Am__0001.pdf

AMENDMENT 0001 CONTINUATION PAGE

The proposal due date has changed. A proposal due date of 2:00pm CST, 28 November 2012 is hereby established. Additionally, the deadline to submit questions has been extended to 2:00pm CST, 21 November 2012.

Cover Letter

In subject line, removed Solicitation Number WBV082-11-H-0011, and replace with WBV082- 11-H-0022.

Offeror Questions and Answers

1) In the TFP/TRS Paragraph it mentions that no gaps shall be permitted, but it also mentions that at the direction of the contracting officer, the gap closure shall be executed. I don’t see anything else that mentions gap closure and I am not sure when this would be applicable.

RESPONSE TO Q1: The last sentence of Para. 18, "TEMPORARY FLOOD PROTECTION", Spec Section 01100 (At the direction of the Contracting Officer, the gap closure shall be executed.) will be deleted since there will be no gaps in the TRS/TFP. Deletion of this requirement/sentence will be within an forthcoming amendment.

2) Since the TRS is government designed, does the material become the property of the government. Does the material have to be new material with certifications?

RESPONSE TO Q2: All material for the TRS/TFP will become property of the contractor upon completion of the project. Material certifications are required for review and approval of new or used material. It will be up to the Contractor on whether new or existing material is used for Construction. Used material must be in good condition and structurally adequate to perform as TFP. Requirements for use of existing sheets will be added to an forthcoming modification.

3) Why do shop drawings have to be submitted on the TRS if it has already been designed by the Government?

RESPONSE TO Q3: Shop drawings are required to provide the actual sheet pile layout, including accommodation of Contractor means and methods and any associated changes, especially at tie-ins, corners, and other areas of interest.

SECTION 01100

Page 21, paragraph 18. Delete the last sentence in its entirety.

SUBMITTAL REGISTER

Add the attached Submittal Register in addition to the current Submittal Register.

NEW SECTION 31 32 13 01.12

Add the attached new Section 31 32 13 01.12.

SECTION 31 41 16.00 12

Page 5, paragraph 1.6. Add the following publication to the listing as:

“THE SOCIETY FOR PROTECTIVE COATINGS (SSPC)/ NATIONAL

ASSOCIATION OF CORROSION ENGINEERS (NACE)

SSPC-SP 10/NACE No. 2 (2000) Near-White Blast Cleaning”

Add the following new paragraph after paragraph 2.4.

“2.5 USED STEEL SHEET PILING

Steel for sheet piling shall conform to the requirements of ASTM A 328/A 328M. Sheet piling, including special fabricated sections, shall have the properties equivalent to those listed in paragraph “STEEL SHEET PILING”, at minimum and be of a design such that when in place they will be continuously interlocked throughout their entire length. Any PZ or PZC shape piling is acceptable. However, no more than 3 types of sections are permitted across the entire project and the sheet pile section shall be consistent within the reach. All sheet piling shall be provided with standard pulling holes located approximately 4 inches below the top of the pile, unless otherwise shown or directed. Steel sheet piling shall be hot rolled. The minimum thickness shall be 5/16-inch. Used sheets shall be cleaned to a SSPC-SP 10/NACE

No. 2 Near White Finish and then visually inspected for corrosion, damage, warping, bowing, etc. that would affect the installation and operability of the sheet pile wall. Thickness checks shall also be performed on 25% of the sheets randomly selected using ultrasonic methods or by direct measurement using calipers. Measurements shall be done 5-foot from the top and bottom and one at the approximate center. The pilings and measurement locations shall be selected by the Contracting Officer. In addition to the 5/16-inch minimum thickness, an occasional maximum 1/8-inch pitting is permitted provided the net section thickness at the pitting location is a minimum of ¼-inch.”

DRAWINGS

SHEET IDENTIFICATION No. S-106. Delete this drawing in its entirety and substitute the attached revised drawing SHEET IDENTIFICATION Nos. S-106 therefore.

SUBMITTAL FORM,Jan 96 PREVIOUS EDITION IS OBSOLETE PAGE 1 OF 1 PAGES

WBV-82 Gulf South Pipeline Utility Crossing

31 32 13.01 12 SD-01 Preconstruction Submittals 1.6Experience Profile 1.6Experience and/or Training

Records 1.10Jet Grouting Work Plan 1.11Sample Log 1.8Quality Assurance-Quality

Control Program Plan 1.8Test Means and Methods

SD-02 Shop Drawings 1.8Jet Grouting 3.1.2Jet Grouting

SD-03 Product Data 3.1.3Design Mix

SD-06 Test Reports 2.2.5Metering Equipment 3.3.2As-Built Field Measurement Data

SUBMITTAL REGISTER

CONTRACT NO.

