Amendment 02 - RFI_01 20 00 Tech Spec3 Option.pdf

Saugerties Harbor New York Federal Navigation Project 2024

SECTION 01 20 00 Page 1

SECTION 01 20 00 TECHNICAL SPECIFICATIONS

03/24

TABLE OF CONTENTS

PARAGRAPH TITLE PAGE

1. Work Covered by Contract Price 2

2. Order of Work 3

3. Character of Materials 3

4. Site Conditions 4

5. Permits 4

6. Clamshell Bucket 4

7. Placement of Dredged Materials 4

8. Dredging 20

SECTION 01 20 00 Page 2

TECHNICAL SPECIFICATIONS

1. WORK COVERED BY CONTRACT PRICE: The work consists of furnishing all plant, labor, materials, and equipment, and performing all work in strict accordance with the specifications and drawings for the dredging of the Saugerties Harbor Federal Navigation Channel project at

Saugerties, New York; and placement of material from the dredging areas within the Federal Navigation Channel at the Government furnished placement site identified as U-3A, and located on Houghtaling

Island, Hudson River, New York. Removal and placement consist of dredging a total of approximately 33,406 cubic yards of material from the dredging area above the grade of twelve (12) feet below MLLW, including a vertically applied one (1) foot of allowable over depth, as shown on the contract drawings. All dredged material shall be transported to, offloaded, and placed in site U-3A, in the area designated on the contract drawings. Three hundred and sixty-five

(365) calendar days have been allowed for completion of the contract.

However, all in-water work occurring at Saugerties Harbor dredging area, Hudson River, NY, shall be completed no later than October 31,

1.1 Mobilization and Demobilization:

1.1.1 Mobilization shall include the costs for all activities required to initiate actual dredging operations, such as, transfer of dredge(s) and attendant plant and equipment to site, and/or other incidentals directly applicable to such transfer. Demobilization shall include general preparation and transfer of dredge(s), attendant plant, and equipment from the site to its home base, and cleanup of dredging and disposal areas. All costs connected with the mobilization and demobilization of all the Contractor’s dredging plant and other marine equipment shall be included in the Contractor’s “JOB” price for Contract

Line Item Number (CLIN) 0001, Mobilization and Demobilization. Sixty percent (60%) of the “JOB” price will be paid to the Contractor upon completion of their mobilization to the work site. The remaining forty percent (40%) will be paid to the Contractor upon completion of their demobilization work. The cost for work other than mobilization and demobilization of the Contractor’s dredging plant and marine equipment shall not be included in this item.

1.1.2 In the event the Contracting Officer considers that the amount in this item that represents mobilization (60%) does not bear a reasonable relation to the cost of the work in this contract, the

Contracting Officer may require the Contractor to justify this portion of the bid. Failure to justify such price to the satisfaction of the

Contracting Officer will result in the payment of actual mobilization costs, as determined by the Contracting Officer 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 is not subject to appeal.

1.1.3 Due to the existence of an active eagles nest within 660’ of the main trail road to Houghtaling Island, land access to the upland placement site may be prohibited. If land access is not available, SECTION 01 20 00 Page 3 mobilization and demobilization of heavy equipment via the Hudson River will be required until such time as use of the trail road allowed.

1.2 Dredging. The contract price per cubic yard for “Dredging” shall include all costs associated with removal of material from the dredging area, transport of the dredged material to the upland placement site, and offloading and placement of the dredged materials into the designated placement site containment areas (A or B) as specified herein and on the contract plans. Dredging does not include removal of ledge rock, large boulders, large rock fragments, wrecks, snags and piles which cannot be removed or buried below project depth without blasting. Should ledge rock or other material which cannot be removed without blasting be encountered, the Contractor shall remove all overlying material which in the judgment of the

Contracting Officer, and/or his representative can be removed and report the location. Nothing in this paragraph shall be construed as prohibiting the removal of excepted material by special means at prices agreed upon and approved in accordance with Contract Clause entitled: “DIFFERING SITE CONDITIONS” (FAR

52.236-2).

1.3 Placement Site Activities. The contract price for “JOB” for

“Placement Site Activities” shall include all costs associated with the design, construction, operation, and final stabilization of the U-3A upland placement site in accordance with the contract plans and specifications and the approved Dredged Material Placement and

Mitigation Plan.

1.4 Equipment fuel transport to Houghtaling Island via river. The contract price of “JOB” for “Equipment fuel transport to Houghtaling

Island via the Hudson River” shall include all costs associated with transporting equipment fuel to Houghtaling Island, via river. This work is conditional on the continued loss of land access to Houghtaling

Island, due to an active eagle nest near the trail access road. Once land access is restored, the Government will cease to pay for this work.

2. ORDER OF WORK AND START OF DREDGING WORK. In-water dredging work shall start no earlier than August 15, 2024 and shall be completed no later than October 31, 2024.

3. CHARACTER OF MATERIALS

3.1 Results of grain size analyses performed on composite samples collected in April 2019 from the area to be dredged are as follows:

GRAIN SIZE IN PERCENTAGE (%)

Dredging Area GRAVEL SAND SILT CLAY

Saugerties Harbor 1.0 53.0 33.0 13.0

This data is to be used as a preliminary reference only. See Section 00

90 01, Attachment J for detailed sediment physical and chemistry data

SECTION 01 20 00 Page 4 reports.

