SHC24 AM0001 Revised Specs 35 20 23.pdf

Maintenance Dredging of NY Harbor, Sandy Hook Channel, NJ FNP SHC24

SECTION TABLE OF CONTENTS

DIVISION 35 - WATERWAY AND MARINE CONSTRUCTION

SECTION 35 20 23

DREDGING

08/20

PART 1 GENERAL

1.1 GENERAL INFORMATION

1.2 DEFINITIONS

1.2.1 Maintenance Material

1.2.2 New Work Material

1.2.3 Hard Material

1.2.4 Container and Transport Vessels

1.3 SUBMITTALS

1.4 METHOD OF COMMUNICATION

1.5 OTHER DREDGING OPERATIONS

1.6 ENVIRONMENTAL COMPLIANCE AND PROTECTION

1.7 BASIS FOR BIDS

PART 2 PRODUCTS

2.1 CHARACTER OF MATERIAL

PART 3 EXECUTION

3.1 INSPECTION

3.2 DREDGING

3.2.1 Order of Work

3.2.2 Interference with Navigation

3.2.3 Lights

3.2.4 Navigation Warnings

3.2.5 Ranges, Gages, and Lines

3.2.6 Dredge Plant and Equipment

3.2.7 Layout of Work

3.2.7.1 Overdepth Dredging

3.2.7.2 Side Slopes

3.2.8 Obstructions and Debris

3.2.9 Dredging Requirements

3.2.10 Quality Control

3.2.11 Surveys during Progress of Work

3.2.12 Salvaged Material

3.2.13 Safety of Structures

3.3 PLACEMENT OPERATONS

3.3.1 Placement of Excavated Materials

3.3.2 Charges for Material Placement

3.3.3 Misplaced Dredged Material

3.4 MEASUREMENT

3.4.1 Method of Measurement

3.4.2 Monthly Estimates

3.5 FINAL EXAMINATION AND ACCEPTANCE

3.6 PLANT REMOVAL

SECTION 35 20 23 Page 1

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SECTION 35 20 23 Page 2

SECTION 35 20 23

DREDGING

08/20

PART 1 GENERAL

1.1 GENERAL INFORMATION

This Section covers furnishing suitable dredging plant and performing all work required to remove the specified materials from within the prescribed work area limits as indicated, and placement of the dredge material within the prescribed material placement areas. The Contractor is responsible for making their own investigation of submerged, surface, and overhead structures in the work areas and other locations they find necessary to traverse. The exact location, depths, and heights of various structures including, but not limited to submarine cables, pipes, highlines, docks, piers, bulkheads, and bridges (as applicable), are not known and it will be necessary for the Contractor to ascertain interference problems and notify the respective owners in advance of dredging operations. The Contractor is responsible for making necessary arrangements with the respective owners of the structure(s) to assure satisfactory completion of dredging in the vicinity with a minimum interruption of service, and must perform their operations in such a manner as will avoid damage to these facilities.

1.2 DEFINITIONS

1.2.1 Maintenance Material

Maintenance material is defined as that comprising shoaling which has occurred since the channel areas were last dredged.

1.2.2 New Work Material

New work material is defined as previously undredged material.

1.2.3 Hard Material

Hard material is defined as material requiring blasting or the use of special equipment for economical removal, and includes boulders or fragments too large to be removed in one piece by the dredge.

1.2.4 Container and Transport Vessels

The term "container vessel" refers to any vessel used to contain, or hold, dredged material (scow, barge, hopper dredge, etc.). The term "transport vessel" refers to any vessel (tugboat, hopper dredge, work boat, etc.) used to move a container vessel. In the case of a hopper dredge, the hopper dredge may act as both a "container vessel" and a "transport vessel". If hopper dredge engines are not used for propulsion, and another vessel (tugboat, for example) is used to move it, then the hopper dredge would be the "container vessel" and the tugboat would be the "transport vessel".

Vessel Identification and Certification: All vessels (container and transport) that will be used, and/or may be used, during this contract must be identified prior to the first day of dredging. Vessels identified for

SECTION 35 20 23 Page 3 use on the contract must be certified to be fully operational, mechanically sound, completely seaworthy, and free of leaks or other defects.

