31 24 00.00 18.pdf

FIMP Contract 1 FIMPCT1

100% SPECIFICATIONS - RTA AMENDMENT 3

SECTION 31 24 00.00 18

BEACH FILL PLACEMENT

PART 1 GENERAL

1.1 MOBILIZATION AND DEMOBILIZATION

Mobilization must include all costs for operations accomplished prior to commencement of actual dredging operations, such as transfer of dredge and attendant plant and equipment to site, initial installations of pipe, preparation of beach fill areas, and other incidentals in advance of the actual dredging. Demobilization must include general preparation for transfer of plant to home base, removal of pipelines, cleanup of beach fill areas, and transfer of plant to its home base. The cost of work other than mobilization and demobilization of the Contractor's dredging plant and equipment must not be included in this item. For payment for Mobilization and Demobilization see contract clause Section 00 72 00 Contract Clauses.

All costs connected with the mobilization and demobilization of all of the contractor's dredging plant and equipment will be paid for at the contract lump sum price for this item. 60 percent of the lump sum price will be paid to the Contractor upon completion of his mobilization to the work site. The remaining 40 percent will be included in the final payment for work under this contract.

In the event the Contracting Officer and/or his Representative considers that the amount in this item 60 percent, which represents mobilization, does not bear a reasonable relation to the cost of the work in this contract, the Contracting Officer and/or his Representative may require the Contractor to justify this portion of the bid. Failure to justify such price to the satisfaction of the Contracting Officer and/or his Representative will result in payment of actual mobilization costs as determined by the Contracting Officer and/or his Representative, at the completion of mobilization and payment of the remainder of this item in the final payment under this contract. The determination of the Contracting Officer and/or his Representative is not subject to appeal.

1.2 DREDGING OF BORROW AREAS

The beach placement to be done under these specifications will be the dredging of the Fire Island Inlet channel, deposition basin and ebb shoal, with placement of the dredged sand along the shoreline, as shown on the contract drawings.

1.3 SCOPE

The work covered by this section consists of furnishing all labor, materials, and equipment, and performing all operations required for removal of material from the designated areas as shown on the contract drawing, conducting pre-and post-removal surveys of the channel, deposition basin and ebb shoal, transportation and placing the material as beach fill on the Atlantic Ocean shore within the limits specified herein and shown on the drawings, conducting pre- and post-placement beach condition surveys and grab samples GSD analysis as specified.

SECTION 31 24 00.00 18 Page 1

1.4 SITE CONDITIONS

Bidders are expected to examine the site of the work, including the placement areas and decide for themselves the conditions affecting their operations prior to submitting their bids. See Contract Clause entitled:

"SITE INVESTIGATION AND CONDITIONS AFFECTING THE WORK" (FAR 52.236-3).

1.5 SEDIMENTATION PERMITS

No local governmental sedimentation or erosion control permits are required for this work except that as required in accordance with Contract Clause entitled: "PERMITS AND RESPONSIBILITIES" (FAR 52.236 7). Refer to Water Quality Certificate (WQC) for project's requirements.

1.6 SUBMITTALS

The Contractor must submit for approval, by the Contracting Officer and/or his Representative, his plan for development of any contractor-furnished placement areas or any modification to the Government furnished placement area. This plan must show areas or portions thereof to be used. The plan must also show the manner in which the dredged material will be distributed in the areas. Such plans must be provided by the contractor at the Preconstruction Conference. If the plan is not accepted the Contractor is to perform the work in accordance with the specifications.

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 must be submitted in accordance with Section 01 33 00 SUBITTAL PROCEDURES:

SD-03 Product Data

Grain Size Distribution Curves of beach fill material after placement ; G, DO

SD-11 Closeout Submittals

Before and After Beach Fill Placement Surveys ; G, RO

Before and After Dredge Surveys of the Borrow Area ; G, RO

Weekly Borrow Area Surveys per paragraph INITIAL AND FINAL SURVEYS

1.7 QUALITY CONTROL

a. QUALITY CONTROL: The Contractor must establish and maintain quality control for material placement to assure compliance with contract requirements, and maintain records of his quality control for all construction operations, including but not limited to the following:

1) Dredging, including suitability of dredged material and manipulation and control of the dredge discharge.

