Standard Test Method for Effect of Organic Impurities in Fine Aggregate on Strength of Mortar

ASTM C88/C88M (2024) Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or Magnesium Sulfate

SECTION 03 37 29 Page 5

ASTM C94/C94M (2023) Standard Specification for Ready-Mixed Concrete

ASTM C940 (2022) Standard Test Method for Expansion and Bleeding of Freshly Mixed Grouts for Preplaced-Aggregate Concrete in the Laboratory

ASTM C979/C979M (2016) Standard Specification for Pigments for Integrally Colored Concrete

ASTM C989/C989M (2024) Standard Specification for Slag Cement for Use in Concrete and Mortars

ASTM D242/D242M (2019) Standard Specification for Mineral

Filler for Asphalt Mixtures

ASTM D4791 (2019; R 2023) Standard Test Method for Flat Particles, Elongated Particles, or Flat and Elongated Particles in Coarse Aggregate

ASTM D75/D75M (2019) Standard Practice for Sampling

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY (NIST)

NIST HB 44 (2024) Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices

NATIONAL READY MIXED CONCRETE ASSOCIATION (NRMCA)

NRMCA CPMB 100 (2000; R 2006) Concrete Plant Standards

U.S. ARMY CORPS OF ENGINEERS (USACE)

COE CRD-C 100 (1975) Method of Sampling Concrete

Aggregate and Aggregate Sources, and Selection of Material for Testing

COE CRD-C 104 (1980) Method of Calculation of the

Fineness Modulus of Aggregate

COE CRD-C 112 (1969) Method of Test for Surface Moisture in Aggregate by Water Displacement

COE CRD-C 120 (1994) Test Method for Flat and Elongated

Particles in Fine Aggregate

COE CRD-C 130 (2001) Standard Recommended Practice for Estimating Scratch Hardness of Coarse Aggregate Particles

COE CRD-C 143 (1962) Specifications for Meters for

Automatic Indication of Moisture in Fine Aggregate

SECTION 03 37 29 Page 6

COE CRD-C 55 (1992) Test Method for Within-Batch Uniformity of Freshly Mixed Concrete

COE CRD-C 61 (1989A) Test Method for Determining the

Resistance of Freshly Mixed Concrete to Washing Out in Water

COE CRD-C 661 (2006) Specification for Antiwashout

Admixtures for Concrete

EM 1110-2-2000 (1994/2001) Standard Practice for Concrete for Civil Works Structures

ER 1110-1-261 (1999) Engineering and Design - Quality

Assurance of Laboratory Testing Procedures

1.4 SUBMITTALS

Government approval/acceptance by the Resident Office (RO) is required for submittals with a "G" designation; submittals not having a "G" designation are for information only (FIO) or as otherwise designated. When used, a designation following the "G" designation identifies an additional office that will review the submittal for the Government. The following shall be submitted in accordance with LRL Section 01 33 00 SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Proposed Concrete Mixture Proportions; G, DO Once materials for the cutoff wall concrete have been approved and at least 60 days prior to the start of the test section.

Curing and Protection; G, DO The curing medium and methods to be used shall be submitted for review and approval. Cold and hot weather protection shall be included.

Quality Control and Placement Forms; G, DO All forms or checklists to be used for quality control data and placement shall be submitted at least 60 days prior to the start of the Test Section.

Concrete for Cutoff Wall Concreting Plan; G, DO A plan shall be submitted to the Contracting Officer for review and approval at least 60 days prior to the start of the Test Section. See paragraph CONCRETE FOR CUTOFF WALL CONCRETING PLAN.

Cold-Weather Protection; G, DO When concrete is to be placed under cold-weather conditions, a description of the materials and methods proposed for protection of the concrete meeting the requirements of Paragraph COLD-WEATHER PROTECTION shall be furnished at least 60 calendar days in advance of the anticipated need date for review.

SD-02 Shop Drawings

Equipment; G,DO

SECTION 03 37 29 Page 7

SD-03 Product Data

Conveying and Placing Equipment; G,DO Data on the conveying equipment and methods for transporting, handling, and depositing the concrete, as well as the rated capacity of the equipment shall be submitted for review by the Contracting Officer.