TITLE AND LOCATION CONTRACTOR

CONTRACTOR:

SCHEDULE DATES

CONTRACTOR

ACTION

APPROVING AUTHORITY

A C T I V I T Y

N O

T R A N S M I T T A L

N O

S P E C

S E C T

DESCRIPTION

ITEM SUBMITTED

P A R A G R A P H

C L A S S I F I C A T I O N

G O V T

O R

A E

R E V W

R SUBMIT

APPROVAL

NEEDED

BY

MATERIAL

NEEDED

BY

A C T I O N

C O D E

DATE

OF

ACTION

DATE FWD

TO APPR

AUTH/

DATE RCD

FROM

CONTR

DATE FWD

TO OTHER

REVIEWER

DATE RCD

FROM OTH

REVIEWER

A C T I O N

C O D E

DATE

OF

ACTION

MAILED

TO

CONTR/

DATE RCD

FRM APPR

AUTH REMARKS

(a) (b) (c) (d) (e) (f) (g) (h) (i) (j) (k) (l) (m) (n) (o) (p) (q) (r)

Am_0001_WBV-82, Gulf South Pipeline Utility Crossing Ed 12-067

SECTION TABLE OF CONTENTS

DIVISION 31 - EARTHWORK

SECTION 31 32 13 01.12

JET GROUTING

PART 1 GENERAL

1.1 SCOPE

1.1.1 Definitions

1.2 REFERENCES

1.3 SUBMITTALS

1.4 MEASUREMENT AND PAYMENT

1.5 PERFORMANCE REQUIREMENTS

1.6 EXPERIENCE PROFILE

1.7 QUALITY CONTROL

1.8 GENERAL, JET GROUTING

1.9 Reporting

1.10 JET GROUTING WORK PLAN

1.11 SAMPLE LOG

1.12 DELIVERY, STORAGE, AND HANDLING OF MATERIALS

1.12.1 Storage of Binder

1.13 JOB CONDITIONS

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 Grout

2.1.2 Cement

2.1.3 Admixtures

2.1.4 Bentonite

2.1.5 Water

2.2 GENERAL EQUIPMENT REQUIREMENTS

2.2.1 Drilling Equipment

2.2.2 Jet Grouting Monitors

2.2.3 Grout Mixing and Injection Equipment

2.2.4 Jet Pumps

2.2.5 Metering Equipment

2.2.6 Spare Parts

PART 3 EXECUTION

3.1 General

3.1.1 Damaged Holes

3.1.2 Jet Grouting

3.1.3 Design Mix

3.1.4 Equipment

3.2 TEST PROGRAM

3.2.1 Test Section Geometrics

3.2.2 Modifications

3.3 INSTALLATION OF JET GROUT COLUMNS/PANELS

3.3.1 Deviations

SECTION 31 32 13.01 12 Page 1 ED 12-067

3.3.2 As-Built Field Measurement Data

3.4 ACCEPTANCE CRITERIA

3.4.1 Remedial Measures

3.5 COLLECTION AND DISPOSAL OF WASTE SLURRY RESULTING FROM JET GROUTING

OPERATIONS

3.5.1 Stockpiles

3.5.2 Disposal of Debris and Containment for Grout Spoils

3.6 PREVENTION OF GROUND HEAVE

-- End of Section Table of Contents --

SECTION 31 32 13.01 12 Page 2 ED 12-067

SECTION 31 32 13 01.12

JET GROUTING

PART 1 GENERAL

1.1 SCOPE

The work covered by this section includes the Contractor furnishing all labor, equipment, and materials necessary for installing ground water cut-off walls utilizing jet grouting and all associated testing, monitoring, sampling and recording required for installing the jet grouting for required temporary retaining structures/temporary flood protection (TRS/TFP)shown on the drawings as specified herein. The Contractor shall submit for approval to the Contracting Officer a Jet Grouting Plan, including a plan for execution of the work and all supporting data or calculations to support the plan. Locations for the proposed jet grouting colums are shown on the drawings.

1.1.1 Definitions

1. Monitor: A tool designed to convey the elements of the jet grouting process: air, water and/or grout. The monitor has one or more injection points. The cutting action of the erosion jet(s) is enhanced by surrounding it within a concentric collar of compressed air (double and triple fluid systems).

2. Jet Grouting: The process of creating stabilized soil-cement columns in place utilizing a grout mix delivered at high pressure through a special drill bit that has high velocity horizontal jets.

This process produces soil-cement columns by pumping a neat cement grout slurry through horizontal jets which cuts and mixes in-situ with the surrounding soil materials as the drill bit is slowly rotated and withdrawn.

3. Primary Columns: Jet grout columns constructed into soft subgrade soils to provide stability of the new levee.

4. Secondary Columns: Jet grout columns constructed between and overlapping with the primary columns to tie into the adjacent primary columns providing a continuous panel as outlined on the contract drawings.

1.2 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.