2) Placement of sand fill material, including continuity and order of placement; distribution of material and measures used to control loss of material.

SECTION 31 24 00.00 18 Page 2

b. The Contractor will have a "NOTICE TO MARINERS" published by the Coast Guard 15 days prior to start of work.

c. Placement Plan: The Contractor must submit for approval his placement plan at the Preconstruction Conference (Section 01 30 00 ADMINISTRATIVE REQUIREMENTS). The placement plan must include the particular site(s) to be utilized, all special conditions (i.e., NYSDEC, etc.) specific to sites(s) being used, contractor access to the site(s) locations and cross-section of existing and proposed dikes, maximum elevations and quantities of placement material for each site, weir and drainage structure locations, manner in which the dredged material will be distributed in the areas, etc. Approval of the placement plan by the Contracting Officer or his representative is required prior to placement site(s) preparation. The Contractor must conduct his work in accordance with the Placement Plan, however, approval of the plan for development of the placement area does not in any manner relieve the Contractor of his responsibility for the adequacy of the design and construction and drainage facilities required. In addition, the Contractor must also submit at the pre-construction meeting, his plan for road crossings of the discharge pipeline. The contractor must be responsible for securing the appropriate permits for any road crossings of discharge pipeline or similar activities and may not begin work until such permits are received from the appropriate agencies.

d. Pre-Construction Site Visit: Prior to actual construction of any placement site, the Contractor and the Contracting Officer and/or his representatives must visit the site(s) for the purpose of delineating areas of access avoidance (cultural resource, protection of existing dune, and/or wetland concerns).

e. Construction/Maintenance of Containment Structure. The Contractor must construct all retaining dikes, waste weirs and drainage structures as are necessary for confining the dredged material and for controlling placement area effluent until acceptance of all work under the contract.

f. Protection of Structures and Adjacent Areas. The contractor must be responsible for the maintenance, repair and stability of all dikes, roads and structures, used by him under the contract. The Contractor must restore all dikes, roads, and areas he disturbs through his operations to a satisfactory condition, as approved by the Contracting Officer or his representative, at no additional cost to the Government.

g. Protection of Existing Dunes and Dune Vegetation: Existing dunes and dune vegetation must be undisturbed to the maximum extent practicable.

Limits of existing dune and dune vegetation must be identified and delineated prior to fill placement. Pipelines and access for construction equipment must not cross existing dunes or dune vegetation except as directed by the Contracting Officer.

h. Inspection of Structures and Adjacent Areas. The Contractor must inspect all dikes, roads, waste weirs, and adjacent areas utilized during this operation on a daily basis to assure their safety and stability. The Contractor must include these inspections in his daily quality control report. The inspection must include but not be limited to structures, equipment, safety, security, drainage and seepage.

i. Reporting Requirements. The Contractor must maintain a daily written record of all placement site operations. This requirement must be made a part of the Contractor's Quality Control Plan and each record must be

SECTION 31 24 00.00 18 Page 3 included in the Contractor's Quality Control Report.

j. Containment Structure Restoration. The Contractor must restore any feature of any containment structures as required to prevent the escape of dredged material from the placement site on to adjacent areas.

k. Control of Placement Area Effluent. The contractor must monitor and control placement area conditions and placement effluent quality as prescribed in these specifications. The Contractor's Quality control Plan must identify monitoring requirements and measures, which will be taken to control placement area conditions to insure effluent quality meets the requirements identified in the Water Quality Certificates (Section 00 90 02 Water Quality Certificate).

l. New York State Water Quality Certifications. The contractor must comply with all requirements identified in the NYSDEC Water Quality Certificate (WQC) including all special conditions. A copy of the WQC is included in Section 00 90 02 WATER QUALITY CERTIFICATE J, Attachment E of this specification.

m. Removal of Containment Area Structures. Any structures (i.e., weirs, pipeline, etc.) installed by the Contractor for use in his placement operations must be removed and the contractor must repair and stabilize all areas affected by the removal of these structures as approved by the Contracting Officer.

n. The contractor must obtain grab samples of the placed fill from: the beach backshore; edge of berm; mean high water (MHW); and mean low water (MLW). One set of samples must be taken every 200 feet along the placed fill area. A grain size analysis of each sand sample will be made using sieve sizes comparable to the Wentworth size classifications (shown in Section 00 90 04 WENTWORTH SCALE) and the results plotted on an appropriate curve format. The laboratory analysis results and plotted grain size distribution curves must be furnished with the Daily Construction Quality Reports.