Concrete Trucks; G The make, type, capacity, and number of the concrete trucks or mixers proposed to transport concrete shall be submitted to the Contracting Officer 60 days prior to concrete placement.

SD-04 Samples

Colored Concrete;

SD-05 Design Data

Concrete Mixture Proportioning and Testing; G, DO The Contractor shall submit the results of mixture proportioning at least 60 days prior to start of concrete placement in the test section for approval.

SD-06 Test Reports

Mineral Admixtures; G,DO

Repair of Unacceptable Concrete; G,DO Within one week of detecting unacceptable concrete, as defined by the paragraph REPAIR OF UNACCEPTABLE CONCRETE, the Contractor shall prepare and submit an Unacceptable Concrete Report that includes all pertinent documentation from the construction of the failing element.

Repair of Unacceptable Concrete Plan; G, DO The Contractor shall submit a plan to repair the unacceptable concrete within 30 days of detection.

Repaired Concrete Report; G,DO The Contractor shall submit a Repaired Concrete Report detailing the repair, with test results and documentation that the concrete is acceptable within 45 days after completing the repair

Concrete Records; G,DO Detailed concrete records shall be submitted for each wall element.

Concrete Verification Cores; G,DO Concrete strength testing results from the cores.

Concrete Mixture; G,DO Tests from the point of placement including strength testing.

Concrete Records; G,DO Records placed for each element.

SECTION 03 37 29 Page 8

1.5 UNACCEPTABLE CONCRETE IN COMPLETED ELEMENTS

"Unacceptable Concrete", includes but is not limited too, concrete that is honeycombed, segregated, uncemented, under-strength, caved, containing soil or slurry intrusions, cold joints, laitance, voids, failed permeability testing, contains any anomaly greater than 2 inches, or is otherwise detrimental to the long term performance of the cutoff wall as determined by the Contracting Officer. Concrete defects are further defined in Section 31 56 10.00 08 CUTOFF WALL CONSTRUCTION. When such concrete is encountered in any element, the unacceptable concrete must be replaced or repaired in accordance the Contractor's proposal as required in paragraph REPAIR OF UNACCEPTABLE CONCRETE and as approved by the Contracting Officer.

1.6 LABORATORY TESTING FACILITIES

See Specification 03 00 00 GENERAL CONCRETE REQUIREMENTS.

1.7 GOVERNMENT TESTING AND SAMPLING

See Specification 03 00 00 GENERAL CONCRETE REQUIREMENTS.

1.8 CONCRETE FOR CUTOFF WALL CONCRETING PLAN

At least 60 days prior to the start of placement, the Contractor shall prepare a plan for review and approval by the Contracting Officer. The plan shall describe the work, equipment, and methods to be used for concrete batching, mixing, transportation, conveyance, placement, consolidation, finishing, and protection. The timing and sequence of the various steps from batching until protection shall also be described. The plan shall be sufficiently detailed to demonstrate that equipment and methods are appropriate for the specific type of concrete, and that the work conforms to project specifications. Once approved, the Contractor shall follow all procedures set forth in the plan. Any revisions to the plan shall be submitted to the Contracting Officer for approval. The sampling, transportation to validated lab, and testing shall be incidental to construction and at the contractor's expense.

The plan shall include, but not be limited to, the following items:

1) Preparation of foundation and concrete surfaces adjacent to the tremie concrete placement in accordance with Section 31 56 10.00 08 CUTOFF WALL CONSTRUCTION, paragraph CUTOFF WALL EXCAVATION.

2) Concrete production, including the equipment and procedures for batching, controlling mixing and placement temperature, and moisture control of the material constituents, and mixing speed and duration.

In addition, the plan shall include all limits and steps required to control thermal effects.

3) Transportation and conveyance of concrete from the mixer to the point of placement.

4) Methods and frequency of sampling and testing the concrete and concrete constituents.

5) Methods for placing tremie concrete, including concrete placement equipment, procedures, staging of the two types of concrete, sequence, and the method to prevent cold joints, segregation, and poor quality

SECTION 03 37 29 Page 9 concrete.

6) Methods for controlling the concrete placement temperature in hot and cold weather.

7) Methods for monitoring tremie concrete placement progress, including the sounding method, and the method for tracking tremie pipe embedment at all times during placement.

8) Protection of fresh concrete and protection through the curing period.