AMERICAN PETROLEUM INSTITUTE (API)

API 13A (2010) Specification for Drilling-Fluid Materials

SECTION 31 32 13.01 12 Page 3 ED 12-067

ASTM INTERNATIONAL (ASTM)

ASTM C 150 (2009) Standard Specification for Portland Cement

ASTM C 494 (2008a) Standard Specification for Chemical Admixtures for Concrete

ASTM C 989 (2009a) Standard Specification for Ground Granulated Blast-Furnace Slag for Use in Concrete and Mortars

ASTM D 1633 (2000; R 2007) Compressive Strength of Molded Soil-Cement Cylinders

ASTM D 2113 (2008) Rock Core Drilling and Sampling of Rock for Site Investigation

ASTM D 2166 (2006) Standard Test Method for Unconfined Compressive Strength of Cohesive Soil

ASTM D 2850 (2007) Standard Test Method for Unconsolidated-Undrained Triaxial Compression Test on Cohesive Soils

ASTM D 4138 (2007a) Standard Practices for Measurement of Dry Film Thickness of Protective Coating Systems by Destructive Cross-Sectioning Means

ASTM D 4380 (1984; R 2006) Standard Test Method for Density of Bentonitic Slurries

ASTM D 5079 (2008) Preserving and Transporting Rock Core Samples

ASTM D 5084 (2003) Measurement of Hydraulic Conductivity of Saturated Porous Materials Using a Flexible Wall Permeameter

1.3 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submittals shall be reviewed and stamped by a licensed professional engineer except for survey data which shall be stamped by a licensed professional engineer or registered land surveyor. Engineer should be licensed in the State of Louisiana. The following shall be submitted in accordance with Section

01 33 00 SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Experience Profile

The Contractor shall acquire from the jet grouting installera detailed experience profile showing that he/she is experienced and competent to construct a jet grout columns within low head areas.

SECTION 31 32 13.01 12 Page 4 ED 12-067

The jet grouting company shall have at least five years of prior experience performing similar projects.

Experience and/or Training Records

Experience and/or training records of operators of jet grouting equipment and of on-site supervision of the Contractor's operations. The experience shall be specific to the type of grouting method being utilized by the Contractor for this contract.

Jet Grouting Work Plan

Submit a detailed Jet Grouting Work Plan describing the proposed grouting methods and equipment to be used.

Sample Log

Quality Assurance-Quality Control Program Plan

A description of the Quality Assurance-Quality Control Program Plan including:

Example formats of Daily Production Reports meeting the requirements stated herein.

Test Means and Methods

Details of all test means and methods proposed by the Contractor to verify that columns meet the specified compressive strength and permeability requirements.

Written verification that the firm experienced with jet grouting has an established record of at least five years experience in performing similar jet grouting operations. The core drill operator shall have at least two years experience coring jet grout or soil cement mixture. The work will not commenceuntil the Contractor and the operator have been approved.

Written verification that an experienced, full-time supervisor and jet grout drill rig operator, who has been in responsible charge of supervising jet grouting operations for at least two years. The supervisor shall be present at the work site at all times during jet grouting operations.

Written verification of the experience records of jet grouting firm and supervisor. Submit documentation of experience for approval prior to beginning jet grouting. Jet grouting operations shall not begin until the jet grouting firm and supervisor have been approved by the Contracting Officer.

SD-02 Shop Drawings

Jet Grouting

Submit shop drawings including sequence, time schedule of the jet grouting operations. Drawing locations of the jet grouting shall be shown on a drawing not smaller than 1 inch = 10 feet scale to show the details of the layout required to satisfy the geometries required. The drawings shall include the following:

SECTION 31 32 13.01 12 Page 5 ED 12-067

1. Plant, equipment, and material descriptions.

2. Arrangement of grout mixing and injection equipment, location of boreholes, and other necessary details.

3. Methods for drilling and supporting boreholes.

4. Sequence of soilcrete installation.

5. Grout mix design, sources of mix materials, and material data demonstrating compliance with the specified mix material described herein.

6. Layout and procedures for test program to establish jet grouting parameters, including sampling and testing to determine quality and properties of grout materials.

SD-03 Product Data

Description of method(s) and equipment to be used to penetrate the existing ground conditions and to install the grouting.

Include details and catalog-cut sheets and all ancillary equipment.

Design Mix

At least 2 weeks prior to construction, the Contractor shall submit proportions and properties of his proposed design mix including cement, bentonite, additives, and water proportions;

viscosity, density, unconfined compressive strength, and permeability to the Contracting Officer for review and approval.

Either a new project-specific laboratory design mix program or the results of previous laboratory test programs (as long as the materials are similar to those proposed for construction) are acceptable.

SD-06 Test Reports

Metering Equipment

Calibration test results for metering equipment.

As-Built Field Measurement Data

A log of the installation of each column shall be prepared by the Contractor and submitted to the Contracting Officer within one day of installation. The log shall contain the information listed herein.

1.4 MEASUREMENT AND PAYMENT

No separate measurement and payment will be made for jet grouting, as specified. All costs in connection therewith shall be included in the contract lump sum contract price for "Temporary Retaining Structures/Temporary Flood Protection".