o. The contractor must obtain a minimum of three (3) grab samples from the channel, three (3) from the eastern deposition basin, and three (3) from the ebb shoal area. Samples must be spaced throughout these areas, and locations must be provided along with grain size analysis. A grain size analysis of each sand sample will be made using sieve sizes comparable to the Wentworth size classifications (shown in Section 00 90 04 WENTWORTH SCALE) and the results plotted on an appropriate curve format. The laboratory analysis results and plotted grain size distribution curves must be furnished with the Daily Construction Quality Reports.

1.8 REPORTING REQUIREMENTS

1.8.1 Daily Report of Operations

The Contractor will, on Eng. Form 4267, be required to prepare and maintain a daily report of operations and inspections and furnish copies thereof to the Contracting Officer or his representative. All the forms prescribed for the required information are in Section 00 90 01 Report of Operations Form. Further instructions on the preparation of the report will be furnished at a pre-construction conference. Attached to the form, the Contractor must submit a plan of the borrow area indicating the location, depth and extent of his dredging operations for that day.

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1.8.2 Dredge Operation Production Records

When a hopper dredge operation is used, the Contractor will submit daily records of hopper loads, including tonnages of empty and fully loaded conditions prior to pumpout. For all types of dredge operations the Contractor will furnish production meter records (using properly calibrated instruments) of suctionline densities and pipeline velocities.

Production meter records and loadmeter records must be cataloged either by time of day or load number.

PART 2 PRODUCTS

2.1 CHARACTER OF MATERIALS

The character of materials within the borrow areas is provided in Section 00 90 03 Composite Grain Size Distribution Curves and Grain Size Scales for Sand Sediments. If rock, rubble, or any other debris is encountered during dredging, the Contractor must immediately cease operations and report to the Contracting Officer's Representative (COR). He must report the encounter with the rock, rubble or any other debris on the quality control form and immediately notify the Contracting Officer, or his representative, verbally, providing location in Long Island Lambert coordinates of the area of rock, rubble or any other debris. Rock, rubble, or any debris larger than two (2) inches in diameter which is excavated and placed on the beach will be removed by the Contractor, totally at his own cost. If the Contractor fails to remove the rock, rubble, or any other debris, such material may be removed by the Government and the cost of such removal may be deducted from the money due, or to become due to the Contractor or may be recovered under his bond. Bidders are expected to examine the site of the work and boring samples and decide for themselves the character of the materials.

2.2 DREDGING AREAS

2.2.1 Quantity

2.2.1.1 Fire Island Inlet Channel, Deposition Basin and Ebb shoal

For this project, a sufficient quantity of material suitable for the beach fill is available from the channel, deposition basin and ebb shoal as shown on the Contract Drawings.

2.2.2 Borrow Area Limits

All material must be dredged from the channel, deposition basins and ebb shoal, refer to section 01 14 00 for order of work. In the event any portion of the dredging areas yields material unsuitable for use on the beach, the Contracting Officer, or his representative, may direct that the depth of excavation be changed or that the excavating equipment be moved to other portions of the dredging areas that will yield suitable material.

Under no circumstances must material be obtained from outside the established limits of the dredging areas. Should it be determined that an area outside the limits of the designated dredging areas was used for borrow, the Contractor must restore such area to original condition.

2.2.3 Soundings

Soundings in the dredging area are shown on the drawings. Dredging in the dredging areas will be allowed to the depths indicated on the drawings.

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2.2.4 Slopes

The dredge cuts in the dredging area must not have side slopes steeper than 1 on 3. Dredging area must have a uniform bottom elevation.

2.3 GRAIN SIZE DISTRIBUTION CURVES

2.3.1 After Placement

Submit the Grain Size Distribution Curves of beach fill material after placement to the Contracting Officer for approval.

PART 3 EXECUTION

3.1 ORDER OF WORK

Refer to section 01 14 00 WORK RESTRICTION, "Order of Work" paragraph, and see Section 35 20 23 DREDGING.