9) A contingency plan for dealing with unanticipated events, such as unexpected interruption to concrete placement or loss of tremie seal during concrete placement. This shall include a possible way to remove the fresh concrete from the excavation if required.

10) A contingency plan for dealing with unanticipated loss of tremie pipe or other equipment inside the excavation or concrete backfill.

1.9 TEST SECTION

A test section is required in accordance with SECTION 31 56 10.00 08 CUTOFF WALL CONSTRUCTION. The cutoff wall Test Section will demonstrate the methods, materials, and procedures to be used for the cutoff wall construction. The test section shall conform to the requirements of this section and shall meet the concrete and testing requirements described herein.

Amendment 0003**************************************************************************

1.9.1 Blasting Coordination

During the cutoff wall test section the Contractor shall determine the set time and strength gain at 2, 3, and 7 days from cylinders cast during placement in accordance with ASTM C39/C39M. These cylinders must be correlated to obtained cores tested for strength at 3 and 7 days in accordance with ASTM C39/C39M from a placed element. This information is required information to properly adjust blasting designs for green concrete in accordance with "Vibration Limits for Green Mass Concrete/Shotcrete" as required per the blasting specification sections 31 23 17.00 06 UNDERWATER BLASTING, and 31 23 18.00 06 BLASTING - SURFACE. See Specification Section 31 56 10.00 06 CUTOFF WALL CONSTRUCTION for coordination with cutoff wall concrete placement.

**************************************************************************Amendment 0003

1.10 DATA REQUIREMENTS

The Contractor and any Subcontractors performing work specified in this section must provide the data for all of the fields in the SQL database for the project pertaining to concrete for the cutoff wall as specified by the Section 01 31 00 DATA MANAGEMENT and the Volume 5 attachments. Any data requirements listed in 01 31 00 shall also apply to the data generated in the completion of the work or testing described in this section.

Ensure thorough review of the data specifications in this section, in 01 31 00 DATA MANAGEMENT, and the Volume 5 attachments, and ensure proper review and compliance by any Subcontractors.

SECTION 03 37 29 Page 10

PART 2 PRODUCTS

2.1 MATERIALS

General materials requirements are contained in Specification

03 00 00 GENERAL CONCRETE REQUIREMENTS

2.1.1 Chemical Admixtures

See SECTION 03 00 00 GENERAL CONCRETE REQUIREMENTS for general chemical admixture requirements. Admixtures used for the cutoff wall concrete may include, normal, mid-range, and high range water reducing, viscosity modifier, and anti-washout admixtures. Accelerating and retarding admixtures shall only be permitted with the approval of the Contracting Officer when justification is provided, and shall not adversely affect the quality of the concrete. Air-entrainment admixtures for cut-off wall concrete are not permitted. All admixtures shall have certification from the manufacturer.

2.1.1.1 Water-Reducing Admixtures

See SECTION 03 00 00 GENERAL CONCRETE REQUIREMENTS

2.1.1.2 Anti-Washout Admixture

2.1.1.3 Accelerating Admixture

2.1.1.4 Retarding Admixture

2.1.2 Mineral Admixtures

2.1.3 Water

2.1.4 Concrete Coloring Admixture

Pigment shall be added to the concrete to identify the interface between adjacent cutoff wall elements. Primary elements shall be uncolored and secondary panels shall be colored red and shall be compatible with all ingredients in the concrete mix. The pigment shall meet the requirements of ASTM C979/C979M. The Contractor's Concrete for Cutoff Wall Concreting Plan shall identify a required second backup color. The colors proposed by the Contractor shall provide maximum contrast when used at the manufacturer's recommended dosage. The colored concrete shall provide adequate contrast so that the color is easily observed in extracted core that has dried. Dosing shall be within the manufacturer's recommendations and shall not adversely affect the fresh or hardened properties of the concrete. The Contractor shall identify in the Concrete for Cutoff Wall Concreting Plan the colors to be used and the sequence of how the color is

SECTION 03 37 29 Page 11 to be used.