3.2 To review the complete report(s) of sediment analyses, all bidders should contact the U.S. Army Corps of Engineers New York District, Albany

Field Office, at 518-273-0870.

3.3 Material to be removed to gain the depths within the limits called for in these specifications and drawings is material that has shoaled in the dredging area since it was last dredged to authorized dimensions in the following year:

Dredging Area Last Maintenance Dredging

Saugerties Harbor 2015

4. SITE CONDITIONS. Bidders are expected to examine all work sites, including the dredging area and the dredge material placement area, and decide for themselves the conditions affecting their operations prior to submitting their bids. Records of previous dredging operations are available at the U.S. Army Corps of Engineers, New York District, Albany

Field Office, 1 Bond Street, Troy, NY 12180. See Contract Clause entitled:

“SITE INVESTIGATION AND CONDITIONS AFFECTING THE WORK” (FAR 52- 236-3).

5. 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).

6. CLAMSHELL BUCKET. As a mechanical dredge will used for the

Saugerties Harbor dredging area, the dredges clamshell bucket shall be a closed environmental bucket. The Contractor shall utilize best management practices to ensure that turbidity is minimized in the water.

7. PLACEMENT OF DREDGED MATERIAL

7.1 GENERAL. All material to be dredged, exclusive of all floatable material, shall be transported and deposited at the Government furnished placement site identified as Site U-3A, as described in paragraph 7.2 below, and as shown on the plans.

7.2. Government Furnished Placement Site. One Government furnished placement site, as shown on the plans, is available for use for the work associated with this contract. Site specific information, including special conditions for use of the site, is identified below. The

Contractor is advised to thoroughly inspect the furnished placement site prior to submission of his bid.

7.2.1. Site U-3A. Site U-3A is a previously used 78-acre upland Confined

Disposal Facility (CDF) located on the southern end of Houghtaling Island.

Approximately 30-acres of the site are available to the Contractor for the placement of dredged materials from this maintenance dredging project. CDF Areas A & B have been designated for the placement and containment of dredged materials as shown in Plan Sheet 3 of 9.

SECTION 01 20 00 Page 5

Dredged materials removed from the Saugerties Harbor dredging area will be placed in Area A. Material excavated from “Dredging Area B,” as indicated in Plan Sheet 7 & 8 of 9, will be placed first in Area B of the DMPS. The general interior site elevations in Area A a n d B range from approximately 35 feet to 50 feet NAVD88. There are existing usable containment dikes with approximate top elevations of 50 feet NAVD88 on the site. Additional earthwork will be required to repair and maintain existing dikes. Areas A & B utilize an existing pre-approved influent pipeline access corridor on the west side adjoining the Hudson River that may be used for pipeline access from the Contractor’s pump out/mooring facility to the interior of the placement site. Area A

& B also have existing pre-approved effluent pipeline outlet corridors, which are also located on the west side of the placement site adjoining the Hudson River. The Contractor is required to use these ingress and egress corridors for locating and installing their pipelines.

The Contractor is responsible for ensuring that dredging and placement operations comply with all environmental and water quality standards.

Contractors shall be required to monitor activities and be prepared to adjust their dredging and placement operations as necessary to ensure compliance.

7.2.2 Land Access. Limited land access is available along an

access trail from the northerly end of Upper Schodack Island.

The access trail is approximately 4 miles long, unpaved, rough, and unimproved, and is generally in very poor condition. Several segments of the access trail are adjacent to wetlands that shall not be disturbed. The north entrance and northerly segment of the access trail is on New York State Parks and Recreation owned lands within the

Schodack Island State Park, located off NY Route 9J. The access trail is designated as a multi-use recreation trail within the boundaries of the

State Park. The Contractor will secure permission for use of the New

York State owned segment of the access trail subject to the Contractor agreeing to special conditions imposed by New York State Office of

Parks, Recreation and Historical Preservation (PARKS). If the

Contractor elects to use the access trail across NYS lands, it shall only be used for limited transport of equipment (e.g., bulldozer, loader). The Contractor shall be responsible for performing all activities and for payment of all costs associated with meeting the NYS requirements and conditions of use. The Contractor shall coordinate all planned passages with NYS Parks designated representative prior to each use of the access trail. The Contractor will be required to submit a signed release from NYS Parks and Recreation at the completion of the contract indicating that all conditions of use for the access trail were met and any restoration necessitated by the Contractor’s use have been completed prior to issuance of final payment. [As of March 2024, NYS

DEC and NYS PARKS has determined the existence of an active eagle nest(s) within close proximity of the sole trail access road to the site, located on Schodack Island. Because of this, use of the trail will be severely limited, if not paused, during eagle nesting season

(January – September). Access to Houghtaling Island may require use of boats/barges via the Hudson River.]