3.2 PLACEMENT OF SAND FILL

3.2.1 Placement

The material dredged from the designated borrow areas must be placed on the beach fill areas to the specified limits and cross sections shown on the drawings, provided, however, that the provisions of subparagraph 3.2.8(4) must be controlling with respect to the limits and sections of the beach fill area below El. +3.0 NAVD. The material must be deposited as evenly as practicable by the hydraulic method to form a comparatively smooth and uniform beach surface. A tolerance of 0.5 foot above El. +3.0 NAVD, measured vertically, will be allowed and paid for on material placed above the required design grades.

3.2.2 Material Deposited Elsewhere

Any material that is placed elsewhere than in places designated or approved by the Contracting Officer, or his representative, will not be paid for, and the Contractor may be required to remove such material, and place it where directed, at his expense.

3.2.3 Dredge Material

Dredge material must be pumped directly from the dredging vessel to the beach placement area. No bottom placement and re-handling will be allowed.

Dredge discharge must be manipulated and controlled by the Contractor in such a manner that a minimum of shaping by mechanical equipment will be required and a minimum amount of material will be lost.

3.2.4 Floatable Material

All floatable material excavated, including, without limitation, wood and tires, must be disposed of at an existing approved upland disposal area.

Should the Contractor encounter floatable material, a copy of a letter granting the permission of appropriate authorities to use an existing approved upland disposal area must be submitted to the Contracting Officer and/or his representative.

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3.2.5 Final Beach Berm

The final beach berm of placed fill must be shaped above El. +3.0 ft NAVD by bulldozing or other approved means as required, to provide the design beach sections shown on the drawings. No reshaping of the existing beach, which is above the lines and grades of the design section will be permitted. Return Staging area and access roads to their original conditions.

3.2.6 Compensated Slope

If the construction template cannot be achieved at the toe of the section, then a compensated slope to offset voids in the construction fill template will be allowed. Such excess material must be placed below elevation +8.5 ft NAVD and graded at the design slope to +3.0 ft NAVD with all material below +3.0 ft NAVD being the uncontrolled hydraulic slope of the material;

and the payable quantity must not exceed the deficiency in template volume plus tolerance.

3.2.6.1 Acceptance of Fill Section

A fill section will not be accepted unless the payable quantity equals or exceeds the cross sectional volume between the design grade and the pre-existing grades (excludes tolerance).

3.2.7 Dredge Discharge

It is intended that dredge discharge must be manipulated and controlled by the Contractor in such a manner that a minimum of shaping by mechanical equipment will be required and a minimum amount of material will be lost.

3.2.8 Placement of Dredged Material

Placement of dredged material on the beach fill area must be subject to the following conditions:

(1) Any discharge pipeline crossing navigation channels must be submerged so that sufficient depth for navigation exists.

(2) Such discharge pipeline must be marked by signs, lights or other devices to insure safety to navigation by day and by night. All of these devices must be in complete accordance with Coast Guard regulations. The contractor must provide a written discussion of pipeline markings in the Accident Prevention Plan. Refer to section 01 35 26 GOVERNMENTAL SAFETY REQUIREMENTS for the Accident Prevention Plan requirements.

(3) The discharge pipeline must be arranged as approved by the Contracting Officer or his representative.

(4) It is expected that in placing the sand fill hydraulically, most of the silt and other fines being pumped will be washed into the ocean and dissipated by wave action. Ponding of the dredge effluent will not be allowed. However, baffles or dikes to control the flow of the dredge effluent will be required. The final seaward slope of the sand fill to be placed below El. +3.0 ft NAVD must be the uncontrolled hydraulic slope of the material placed by the dredging process, estimated to be a 1 vertical to 15 horizontal slope down to the ocean bottom. The dredge effluent must in all cases return directly to the

SECTION 31 24 00.00 18 Page 7 ocean and not to the inshore side of the fill.

(5) A dike must be constructed at the inshore limit of fill to prevent the dredge effluent from extending beyond the contract limits.

(6) Tracked vehicles must be operated on the fill in such manner so that they do not cause excessive gouging.

(7) The Contractor must be solely responsible for any damage caused by him to any boardwalk, structures, existing dune or dune vegetation, pavement, curbs, signs, lamps, bulkhead, seawall, groin, beach grass, or any other property adjacent to the beach fill areas, and must be required to repair at his own expense any such damage caused during the performance of work under this contract. Prior to the commencement of operations and after completion thereof, a joint inspection by representatives of the Contractor, The Contracting Officer and local interests pertaining to the above will be made.