The Contractor shall prepare samples of concrete that contain the proposed coloring admixtures. The samples shall be from a test batch using the proposed mixture proportions and admixture dosage. The samples shall be cored or saw-cut to expose a cut face and shall be a minimum of 6 inches in diameter or width. Samples cut from standard 6- by 12-inch concrete cylinders are acceptable. A minimum of two batches for each color shall be submitted and a minimum of four samples from each batch of colored concrete shall be provided. Samples shall also be provided from concrete not containing any coloring admixture and shall be used for comparison to the colored concrete. The samples shall demonstrate that the colored concrete has adequate contrast at the manufacturer's recommended dosage to distinguish the concrete from other colored and uncolored concrete when placed in the cutoff wall.

2.1.5 Not Used

2.2 CONCRETE MIXTURE PROPORTIONING AND TESTING

2.2.1 Responsibility of Mixture Proportioning

The Contractor is responsible for all associated costs for development of the concrete mix design. Mixture proportioning of the Concrete for Cutoff Wall Mix is completed by the Contractor conducted in accordance with requirements provided by the Government. Once concrete mixture has been proportioned by the Contractor and approved by the Government, the mix designs are property of the Government and cannot be changed or altered without written approval from the Contracting Officer. The concrete shall comply with testing requirements provided in paragraph Concrete Mixture.

All testing shall be preformed by a laboratory approved in accordance with paragraph LABORATORY TESTING FACILITIES. The Contractor is required to insure the concrete placed for the cutoff wall complies with the contract and approved requirements.

2.2.2 Mixture Proportioning

A minimum of four concrete mix designs shall be proportioned to provide two basic types of concrete. The types of concrete shall be proportioned for underwater placement using tremie methods.

1. Type 1 concrete shall be proportioned as an underwater, flowable concrete mixture.

2. Type 2 concrete shall be proportioned as an underwater, flowable concrete mixture with an anti-washout admixture to meet the maximum washout restriction of 8.0 percent when tested in accordance with COE CRD-C 61. Additional Water Reducing Admixture or Superplasticizer shall not be added without approval from the Contracting Officer.

Re-tempering of the cutoff wall concrete with water or admixtures will not be allowed.

3. Type 1 and Type 2 above shall be proportioned with the alternative coal ash source approved by the Government from SPECIFICATION 03 00 00

GENERAL CONCRETE REQUIREMENTS.

In addition, mixture proportions shall be developed for concrete to include

SECTION 03 37 29 Page 12 coloring admixtures per this specification. The dosage shall be adequate to easily identify the color in a dry concrete core. The anti-washout concrete shall be used under the following conditions:

a. Concrete to be placed in Critical Area A and Critical Areas B1-B4 must contain an anti-washout admixture for placements with the temie pipe embedded to a depth of at least 5 feet above the top of rock (as determined by the rock elevation for the element during excavation).

See Specification 31 56 10.00 06 CUTOFF WALL CONSTRUCTION.

b. Whenever flowing conditions due to seepage or slurry loss are encountered.

c. As directed by the Contracting Officer.

The Contractor is responsible for all costs associated with the mix designs including providing samples, trial batches, QC and lab testing requirements under this section completed per the direction of the Government. Mixture proportions shall indicate the weights of cement, pozzolan, GGBFS, silica fume, and water; the weight of aggregates in a saturated surface-dry condition; the quantities of admixtures in ounces; and any other materials used. Trial mixtures having proportions, slump and slump flow, bleed, washout, set time, and air content suitable for the work shall be made in accordance with this specification. Pozzolan alone may be adequate to comply with the alkali-silica reactivity (ASR) requirements for the aggregate as set forth in the paragraph Alkali-Silica Reactivity, however, the addition of GGBFS and/or silica fume may also be necessary and may be used in combination with the pozzolan.

The record for each trial mixture shall include the proportions of each concrete constituent, the temperature of concrete, slump, slump flow, unit weight, bleed, washout, set time, and air content. If chemical admixtures are used, loss of slump and slump flow versus time shall be reported for each trial batch for a minimum time period of two hours and as required by the Contractor's means and methods. In addition, each trial mixture shall have at least three test cylinders for each test age made and cured in accordance with ASTM C192/C192M. As a minimum, the concrete shall be tested at 3, 7, 14, 28, and 90 days to demonstrate strength versus time.

Additional intermediate ages shall be tested if the Contractor is proposing to use methods where the strength or rate of strength gain is critical to the sequencing and progression of the work. The cylinders shall be made in accordance with ASTM C31/C31M and shall be tested in accordance with

ASTM C39/C39M.

