W912EP18R0019_Amendment_0003.pdf

W32CS580716242

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 SF30 Continuation Page for Details.

The proposal due date remains 11 September 2018 at 2:00PM local time.

1. CONTRACT ID CODE PAGE OF PAGES

J 1

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 W912EP18R0019

X 9B. DATED (SEE ITEM 11)

03-Aug-2018

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, 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.

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

6. ISSUED BY

3. EFFECTIVE DATE

07-Sep-2018

CODE

USA ENGINEER DISTRICT, JACKSONVILLE

CONTRACTING DIVISION

701 SAN MARCO BLVD

JACKSONVILLE FL 32207-8175

W912EP 7. ADMINISTERED BY (If other than item 6)

4. REQUISITION/PURCHASE REQ. NO.

CODE

See Item 6

FACILITY CODECODE

EMAIL:TEL:

X

SF 30 CONTINUATION SHEET

Herbert Hoover Dike Rehabilitation Dam Modification Cutoff Wall MATOC Palm Beach and Hendry Counties, Florida

W912EP-18-R-0019 1 Amendment 0003

SUMMARY OF CHANGES

1. SPECIFICATIONS:

The text changes have been updated with additions noted by underlined text and deletions noted by line/cross-outs, and pertain only to changes made by this amendment. The entire section is replaced if there is any change. The Project Table of Contents and Submittal Register are replaced without underlines and cross-outs if there are changes to these documents. New sections are added without underlines and cross-outs.

Changes to Specifications:

Volume 1 of 2 – Contract Clauses (Base MATOC):

REMOVE the requirement for a bid bond to be submitted with a proposal for the base MATOC.

Volume 2 of 2 – Technical Specifications (Base MATOC):

DELETE Section 02 32 00 and REPLACE with the attached revised Section 02 32 00.

DELETE Section 35 41 17 and REPLACE with the attached revised Section 35 41 17.

DELETE Submittal Register and REPLACE with the attached revised Submittal Register.

2. DRAWINGS:

Base MATOC:

No Change

(End of Summary of Changes)

Herbert Hoover Dike Rehabilitation Project Dam Modification Cutoff Wall MATOC

SECTION TABLE OF CONTENTS

DIVISION 02 - EXISTING CONDITIONS

SECTION 02 32 00

VERIFICATION DRILLING AND PERMEABILITY TESTING OF IN-PLACE CUTOFF WALL

PART 1 GENERAL

1.1 REFERENCES

1.2 SYSTEM DESCRIPTION

1.2.1 Core Drilling

1.2.2 In-situ Permeability Testing

1.2.3 Wall Segment

1.3 SUBMITTALS

1.4 SEQUENCING AND SCHEDULING

1.5 QUALIFICATIONS

1.5.1 Cutoff Wall Driller

1.5.2 Borehole Logger

1.5.3 Hydrogeologist

1.5.4 Borehole Camera Specialist

PART 2 PRODUCTS

2.1 CORE BOXES

2.2 LABELS

2.3 BOREHOLE CAMERAS

2.3.1 Optical Televiewer (OPTV) Borehole Camera

2.3.2 Closed Circuit Television (CCTV) Borehole Camera

2.4 Electronic Water Level Gauge (Pressure Troll)

PART 3 EXECUTION

3.1 CORE DRILLING

3.1.1 Equipment and Supplies

3.1.2 Procedure

3.1.3 Casing Installation

3.1.4 Drilling Deviation Measurements

3.1.5 Photographs of Retrieved Samples

3.1.6 Arrangement of Core

3.1.7 Preservation of Core

3.1.8 Labeling, Marking and Packing Core

3.1.9 Selection of Test Samples

3.1.9.1 Unconfined Compressive Strength Testing

3.1.10 Disposition of Core

3.2 BOREHOLE CAMERA SURVEYS

3.2.1 Optical Televiewer (OPTV) Logging

3.2.2 Closed Circuit Television (CCTV) Video Recording

3.3 IN-SITU PERMEABILITY TESTING

3.3.1 Equipment and Supplies

3.3.2 24-Hour Falling Head Permeability Test

3.4 DISPOSITION OF BOREHOLES WITH APPROVED TESTS

3.5 ABANDONED AND SUPPLEMENTAL VERIFICATION BORINGS

SECTION 02 32 00 Page 1 W912EP-18-R-0019 Amendment 0003

3.6 DECOMMISSIONING

3.7 RECORDS

-- End of Section Table of Contents --

SECTION 02 32 00 Page 2

SECTION 02 32 00

VERIFICATION DRILLING AND PERMEABILITY TESTING

OF IN-PLACE CUTOFF WALL

PART 1 GENERAL

1.1 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.

ASTM INTERNATIONAL (ASTM)

ASTM C511 (2013) Standard for Mixing Rooms, Moist Cabinets, Moist Rooms, and Water Storage.

Tanks Used in the Testing of Hydraulic Cements and Concretes.

ASTM D2113 (2014) Rock Core Drilling and Sampling of Rock for Site Investigation

ASTM D2166/D2166M (2016) Standard Test Method for Unconfined Compressive Strength of Cohesive Soil

1.2 SYSTEM DESCRIPTION

This section specifies requirements for verification drilling and testing (Verification Borings) of hardened conventional cutoff wall backfill specified in Section 02 35 29 CONVENTIONAL CUTOFF WALL and jet grout soil-cement specified in Section 35 41 17 JET GROUT CUTOFF WALL. Provide verification borings at locations directed by the Contracting Officer to evaluate conformance with Performance Criteria. Perform all Verification Borings Monday through FridaySaturday (8AM through 5PM). The equipment and techniques to be used shall be submitted in the Cutoff Wall Drilling Plan.