7.3 Avoidance of Cultural Resources. The historic remains of three icehouse complex sites (Site A, Site B and Site C) are located on

Schodack- Houghtaling Island. Of the three sites, only Site A is in close proximity to the proposed placement operations. Site A is located on the exterior east side of Area B, adjacent to Schodack Creek, and

SECTION 01 20 00 Page 6 just south of Area B northeast corner. The Government has designated this area as an area of avoidance for the duration of the Contractor’s dredging and placement operations. The Contractor will restrict his activities to the area within the existing pipeline corridor. The

Contractor will be solely responsible for any damage inflicted upon this cultural resource caused by his activities. For additional site information, see Section 00 90 01, Attachment J.

7.4 Site Investigation and Pre-bid Site Visit. Before using the upland placement site for the deposit of the dredged material, the Contractor shall investigate the site’s characteristics, capacity to various elevations, and the suitability of available materials for use in the construction of containment structures and other work required by these plans and specifications. The Contractor shall adhere to all conditions for the use specified. A onetime pre-bid site visit sponsored by the

Government will be scheduled during the bidding period. The Government will issue specific information pertaining to the pre-bid site visit once this event has been scheduled.

7.5 Design, Construction and Operation. The delineation of the existing area, with the basic design and layout information of the dredged material placement site, shall be provided by the Government. The construction, operation and interim and final stabilization of the dredged material placement site are the responsibility of the

Contractor and subject to the approval of the Contracting Officer. The

Contractor shall operate the site to ensure that it functions to produce an effluent at the point of compliance that meets the minimum water quality standards as prescribed in the NYSDEC Water Quality

Certification. Containment dikes are required for the use of the placement site. The Contractor shall investigate the suitability of all existing dikes and/or dike construction materials proposed for use under this contract. The Contractor shall rebuild and stabilize any existing dikes as necessary in accordance with the plans and specifications, and as required to provide effective treatment and containment of the dredged material within the placement site.

7.6 Dredged Material Placement and Mitigation Plan. The Contractor shall submit for approval his Dredged Material Placement and Mitigation

Plan at a pre-construction meeting. The plan shall include:

a. Identification of the site to be utilized;

b. Acknowledgment of all special conditions (i.e., NYSDEC, etc.)

for site use;

c. Contractor’s proposal for equipment and personnel access to the site;

d. Clearing, grubbing and disposal plan if necessary;

e. Refueling plan for land-based equipment;

f. Locations and cross-sections of existing and proposed dikes;

g. Proposed location of mooring/pump out barge and depths to river bottom at proposed barge location;

h. Final maximum elevations and estimated quantities of placed dredged material on the site;

i. Excavation plan for borrow area(s) including: location, proposed cross-sections, and proposed quantity to be used for dike reconstruction and or repair;

j. Proposed method for transporting/conveying material from barge to the designated placement area including identification of type and

SECTION 01 20 00 Page 7 size of any pumps, pipelines, etc.;

k. Proposed manner in which the dredged material will be placed, distributed, and managed within the placement cells during placement operations;

l. Proposed manner in which the discharged influent, ponding depth and weirs will be managed to control effluent water quality at the point of compliance;

l. Interim and permanent turfing/revegetation plan;

m. Plan to stabilize and close site at end of contract, including completion and delivery of site as-built survey.

7.6.1 Dredged Material Placement and Mitigation Plan Approval.

Approval of the plan by the Contracting Officer is required prior to commencing with placement site preparation. The Contractor shall conduct his work in accordance with the approved Dredged Material

Placement and Mitigation Plan, however, approval of the plan for development of the placement site does not in any manner relieve the

Contractor of his responsibility for the adequacy of the construction and operation of the containment and drainage facilities required.

7.7 Pre-Construction Site Visit. Prior to actual construction of the placement site, the Contractor and the Contracting Officer and/or his representative shall visit the site for the purpose of delineating areas of avoidance (cultural and/or wetland concerns).

7.8 Site Preparation.

7.8.1 Clearing and Grubbing.

7.8.1.1 General. All woody vegetation shall be cleared from the total interior area of all containment cells, including the inside interior slopes of the existing containment dikes, as required for the preparation and maintenance of the placement site, and for the access needs of the

Contractor. All This work shall be completed as approved by the

Contracting Officer. No removal of trees/vegetation is permitted as follows: beyond the outside toe of the existing or proposed exterior dikes, with the exception of the pipeline ingress/egress corridors;

within the 100-foot minimum setback from the outside edge of the existing vegetation; and those trees marked as protected.

7.8.1.2 Clearing. Clearing shall consist of the removal and the satisfactory disposal of woody vegetation, including downed timber, snags, brush, and rubbish occurring within the areas to be cleared.

Vegetation in areas to be cleared, and where the excavation of borrow material will not be performed, shall be cut off flush with or below the original ground surface.

7.8.1.3 Grubbing. Grubbing consists of the removal and disposal of stumps, roots larger than 3 inches in diameter, and matted roots. The contractor shall grub all areas included within the actual footprint of the base and any constructed or modified/amended containment or spur dikes.

7.8.1.4 Grading. Grading consists of the creating a level base within the containment cells. Material within the cells shall be graded evenly to the lowest level allowed within each containment cell.

SECTION 01 20 00 Page 8

7.8.1.5 Disposal of Materials The Contractor shall dispose of all trees, stumps roots, brush, rotten wood, and other vegetative refuse from the clearing and grubbing operations. These materials may be hauled and disposed of inside the site in the designated tree and brush management area or removed from the site and disposed of at an approved location.