The Contractor shall submit the proposed concrete mixture proportions and test results at least 60 days prior to start of the test section for approval. No substitution shall be made in the source or type of materials used in the work without additional tests to show that the quality of the new materials and concrete are satisfactory. Such required tests must be completed by the Contractor prior to resubmission of the concrete mixture proportioning submittal for approval.

Concrete Mixture Proportions shall conform to the following:

a. Compressive Strength - The concrete shall have a minimum specified compressive strength at 28 days of 2,000 psi when tested in accordance with ASTM C39/C39M. If the Contractor's methods require higher strength concrete, the required minimum specified compressive strength shall be based on the strength designated by the Contractor.

SECTION 03 37 29 Page 13

b. Permeability - The cutoff wall concrete shall provide a barrier with a permeability equal to or less than 1x10-6 cm/s. See Section 31 56 10.00 08 CUTOFF WALL CONSTRUCTION for verification testing.

c. Maximum Water-Cement Ratio - The maximum water-cement ratio by equivalent weight of portland cement in accordance with ACI 211.1 shall be 0.45.

d. Cementitious Materials Content - The concrete shall have a minimum cementitious materials content of 600 pounds per cubic yard and shall not exceed 650 pounds per cubic yard. Proportions of pozzolan, GGBFS, and silica fume shall be by equivalent absolute volume in accordance with ACI 211.1. Of the total absolute volume of cementitious materials, 75 percent shall be pozzolan. Class F Coal Ash must be between 20-30 percent, and Ground Granulated Blast Furnace Slag (GGBFS) should be between 45-55 percent.

e. Maximum-Size Coarse Aggregate - The maximum-size coarse aggregate shall be in accordance with ASTM No. 57 stone having 1-1/2 inch maximum aggregate size. The nominal maximum size shall be 1 inch.

f. Fine Aggregate - Fine Aggregate shall comprise approximately 45 to 55 percent, by volume, of the total aggregate.

g. Air Content - The air content as determine by ASTM C231/C231M shall be less than 4.0 percent.

h. Flowability - Slump and slump flow shall be between 8 to 10 inches and 16 to 24 inches, respectively. Slump shall be determined in accordance with ASTM C143/C143M, and slump flow shall be determined in accordance with ASTM C1611/C1611M (Procedure A).

i. Bleed - Bleed shall be determined by ASTM C232/C232M, Method A.

Maximum bleed shall be 3.0 percent. Bleed shall be monitored for a minimum of 8 hours due to potential delay when bleed water is released as a result of the use of chemical admixtures.

j. Unit Weight - Unit Weight shall be determined by ASTM C138/C138M for normal weight concrete.

k. Set Time (Initial and Final) - Set time shall be determined by ASTM C403/C403M. Set time shall be used to characterize the properties of the concrete for placement considerations and for the Contractor's methods and means.

l. The anti-washout concrete shall be capable of restricting the washout to a project target of less than 8.0 percent when tested in accordance with COE CRD-C 61. However, if Contractor encounters difficulties meeting the less than 8.0 percent washout requirement in high slump flow concrete mixtures, an increase in AWA dosage will be investigated and adjustments made accordingly. Contractor shall not exceed the maximum AWA dosage recommended by the manufacturer. Changes to the project target washout restriction shall not be made without justification from the Contractor and written approval of the Contracting Officer. The Contractor shall anticipate an increase in the required batching and mixing time for the production of concrete containing an anti-washout admixture. This washout restriction is only required on concrete containing the anti-washout admixture.

SECTION 03 37 29 Page 14

2.2.3 Thermal Considerations

The concrete mixture designs shall be proportioned with consideration for placement methods, placement temperature, and the sequence of placing adjacent elements to assure that thermal effects do not adversely affect the performance, integrity, and long term durability of the cutoff wall.

Semi-Adiabatic Testing is not required.

PART 3 EXECUTION

3.1 EQUIPMENT

See SECTION 03 00 00 GENERAL CONCRETE REQUIREMENTS for all batch plant equipment requirements.