1.2.1 Core Drilling

Drilling of cores shall be by any approved standard and accepted method of rotary core drilling (ASTM D2113) that will provide continuous and complete cores of the required diameter over the entire depth of the constructed cutoff wall.

1.2.2 In-situ Permeability Testing

In-situ permeability testing is the process of introducing water into or extracting water out of the cutoff wall through verification borings for the purpose of determining the in-situ permeability of the cutoff wall.

1.2.3 Wall Segment

A Wall Segment is defined as any Demonstration Section, minimum distance of conventional cutoff wall placed before a verification boring is required, or jet grout cutoff wall that connects to the side of an existing

SECTION 02 32 00 Page 3 structure. See paragraph SEQUENCING AND SCHEDULING below.

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. The following shall be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

Cutoff Wall Drilling Plan; G, DO

Prior to starting work, the Contractor shall submit a plan for drilling, sampling, testing, and safety. The plan shall include, but not be limited to; the proposed method of drilling and sampling including a description of the sampling and testing tools that will be used, a listing of any subcontractors to include a description of how the subcontractors are to be used and a description of all methods and procedures to be utilized to ensure a safe operation and to protect the environment. No work shall be performed until this plan has been approved and no deviation from the approved plan will be permitted without prior approval by the Contracting Officer.

Verification Boring Reports; G, DO

The Contractor shall submit for each complete verification boring, legible copies of verification boring reports in accordance with paragraph RECORDS below.

In-Situ Permeability Testing Plan; G, DO

The Contractor shall submit a plan for in-situ permeability testing. The plan shall include, but not be limited to; a description of all methods and procedures for performing the in-situ permeability testing, data reduction, manufacturer's data specification sheets for all equipment and materials to be used, and calibration certificates dated within 60 days prior to the start of testing, or within the manufacturer's recommended calibration interval for on all pressure gauges and flow meters used during the in-situ testing.

Include/describe in this plan the following:

a) Proposed methods and procedures for performing in-situ permeability testing. Include the proposed form used to document time and water level readings and other data pertinent to permeability testing.

b) Procedures for collecting and analyzing all flow rate-time-water level data from the falling head test.

c) The in-hole submersible pump size, geometry, characteristic curves, and manufacturer's operating manuals. The selected pumping equipment shall eliminate any electromagnetic influence that could affect the resolution of the borehole camera.

SECTION 02 32 00 Page 4

d) Sketches detailing how all equipment (pump, camera, power supply wire, and plumbing) will be simultaneously inserted into the borehole for observing the quality of the in-situ cutoff wall under external water pressure during testing.

e) Details of how the water level will be kept low enough after testing to accommodate a full borehole CCTV camera survey in a dry hole.

BOREHOLE CAMERAS; G, DO

Provide manufacturer's data specification sheets and operating manuals for the borehole camera(s) to be used for the borehole surveys described in PRODUCTS below. Indicate in the submittal the capabilities of the encoder to provide date and time stamps on the video. Include sample pictures and video from borehole cameras to demonstrate the required quality is achieved.

Electronic Water Level Gauge (Pressure Troll); G, DO

Provide manufacturer's data specification sheets and operating manuals for the electronic water level gauge (pressure troll) as described in PRODUCTS below.

Casing Installation Plan; G, DO

Submit a plan detailing the installation process for the required continuous steel or PVC casing that connects the top of the work platform to the top of the cutoff wall for QC testing. This plan shall indicate the methodology for casing installation, size and length of casing, and the means of providing a watertight seal between the casing and top of the cutoff wall as described in paragraph CASING INSTALLATION below. The casing size provided shall be large enough to accommodate all testing and inspection equipment. If steel casing is used, the Contractor shall ensure that the appropriate camera type and/or precautions are taken to eliminate interference with down hole cameras.

SD-06 Test Reports

Core Disposal Notification

Notify the Contracting Officer 30 calendar days prior to disposal of cores as required in subparagraph "Disposition of Core" in paragraph CORE DRILLING below.

SD-07 Certificates

Experience and Qualifications; G, RO

The Contractor shall submit evidence of qualification experience of the Cutoff Wall Driller, the Borehole Logger, the Hydrogeologist, and the Borehole Camera Specialist. See paragraph QUALIFICATIONS below.

1.4 SEQUENCING AND SCHEDULING

Acceptance of a Wall Segment will not be given until the verification

SECTION 02 32 00 Page 5 drilling and testing is performed and the performance requirements are satisfied. The Contractor shall plan activities accordingly considering the following:

a. The location of verification borings shall be determined by the Contracting Officer; the Contracting Officer may vary locations as field conditions warrant. Verification borings may be performed at panel/element overlaps, connections of new to existing cutoff wall, connections of conventional to jet grout cutoff wall, or any other location within the cutoff wall. Verification boring locations will be determined within ten (10) business days after placement of a cutoff wall segment.

b. For planning purposes, assume verification borings with the following minimum frequency:

(1) One (1) verification boring for every 250 linear feet (LF) of conventional cutoff wall constructed.

(2) One (1) verification boring, but no less than two per side of an existing structure, for every fifty (50) LF of jet grout cutoff wall constructed.

(3) One (1) verification boring at each conventional cutoff wall and jet grout cutoff wall connection.

(4) If applicable to the Task Order, one (1) verification boring at each connection to existing cutoff.