Limbs and branches shall be trimmed from the tree to reduce the number of voids when stacking. All materials disposed of in the designated areas shall be placed in an orderly and uniform direction to keep the stacking of materials as tight as possible. Any material removed from the placement site shall become the property of the Contractor, and shall be disposed of in compliance with Federal, State and Local regulations.

Clearing and grubbing shall be made a part of the Contractor’s Dredged

Material Placement and Mitigation Plan.

7.8.2 Contaminated Subsurface Soil Within Containment Area B. The existing subsurface soil/sediments within existing containment cells

B.1, B.2, and B.3 have elevated levels of PCBs. No stripping or removal of the surface material, except where necessary for site activities.

With the exception of the existing earthen material used to form the above floor structure of the interior dike between cells B.1, B.2, and

B.3 no soil/sediment material from this area shall be used in the construction or rehabilitation of containment dikes.

7.8.3 The Contractor shall use only the designated borrow area identified on the plans. Area A.1 is the primary source of materials for the construction, repair or restoration of containment dikes, etc., and for final stabilization. If all available material is removed from the designated borrow area; the Contractor may borrow additional material from other areas within U-3A which are acceptable for the intended application and are approved by the Contracting Officer. The

Contractor is advised that brush and small to large diameter trees have been buried in the existing fill, including the designated borrow area, during previous dredge material placement operations. The presence of brush and trees in the fill may make excavation of these materials difficult if encountered. The proposed use and storage of approved existing surface soil shall be included in the Contractor’s Dredged

Material Placement and Mitigation Plan.

7.9 Construction and Maintenance of Containment Structures.

7.9.1 General. The Contractor shall construct, rehabilitate, and maintain all containment dikes, weirs and drainage structures as are necessary for confining the dredged material and for controlling placement site effluent water quality until acceptance of all work under the contract.

7.9.2 Protection and Maintenance of Structures and Adjacent Areas.

The Contractor shall be responsible for the maintenance, repair and stability of all dikes, roads, and structures, used under the contract.

The Contractor shall restore all dikes, roads, and areas it disturbs through its operations, to a condition satisfactory to the Contracting

Officer, at no additional cost to the Government.

7.9.3 Inspection of Structures and Adjacent Areas. The Contractor shall inspect all dikes, roads, effluent weirs, and adjacent areas

SECTION 01 20 00 Page 9 utilized during his operations on a continual basis to assure their integrity, safety, and stability. The Contractor shall note any deficiencies observed during the inspection and the resulting corrective action(s) taken in his Daily Quality Control Report.

7.10 Dredged Material Placement Site Design and Operation Requirements.

7.10.1 Minimum Retention Time. The existing dredged material

placement site area is specified. However, the Contractor may be required to perform additional work to ensure the total design storage area for dredged material placement is constructed and operated to maintain a sufficient retention time to produce effluent which meets the requirements of the NYSDEC Water Quality Certification. Computations verifying that the site to be used has sufficient capacity to provide at a minimum a 1-hour retention period with provisions to adjust the retention period as required to meet the effluent water quality standards shall be included in the Contractor’s Dredged Material

Placement and Mitigation Plan.

7.10.2 Minimum Ponding Depth. The Contractor should maximize the ponding depth throughout the placement operation to maximize retention times and effective settling as required to meet effluent water quality standards. The minimum ponding depth over the design storage surface area(s) shall be 2 feet, except during the initial development and decanting of the pond(s).

7.10.3 Capacity of Containment Area. If a hydraulic dredge or unloader is used, the minimum volume or capacity of the containment area may be estimated by the Contractor based on the following formula for computing the containment volume required to maintain a 1-hour minimum retention time:

Vr = FeQT =

2.25QT

Where:

Vr = volume required to maintain 1-hr retention time;

Fe = factor to account for hydraulic inefficiency of containment area = 2.25;

Q = flow rate = assume flow rate of hydraulic dredge or unloader, if used; T = required retention time

The following table provides values of Vr for various dredge sizes and flow rates. These values are given to the Contractor as a guide FOR

INFORMATIONAL PURPOSES ONLY:

Retention Time

SECTION 01 20 00 Page 10

Dredge

Size (in)

Q (cfs)

(1 hr = 3600 secs)

Vr (CF)

VR(CY)

243000

16 20 3600 162000 6000

10 7 3600 56700 2100

7.10.4

Containment

Dikes.

7.10.4.1 Location. The center-line alignments of the exterior and interior containment dikes are generally located as shown and described on the plans.

7.10.4.2 Side Slopes. The Contractor shall construct the side slopes as described on the plans. The contractor shall monitor all dike slopes to ensure that the stability of the containment dikes throughout the dredging and placement operations is maintained.

7.10.4.3 Height. The Contractor shall determine whether the height of the existing containment dikes is sufficient to maintain the minimum retention time required to meet effluent water quality standards, plus two feet of freeboard, during dredged material placement operations.

A minimum of one foot of freeboard shall be maintained following completion of all dredged material placement operations. Freeboard shall be understood to mean the measurement from the top surface of the retained materials, including water, to the top of the adjacent containment dike. Finished height elevations shall not include overbuilding allowances where settlement is anticipated. The maximum height for all dikes are elevation 50.0 feet NAVD88.