1.3 SUBMITTALS

Government approval is required for submittals with a "G" or "S" classification. Submittals not having a "G" or "S" classification are for information only. When used, a code following the "G" classification identifies the office that will review the submittal for the Government.

Submit the following in accordance with Section 01 33 00 SUBMITTAL

PROCEDURES:

SD-02 Shop Drawings

Soundings or Sweepings ; G

1.4 METHOD OF COMMUNICATION

Provide a system of communication between the dredge crew and the crew at the placement / processing area. A portable two-way radio is acceptable.

1.5 OTHER DREDGING OPERATIONS

The Contractor should anticipate the possibility of concurrent dredging operations, adjacent to or nearby the dredge and placement areas in this contract. Delays should be anticipated in transiting to, and through, the placement sites during concurrent dredging and placement operations. As a standard safety precaution, observe all placement site specific restrictions pertaining to the limit of dredges operating within at any given time. Coordination with other dredge plant in the vicinity of the dredge and placement areas is required.

1.6 ENVIRONMENTAL COMPLIANCE AND PROTECTION

Comply with conditions and requirements of State or Federal permits. The Government will secure the permit for dredging and placement of material as indicated.

During the life of the contract, provide and maintain environmental protective measures. Also, environmental protective measures required to correct conditions, such as oil spills or debris, that occur during the dredging operations, must be provided. Comply with Federal, State, and local regulations pertaining to water, air, and noise pollution.

1.7 BASIS FOR BIDS

Payment will be at the contract unit price per cubic yard , multiplied by total cubic yards of acceptable dredging. Include a bid unit price per cubic yard of dredging based on the quantity as specified. If the Contracting Officer requires an increase or a decrease in total volume of dredging, the contract price will be adjusted in accordance with the FAR 52.211-18 Variation in Estimated Quantity. Dredging conditions specified and indicated describe conditions which are known. However, the Contractor is responsible for other conditions encountered which are not unusual when compared to conditions recognized in the dredging business as usual in dredging activities such as those required under this contract.

SECTION 35 20 23 Page 4

PART 2 PRODUCTS

2.1 CHARACTER OF MATERIAL

Based on sampling and testing of the proposed dredged material in 2017, the material to be removed consists of primarily, silt, sand, and clay:

a. 0.7% silt, 73.8% sand, and 25.5% gravel.

b. The Contractor is ultimately responsible for determination of the characteristics of materials to be dredged.

PART 3 EXECUTION

3.1 INSPECTION

Inspect the work, keep records of work performed, and ensure that gages, targets, ranges, and other markers are in place and usable for the intended purpose. Provide, at the request of the Contracting Officer, boats, boatmen, laborers, and materials necessary for inspecting, supervising, and surveying the work. When required, provide transportation for the Contracting Officer and inspectors to and from the placement area and between the dredging plant and adjacent points on shore.

3.2 DREDGING

3.2.1 Order of Work

The Contracting Officer will direct the Contractor on the order of work.

The Government reserves the right to change the order of work at any time.

3.2.2 Interference with Navigation

Minimize interference with the use of channels and passages. The Contractor is responsible for shifting or moving of dredges or the interruption of dredging operations to accommodate the movement of vessels and floating equipment, if necessary. Adhere to Coast Guard Regulations for passing vessels.

3.2.3 Lights

Each night, between sunset and sunrise and during periods of restricted visibility, provide lights for floating plants, pipelines, ranges, and markers. Also, provide lights for buoys that could endanger or obstruct navigation. When night work is in progress, maintain lights from sunset to sunrise for the observation of dredging operations. Lighting must conform to United States Coast Guard requirements for visibility and color.

3.2.4 Navigation Warnings

Furnish and maintain navigation warning signs along any pipelines.

Provide notice to increase public awareness of potential hazards presented by dredge plant equipment by stating the location, date of construction, equipment mooring, marshaling areas, using local newspapers, radios, television, waterway users associations, or other appropriate area specific communication networks. Ensure that an announcement is made through the same networks at the beginning of the dredging operation.