(5) If applicable to the Task Order, five (5) verification borings shall be performed in a Demonstration Section.

(6) Three (3) to five (5) verification borings shall be performed in the Pre-production Trial Program. See Section 35 41 17 JET GROUT CUTOFF WALL, paragraph PRE-PRODUCTION TRIAL PROGRAM VERIFICATION

TESTING.

c. The Contracting Officer may reduce the frequency of verification borings as field conditions warrant. Verification borings may be added or deleted as required by the Contracting Officer. Additional verification borings that exceed the specified quantity above will be paid at the unit rate.

d. On a Task Order basis, allow in the estimate for up to five (5) of the verification borings described above to be inclined at an angle of 30 degrees or less from vertical.One (1) inclined verification boring will be performed at each jet grout Wall Segment. Inclined borings, if used, will be used to verify jet grout cutoff wall locations and the jet grout connection to conventional cutoff wall. The Contractor will not be entitled to any compensation for delays, standby time, reduced efficiencies, or other similar costs due to the time required for performing inclined verification borings.

1.5 QUALIFICATIONS

1.5.1 Cutoff Wall Driller

The cutoff wall driller shall have experience operating drilling equipment similar to the equipment to be used for this contract and coring through

SECTION 02 32 00 Page 6 conventional cutoff wall backfill and jet grout soil-cement walls with properties similar to that specified in Section 02 35 29 CONVENTIONAL CUTOFF WALL and 35 41 17 Jet Grout CUTOFF WALL. The driller must be able to consistently achieve the target minimum Core Recover and RQD unless there is evidence the material is defective. The experience shall include a minimum of 3 years of performing geotechnical drilling and the previous completion of at least 3 projects requiring coring to depths of at least 60 feet using equipment similar to that being used for this contract.

1.5.2 Borehole Logger

The Borehole Logger shall be a Geologist or Geotechnical Engineer, licensed in any state, experienced in subsurface exploration to oversee all drilling, sampling, and in-situ testing operations. This individual shall also be responsible for the preparation of all samples for delivery.

The presence of a Government representative or the keeping of separate drilling records by the Contracting Officer shall not relieve the Contractor of the responsibility for the work specified in this specification.

1.5.3 Hydrogeologist

The Hydrogeologist shall be an individual who has had experience with at least five (5) projects of cutoff wall or bottom seal construction requiring in-situ permeability testing using the methods proposed for this contract. A qualified geologist or geotechnical engineer that meets the requirements above can also serve as the Hydrogeologist.

1.5.4 Borehole Camera Specialist

Provide a qualified Borehole Camera Specialist with applicable demonstrated experience on at least 3 projects (performed within 5 years of NTP) in the operation and maintenance of borehole cameras and field operated video recording equipment.

PART 2 PRODUCTS

2.1 CORE BOXES

Longitudinally partitioned, hinged top, core boxes shall be used for all cores.

2.2 LABELS

Core boxes shall be clearly identified by permanent marker or stenciled labels. The information on this label shall contain the following:

PROJECT: HERBERT HOOVER DIKE REHABILITATION,

DAM MODIFICATION CUTOFF WALL

MATOC TASK ORDER (place task order number here)

HOLE NO.: STATION __________

CORE DEPTH: __________ to __________

BOX NO.: __________

SECTION 02 32 00 Page 7

TOTAL NUMBER OF BOXES FOR THE HOLE: __________

2.3 BOREHOLE CAMERAS

Two types of borehole cameras are required:

2.3.1 Optical Televiewer (OPTV) Borehole Camera

The OPTV borehole camera is for making a 360 degree log of the verification boring. The camera shall meet the following minimum requirements:

TYPE: Digital Optical Borehole Televiewer.

FRAME RATE: 20 Hz.

EXPOSURE: 6.

LIGHTING: 10.

RESOLUTION: 900 pixels.

LOGGING SPEED: 2.9 feet/minute.

2.3.2 Closed Circuit Television (CCTV) Borehole Camera

The CCTV borehole camera is for video logging the verification boring with the water pumped out of the borehole. The camera shall meet the following minimum requirements.

a. The camera and all attached appliances shall fit within any borehole and/or rotary exploratory hole used on the project. The camera shall be able to easily pass through the entire length of all holes. It should be noted that a submersible pump, power supply cable and discharge piping will be positioned in the borehole during the camera run and the camera must also be able to traverse the borehole with this in-place equipment.

b. The camera must be capable of operating to a maximum depth of 50 feet of water (22 psi).

c. The camera shall be able to view directly down the borehole, and also have pan/tilt and 360 degrees rotation of the camera field of view. Alternatively, the CCTV camera can have direct viewing down hole and laterally to view the sidewalls of the corehole. All other requirements for CCTV camera shall be adhered to.

d. Video camera and monitor shall be color and high resolution.

e. A DVD recorder, or digital media recorder (as approved by the Contracting Officer) shall be provided with the borehole camera and be used to instantaneously record images captured by the borehole camera.

f. Camera must be capable of operating inside any hole for a minimum of 4 hours without fogging or condensation and should be able to operate in wet or dry conditions. The camera shall be able to operate at a temperature of at least 122 degrees Fahrenheit.

g. The camera shall have a minimum variable lighting of 20 lux @ 1 meter and prevent any glinting (reflective light) problems with viewing the side walls of any bore hole.

h. Camera shall be self-focusing or remotely controlled manually.