3.1.1 Conveying and Placing Equipment

The conveying equipment shall have a capacity of at least 150 cubic yards per hour. Concrete shall be conveyed from batch plant to point of placement as rapidly as practicable and within the time interval specified in paragraph PLACING by methods that will prevent segregation or loss of ingredients. Any concrete transferred from one conveying device to another shall be passed through a hopper that is conical in shape and shall not be dropped vertically more than five feet, except where suitable equipment is provided to prevent segregation and where specifically approved. All equipment shall have a minimum capacity commensurate with the Contractor's proposed methods and for completion of the placement without the formation of cold joints, contamination, caving, or soil or slurry intrusion.

3.1.1.1 Concrete Trucks

3.1.1.2 Chutes

3.1.1.3 Concrete Pumps

3.1.1.4 Tremie Pipes

A funnel-shaped hopper of sufficient volume, but not less than 2 cubic yards, shall be required at the top of all tremie pipes. The hopper shall be of a size capable of receiving and passing the concrete into the pipe at the capacity rate of the batching, mixing, and conveying equipment. The tremie pipe shall be of sufficient diameter to allow the free flow of concrete, and shall have a minimum nominal internal diameter of 10 inches.

Tremie pipe shall be made of steel and have watertight joints. Aluminum pipe shall not be allowed. Hoisting equipment for lifting and lowering pipes and tools for connecting the pipe sections shall be continuously available and on hand. Each section of tremie pipe shall have threaded connections or shall have gasketed fittings. For pipe connections that are coupled and are not threaded, the coupling alone will not be considered watertight. Additional external rubber seals shall be provided around the coupling to assure a watertight connection.

The tremie pipe and hopper shall be supported by means of a platform or

SECTION 03 37 29 Page 15 bracing to hold the pipe in place while concrete is placed. Vertical movement should only occur when sections of pipe are removed to adjust the embedment depth. Means for lifting the pipe shall be stable and shall not allow the pipe to bounce. In addition, no horizontal movement of the tremie pipe will be permitted.

The end of the tremie pipe shall be equipped with a plate and gasket or other suitable watertight cap at the start of an element placement, or a commercially fabricated pipe pig/plug/go-devil shall be used. The pipe pig/plug/go-devil shall be specifically manufactured to be capable of maintaining a full seal with the walls of the tremie pipe to the depth of the concrete placement. The plug shall be rated by the manufacturer so that it does not compress and lose the seal before the pig/plug/go-devil reaches the end of the pipe. The watertight cap shall be secured to the bottom of the tremie pipe or the pig/plug/go-devil shall be positioned in the entrance of the pipe before concrete is placed in the tremie pipe, and the pipe shall be lowered and put in contact with the bottom of the placement. The pig/plug/go-devil shall have sufficient buoyancy to float in concrete. The pipe and hopper shall be fully charged, then the pipe shall be raised 6 to 12 inches to initiate the flow of concrete. Additional concrete shall be ready at the point of placement to allow a continuous flow of concrete down the pipe.

Alternatively, as part of the concrete cutoff wall work plan, the Contractor may propose to use a dynamic start technique. Should this technique be proposed the Contractor shall submit all required equipment along with a detailed step by step description of the process. In addition a list of past projects where the technique was demonstrated successful shall also be provided. The technique would be required to be demonstrated in the test section and evaluated through applicable coring, permeability tests, etc.

3.2 PREPARATION OF EXCAVATION

Preparation of the excavation prior to concrete placement shall be made in accordance with Section 31 56 10.00 08 CUTOFF WALL CONSTRUCTION. The bottom of the element excavation shall be cleaned and sounded prior to placement of concrete backfill. In addition, the vertical face of previously placed concrete adjacent to the element to be placed shall be clean.

3.3 PLACING

3.3.1 Concrete Superintendent

The Concrete Superintendent for cutoff walls may be a different individual than the concrete superintendent for outlet works construction. The concrete superintendent for cutoff walls must also have at least 5 years of experience placing mass concrete below water using tremie methods.

See SECTION 03 00 00 GENERAL CONCRETE REQUIREMENTS for other Concrete Superintendent requirements.

3.3.2 Time Interval Between Mixing and Placing

Concrete shall be delivered to the site of the work, and the placement shall be completed within 60 minutes after introduction of the cement to the mixing water or aggregates. When a truck mixer or agitator is used for transporting concrete, the concrete shall be placed within 30 minutes after

SECTION 03 37 29 Page 16 mixing or agitating ceases.

