DREDGING
The contract price per cubic yard for dredging shall include the cost for removal and disposal of all materials as specified herein or indicated on the drawings.
2. ESTIMATED QUANTITIES. The estimated quantities shown in the bidding schedule for dredging includes material to be removed to the maximum limit of overdepth dredging as follows:
Standard Dredging. The total estimated quantities of material to be removed in the required dredging prism (exclusive of overdepth), as shown in the bidding schedule for Items 0002 - 0010, 0012 and 0013 are as follows:
Bid Item Cubic Yards BASIC SCHEDULE 0002 406,000 0003 1,977,000 0004 305,000 0005 90,000 0006 789,000 0007 4,000 0008 36,000 0009 6,000 OPTION SCHEDULE 1 0010 1,151,000 OPTION SCHEDULE 2 0012 0 0013 29,000 These quantities will be used in determining adjustments, if any, under the terms of Special Clause "VARIATIONS IN ESTIMATED QUANTITIES - DREDGING".
2.2 Overdepth Dredaina. Overdepth dredging consists of both required and allowable overdepth as specified in paragraph "OVERDEPTH AND EXCESSIVE DREDGING". The estimated amount of overdepth dredging for Items 0002 - 0010, 0012 and 0013 are as follows:
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3. SITE CONDITIONS. The material deposited after the previous dredging consists of soft to very soft silty clay and loose sands. Virgin material below previous dredging consists of stiff to very stiff clays and dense sands, except that in the outer reaches virgin material consists of soft, silty clays and loose sands. In accordance with Contract Clause "SITE INVESTIGATION AND CONDITIONS AFFECTING THE WORK (FAR 52.236-003)", the Contractor is expected to examine the site of the work.
4. DREDGING. 4.1 General. Attention is directed to Paragraph "ORDER OF WORK" Section "SUPPLEMENTARY CONDITIONS", wherein time restrictions for certain items of work are specified. Unless otherwise authorized, all dredging shall be performed in the presence of the Contracting Officer. The dredging areas are divided into polygons which are designated for specific disposal sites as indicated on the drawings.
4.2 Dredging Plan of Operation. Prior to any dredging work, the Contractor shall submit a dredging plan for review and comment. Dredging shall not commence until all comments have been answered to the satisfaction of the Contracting Officer. The plan shall show order of dredging,
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4.3.1 Inner Harbor Turning Basin Wings. Polygons: Schnitzer and Todd as shown on the drawings.
4.3.2 Inner Harbor Channel. Polygons: IC-10, 11, 12, 29, 30, as shown on the drawings.
4.4 Debris Grid. Material dredged by the clamshell method to be disposed at the ocean disposal area shall be loaded on barges and scows at the dredge site by passing the material through a grid with openings of not more than 12 inches in any dimension. If it is evident that the material is free of debris the Contractor may request in writing to the Contracting Officer that the grid be removed. Collected debris shall be disposed of as specified in Paragraph "DISPOSAL OF DEBRIS".
4.5 Overflow and Leakage. 4.51 Barges and Scows. No overflow of dredged material or water will be allowed from the receiving barges or dump scows during dredging operations, except as follows: Overflow will be allowed under the following conditions: (1) the material is dredged with a hydraulic dredge (cutterhead, suction, or vortex type); (2) only dense, clean sands are dredged, as approved by the Contracting Officer; and (3) the material is to be disposed of in the ocean disposal area or the Sonoma Baylands disposal area. Where overflow is allowed, overflow time shall be limited to 15 minutes and the discharge shall be below the water surface.
4.5.2 Overflow from Hopper Dredges. Overflow will be allowed, except for material to be disposed of at the Galbraith disposal area. During hopper dredging, the time of overflow of water and dredged material from hopper bins shall
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4.5.3 Spillage and Leakage. During transport to the disposal sites, water and dredged material shall not be permitted to overflow, spill, or leak out of barges, hopper bins or dump scows. For material to be disposed of at the Galbraith disposal area, the Contractor may be required to take special precautions such as lining the barge or bin if there is any evidence of leakage of material.