All camera functions including focus, iris, camera orientation and

SECTION 02 32 00 Page 8 lighting intensity shall be controllable from the surface, either manually or automatically.

i. A controller and encoder shall be provided and will project onto the color monitor and stamp digital image with the following information in real time: hole or location identification, clock time (resolution to 1/30 second or better) and location (depth measured from the work platform surface) and orientation.

j. The color image shall be compliant with National Television System Committee format (i.e., a closed circuit television (CCTV) camera format) and have a scan rate of at least 620 lines at 50 HZ, and a resolution of at least 320 lines TV.

k. Camera shall be lowered and raised manually or by using an electrically powered winching system, with depth encoder and LCD depth display integrated into the winching system.

l. When anomalies, voids, inclusions, or cracks are observed isolate the zone by obtaining the depth and elevation and compass orientation (N-S-E-W) of the field of view using the OPTV camera to determine the azimuth and depth of the zone. These images will be used to supplement the CCTV camera video.

2.4 Electronic Water Level Gauge (Pressure Troll)

An electronic water level gauge, or pressure troll, is an in-hole electronic water level instrument with pocket PC data logging capabilities.

The pressure troll shall be used to monitor the water level changes and water temperature during the falling head testing. The pressure troll selected shall have the following minimum technical specifications:

a. Primary sensor shall be a piezoresistive titanium pressure sensor, with a gauged (vented) pressure range of 30 psig (69 feet of water).

Pressure accuracy shall be +/-0.05% FS @15 Deg Celsius, and +/-0.1% across the entire pressure / temperature range of the device. Sensor shall have a resolution of +/-0.005% FS or better.

b. Temperature sensor shall be a silicon based sensor with a temperature range of -20 Deg C to 80 Deg. C. Temperature accuracy shall be +/- 0.1 Deg C, with a resolution of +/-0.01 Deg C.

c. Pressure troll shall have automatic temperature compensation, along with automatic barometric compensation using vented cables.

Vented cables shall have a replaceable desiccant bottle which screws directly to the vented cable.

d. Cables for up to 80 feet of testing shall be vented, quick connect type cables shall be jacked in blue polyurethane coating, with twist-lock titanium connectors. Cables shall be spooled on a steel reel.

e. Probe shall a maximum outer diameter of 0.75 inches and be made of titanium.

f. The probe shall have a built-in non-volatile memory (4 MB) and be able to store internally up to 200,000 data records, (one date record = date, time, water head, temperature).

g. The device shall be able to perform fast logging with rates of 4

SECTION 02 32 00 Page 9 scans per second, both pressure head and temperature.

h. Data acquisition shall be via a ruggedized pocket PC (running Microsoft Mobile operating system), with software logging capabilities from fast linear scanning to logarithmic decay scheduling. Data export shall be via a USB cable or network hub. Data shall be able to be exported to Microsoft Excel, in a specified data format for import into the numerical analysis package used to calculate the permeability.

i. Calibration certificates traceable to NIST shall be part of the submittal for the pressure troll equipment

j. Data submission protocols and transfer with chain-of-custody and point-of-source control of data shall be established jointly between the Contractors QC personnel and USACE QA Personnel.

PART 3 EXECUTION

3.1 CORE DRILLING

Core drilling for verification borings or other quality control tests shall be done sufficiently in advance, so as to permit testing at the prescribed age and may commence on or before 28 days and will be permitted five (5) days beyond 28 days during holidays or adverse weather conditions, however the core quality required in paragraph "Procedure" below and "Acceptance Criteria" specified in Section 02 35 29 CONVENTIONAL CUTOFF WALL and Section 35 41 17 JET GROUT CUTOFF WALL must be achieved. Provide 72-hour notification prior to any drilling activities. The notification shall include the location of the boring, the exact time the boring is scheduled to start, and the anticipated completion time. Once notification has been given to the Contracting Officer, the schedule shall not be changed without approval of the Contracting Officer.

3.1.1 Equipment and Supplies

Equipment to be furnished by the Contractor for core drilling shall include core-drilling machinery of a type or types approved by the Contracting Officer complete with all the accessories needed to take continuous cores.

The coring technique selected by the Contractor shall be capable of obtaining samples to a depth of at least 80 feet. Cored samples of constructed cutoff wall shall be sufficient in size and allow insertion of all the in-hole tools for in-situ permeability testing to fit inside the entire length of the hole. Cored samples shall consist of hardened cutoff wall material obtained in a maximum of 5-foot long runs. Supplies for core drilling to be furnished by the Contractor shall include, but not be limited to, all casing, drill rods, core barrels, coring bits, piping, drilling fluids (except bentonite), pumps, potable water, tools, and power required for drilling, all boxes and containers required for core samples, and wet saw for cutting samples . Bentonite shall not be used as a drilling fluid; only synthetic drilling muds, water flush, or foam flush are acceptable for coring. Selection of the type of bit shall be at the Contractor's discretion provided that the selected bit produces high quality cores capable of providing suitable samples for testing, produces smooth borehole walls to produce high quality video logs, and does not damage the cutoff wall. Care shall be taken not to damage core samples while handling and transportation. Drilling equipment shall be capable of drilling inclined as well as vertical core holes as specified.

SECTION 02 32 00 Page 10

3.1.2 Procedure

The Government reserves the right to make adjustments to any of the Procedures based on conditions observed during this MATOC. All boreholes shall be drilled vertically, with the exception of inclined borings at jet grout cutoff Wall Segments which shall be drilled at the angle directed by the Contracting Officer, to within 2 foot of the finished depth of the cutoff wall taking care to not penetrate the bottom of the cutoff wall.