3.3.3 Placing Temperature

Concrete, when deposited in the slurry, shall have a temperature of not less than 45 degrees F. Heating of the mixing water or aggregates shall not be permitted until the temperature of the concrete has decreased to 50 degrees F. The materials shall be free from ice, snow, and frozen lumps before entering the mixer. All equipment and methods used to control the placement temperatures shall be subject to approval. When heating is necessary to keep the concrete temperature above 45 degrees F, it shall be regulated so that the concrete temperature does not exceed 60 degrees F.

Otherwise the concrete, when deposited in the slurry, shall not exceed 80 degrees F. Cooling of the mixing water and/or aggregates may be required to obtain an adequate placing temperature. Depending on the Contractor's methods of construction, additional temperature restrictions may be necessary. The Contractor is responsible for assuring thermal effects and cracking do not adversely affect the required performance of the cutoff wall.

3.3.5 Concrete Placement

3.3.5.1 General

Concrete mixes shall be required at the locations as described in Section

31 56 10.00 08 CUTOFF WALL CONSTRUCTION.

All concrete shall be placed through a tremie pipe during concrete placement regardless of the Contractor's means and methods. The methods and equipment used shall be subject to approval. Concrete placement will not be permitted when, in the opinion of the Contracting Officer, weather conditions prevent proper placement. The system used to deliver concrete to the tremie pipe shall not allow any vertical drop greater than five feet except where suitable equipment is provided to prevent segregation and where specifically authorized.

Placement method shall be capable of delivering concrete to the tremie pipe in a continuous supply that will not cause segregation or honeycombing of concrete aggregates. No lift or cold joints shall be allowed to develop.

Intermediate transfer hoppers shall be used if necessary when concrete delivery methods do not assure a continuous and uniform supply. The tremie pipe shall be watertight and sufficiently large to permit a free flow of concrete. Tremie pipe sections shall be suitably secured together and a gasket used at each joint to prevent leakage. A dry pipe with a plate and gasket wired to the bottom of the pipe shall be used to prevent contact of the concrete in the tremie pipe with the slurry. This device shall be required to start each placement. The device shall be submitted to the Contracting Officer for approval before concrete production starts.

A funnel-shaped hopper of at least two cubic yards in volume shall be required at the top of each tremie pipe. The tremie pipe shall be fully supported during concrete placement so that the pipe does not move vertically or laterally. Equipment for hoisting the pipe shall provide smooth vertical movement without bouncing the pipe or allowing lateral movement. Under these conditions, the Contractor shall describe details of concrete placement methods in the Concrete for Cutoff Wall Concreting Plan. Neither the tremie pipe nor the hopper shall be constructed of aluminum. Hoisting equipment for raising and lowering the tremie pipe as

SECTION 03 37 29 Page 17 the concrete is placed and tools for connecting the tremie pipe sections shall be continuously available and on hand.

No concrete shall be placed in a wall element excavation unless the Contracting Officer's Representative (COR) is present. The COR will reject an element if it fails to meet strength or permeability requirements, or if in the opinion of the COR, the long term durability of the element has been compromised as described in paragraph REPAIR OF UNACCEPTABLE CONCRETE.

The requirements for tremie concrete shall be tested at the point of placement and shall be in compliance with the specifications. The Contractor shall be responsible for all the necessary field adjustments of the mixture to account for various field factors such as changes in moisture content of the aggregates or ambient temperatures. All field adjustments to the concrete mixture shall be recorded and the records shall be submitted to the Contracting Officer.

Pigment meeting the requirements of ASTM C979/C979M shall be added to the concrete. Primary elements shall be uncolored and secondary panels shall be colored red and shall be compatible with all ingredients in the concrete mix. The Contractor's Concrete for Cutoff Wall Concreting Plan shall identify a required second backup color. The colors proposed by the Contractor shall provide maximum contrast when used at the manufacturer's recommended dosage and shall be adequate to identify the contact area between adjacent cutoff wall elements so that the color is easily observed in extracted core that has dried. Dosing shall be within the manufacturer's recommendations and shall not adversely affect the fresh or hardened properties of the concrete. The field notes for each panel and the As-Built drawings shall note which panels contained colored concrete.