1.5 PERFORMANCE REQUIREMENTS

The Contractor shall install jet grout columns at the locations and configurations in the areas shown on the drawings and specified herein, meeting the acceptance criteria defined in paragraph "Acceptance Criteria".

SECTION 31 32 13.01 12 Page 6 ED 12-067

1.6 EXPERIENCE PROFILE

The Contractor shall have an established record of at least five years experience in performing similar jet grouting operations including a successful cut-off wall installation with the same equipment as proposed.

The Contractor shall not commence work until the Contracting Officer has approved the jet grouting company, it's supervisor, and the Jet Grouting Plan. The Contractor shall acquire an experienced full-time supervisor who has been in responsible charge of supervising jet grouting operations for at least two years. The jet grouting supervisor shall be present at the work site at all times during jet grouting operations. The Contractor shall provide detailed information on the training and experience of any jet grout rig operators with less than 5 years experience for approval by the Contracting Officer; but in no case shall any operator have less than 2 years of experience in the installation of deep mixed jet grout cut-off walls. The Contractor shall also provide a site superintendent and/or site engineer with a minimum of 2 years experience in deep mixed jet grout cut-off wall installation. The core drill operator shall have at least two years experience coring jet grout or soil cement mixtures. The Contractor shall provide verification of the experience records of jet grouting and supervisor. The contractor shall submit documentation of experience and/or training records for approval prior to beginning jet grouting.

1.7 QUALITY CONTROL

The Contractor shall establish and maintain quality control to confirm the jet grout columns are installed in accordance with submittals, and achieve the specified performance requirements to ensure compliance with contract specifications and maintain records of his quality control for all construction operations.

1.8 GENERAL, JET GROUTING

The Contractor shall implement a Quality Assurance-Quality Control Program Plan to permit the confirmation that the ground treatment methods performed are applied in accordance with this specification, approved submittals, sampling and testing, and have achieved the specified Acceptance Criteria.

The QC Plan shall also be implemented to generate and maintain records of the quality control measures for construction operations including, but not limited to, the following:

a. Equipment. Type, size, and suitability for the construction of the prescribed work.

b. Materials. Compliance with this specification and approved submittals.

c. Installation.

1) Continuous injection, mixing vertically full depth, with computer monitoring.

2) Geometric Tolerances. Horizontal alignment of the elements shall be within 2 inches of the planned location as measured at the ground surface. The horizontal overlap between primary and secondary elements and the mixing shaft overlap within primary elements for multi-shaft rigs shall be as shown on the plans. The inclination of the columns (vertical alignment) shall be within

1.0 percent of vertical as measured at the ground surface.

SECTION 31 32 13.01 12 Page 7 ED 12-067

3) The width of the shear panels shall be within ±1 percent of the shear panel width shown in the plans.

4) Top of shear panels shall be at least the top elevation shown in the plans.

5) Bottom of shear panels shall be no higher than the bottom elevation shown in the plans.

d. Sampling and Contractor Test Means and Methods

1) Tests. Unconfined compression tests and permeability shall be performed for core and wet grab samples. Unconfined compression testing shall be performed in accordance with ASTM D 2166.

Permeability tests shall be performed in accordance with

ASTM D 5084.

2) Coring. Three percent of the total installed elements shall be cored and tested. Additional coring may be done at the discretion of the Contracting Officers' Representative, if significant deficiencies are found based on the planned testing.

The Contracting Officer will select the elements to be cored.

Contractor shall perform core sampling of hardened soil-cement, in accordance with ASTM D 2113. The core shall be obtained for the full depth of the element. The minimum core recovery shall be 80 percent. Core samples intended for strength tests should be prepared in accordance with the "Special Care" requirements of ASTM D 5079, Section 7.5.2, and stored in a moist room or other curing facility. If recovery is lower than required, the Contracting Officer may require additional coring at Contractor's expense. The cores shall be made available for review by the Contracting Officer. Contractor shall determine the core recovery for each core run. For core sampling, the sample diameter shall be at least 3.0 inches or greater and core runs shall be no more than 5 feet. Contractor shall grout each core hole with neat cement grout (water cement ratio 1:1) at the completion of each core hole using tremie methods.

3) The Contracting Officer shall select 10 core samples from each coring location for strength testing. The test specimens shall have a length to diameter ratio of 2. Unconfined compression tests shall be performed on each core sample at approximately 28 days after column installation.

4) Wet Grab Samples. No less than two samples per 100 feet of installed column or panel.

e. Specific Gravity

The specific gravity of the grout shall be determined during the validation program for double-checking grout proportions.

Contractor shall check the specific gravity of the grout at least twice per shift per rig using the methods outlined in ASTM D 4380.