The Contractor shall operate his drills at such speeds and with such down pressures and shall control drill fluid pressures and quantities to ensure maximum core quality and recovery and minimize any damage to the cutoff wall. As measured per core run, the drilling methods shall provide Core Recovery (CR) of at least 85 percent for Jet Grout Cutoff Wall and 90 percent for Conventional Cutoff Wall and Rock Quality Designation (RQD) of at least 85 percent. Additional core drill locations may be required at no additional cost to the Government if CR or RQD are below the required values and adequate samples for laboratory testing are not recovered.

If during any core run excessive mechanical breaks/fractures (defined as 3 or more per feet of core run) are observed or low Core Recovery (defined as CR < 85 percent) is achieved, investigate and correct the issue before proceeding to the next core run. Make modifications to the drilling procedures, drilling equipment, or drilling methods as necessary and amend the Cutoff Wall Drilling Plan to reflect the modifications.

Care shall be taken to ensure that the borehole is positioned through the centerline of the cutoff wall, unless otherwise directed. Verification Borings for jet grout cutoff wall or panel type methods will typically be located at element overlaps. The Borehole Logger shall exercise particular care in recording zones of water loss, apparent voids or cavities, rod jerks, rough drilling and other unusual and non-ordinary coring experiences. The alignment of all verification boring shall be measured continuously and provided graphically and shown on the as-builts. Upon completion of core drilling, the hole shall be cleaned with potable water containing bleach at 1 gallon of 5.25% sodium hypochlorite per 100 gallons of water and flushed until effluent water is clear. The borehole shall then be flushed with potable water to remove any bleach. If water is used as the drilling fluid then bleach does not need to be used when flushing the borehole. The borehole wall shall be free and clear of any residual drilling fluids. Water under low pressure shall be applied so as not to damage borehole wall.

3.1.3 Casing Installation

If required, a steel or PVC casing shall be installed between the top of the working platform and the top of the cutoff wall to be tested. The casing size provided shall be large enough to accommodate all testing and inspection equipment. The casing shall provide a watertight seal with the cutoff wall and shall have a removable end cap. Installation shall be in accordance with the approved Casing Installation Plan. The casing and end cap shall be accessible for additional testing requirements for up to 30 days following installation, or as approved by the Contracting Officer.

3.1.4 Drilling Deviation Measurements

Drilling deviation measurements shall be performed for every quality control coring or rotary exploratory hole, using an instrument capable of biaxial deviation measurement to determine the magnitude and azimuth of all down-the-hole deviations. The equipment used to satisfy the requirements

SECTION 02 32 00 Page 11 from measuring drilling deviation in Section 35 41 17 Jet Grout Cutoff Wall may be used. The drilling deviation measurements shall be obtained over the entire length of the drill hole. The instrumentation used in drilling deviation measurement shall have the capability of measuring down a depth of at least 80 feet. All quality control and quality assurance holes shall be superimposed on the plan and profile views of the conventional and jet grout cutoff wall As-builts using the drilling deviation measurements.

3.1.5 Photographs of Retrieved Samples

Color digital photographs shall be taken of each retrieved core run to record its initial condition prior to laboratory sample selection or preservation in boxes. Each photograph shall contain a full length rule for scale and clearly legible sample identification. Samples shall be fresh, wet, and cleaned of all mud, un-mixed or un-cemented soil, drill cuttings, or debris. Photographs shall be well composed, focused on the sample, and with the sample filling the entire picture. Photograph lighting shall be consistent and well lighted and avoid shadows. Additional lighting shall be provided if photographs are taken at dusk, dawn, or when cloud cover that affects the lighting, as determined by the Contracting Officer, is present. A light tent is recommended.

3.1.6 Arrangement of Core

All cores shall be washed and arranged neatly in the partitioned boxes in the same sequence in which they occurred before removal from the hole.

Facing the open box with the hinged cover above and the open box below, cores shall be arranged in descending sequence beginning at the left end of the trough nearest the hinges and continuing in the other troughs from left to right. The highest part of the core shall be placed in box 1, and the lower portions of the core shall be placed in the other boxes in consecutive order.

3.1.7 Preservation of Core

The core shall be washed, wrapped in clear visqueen or cheese cloth and then sealed by applying paraffin wax, microcrystalline wax, or 50/50 mixture of paraffin and microcrystalline wax prior to placing the core in the core box. This sealing process shall be accomplished as soon as possible after the core is removed from the core barrel to prevent desiccation of the core. Other methods of preservation may be applied (as written and approved in the Cutoff Wall Drilling Plan) so long as it yields the same degree of core preservation. All core samples selected for testing shall be stored in a laboratory moisture room having constant temperature, saturated environment meeting the requirements of ASTM C511 until tested or until otherwise directed by the Contracting Officer. The remaining core not to be tested in the filled core boxes shall be protected from direct sunlight, precipitation, and freezing by some form of shelter that allows ventilation to the boxes. The minimum length of each preserved core shall have length to diameter (L/D) ratio no less than 2.5. All cored material with L/D greater than or equal to 2.5 shall be fully preserved. All cored materials with L/D less than 2.5 shall be placed in the core boxes without preservation.