3.3.5.2 Placement Initiation

Before concrete is placed, the excavation shall be prepared in accordance with Section 31 56 10.00 08 CUTOFF WALL CONSTRUCTION. The Contracting Officer's Representative and the designated Contractor Quality Control representative shall sign off that the excavation has been properly prepared and is ready to receive concrete. Regardless of the methods for conveying the concrete to the tremie hopper, the concrete shall be delivered as a continuous supply of concrete. An adequate supply of concrete shall be available before a placement begins to fully charge the tremie pipes and hoppers. Additional concrete shall be ready at the point of placement to allow a continuous flow of concrete down the tremie pipe, and to immediately provide adequate concrete to establish pipe embedment in the element concrete. The tremie pipe shall not be raised after the flow is started, unless the end of the pipe remains embedded at least 10 feet into the previously placed concrete. The tremie pipe shall only be raised vertically and shall not be moved horizontally for any reason. The methods used to place concrete shall be suitable to prevent the tremie pipe and placement methods from dislodging any material from the excavation sidewalls. The tremie pipe shall be placed in the center of each single-bite element. A sufficient number of tremie pipes shall be used in multi-bite elements so the concrete does not flow horizontally a distance of more than 8 feet from a tremie pipe; i.e., tremie pipes shall be placed a maximum of 15 feet on centers. If multiple tremie pipes are used, a separate truck or other delivery system shall be present and discharging concurrently for each tremie pipe utilized. When more than one tremie pipe is used in the same placement, the depth of concrete at each pipe position shall be maintained nearly level with respect to the other, and each tremie

SECTION 03 37 29 Page 18 pipe hopper shall be charged concurrently to create a uniform placement and to minimize the concrete flow distance.

3.3.5.3 Placement

Concrete placements shall proceed following the initial placement described in the paragraph Placement Initiation. In addition, concrete with the anti-washout admixtures shall be used whenever flowing conditions due to seepage or slurry loss are encountered, or as directed by the Contracting Officer.

Batches of concrete shall be supplied to the tremie pipe at a uniform rate for a continuous flow through the full depth of the element. No lift or cold joints shall be allowed to develop. The tremie pipe shall be lifted during the placement at a rate that will maintain at least 10 feet of embedment between the end of the pipe and the previously placed concrete and shall produce a uniform rate of flow and a shallow surface slope at the top of the concrete placement. Repeated raising and lowering of the tremie pipe within the fresh concrete to facilitate placement shall be minimized.

It may be necessary to reduce the amount of embedment as the differential head decreases between the concrete in the tremie pipe and the concrete in the element. However, the minimum embedment of 10 feet shall be maintained.

Should tremie embedment be lost, the Contracting Officer may require the Contractor to remove all the concrete from the excavation, restore and retest the slurry, resound the element excavation, and start the concrete placement over completely. The Contractor shall have a method to quickly remove concrete from an excavation if tremie embedment is lost and the Contracting Officer requires the complete removal of the concrete.

Otherwise, if the Contracting Officer allows the placement to resume, the tremie pipe shall be fully withdrawn, a steel plate and gasket or other approved watertight cap shall be placed over the end of the pipe. The pipe shall be reset into the concrete a minimum depth of 10 feet, and the flow of concrete shall be re-established. As soon as practical, the Contractor shall drill a HQ-size core boring through the center of the cutoff wall to verify that the concrete is of uniform quality and meets the requirements for the cutoff wall. The boring shall be made at the Contractor's expense and shall be taken to a depth of at least 5 feet below the depth where the minimum embedment was lost and the tremie pipe was lifted out of the fresh

Placement shall proceed without interruption until the concrete has been brought to the required elevation. The Contractor shall continuously measure and record the flow and slopes during placement with the use of a sounding line. The placement shall continue until the required elevation in accordance with paragraph Required Height of Concrete.

3.3.6 Required Height of Concrete

Good quality concrete meeting concrete specifications shall be placed to the required elevation shown on the drawings. The concrete shall be over placed as necessary to achieve a level surface across the entire element and to remove all laitance, scum, slurry, washed out concrete, contaminants, or otherwise poor quality concrete from the top of the concrete as the placement is nearing completion.