The specific gravity measurements shall be indicated on the Daily Quality Control (QC) Report.

f. Other Contractor Proposed Testing

SECTION 31 32 13.01 12 Page 8 ED 12-067

The Contractor may propose other types of tests, or exploration to evaluate quality of the completed elements. Such tests may include down-hole video inspection, sonic testing, Menard Pressure-meter tests, or others. All other contractor proposed testing shall be subject to approval of the Contracting Officer.

1.9 Reporting

The original and two copies of QC testing records, as well as the records of corrective action taken, shall be furnished the Contracting Officer's Representative daily. Format of report shall be as specified in Section

01 45 04.00 10 CONTRACTOR QUALITY CONTROL.

1.10 JET GROUTING WORK PLAN

Submit a detailed Jet Grouting Work Plan describing the proposed grouting methods and equipment to be used. At a minimum the Jet Grouting Work Plan shall include:

a. Jet grouting procedures for supporting the interceptor, fills and for groundwater control at the shift excavations.

b. Provisions to prevent discharge of slurry grout outside of the rights-of-way limits, including potential hydrofracture or inadvertant returns and provisions to contain any discharge and mitigate future grout losses, should it occur.

c. Description of grout plant and equipment.

d. Arrangement of grout mixing, recording, and injection equipment, layout of grout columns, and other details to illustrate the plan for setting up each site to be treated.

e. Schedule and sequence for competing jet grouting test columns and production jet grouting work.

f. Layout and designation of jet grout columns for shaft excavations.

g. Layout and designations of jet grout columns.

h. Grout mix design, sources of mix materials, and admixtures.

Grout mix design shall include target range for unit weight, marsh viscosity, and bleed, that will produce desired grout strength.

Provide 7 and 28 day design compressive strengths for neat cement grout mix. Submit MSDS sheets for admixtures that may be used.

i. Quality control procedures including record keeping, field testing, sampling, and laboratory testing of completed columns.

j. Grout mix proportions, design, sources of mix materials, and material data, including a daily record of batch quantities and cement dosages and a daily record of spoil handling quantities and weight of spoil disposal. The Contractor shall submit calculations demonstrating a maximum insitu diluted water to cement ratio to be accomplished by the mix design and jetting parameters, and a plan to demonstrate insitu water to cement effectiveness by material balance or other means.

SECTION 31 32 13.01 12 Page 9 ED 12-067

k. Layout and procedures for test program to establish jet grouting parameters, including sampling and testing to determine quality and properties of grout materials.

1.11 SAMPLE LOG

Sample logs shall include:

a. Project name.

b. Machine number.

c. Type of grouting tool.

d. Date and time of the jet grouting installation .

e. Plant, equipment and material descriptions.

f. Arrangement of grout mixing and injection equipment, location of boreholes, and other necessary details.

g. Methods for drilling and supporting boreholes.

h. Sequence of grouting installation.

i. Grout mix proportions.

j. Grout hole geometry (size, length and location).

k. Time and date of beginning and completion of each grout column.

l. Erosion jet pressures used to construct each grout element.

m. Grout rates and takes for each grout column.

n. Rates of rotation and withdrawal of jet grout monitor for each grout element.

o. Other pertinent observations, such as: grout escapes, ground heave, or other unusual behavior.

p. A description of obstructions or other interruptions of binder injections during installation.

1.12 DELIVERY, STORAGE, AND HANDLING OF MATERIALS

Deliver all materials in undamaged, unopened containers bearing manufacturer's original label. The Contractor shall store, measure, handle, transport, and store bulk cement in accordance with the manufacturer's recommendations. Cement shall be stored to prevent damage by moisture.

Material which has become caked due to moisture absorption shall not be used. Cement containing lumps or foreign matter of a nature and in amounts that may be deleterious to the injection operations shall not be used.

1.12.1 Storage of Binder

Binder shall be stored and delivered to the mixing points in closed pressure tanks suitable to be used as pressure vessels, for all pressures required including those used to load and unload the materials.

SECTION 31 32 13.01 12 Page 10 ED 12-067

1.13 JOB CONDITIONS

The Contractor shall familiarize himself with job site geotechnical and hydrological conditions and recognize that amongst others, the silts and clays have variable and often high moisture contents, and variable and often high organic contents. Boring logs are included in the plans.

Throughout execution of the work, the Contractor shall take all precautions and measures necessary to safely move and position equipment, support equipment and personnel around the site. It is anticipated that jet grouting may be preformed simultaneously with other activities associated with this contract. Prior to the jet grouting, the Contractor's site preparation work will have produced a suitable working surface for the equipment. The Contractor shall provide equipment, materials, cribbing timber mats or other support structures necessary to provide a stable-working surface for the jet grouting. Granular fill may not be used without prior acceptance of the Contracting Officer. The Contractor shall evaluate and analyze the jet grouting based on the Contractor's proposed construction sequence and methods. The Contractor shall perform all jet grouting work with qualified personnel under the continuous supervision of the jet grouting supervisor approved by the Contracting Officer.