3.1.8 Labeling, Marking and Packing Core

Labels for core boxes complying with paragraph CORE BOXES shall be placed on the inside and outside of the top cover in addition to each end. In addition, the depths (or elevations) of each core run/pull shall be marked

SECTION 02 32 00 Page 12 with a black waterproof pen on the spacer blocks that are placed between core pulls. If the label is altered, corrected, or otherwise changed, completely cover the out-of-date label by spray painting the entire affected area to a solid white background prior to re-labeling. When information is changed after the hole is complete due to errors during drilling, provide clear explanation of what the error was in writing. When a box is full, the space between the core and the trough sides shall be filled with suitable packing material. Spacer blocks shall consist of 2-inch to 2.5-inch nominal outer diameter Schedule 40 PVC pipe. Spacer blocks shall be cut to the same length of the sample and be marked with appropriate labels (QA/QC sample I.D, top/bottom EL., etc.) and placed in the core box to show where samples have been removed.

3.1.9 Selection of Test Samples

Representative samples of core shall be selected for testing by the Contracting Officer at the completion of each Verification Boring. Two (2) core samples, one (1) QC and one (1) QA, shall be collected at each zone of the top, middle, and bottom one-third depths of each verification boring, for a total of six (6) samples per boring.

3.1.9.1 Unconfined Compressive Strength Testing

From each borehole at each depth range, conduct one (1) unconfined compressive strength (UCS) test on cored samples, for a total of three (3) tests per corehole. The tests shall be performed in accordance with ASTM D2166/D2166M. The tests shall be performed within 10 days of samples collected. Additional tests required due to failed tests shall be at Contractor's expense. Minimum UCS shall be as specified in Section 02 35 29 CONVENTIONAL CUTOFF WALL and Section 35 41 17 JET GROUT CUTOFF WALL.

3.1.10 Disposition of Core

For purposes of planning for storage of cores, the Task Order shall be equally divided into three (3) phases by the Contractor. Upon acceptance of all Wall Segments in a given phase, the cores shall be disposed of by the Contractor; however, the Contractor shall provide a Core Disposal Notification to the Contracting Officer 30 calendar days prior to disposal of the cores to allow the Government to take possession of any core samples.

3.2 BOREHOLE CAMERA SURVEYS

Following completion of coring, perform an OPTV and CCTV survey to document the quality of the cutoff wall material in the hole sidewalls. The borehole camera surveys shall be uploaded to the Contractor provided FTP site within 24 hours of performing the surveys.

3.2.1 Optical Televiewer (OPTV) Logging

Make a 360-degree log of the entire borehole of all quality control corings/borings and quality assurance verification borings performed in the cutoff wall, projected as a "flat core", and showing orientation, depth, and elevation in NAVD88. Depth shall be measured from work platform surface. OPTV logging shall be performed with the borehole full of water after completion of borehole cleaning and flushing. Format of final video logs shall be of high resolution quality.

SECTION 02 32 00 Page 13

3.2.2 Closed Circuit Television (CCTV) Video Recording

Make a CCTV video recording of all verification borings performed in the cutoff wall. The intent is to observe the hole with the water drawn down as much as possible. Depth shall be measured from the work platform surface. CCTV recording shall be performed after borehole cleaning and flushing and with the borehole pumped out so that the borehole is under external water pressure. Insert the camera into the borehole and slowly lower to inspect the entire borehole. Upon extraction, the camera shall be rotated to present the entire borehole circumference for inspection. If the camera lens becomes foggy, gets wet, or is otherwise affected and degrading the quality of the field of vision, correct the issue and re-run recording.

When practicable, the water pump shall be removed leaving only the CCTV to allow better field of vision. Zones with anomalies, varying quality, or cracks shall be tracked and annotated on the Drilling Logs along with a description of what was observed, the corresponding elevations, and the appropriate (N-S-E-W) field of view obtained using the OPTV camera.

3.3 IN-SITU PERMEABILITY TESTING

After completion of the borehole camera surveys, test each verification boring as described below and in accordance with the In-Situ Permeability Testing Plan to determine the effective permeability of the cutoff wall.

Provide the Contracting Officer with 72-hours written notification of any in-situ permeability test. The notification shall include the location and exact time of the test. The Hydrogeologist shall be present during permeability testing performed in the Demonstration Section to establish the approved methods and procedures that will be used during Production Work; only the Borehole Logger is required for subsequent testing. The final test results shall be signed and sealed by a Registered Engineer.

Water level versus clock time shall be recorded using the pressure troll equipment, with automated data logging and manual methods as a back-up.

Manual readings shall be taken and recorded at the beginning and at the end of each test. The Contractor is allowed to pre-soak the borehole. The Contractor may be required to make check tests at his own expense if the testing equipment or its assembly and arrangement are found to be faulty after the testing of any holes. Record all time and water level readings made on a suitable form approved by the Contracting Officer as included in the In-Situ Permeability Testing Plan. The Contracting Officer may vary test procedures as field conditions warrant.

3.3.1 Equipment and Supplies

In-situ permeability testing equipment and supplies to be furnished by the Contractor shall be submitted in the In-Situ Permeability Testing Plan. The Contractor shall choose equipment and procedures that will minimize potential damage to the wall. The instrumentation used shall have the capability of extending to a depth of at least 80 feet. All equipment and supplies used for In-Situ permeability testing shall be approved by the Contracting Officer prior to use.

The Contractor shall also have a weighted tape with buzzer for obtaining manual water level readings.