7.10.4.4 Top Dimensions. Containment and spur dikes shall be

constructed with grade stakes placed at no greater than 200-foot intervals to obtain a reasonably uniform top elevation. During use of the placement site, all containment dikes shall be maintained so as to have a minimum top width of fifteen (15) feet and a minimum freeboard of two (2) feet at all locations.

7.10.4.5 Containment Dike Material and Construction. The preapproved material that can be used to construct, raise, or reinforce existing containment dikes; shall be taken from the designated area identified as Area A.1 in site U-3A, except where otherwise specified or directed by the Contracting Officer. Suitable material from the designated borrow area is preapproved for use in dike construction. The borrowing of material from outside site U-3A shall not be permitted. Borrow material and the surface upon which it is to be placed shall be free of all debris, woody material, and accumulations of vegetation. Dike material shall be placed in approximately equal layers not exceeding twelve (12) inches in loose thickness and shall be compacted by the controlled traffic of spreading, hauling, or shaping equipment over each layer. Equipment shall be operated

SECTION 01 20 00 Page 11 on the fill in a manner that covers as much of the fill surface as possible during traffic compaction.

7.10.4.6 Use of Existing Dikes. The Contractor may use the existing containment dikes providing that: the interior slope and ground surface ten (10) feet out from the interior toe of the dike is cleared of vegetation; all holes, burrows and voids are repaired; and the Contractor inspects and confirms that the existing dike is stable, functional, and nonporous prior to the start of dredge material placement. Any existing dike as built, that does not conform to the dimensions specified on the plans, shall be improved by the Contractor, and constructed to the specified dimensions prior to use. The Contractor shall take all necessary actions during placement operations to prevent seepage through, and/or erosion of, the containment dikes.

7.10.4.7 Prohibited Construction Practices. The hydraulic placing of perimeter containment dikes shall not be permitted. The dredge pipeline shall not be permitted to enter the placement site through a perimeter or exterior dike.

7.11 Weir Boxes and Spillways.

7.11.1 General. During placement operations, drainage of the

containment area(s) shall be only through the existing government furnished weirs as detailed in the plans and specifications. The

Contractor shall maintain and operate the weirs at the locations shown on the plans.

7.11.2 Inspection of Weirs. The Contractor shall inspect all

government furnished weirs and outlet pipes to determine that they are sound, safe, without defect and capable of being operated as designed.

The Contractor shall be responsible for any repairs or maintenance required to ensure that they function as needed throughout the

Contractor’s placement site operations.

7.11.3 Weir Boards. There are existing weir boards provided with each weir. The Contractor shall inspect the boards to determine if they are sound, structural lumber and free of any damage or defect which would impair its usefulness or durability. The Contractor shall be responsible for replacing any boards that are unfit for service in the weir. Boards added to raise the elevation of the weir shall fit tightly on the lower boards and in the supporting framework. Boards shall be securely fastened in place so that they cannot be removed by unauthorized personnel. Boards shall be stored at the weir site in ready condition for regulation of the weir and pond height, and for immediate implementation of necessary corrective measures (e.g., cease overflow).

7.11.4 Weir Box Gangways. The Contractor shall inspect the Government furnished gangways to determine if they are sound, safe, and ready to be installed and used. The Contractor shall ensure that all weirs have gangways to enable personnel access for regulating the pond depth, elevation, and flow of water; for collecting samples of the mixture going over the weir, and for inspection and maintenance of the weir box. Increasing the width of the top and weir side of the interior containment dike may be necessary to install the weir box gangway.

SECTION 01 20 00 Page 12

7.11.5 Interior Weirs. The interior drainage system shall be operated by the Contractor to enable and control flow through the weir and pipeline, which can be completely stopped should a problem upstream or downstream of the weir box occur.

7.11.6 Exterior Weir. The effluent spillway system shall be operated by the Contractor to enable and control flow through the effluent pipeline which can be completely stopped should a problem meeting effluent water quality standards develop that cannot be resolved using other corrective actions. The treated effluent water shall be discharged to the receiving waters in the Hudson River by pipeline.

Effluent shall not be allowed to enter existing wetlands outside the diked areas nor shall any of these areas be disturbed.

7.11.7 Effluent Spillway Discharge Pipeline. The spillway discharge pipeline shall extend into the receiving waterway (minimum of ten (10) feet from the shoreline at low water) and shall have a diffuser at the end of the pipeline that is approved by the Contracting Officer. The discharge outlet opening shall be entirely submerged a minimum of one

(1) foot below the water’s surface at all times. Any pipeline extending into the waterway shall be adequately marked so as not to constitute a hazard to navigation.

7.11.8 Diffusers. The Contractor shall provide and install a diffuser on the end of all outlet pipes to dissipate the force of the water being discharged through a weir into another containment cell or returning to the receiving waterway. Diffusers shall be used to prevent the scouring of the materials below and adjacent to the discharge outlet.