Make periodic updates/status announcements at intervals of not more than a month throughout the contract life.

SECTION 35 20 23 Page 5

3.2.5 Ranges, Gages, and Lines

Provide, set, and maintain ranges, buoys, and markers needed to define the work and to facilitate inspection. Establish and maintain gages in locations observable from each part of the work so that the depth may be determined. Suspend dredging when the gages or ranges cannot be seen or followed. The Contracting Officer will furnish, upon request by the Contractor, survey lines, points, and elevations necessary for the setting of ranges, gages, and buoys.

3.2.6 Dredge Plant and Equipment

Maintain all dredge plant and associated equipment such as, but not limited to, scows, coamings, barges, and pipelines, to meet the requirements of the work. Promptly repair leaks or breaks along pipelines. Remove any misplaced dredged material.

3.2.7 Layout of Work

The Contractor will be provided layout charts for all dredging areas based on the schedule of work, the Contractor's hydrosurvey requests, and/or the results of Government hydrographic survey monitoring. The most current Government hydrosurvey information will be displayed on the dredging layout charts and provided to the Contractor. Other pertinent information to be included with each layout package will be: payment method, required and maximum dredging depths, coordinates for the material placement site, distance one-way from dredging location to placement site, specific placement site instructions, supplemental tide gauge information, horizontal control locations, and computed hydrosurvey quantities.

The total estimated quantity of material to be removed is computed as that material that is within the specified limits, including side slopes and overdepth. The quantities listed are estimates only. All estimated quantities are subject to FAR 52.211-18 Variation in Estimated Quantity.

3.2.7.1 Overdepth Dredging

To cover unavoidable inaccuracies of dredging processes, material actually removed to a depth of two (2) feet below the required depth specified and within the dredging limits will be measured and paid for at full contract price. The quantity of overdepth dredging is based on the contour dredging method where payment is allowed for all metial up to Overdepth Grade except below project grade on side slopes.

3.2.7.2 Side Slopes

Side slopes in the dredge areas within this contract will be measured and paid based on a 3 feet horizontal to 1 foot vertical ratio. Dredging on side slopes must follow, as closely as practicable, the dredge area limits indicated on associated layout drawings.

A 2 foot allowance will be made for dredging beyond the indicated or specified side slopes, except as provided herein. The allowance will be determined by projecting a line upwards, paralleling the project design side slopes, from the intersection of the overdepth dredging limit (at a point located vertically below the limit of dredging at the top of slope). The amount of material excavated from side slopes will be determined by either cross-sections or computer, or both.

SECTION 35 20 23 Page 6

3.2.8 Obstructions and Debris

Except as indicated, the Government has no knowledge of cables, pipes, or other artificial obstructions or of any wrecks, wreckage, or other material that would necessitate the use of explosives or the employment of additional equipment for economical removal. Contractors should however exercise due diligence in determining the existence of any obstructions within proposed work areas during bid preparation.

Trash, debris and other miscellaneous man-made and natural organic objects may be encountered during the course of the dredging. This material may be present at any location above the required depth as indicated on drawings.

Man-made materials may include (but are not limited to) wood, sheet metal, glass, lumber, plastics, tires, hoses, chains, cables, and hawsers and abandoned steel pipes. Natural organic objects include wooden objects such as tree branches but does not include inorganic objects such as large boulders.

3.2.9 Dredging Requirements

Dredge Areas

1) BASIC WORK: requires dredging to the plane of -35 feet MLLW plus 2 foot allowable overdepth.

3) OPTION 1: requires dredging to the plane of -35 feet MLLW plus 2 foot allowable overdepth.

4) OPTION 2: requires dredging to the plane of -35 feet MLLW plus 2 foot allowable overdepth.

Placement Area

Material is to be placed at the Sea Bright Offshore Borrow Area (SBOBA).

See Section 01 20 00 PRICE AND PAYMENT PROCEDURES for more details.

3.2.10 Quality Control

Establish and maintain quality control for operations to assure compliance with contractual requirements and maintain records of this quality control for dredging operations.

While performing all dredging work control the horizontal positioning of the dredge with electronic positioning.