3.3.2 24-Hour Falling Head Permeability Test

a. After completion of the CCTV inspection, install the pressure troll in the hole and fill the hole with potable water to top of casing or cutoff wall, as appropriate, maintaining the water level for a 24-hour

SECTION 02 32 00 Page 14 stabilization period.

b. After the 24-hour stabilization period, initiate the falling head test by filling the hole with potable water to the top of casing or cutoff wall, as appropriate, and begin taking and recording readings in accordance with the approved plan.

c. Take readings at 30 second intervals until the water column falls within ten (10%) percent of the static borehole water level, defined as lake level at the time of testing, or twenty-four (24) hours has passed; whichever comes first.

d. Calculate permeability for each time interval using the following formula:

K=A*ln(H1/H2)/(F*(t2-t1))

Where;

K = hydraulic conductivity (permeability), cm/sec A = cross sectional area of the verification hole H2 = head at time t2 H1 = head at time t1 F = shape factor determined from Figure 1 below t = elapsed time

On Figure 1 below;

L = length of test hole i.e. depth of verification boring B = element thickness measured perpendicular to the cutoff wall axis at the verification hole location D = diameter of test hole.

SECTION 02 32 00 Page 15

3.4 DISPOSITION OF BOREHOLES WITH APPROVED TESTS

After all QC and QA evaluations have been performed and the results have been approved by the Contracting Officer, the Contractor shall backfill the borehole as required in paragraph DECOMMISSIONING below.

3.5 ABANDONED AND SUPPLEMENTAL VERIFICATION BORINGS

Abandoned verification borings shall be those that drift outside the wall during drilling or those that cannot be drilled to the required depth. The Contractor shall request approval from the Contracting Officer prior to abandonment. All records and test results obtained shall be submitted to the Government. Each verification boring that is abandoned by the Contractor shall be supplemented by another verification boring adjacent to the original. A verification boring shall not be abandoned as a result of a failing acceptance test. Actual locations of any supplemental verification borings will be established by the Contracting Officer. No payment will be made for borings that were abandoned. Approved abandoned verification boring holes shall be backfilled as required in paragraph DECOMMISSIONING below.

3.6 DECOMMISSIONING

The Contractor shall preserve each hole in good condition until directed by the Contracting Officer to fill the hole. All verification borings and water level monitoring wells shall be decommissioned as described in Section 33 29 00 DECOMMISSIONING WELLS. No separate payment will be made for decommissioning verification borings and monitoring wells. The cost of this work shall be included in the drilling costs.

3.7 RECORDS

The Contractor shall keep accurate driller's logs, water levels, photographs, Verification Boring Reports, decommissioning logs, and records of all work accomplished under this contract and shall deliver complete, legible color copies of these logs and records to the Contracting Officer with applicable in-situ and laboratory testing identified before acceptance of a Wall Segment. All such records shall be recorded during the actual performance of the work (for all tests conducted including failed tests) and shall be preserved in good condition and order. These records shall be submitted in a complete Verification Boring Report to the Contracting Officer no later than 35 days following cutoff wall placement. The Contracting Officer may examine and review all such records at any time prior to their delivery, and may require changes to the record keeping procedure. During the coring operation, information shall be obtained about characteristics of the cutoff wall that may or may not be apparent from the core recovered from the hole. Observations of the drilling action must be made and reported to present as complete a picture, as possible of the consistency of the cutoff wall. When coring, the Contractor's quality control representative should note the amount of water return to the amount being injected through the drill rods. Careful observation of drill water return changes can indicate a potential defective zone. While the drill rod is rotating, the drill action and rate of penetration shall be noted and recorded. Changes in drilling rate can be related to changes in wall composition and provide complimentary data in areas of poor core recovery.

Basic information to be included on each core boring log should include:

a. Hole identifier, x and y coordinate of hole, top of work platform elevation, top of casing elevation, top of panel or element elevation, SECTION 02 32 00 Page 16 and if applicable, primary or secondary panel or element, panel or element number, or joint or overlap designation.

b. Herbert Hoover Dike alignment station reference and x, y coordinates.

c. Cutoff wall backfill or fresh grout mix designation.

d. Cutoff Wall Driller's name and Borehole Logger's name.

e. Make, size, and manufacturer's model designation of drilling Equipment, to include drilling rig type, drill rods, drill bits or core barrel and shoe type.

f. Type of drilling operation by depth.

g. Hole diameter.

h. Dates and time by depths when drilling operations were performed.

i. Time required for drilling each run.

j. Drill action, rotation speed, hydraulic pressure, water pressure, tool drops, and any other unusual and non-ordinary experience which could indicate the subsurface conditions encountered.

k. Depths at which samples or cores were recovered or attempts made to sample or core including top and bottom depth of each run.

l. Classification and description by depths of materials cored including composition, texture, presence and orientation of bedding, foliation, or fractures, presence of inclusions, and the RQD for each cored interval.

m. Percentage of sample or core recovered per run.

n. RQD of sample or core recovered per run.

o. Depth at which groundwater is encountered initially and when stabilized.

p. Depths at which drill water is lost and regained and amounts.

q. Depths at which the color of the drill water return changes.

r. Type and weight of drill fluid.

s. Depth of bottom of hole.

t. Unconfined compressive strength test results.

u. In-situ permeability test results.

v. Borehole orientation measured from top to bottom. Borehole orientation plotted within the wall panel/column as-built profile.

w. Color photographs of each core run with identification.

x. Anomalies, zones of varying quality, or cracks observed shall

SECTION 02 32 00 Page 17 annotated on the Drilling Logs along with a description of what was observed, the corresponding elevations, and the appropriate (N-S-E-W) field of view obtained using the optical televiewer.

-- End of Section --

SECTION 02 32 00 Page 18

Figure 1. Cutoff wall shape factor for borehole permeability test with long screened interval compared to hole diameter.