7.11.9 Geomembrane Splash Pads. The Contractor shall inspect, reinstall or repair as necessary, and maintain the geomembrane splash pad on the dike slopes and under the discharge end of all interior outlet pipes to ensure that they will continually function to reduce scouring during the discharge of slurry from the dredge or pump out facility into the disposal site, and/or influent from the weir(s). All elements of the geomembrane splash pad shall be in accordance with these plans and specifications. Installation of the geomembrane shall be in accordance with the manufacturer’s guidelines.

7.12 Interim Turfing.

7.12.1 General. Interim turfing of the exterior slopes of all newly constructed or rebuilt containment dikes, ingress and egress corridors, areas disturbed by the Contractor’s operations outside the dikes, and any other areas of disturbances identified by the Contracting Officer, shall be performed immediately after completion of the construction of the placement site and containment structures.

7.12.2 Materials. See Para. 7.19.3.

7.12.3 Interim Turfing Plan. The Contractor’s plan for interim turfing is subject to approval by the Contracting Officer and shall be included in his Dredged Material Placement and Mitigation Plan.

SECTION 01 20 00 Page 13

7.13 Protection of Areas Adjacent to Containment Structures.

General. The Contractor shall take all precautions which in the opinion of the Contracting Officer may be necessary to prevent the escape of material through pipelines, weirs, embankments, and bulkheads, or otherwise into navigable waters or into adjacent upland and wetland areas.

7.13.1 Mechanical Equipment. No mechanical equipment shall be allowed in any wetland area unless specific approval is given by the Contracting

Officer.

7.13.2 Drainage. Development of the placement site shall be done so as to prevent obstruction of drainage on upland areas adjacent thereto, and to leave free, clear and unobstructed outfalls of sewers, drainage ditches, and other structures affected by the placement operations.

7.13.3 Containment Area Structure Restoration. The Contractor shall restore any feature of a containment area structure as required to prevent the escape of dredged material from the placement site on to adjacent areas.

7.13.4 Physical Features Outside of Containment Structures. The

Contractor shall be solely responsible for all dikes, roads, pavements, curbs, signs, lawns, bulkheads or any other properties or areas they disturbs during their performance of the work under this contract. The

Contractor shall be required to repair any such damage at his own expense and to the satisfaction of the Contracting Officer.

7.13.5 Inspection. Prior to the commencement of operations and after the completion thereof, a joint inspection by representatives of the

Contractor, the Contracting Officer and local interests pertaining to the above will be made.

7.14 Costs for Construction and Maintenance of Containment Structures.

All embankments or bulkheads with necessary weir(s), required for confinement and control of the dredged materials to meet WQC effluent discharge requirements, shall be constructed and/or maintained by the

Contractor, and the cost thereof included in the applicable contract price.

7.15 Contractors Placement Site Operations.

7.15.1 General. All dredged material shall be deposited as evenly as possible by normal hydraulic or mechanical filling operations. The

Contractor shall establish and maintain measures to prevent re-suspension of previously placed contaminated sediments in containment areas A and B during filling operations. The Contractor shall submit his plan of operations to the Contracting Officer and commence operations subject to Contracting Officer approval.

7.15.2 Order of Work. All dredge material areas that contain low levels of PCB contaminants per NYSDEC Class B sediment quality thresholds, shall be removed and placed first.

SECTION 01 20 00 Page 14

7.15.3 Surface Topography. Depressions in which pools of water will collect and stagnate shall not be formed either during or after placement operations. Mounds constructed during placement operations shall not be formed higher than the freeboard elevation of the confining dikes.

Sloping topography shall direct flows towards outlet structures and away from areas of the site where water will become trapped. All areas shall be graded as required, and in the opinion of the Contracting

Officer, left as level and sightly as possible at the end of placement site operations.

7.15.4 Drainage Structures and Features. The Contractor shall be required to construct solely at his expense, such other drainage structures and features as may be directed by the Contracting Officer to provide suitable drainage of the placement site and any adjacent area where the drainage is affected by operations in the placement site.

7.15.5 Work Stoppage. In the event of a temporary stoppage of work due to seasonal conditions, the elevation of the weir shall be maintained so as not to allow the pooled water to become stagnant.

7.15.6 Freeboard. During dredged material placement operations, a freeboard of two (2) feet or more, measured vertically between the surface of the retained materials, including water, and the top of the adjacent confining dikes, shall be maintained at all times. If the required freeboard is not met, the Contractor shall stop the pumping/placement of the dredged materials into the placement site until corrective action has been taken which is satisfactory to the Contracting Officer. Upon completion of placement and final stabilization operations, a minimum freeboard of at least one (1) foot shall be provided at all locations prior to final contract close out.

7.15.7 Cold Weather Operation. During cold weather periods, no pumping/placement of dredged materials into the placement site will be permitted when the ponded area around the weir box and outlet pipelines is frozen. Open water shall exist in the ponded area of the containment cells at all times that the disposal operations are in progress to allow mixing of the effluent in the pond, and to prevent water and materials from short-circuiting the containment process by flowing over any solid ice surfaces towards the weir.

7.15.8 Inspection. The Contractor shall inspect the operation of the placement site on a continual basis. The inspection shall include but not be limited to structures, equipment, safety, security, freeboard, drainage, and seepage. While the scows are unloading during pump out operations, the Contractor shall place a watchman at the discharge end of the pipeline and at the exterior weir if a pond has formed around the weir to monitor the placement, flow and function of the site. If there is no pond formed at the weir, then a watchman shall inspect the site along the flow path of the discharged slurry. At the end of pump out operations, the Contractor shall ensure that a complete inspection of the placement site is performed.