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 Grout

Grout shall be a mixture of Portland cement, water and bentonite or other non-toxic, biodegradable admixtures if required. The grout shall be mixed in a grout plant that combines dry cement and water in predetermined proportions. Grout mixes shall have a consistency that is fluid and pumpable. Grout mixes shall be proportioned to provide the required strength and mixing consistency. The grout mix utilized shall have a maximum water/cement ratio of 1:1 by weight.

2.1.2 Cement

ASTM C 150 Portland Type I or Type I-II and/or ASTM C 989 Ground Granular Blast Furnace Slag Grade 120 or a mixture of both.

2.1.3 Admixtures

Cement admixtures will not be allowed, without prior submittal showing effect and acceptance of the Contracting Officer. Common water treatment additives may be used to correct water quality or enhance bentonite hydration and mixing. These additives may include soda ash, lime, or alum.

Admixtures of softening agents, dispersants, retarders, or plugging or bridging agents may be added to the water or the slurry to permit efficient use of bentonite and proper workability of the cement bentonite slurry.

Retarders, thinners, and accelerators may be used under the direct supervision of the Contractor to correct specific problems. Peptizing or bulking agents will not be permitted for mixing with slurry. When admixtures are used to improve pumpability, to control set time, and to prevent segregation and bleeding, admixtures shall be non-toxic and biodegradable and conform to ASTM C 494.

SECTION 31 32 13.01 12 Page 11 ED 12-067

2.1.4 Bentonite

Premium grade, ultrafine, sodium cation based montmorillonite powder (Wyoming type bentonite) that meets or exceeds the requirements of API 13A.

Grout mix shall not contain more than 2 percent bentonite, by dry weight of cement or as approved by the Contracting Officer.

2.1.5 Water

Fresh and potable water shall be used.

2.2 GENERAL EQUIPMENT REQUIREMENTS

All equipment used for drilling boreholes; lowering, raising and rotating jet monitors, mixing grout, supplying pressurized grout and air-water to jet monitors, and jet monitors used to perform the deep mixing shall have proven performance records for use in jet grouting work. Spare parts and equipment shall be available on site to maintain jet grouting equipment in satisfactory operation condition at all times during execution of the jet grouting work.

2.2.1 Drilling Equipment

Use drilling equipment of a type and capacity suitable for drilling required hole sizes and depths, and lowering, raising, and rotating jet grout monitors to the depths and at the rates required to perform the cut-off wall installation for the full range of subsurface conditions described in the geotechnical boring logs, shown on the Contract Drawings and as specified herein.

2.2.2 Jet Grouting Monitors

Use jet grouting monitors as described in herein having capacity suitable for producing grout elements in the work site soil types identified in the Geotechnical Reports, and of the size and depth shown on the Contract Drawings and as specified herein.

2.2.3 Grout Mixing and Injection Equipment

Use high-speed colloidal shear grout mixer, grout agitator, automatic electronic control unit, and holding tanks, water tanks, air compressors, and pumps of sufficient capacity to ensure adequate supply of grout, air, and water at required pressure to the jet grouting monitors during a full work shift to produce grout columns of the quality and dimensions necessary.

2.2.4 Jet Pumps

Pumps shall be high-pressure pumps capable of delivering the grout at the flow rates and pressures required.

2.2.5 Metering Equipment

Provide automatic recording equipment with a meter to determine the volume of grout injected. The meter shall be calibrated within the past two months in liters to the nearest liter. The grout injection rate recorded by flow meter shall be verified daily by counting the strokes of the piston pump in a fixed period of time and recorded on grout logs.

SECTION 31 32 13.01 12 Page 12 ED 12-067

2.2.6 Spare Parts

Spare parts and/or equipment shall be available on site to maintain the jet grouting equipment in satisfactorily operating conditions at all time during execution of the grouting work.

PART 3 EXECUTION

3.1 General

3.1.1 Damaged Holes

Any jet grout holes lost or damaged as the result of mechanical failure of equipment, inadequacy of grout, air, or water supplies, or improper drilling or injection procedures shall be backfilled with cement grout and replaced by additional jet grout holes that ensure a complete encapsulation of the damaged hole and re-establish a continuous cut-off at no additional cost to the Government.

3.1.2 Jet Grouting

Jet grout injection and jet monitor rotation and extraction rates shall be sufficient to produce grout columns/panels meeting the diameter, depth, overlap, and material property requirements specified herein. The required mixing tool rotational speeds and penetration/withdrawal rates for the various soil layers encountered shall be determined during the test section and be used during the balance of the work. If during a column section, these parameters are varied more than 15 percent from those determined during the test section, a replacement of the variant column section shall be installed, at no cost to the Government. Based upon conditions encountered during production, the Contractor may request that the established mixing parameters be modified during the production column installation, subject to approval of the Contracting Officer.

3.1.3 Design Mix

Proportion and inject jet grout mix so that the grout column produced meets the Acceptance Criteria Outline in paragraph "Acceptance Criteria".