SECTION TABLE OF CONTENTS

DIVISION 35 - WATERWAY AND MARINE CONSTRUCTION

SECTION 35 41 17

JET GROUT CUTOFF WALL

PART 1 GENERAL

1.1 SCOPE OF WORK

1.2 REFERENCES

1.3 DEFINITIONS

1.3.1 Calibration Element

1.3.2 Continuous

1.3.3 Double Fluid Jet Grouting

1.3.4 Embankment

1.3.5 Existing Cutoff Wall

1.3.6 Foundation

1.3.7 Fresh-on-fresh Sequence (also referred to as wet-on-wet)

1.3.8 Homogeneous

1.3.9 Jet Grouting

1.3.10 Jet Grouting Contractor

1.3.11 Jet Grouting Parameters

1.3.12 Jet Grouting String

1.3.13 Jet Grout Supervisor

1.3.14 Jet Grout Waste

1.3.15 Jet Grout Waste Management

1.3.16 Jet Grout Waste Management Area

1.3.17 Jet Grout Waste Management Ditch

1.3.18 Jet Grout Cutoff Wall

1.3.19 Monitor

1.3.20 Native Soil/Rock

1.3.21 Pre-drilling

1.3.22 Pre-Splitting

1.3.23 Pre-jetting, Pre-cutting or Pre-washing

1.3.24 Primary-secondary Sequence

1.3.25 Production Work

1.3.26 Single Fluid Jet Grouting

1.3.27 Jet Grout Element (or Element)

1.3.28 Soil-cement

1.3.29 Jetting Specific Energy

1.3.30 Spoil Return

1.3.31 Triple Fluid Jet Grouting

1.3.32 Work Platform

1.4 JOB SITE CONDITIONS

1.4.1 Exploratory Borings and Subsurface Conditions

1.5 Contractor Responsibility

1.5.1 Probing to Verify Structure Footings

1.5.2 Supplemental Soil Explorations

1.5.3 Displacement Monitoring for Buried Pipes

1.5.4 Pre-construction and Post-construction Survey of Existing

Structures

1.6 PERFORMANCE REQUIREMENTS

1.7 SUBMITTALS

1.8 QUALIFICATIONS

SECTION 35 41 17 Page 1

1.8.1 Jet Grout Specialist

1.8.2 Jet Grout Project Manager

1.8.3 Jet Grout Supervisor

1.8.4 Jet Grout Drill Operator

1.9 QUALITY ASSURANCE

PART 2 PRODUCTS

2.1 EQUIPMENT

2.1.1 General

2.1.2 Pre-drilling Equipment

2.1.3 Drilling/Pre-Cutting Equipment

2.1.4 Jet Grouting Rods, Monitor, and High Pressure Hoses

2.1.5 Grout Batch Plant and High Pressure Pumping Equipment

2.1.6 Instruments for Drilling Deviation Measurements

2.1.7 Real Time Data Acquisition During Jet Grouting

2.2 MATERIALS

2.2.1 Cement

2.2.2 Ground Granulated Blast Furnace Slag

2.2.3 Drilling Fluids and Admixtures

2.2.4 Bentonite

2.2.5 Water

2.2.6 Material Storage Facility

PART 3 EXECUTION

3.1 GENERAL

3.2 PRE-PRODUCTION TRIAL PROGRAM

3.2.1 Pre-production Trial Program Location

3.2.2 Pre-production Trial Program Verification Testing

3.2.3 Pre-production Trial Program Results

3.3 CALIBRATION ELEMENTS

3.4 SITE PREPARATION

3.5 SURVEYS AND MARKERS

3.6 BURIED PIPE DISPLACEMENT RESPONSE VALUES

3.7 PRE-DRILLING, PRE-CUTTING, DRILLING AND JET GROUTING SEQUENCE

3.7.1 Horizontal and Vertical Alignment Tolerances

3.7.2 Drilling Deviation Measurements

3.8 ACCEPTANCE CRITERIA

3.8.1 In order for the Contracting Officer to assess compliance with

Performance Requirements:

3.8.2 Evaluating Compliance of the Cutoff Wall

3.9 CLEAN UP AND SITE RESTORATION

3.10 DISPOSAL OF WASTES

3.11 QUALITY CONTROL

3.11.1 Jet Grout Soil-Cement Samples

3.11.1.1 Fresh Cement Grout Density and Viscosity

3.11.1.2 Fresh Cement Grout Cube Tests

3.11.1.3 Jet Grout Cuttings Density and Viscosity

3.11.1.4 Bulk Samples of Jet Grout Cuttings

3.11.1.5 Unconfined Compressive Strength Testing on Hardened

Cuttings

3.11.1.6 Core Drilling and Cored Samples

3.11.2 Cutoff Wall Measurements

3.12 RECORDS

3.13 As-Built Profile

3.14 TREATMENT OF TOP OF CUTOFF WALL

3.15 Results

3.16 Construction Log

SECTION 35 41 17 Page 2

3.17 FIELD QUALITY CONTROL

-- End of Section Table of Contents --

SECTION 35 41 17 Page 3

SECTION 35 41 17

JET GROUT CUTOFF WALL

PART 1 GENERAL

1.1 SCOPE OF WORK

This section includes requirements for the jet grouting and related work as shown on the drawings and as specified herein. The Work consists of furnishing all plant, labor, equipment, materials, and of performing all operations required to construct the jet Grout cutoff walls (cutoff walls) that are consistent with the local geology and potential…