SECTION 01 20 00 Page 15

7.15.9 Illumination of Placement and Monitoring Operations. The areas where placement (at the discharge point, etc.) and monitoring operations are in progress shall be illuminated during the hours of darkness. While work is in progress, all work areas shall be lighted by at least the minimum intensities specified in EM 385-1-1, Table 7-

1.

7.15.10 Radio Communications. Monitoring of the discharge operation by radio communication from the discharge location to the lever, drag tender or crane operator during all placement operations is required.

7.15.11 Reporting Requirements. The Contractor shall maintain a daily record of all placement site operations. This requirement shall be made as part of the Contractor’s Quality Control Plan, and each record shall be included in the Contractor’s Daily Quality Control Report.

Further instructions on the preparation and submittal of the reports will be furnished at the Preconstruction Conference.

7.16 Control of Dredged Material Placement Site Effluent.

7.16.1 General. The Contractor shall establish best management practices; and monitor and control placement site conditions and effluent water quality in order to comply with all standards prescribed in these specifications. The Contractor’s Quality Control Plan shall identify the best management practices, monitoring requirements and corrective measures which will be taken to control placement site conditions to ensure that effluent water quality meets the requirements identified in the New York State Water Quality Certification.

7.16.2 New York State Water Quality Certification (WQC). The

Contractor shall comply with all requirements identified in the New York

State Water Quality Certificate including all Natural Resource Permit

Conditions. A copy of the WQC is included in Section 00 90 02.

7.16.3 Weir Height. Weir height shall be reviewed by the Contractor on a continual basis to ensure that all effluent water quality requirements are met. The Contractor shall perform corrective action(s) (raise the elevation of the weir crest, stop pumping into the placement site to allow suspended material to settle out, etc.) whenever the turbidity of the effluent at the point of compliance approaches the maximum limit specified in the WQC. All corrective actions, including changes in the weir elevations, shall be reported by the Contractor in the Daily Quality Control Report.

7.17 Testing.

7.17.1 General. The Contractor shall be responsible for performing sampling, testing, and reporting for all required samples and tests at all points of compliance, as prescribed by this specification. The

Contractor shall submit the calibration dates for all applicable testing equipment.

7.17.2 Sample Collection. The sample collection methods described herein shall be followed as applicable to each of the specified point of compliance locations. Grab samples collected at the weir shall be made up by partially filling, without overflow, a one (1) quart

SECTION 01 20 00 Page 16 container of the material flowing over the weir at not less than ten different places along the length of the weir and combining the mixture in a clean bucket or other suitable container. Grab samples of the mixture taken from the river shall be obtained in a clean, appropriate sample container at the locations and depths identified in the New York

State Water Quality Certification (Section 00 90 02). Samples for effluent monitoring shall be collected while the dredge is discharging into the placement site whenever practicable. The Contractor shall record the time that the sample was collected/tested, the depth of flow over the weir and the status of the dredge at time sample was collected.

7.17.3 Effluent Testing.

7.17.3.1 Turbidity. Samples collected at the weir shall be tested for turbidity in accordance with the WQC (see Section 00 90 02).

Turbidity testing shall be required during overflow and following any reduction in weir height (e.g., removal of weir boards). The Contractor shall record the time when the weir height was reduced and the time the effluent overflow was sampled/tested. Test results and times for all samples taken shall be reported in the Contractor’s Daily Quality

Control Report.

7.17.3.2 Settleable Solids. Samples at the weir shall be collected and tested for settleable solids in accordance with the WQC (see Section

00 90 02). Test results and times shall be reported in the Contractor’s

Daily Quality Control Report.

7.17.3.3 PCBs. Samples at the weir shall be collected and tested for

PCBs in accordance with the WQC (see Section 00 90 02). Test results and times shall be reported in the Contractor’s Daily Quality Control

Report.

7.17.3.4 Other Tests. Other tests for effluent monitoring shall be performed and reported at the frequencies prescribed by these specifications.

7.17.4 Chemical Clarification of Effluent. A polymer flocculent may be used as a corrective measure whenever the effluent turbidity approaches the WQC daily maximum value(s). The Contractor’s proposed polymer, including Manufacturer’s specifications, MSDS and recommended dosing, shall be submitted for approval as part of his Dredged Material

Placement and Mitigation Plan prior to commencement of placement operations. The Contractor shall use the polymer in accordance with the Manufacturer’s recommendations to effectively control the effluent.

The approved chemical clarifier shall be stored on the placement site, and be ready for use, should corrective measures be required.

7.17.5 Visual Quality. The Contractor shall note and record in the

Daily Quality Control report the visual quality of the effluent (clear, slightly turbid, very turbid) overflowing at the weir.

7.17.6 Laboratory Services. Sample analysis shall be undertaken at an approved laboratory meeting New York State Health Department standards.