3.1.4 Equipment

Equipment for mixing, holding, and pumping grout shall be in a secure location and shall be operated to minimize spillage of material. No material will be allowed to enter drainage areas.

3.2 TEST PROGRAM

The Contractor shall construct a test section of the jet-grouted elements in a location near the proposed jet grouting area and approved by the Contracting Officer to evaluate the Contractor's proposed methods and the grout mix's ability to produce grout columns meeting the depth, size, overlapping and material property requirements shown and specified herein, prior to starting jet grouting production work at the site. Execute test program in accordance with the procedures submitted herein and approved by the Contracting Officer.

3.2.1 Test Section Geometrics

A. Conduct a test program to evaluate the proposed grouting methods

SECTION 31 32 13.01 12 Page 13 ED 12-067 and the ability of the proposed grout mix to produce grout columns meeting the depth, diameter, overlap, and material property requirements shown on the Drawings and specified herein.

B. The Contractor shall select one representative location as a test section for the test program and this location shall be approved by the Engineer prior to starting the test program.

C. The test program shall be designed to verify the following items:

1. The range of column diameters and column strengths which can be achieved.

2. The column overlap and continuity between columns which can be achieved.

3. Maximum pressures that can be used before ground surface heave occurs.

D. The test section shall consist of 1 to 2 grout columns installed as specified for the production jet grouting work.

E. Execute the test program in accordance with the approved submittals. Mixing is to be controlled by shaft rotational speed, drilling speed, and grout injection rate. The Contractor shall expose columns from the test section for physical inspection. Measure the column diameter and compare with the design diameter.

F. After the jet grout columns have set up sufficiently, obtain a continuous core sample from one of the primary columns. Inspect the core and check for segregation. Select three samples from the core column and perform compression tests in accordance with ASTM D 1633 or ASTM D 2850 and permeabilty tests in accordance with ASTM D 5084, as appropriate.

G. Subject to the results of the test program, the Contracting Officer may require modifications in the jet grout column production to achieve satisfactory results.

3.2.2 Modifications

Subject to the results of the test program, the Contracting Officer may require modifications in the jet grout production to achieve satisfactory results. Depending on the extent of modifications necessary, the Contractor may be required to repeat the construction of a test section.

3.3 INSTALLATION OF JET GROUT COLUMNS/PANELS

The Contractor shall use the same equipment, materials, and procedures as those determined in the test program to give satisfactory results to perform production jet grouting for construction of the levee stability panels. The jet grout elements by installed by constructing a single line of overlapping grout columns/panels as shown with minimum diameters of 36 inches. Minimum overlap shall be at least 9 inches. Jet grouted columns shall be surveyed and checked by the Contractor before the start of drilling. At the completion of jet grouting operations, thoroughly clean site and dispose of waste slurry resulting from jet grouting operations. A minimum mixing time of five minutes and a maximum holding time of two hours will be enforced for the grout batching. The grout hold time shall be

SECTION 31 32 13.01 12 Page 14 ED 12-067 calculated from the beginning of the initial mixing.

3.3.1 Deviations

The installation of each column/panel shall be continuous. Deviations from plan locations at the ground surface shall not exceed 2 inches. Deviation from vertical at the ground surface shall not exceed 1 percent. Each column shall be designated uniquely.

3.3.2 As-Built Field Measurement Data

Within 30 days after completing all field activities, submit a final report detailing mix proportions, testing data, daily logs, and all quality control records as specified herein.

The results of at least one laboratory test shall be submitted demonstrating that the cement-bentonite installed provides a minimum unconfined compressive strength of 500 psi.

Jet Grouting Performance Records

Submit daily during the execution of the test and production jet grouting programs the following information:

1. Grout hole geometry (column/panel size, length and location).

2. Time and date of beginning and completion of each grout column.

3. Grout mix data, including mix proportions, batch quantities and spoil disposal quantities. Batch quantities shall be cross checked daily with theoretical cement dosages from pump data.

4. Erosion jet pressures used to construct each grout element.

5. Grout rates and takes for each grout column. The amount of fluid returns shall be recorded on daily reports for each 5-foot grout column interval.

6. Rates of rotation and withdrawal of jet grout monitor for each grout element.

7. Test samples taken from Soilcrete produced in test program and during production.

8. Other pertinent observations, such as: grout escapes, ground heave, or other unusual behavior. If loss of fluids, hydrofracture or inadvertant returns are observed in the borehole, via controls or anywhere on site, the Contractig Officer shall be notified immediately and corrective measures implemented under close observation.

3.4 ACCEPTANCE CRITERIA

The jet grout columns will individually be considered acceptable when the columns satisfy the criteria below. Columns not satisfying these criteria shall be replaced at no extra cost to the Government, by the Contractor, using appropriate methods. If a test fails, the Contractor may test the same column in another quadrant at the Contractor's expense.