(8) In order to provide access for pedestrians across the pipeline in beach use areas within the contract limits, the pipeline must be ramped with sand on both sides at a 1V:10H slope over the top elevation of the pipe at pedestrian access ways or at 500-foot intervals. Width of the ramps must be 10 feet. The Contractor may provide another method of maintaining pedestrian thoroughfare across the pipe-line upon approval by the Contracting Officer or his representative. Pedestrian thoroughfare must be maintained for the duration of the contract. Also, in order to provide for the safety of persons using the beach, Points of Contact are listed in Section

01 30 00 ADMINISTRATIVE REQUIREMENTS.

During all pumping operations, the Contractor must provide personnel to maintain visual control at the end of the discharge line. Radio contact must also be provided by the Contractor to enable such personnel to halt dredging in case of emergency.

(9) The Contractor may be directed to move to another location within the Dredging Area if undesirable material begins to be pumped onto the beach (i.e. silt).

(10) The area where filling operations are in progress must be floodlighted during the hours of darkness. Illumination must be provided by using portable light equipment such as model No.LDA I6 MTVE manufactured by ALLMAND BROS. INC. of HOLDREIRE, or approved equal. A minimum of 3-foot candles of illumination must be maintained in the immediate vicinity of the pipe discharge.

(11) Monitoring the discharge operation by radio communication from the discharge location to the leverman during all pumping operations is required.

(12) A placement section will not be accepted for final survey unless the section is graded and dressed so as to eliminate any undrained pockets, abrupt lumps, and depressions in the beach fill surface.

(13) During all pumping operations, the Contractor must provide personnel to maintain visual control of the end of the discharge line. Radio contact must also be provided by the Contractor to enable such personnel to halt dredging in case of emergencies or undesirable material placement as directed by the COE.

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(14) A temporary dike must be constructed at the inshore limit of the fill to prevent the dredging effluent from extending beyond the contract limits.

(15) Completed work on the beach fill placement will be accepted in 500-foot long sections. Upon completion of all filling operations within an acceptance section, the fill must be graded and dressed so as to eliminate any un-drained pockets, abrupt lumps, and depressions in the beach fill surfaces. The bank caused by ocean wave erosion must be graded down to a slope not steeper than one (1) foot vertical to twenty (20) feet horizontal to Elev. +3.0 NAVD. Final surveys as required in paragraph entitled QUANTITY SURVEYS of the Special Contract Requirements may not be performed until fill is graded and dressed. Final acceptance of the beach fill work will be as defined in paragraph entitled FINAL EXAMINATION AND ACCEPTANCE in section 01 30 00

ADMINISTRATIVE REQUIREMENTS.

(16) The Contractor must obtain grab samples of placed fill from: the beach back-shore; edge of berm; mean high water (MHW); and mean low water (MLW). One set of samples must be taken every 200 feet along the placed fill area. A grain size analysis of each sand sample will be made using sieve sizes comparable to the Wentworth size classifications (shown on Section 00 90 04 WENTWORTH SCALE) and the results plotted on the curve format in section 00 90 03 Composite Grain Size Distribution Curves and Grain Size Scales for Sand Sediments. The laboratory analysis results and plotted grain size distribution curves must be furnished with the Daily Construction Quality Reports.

3.3 PLANT

The Contractor agrees to keep on the job sufficient plant to meet the requirements of the work. The plant must be in a satisfactory operating condition and capable of safely and efficiently performing the work as set forth in the specifications. The plant must be subject to the inspection of the Contracting Officer and/or his Representative at all times. No reduction in the capacity of the plant employed on the work must be made except by written permission of the Contracting Officer and/or his Representative. The measure of the "capacity of the plant" must be its actual performance on the work to which these specifications apply.

3.3.1 Scows

The use of scows is prohibited.

3.3.2 Hydraulic Pipelines

All pipelines for hydraulic dredging Plant must be kept in good condition at all times and any leaks or breaks along their length must be promptly repaired. All breaks in any pipeline must be reported on the Contractor's Daily Quality Control Report for the date the break occurred. An estimation of the duration of the break and the quantity of misplaced material must be provided in the report.