3.2.11 Surveys during Progress of Work

Quality of dredging depth will be determined by soundings or sweepings taken behind the dredge as work progresses. The Contractor will take progress soundings or sweepings. The Contractor will submit all data files and survey information, including mapping of these surveys to the COR for their review.

3.2.12 Salvaged Material

Anchors, chains, firearms, and other articles of value, which are brought to the surface during dredging operations, must remain or become the

SECTION 35 20 23 Page 7 property of the Government and will be placed on shore at a convenient location near the site of the work, as directed.

3.2.13 Safety of Structures

The prosecution of work must ensure the stability of piers, bulkheads, and other structures lying on or adjacent to the site of the work, insofar as structures may be jeopardized by dredging operations. Repair damage resulting from dredging operations is the responsibility of the Contractor, insofar as such damage may be caused by variation in locations or depth of dredging, or both, from that indicated or permitted under the contract. The Contractor is responsible for coordinating with the owner of the structure for any necessary repairs.

3.3 PLACEMENT OPERATONS

3.3.1 Placement of Excavated Materials

Provide for safe transportation and placement of dredged materials. The placement of dredged materials in unauthorized places is forbidden. Comply with rules and regulations of all, federal, state and local authorities.

3.3.2 Charges for Material Placement

The Contractor is responsible for payment of any charges imposed by the state-permitted, contractor-furnished placement site.

3.3.3 Misplaced Dredged Material

Any dredged materials deposited at locations other than in areas designated or approved by the Contracting Officer will be considered misplaced material and will not be paid for until the Contractor, at his own expense, removes and deposits such misplaced material where directed.

This required removal and redeposit of the misplaced material and any necessary placement site restoration work is not the basis for a time extension or additional compensation under this contract.

The Contractor will immediately notify the Contracting Officer or his Representative if any material is misplaced or when infill or shoaling beyond the Contractor's control occurs.

3.4 MEASUREMENT

The Government will take soundings before and after dredging. The government will perform a before-dredge (BD) survey of the entire work area prior to the commencement of work. Once complete and the contractor has submitted a complete survey of the entire dredge area along with all associated files, the government will perform an after-dredge (AD) survey of the same area. The material removed between these two surveys within the allowable footprint and up to the maximum dredge template will be computed. This computation will be made using the TIN method.

Final quantities will be subject to deductions or correction of deductions previously made because of excessive overdepth, dredging outside or authorized areas, or placement of material in an unauthorized manner.

3.4.1 Method of Measurement

Quantity of material removed that will be paid for will be measured by

SECTION 35 20 23 Page 8 cubic yard in place by means of volume difference from soundings taken before and after dredging. The drawings represent existing conditions based on current available information, but will be verified and corrected, if necessary, by soundings taken before dredging in each locality.

3.4.2 Monthly Estimates

Monthly estimates of work completed will be based on the result of soundings taken during the progress of the work. Deductions will be made for dredging and placement not in accordance with the specifications.

3.5 FINAL EXAMINATION AND ACCEPTANCE

As soon as practicable after the completion of areas, which in the opinion of the Contracting Officer, will not be affected by further dredging operations, each area will be examined by the Government by sounding or sweeping, or both. Remove shoals and lumps as required by methods approved by the Government. However, if the bottom is soft and the shoal areas form no material obstruction to navigation, removal may be waived at the discretion of the Government. The Contractor will be notified when soundings or sweepings are to be made. When areas are found to be in a satisfactory condition, the work therein will be accepted as complete.

Re-dredging at the Contract price, within the limit of available funds, may be completed with the consent of both the Government and the Contractor when infill or shoaling beyond the Contractor's control occurs in any area previously accepted.

This contract has no partial acceptance areas. Any survey related disagreement(s) as it pertains to this contract must be submitted in writing to the Contracting Officer or his representative within 5 business days of occurrence of such survey related event. Failure to notify the Contracting Officer or his representative within 5 business days of such survey related event disqualifies the Contractor from any such related claims.

3.6 PLANT REMOVAL

Upon completion of the work, the contractor shall remove all dredging plant, including ranges, buoys, piles, and other markers or obstructions.

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SECTION 35 20 23 Page 9