SECTION 31 32 13.01 12 Page 15 ED 12-067

(a) Unconfined compressive strength of cores: 500 psi at 28 days. A maximum of 10 percent of the tested specimens can fall below 500 psi per tested column. If tests on adjacent cores fail at the same elevation, both cores are considered non-compliant.

(b) The columns have been installed to the predetermined design elevation shown on the drawings or to the satisfaction of the Contracting Officer's representative. The minimum top elevation of the column shall be the design elevation.

(c) The recorded length of the column has been verified as correct by the Contracting Officer's Representative.

(d) The geometric tolerances have been verified in accordance with paragraph QUALITY CONTROL. Horizontal alignment of the columns shall be within 2 inches of the planned location. The vertical inclination of columns shall be no greater than 1.0 percent. Horizontal overlap shall be at least 9 inches of a single column measured at the ground surface.

(e) The strength and uniformity have been confirmed to be in compliance with paragraph QUALITY CONTROL and the Unconfined compressive strength is 500 psi at 28 days.

(f) The injection of binder does not fall below 10 percent of the target rate as specified in paragraph MONITORING.

(g) The recovery percentage of cores taken for strength verification purposes was greater than 80 percent.

(h) No 5-foot segment of column may contain more than 20 percent of its volume comprised of unimproved soil, and any individual or aggregation of lumps of unimproved soil must be no larger than 12 inches in greatest dimension. For making this determination, a single core is deemed representative of the entire cross section of a column. Any material not recovered during coring will be considered unimproved soil.

(i) Perform permeability testing of core samples at 28 days in accordance with ASTM D 4138. The permability for a fixed sample shall be less than 1x10-6 cm/s.

(j) Set Time and Bleed: Grouts shall have a set time determined during mix design and the test section, and be indicated on the shop drawing.

Samples shall be obtained at least once every shift for set time checks and bleed (1 and 2 hour). All samples shall be properly labeled and stored until the completion of the project.

3.4.1 Remedial Measures

Columns not satisfying the Acceptance Criteria shall be replaced at no extra cost by the Contractor, using methods approved by the Contracting Officer's Representative. If a test fails, the Contractor may test the same column in another quadrant at the Contractor's expense. If a column in a panel does not meet strength, uniformity and permability requirements, a replacement panel shall be installed at Contractor's expense to encapsulate the column that did not pass the acceptance requirements. Alternatively, the Contractor may elect to core and test the two adjacent columns at the depth in the panel where the test failed. If both tests pass, the column will be deemed acceptable. Remedial measures shall be included in the

SECTION 31 32 13.01 12 Page 16 ED 12-067

Quality Control Plan.

3.5 COLLECTION AND DISPOSAL OF WASTE SLURRY RESULTING FROM JET GROUTING

OPERATIONS

3.5.1 Stockpiles

No material shall be stockpiled within 50 feet of existing canal banks or existing structures without approval of the Contracting Officer.

3.5.2 Disposal of Debris and Containment for Grout Spoils

At all times during and at completion of waste slurry resulting from jet grouting operations, the site shall be maintained clear of all debris. Use extreme care to prevent discharge of grout into the adjacent jurisdictional waters. All grout, water, and other drilling/grouting waste material shall be contained within the work areas with berms or other measures. Stormwater control best management practices shall be employed at all times in accordance with site permits. Clean up any grout discharges, spoils, or other unacceptable environmental impacts immediately. Provide continuous vacuum truck removal around jet areas to contain any potential discharges, as needed. The Contractor shall regularly dispose of all waste materials in accordance with Section 01 57 20.00 12 ENVIRONMENTAL PROTECTION.

3.6 PREVENTION OF GROUND HEAVE

In order to prevent ground heave and the potential for discharging grout into jurisdictional waters or potential for damaging the existing levee structures during jet grouting, appropriate drilling procedures shall be used consistent with best industry practices. The Contractor shall submit a procedure for maintaining a clear bore hole and preventing ground heave and inadvertent discharges for information only. The approved procedure shall be used in the test program and utilized during construction of the production columns.

To mitigate the effects of potential loss of fluids or hydro fracture, appropriate procedures shall be used to maintain a clear borehole for return of spoils at all times during grouting operations. Grouting operations shall be interrupted in case the return of the spoil is blocked.

Grouting shall resume when proper return of flow is restored.

The amount of fluid returns shall be recorded on daily reports for each 5-foot grout column interval. If loss of fluids, hydro fracture or inadvertent returns are observed in the borehole, controls or anywhere on site, the engineer shall be notified immediately and conditions closely monitored to implement necessary corrective measures. Protection of existing levees shall be the highest priority.

-- End of Section --

SECTION 31 32 13.01 12 Page 17 ED 12-067

H447694_S-106---.dgn 11/13/2012 3:04:19 PM

1.13 JOB CONDITIONS

3.6 PREVENTION OF GROUND HEAVE

H447694_S-106---