3.3.3 Marking of Floating Dredge Pipelines

The contractor must be required to mark floating dredge pipelines in accordance with the requirements of 88.15 of Annex V of U.S. Navigation

SECTION 31 24 00.00 18 Page 9

Rules, inland, COMDTINST M 16672.2A, dated 23 December 1983. Dredge pipelines that are floating or supported on trestles must display one row of yellow lights, visible all around the horizon for at least 2 miles on a clear, dark night. The lights must flash at 50 or 70 times per minute and be places not less than 1 and not more than 3-5 meters (9.8 - 16 feet) above the water. The lights must be sufficient in number to clearly show the length and course of the pipeline.

3.3.4 Dredge Pipelines Crossing Navigable Channels

The arrangement of any pipeline crossing a navigable channel must be approved by the Contracting Officer. Where the pipeline crosses a navigable channel the spacing of the lights must not be more than 10 meters (33 feet) apart. Two red lights, visible all around the horizon for at least 2 miles on a clear, dark night, must be displayed at each end of the pipeline, including the ends in a channel where the pipeline is separated to allow vessels to pass (whether open or closed). The lights must be one meter (3.3 feet) apart in a vertical line with the lower light at the same height above the water as the flashing yellow light.

3.3.5 Submerged Pipelines

Any discharge pipeline submerged to cross a navigation channel must be submerged so that sufficient depth for navigation exists. Such discharge pipeline must be marked by signs, lights or other devices to insure safety to navigation by day and by night. All of these devices must be in complete accordance with Coast Guard regulations.

3.3.6 Road Crossings

A detailed plan of the pipeline route to be used by the Contractor must be submitted prior to laying of the pipeline. A ramp over any discharge pipeline crossing any roadways at the project site(s) must be provided.

Additionally, adequate signs (caution and stop, if necessary), and flashing warning lights, must be provided by the contractor to ensure safety to vehicles and their occupants using the roadway. Under no circumstances must any portion of the paved portion of any roadway be disturbed. If the roadway is disturbed, the Contractor must provide an adequate base to allow traffic to pass over the pipeline, and repairs to the roadway after completion of the project area, such that the roadway is restored to a condition equal to or better than the condition prior to disturbance. In addition, prior to placement of the pipeline across any roadway, the Contractor must contact personnel at the appropriate municipality to determine if the warning signs and lights are adequate for safety purposes.

3.3.7 Towing Vessels

A sufficient number of vessels of adequate size and horsepower, each designed, outfitted, and equipped for towing service, must be available at all times to move both self- and non-self propelled plant against tides, current, and winds during severe weather conditions.

3.4 DREDGE LOCATION CONTROL

The Contractor is required to have electronic positioning equipment that will accurately compute and plot the position of the dredge. Whenever dredging operations are underway, the location of the dredge must be continuously monitored and the dredge location, in Long Island Lambert

SECTION 31 24 00.00 18 Page 10

Coordinates, must be recorded at intervals not to exceed one (1) minute.

Such records, and an accurate map showing actual dredging locations, must be furnished to the Contracting Officer, or his representative daily as part of the Quality Control Reports. The electronic positioning equipment must be installed on the dredge so as to monitor, as closely as possible, the actual location of the cutterhead or dragarm. This equipment must be continuously accessible by the Government representative on board the dredge, who must be able to verify equipment calibration at any time. The electronic positioning equipment must be required to be calibrated monthly, maintained and operated so that the maximum error for the coordinates recorded do not exceed 3 feet. The location on the dredge of the master antenna and the distance and direction from the master antenna to the cutterhead must be reported on the Quality Control Reports. No dredging will take place outside the borrow area limits as shown on the drawings. Dredging outside of the borrow area limits will result in immediate shutdown of work. The Contractor's methods of location of the dredge must be submitted with the quality control plan. Information to be submitted must include a written description of the equipment, including applicable manufacturers brochure and data, and previous jobs on which the equipment has been used.

3.4.1 Dredging Depth Monitoring Equipment

The Contractor must have in continuous operation whenever dredging operations are underway, electronic equipment which measures the cutterhead or dragarm depth. The depth measuring device (as approved by the Contracting Officer or Contracting Officer Representative) must be used and interfaced with the electronic positioning equipment required in Paragraph 3.4. The depth measuring device must be calibrated by a bar check daily. This equipment must be accessible to the Government Representative onboard the dredge, who must be able to verify calibration.