SECTION 01 20 00 Page 17

7.17.7 Reporting Requirements. Records of all water quality test results shall be submitted to the Contracting Officer and to the NYS

Department of Environmental Conservation, in accordance with these specifications. Any corrective measures, if needed, shall also be submitted to each of the above, and included on the Contractor’s Daily

Quality Control Report.

7.18 Final Clean-up and Stabilization.

7.18.1 General. The Contractor shall be solely responsible for all work required for the interim stabilization, final clean-up and stabilization of the placement site, and other associated features utilized for this contract.

7.18.2 Drainage of Surface Water and Dewatering of Dredged Materials.

Following the completion of dredging operations, the ponded water behind the effluent discharge weir shall be drained to the lowest surface elevation allowed by the fixed weir box and adjacent fill area.

Discharge through the effluent weir during the decanting process shall be controlled so as not to contravene the effluent water quality standards. The Contractor shall continue water quality testing of the effluent as prescribed regardless of the flow, until drainage of the ponded water behind the weir is complete. Ponded water behind the interior weirs shall be drained to the lowest surface elevation allowed by the fixed weir in order to permit surface water to flow towards the effluent weir for discharge from the site.

7.18.3 Felled and Exposed Trees. NOT USED.

7.18.4 Removal of Contractor Equipment, Plant and Materials. With the exception of the weirs, weir boards, gangways, and outlet pipelines;

the Contractor shall remove all equipment, plant and materials installed by the Contractor for use in his placement operations. These items shall be completely removed from the site; and the Contractor shall repair and stabilize all areas affected by their removal, as approved by the Contracting Officer. Any equipment, plant, or material that the Contractor proposes to leave in place, if approved by the

Contracting Officer, shall be fully secured from access, non-hazardous to normal usage, and shall not allow the escape of placed material or be in any way a detriment to the stability and integrity of other structures in the surrounding area.

7.18.5 Securing and Stabilizing Weirs and Outlet Pipelines. The

Contractor shall secure all weir, gangways, and outlet pipeline openings, as approved by the Contracting Officer, to prevent casual access and theft by intruders. Stop logs shall be stacked neatly in a location near the weir they were used in.

7.19 Permanent Turf.

7.19.1 General. Upon completion of all other operations in the placement site, including the placement and acceptance of the protective cover, the Contractor shall establish permanent turf for the stabilization and restoration areas affected by his operation as identified in these plans and specifications. The Contractor’s permanent turf plan is subject to approval by the Contracting Officer

SECTION 01 20 00 Page 18 and shall be included in his Dredged Material Placement and Mitigation

Plan.

7.19.2 Turf Areas. The Contractor shall establish a permanent turf on the following areas: the top, exterior and interior slopes of the retaining dikes; the fill area from the interior toe of the dike to ten

(10) feet out from the toe; ingress and egress corridors (except included areas delineated as wetlands); and all other areas on or outside the dike disturbed by the Contractor’s operations.

7.19.3 Materials. The Contractor shall furnish all materials, plant, labor, and equipment required for the establishment of interim and permanent turf. The following seed mixes are recommended for both interim and permanent turf:

Fall seed mix: Azure Sheeps Fescue @ 10#/Ac

Reliant Hard Fescue @ 10#/Ac

Western Wheatgrass @ 10#/AC

Blue Stem @ 10#/Ac

Canada Blue Grass @ 10#/AC

Spring seed mix: Azure Sheeps Fescue @ 10#/Ac

Reliant Hard Fescue @

10#/Ac Switchgrass @

10#/Ac

Blue Stem @ 10#/Ac

Canada Blue Grass @ 10#/Ac

The Contractor may submit alternative seed mixes for approval. The proposed turf plant species shall be types that are compatible to the

Hudson Valley climate and that will thrive in the conditions found at the site.

The following soil amendment is recommended: 10x10x10 fertilizer @

600#/Ac.

7.19.4 Installation. The installation of turf materials shall be accomplished by whatever means the Contractor elects subject to approval by the Contracting Officer. All surfaces that have been damaged by the

Contractor’s operations and/or by erosion, that in the opinion of the

Contracting Officer require restoration, shall be repaired by the

Contractor prior to seeding.

7.19.4.1 Seeding Period. Permanent seedings shall be made during the period between May 1st and August 15th. Temporary fall seeding shall be made during the period between August 16th and September 30th.

Temporary seeding is not recommended between October 1st and April 30th.

The Contractor shall immediately stabilize all areas requiring turf that have not been seeded, at such time seeding is prohibited. This interim stabilization shall be approved by the Contracting Officer.

7.19.4.2 Interim Stabilization. The Contractor shall stabilize all areas that have not established a satisfactory stand of turf within thirty (30) days of the end of current seeding period and in those areas that he plans to seed at the start of the following seeding period. Such interim

SECTION 01 20 00 Page 19 stabilization plan is subject to approval by the Contracting

Officer and shall be included in the Contractor’s Dredged Material

Placement and Mitigation Plan.

7.19.5 Inspection and Acceptance of Turfed Areas. The Contracting

Officer will inspect the turfed areas thirty (30) days after seeding is completed to ensure that there is a satisfactory stand of turf to prevent erosion of the underlying soil. A satisfactory stand of turf is defined as turf which is free from disease and injurious insects, with a minimum of one-hundred (100) grass plants per square feet.