Vertical accuracy must be + or -0.1 foot. Records required for dredge location (Paragraph 3.4) must also include depth corrected for tide (elevation reference to MLW). Details of the depth measuring device must be submitted with the quality control plan.

3.5 NOTIFICATION OF ON-SHORE BARGE OPERATION

A minimum of one hour's notice must be furnished by the Contractor to the Contracting Officer, or his representative, and concurrently to the municipal or local agency responsible for beach operations prior to a barge coming on shore between the hours of 9 AM and 7 PM. Barges will not be allowed to come on shore on weekends or State holidays between the hours 9 AM and 7 PM. At no time will a barge be allowed to come on shore in an area other than the immediate work area.

3.6 BUOY REMOVAL

The Contractor must notify the Coast Guard at least 15 days prior to the date desired for having buoys removed or relocated which interfere with dredging operations. Requests must be made in writing to:

COMMANDER (OAN)

FIRST COAST GUARD DISTRICT

408 ATLANTIC AVENUE

BOSTON, MASS. 02110

or by telephoning (617) 223 8337

SECTION 31 24 00.00 18 Page 11

3.7 TEMPORARY FENCES

3.7.1 Land Booster Pumps

If land booster pumps are used, a temporary Polyethylene Mesh Safety fence must be installed by the Contractor around the booster facility. For fence construction, refer to section 01 50 00 TEMPORARY CONSTRUCTION FACILITIES AND CONTROLS, "Polyethylene Mesh Safety Fencing" paragraph.

The Contractor must remove the fence at the completion of the work or when directed by the Contracting Officer, and all material used must remain property of the Contractor.

3.7.2 Beach Access

Beach access ramps and stairs to the work areas within 500 ft of the designated work area must be closed by the contractor by erection of a minimum 4 feet high Polyethylene Mesh Safety fence. For fence construction refer to section 01 50 00 TEMPORARY CONSTRUCTION FACILITIES AND CONTROLS, "Polyethylene Mesh Safety Fencing" paragraph.

The Contractor must also provide signage at the beach access points indicating "DO NOT ENTER - CONSTRUCTION AREA", as approved by the Contracting Officer.

Ramps, stairs, or other access features requiring closure will be identified during on-site pre-construction meeting between the Corps of Engineers, the Contractor, and local interests.

3.7.3 Sand Fence

Sand fence will be installed on the beach enclosing the 1000-foot long designated work section from the backshore limit of fill to the mean high water line. The fence must also be installed along the backshore to prevent entry to the work area. The fencing material for this purpose must be a minimum 4 feet high Polyethylene Mesh Safety fence. For fence construction, refer to section 01 50 00 TEMPORARY CONSTRUCTION FACILITIES AND CONTROLS, "Polyethylene Mesh Safety Fencing" paragraph. Contractor must provide adequate security personnel to restrict unauthorized entry into the work area during all times of operation. The ends of each work area must be closed off during work in that area by erection of a sand fence extending from the landward limit of fill seaward to the mean high water line.

The ends of each work area must be closed off during work in that area by erection of a sand fence extending from dune road seaward to the mean high water line.

3.7.4 Removal of Temporary Fencing

The fence must be removed by the Contractor at the completion of the work or when directed by the Contracting Officer, or his representative, and all material used must remain the property of the Contractor.

For measurement and payment of temporary fences refer to Section

01 22 00.00 10 PRICE AND PAYMENT PROCEDURES.

3.8 SECURITY OF WORK AREA

In the work area provide a combination of fencing above the high water

SECTION 31 24 00.00 18 Page 12 line securing the north, west and east sides of the work area and a warning tape to the low water line. Place signs indicating "No Trespassing- Construction Area" on the fence every 50 feet of length.

3.9 SURVEY RECORDS

3.9.1 Beach Fill Placement Surveys

Submit the Before and After Beach Fill Placement Surveys for Contracting Officer's approval.

3.9.2 Dredge Surveys of the Borrow Area

Submit the Before and After Dredge Surveys of the Borrow Area for Contracting Officer's approval.

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