4.5.4 Monitorinq of overflow time and leakaae shall be as specified in Section "QUALITY CONTROL". The Contractor shall record draft of hull for each scow load as specified under quality control.
4.6 Survey of Barge Filling Area. In the event the Contractor chooses to fill a receiving barge or dump scow, the receiving vessel shall be located in an approved anchor site. The Contractor shall be required to perform both a predredge and a post survey of the anchor site by means of an independent surveyor and the Contractor shall be required to remove any shoals attributed to his operation at no additional cost to the Government. Surveys shall be in compliance with Section "HYDROGRAPHIC SURVEYS".
4.7 Horizontal Position Monitorinq of Dredge. A short to medium range Electronic Positioning System (EPS) shall be activated during dredging operations. This EPS shall be established, operated and maintained by the Contractor during the period of the contract when dredging work is actively underway. The EPS using range-range methods shall display and record the vessel's location continuously during dredging operations, and for open water disposal operations as specified in Paragraph "Disposal Vessel Location (for Ocean Disposal Area)". A continuous graphic print-out plotter and/or graphic monitor shall be on any dredge utilizing a range-range positioning system and a complete copy record of the position data (dredge track history) including date, time, Lambert coordinates (Zone III) and Root Mean Square (quality of position closure), and such record shall be submitted to the Contracting Officer as part of the daily Quality Control Report. The Contracting Officer shall have access to the monitoring equipment in order to observe its operation during the dredging work. Hydraulic cutterhead dredges shall use a gyro-compass or other approved equipment to determine cutterhead location. Magnetic compass will not be acceptable. Laser alignment procedures utilized with range-azimuth instrumentation is acceptable for hydraulic cutterhead or clamshell dredge positioning. The Contractor shall provide all laser instrument locations as well as
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4.7.1 EPS System Confiquration. The EPS system shall be similar or equal in design, performance, accuracy, operating characteristics, and frequency to those identified in the following technical reference, which is available for purchase at the listed source, or which may be reviewed at the Construction-Operations Division, San Francisco District Office, 211 Main Street, San Francisco, California.
"Hydrographic Surveying" Department of the Army, Engineering Manual No. 1110-2-1003, 28 February 1991 USACE Publications Depot 2803 52nd Avenue Hyattsville, MD 20781-1102 4.7.2 EPS Shore-Based Control. The Contractor shall be responsible for establishing the horizontal control to locate active and/or passive shore-based EPS transmitter/ receiver devices. All control shall meet Third Order, Class I, accuracy standards as defined (and referenced) under chapter 2 of the Army Corps of Engineers manual "Hydrographic Surveying". The Contractor shall obtain all right-of-entry permits and/or leases as required to operate and maintain shore-based electronic equipment on public/private property no additional cost to the Government. at
4.7.3 EPS Calibration. EPS calibration techniques shall conform to standard hydrographic surveying practice consistent with minimization of systematic errors inherent to and consistent with the selected EPS system as specified under Chapter 6 of the Army Corps of Engineers manual "Hydrographic Surveying". The Contractor shall be responsible and reliable EPS calibration for the duration of ~ contract, and shall document calibration records as part of the daily Quality Control Report.
4.7.4 Ranqe-azimuth EPS calibration techniaues shall be calibrated strictly in accordance with the standard independent techniques identified in the Army Corps of Engineers manual "Hydrographic Surveying".
4.7.5 Range-range EPS calibration techniques shall be subject to the Contracting Officer's approval to ensure consistency with standard offshore hydrographic surveying procedures. Any degradation in positional accuracy during the course of this contract shall result in suspension of dredging operations, at no additional cost in time or money to the Government until the EPS control is returned to its normal operating levels. Monitoring the Root Mean Square (RMS of the lines-of-position (LOP's) will determine when calibration may
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4.7.6 EPS Breakdown. For range-range systems, the Contractor shall have a backup of at least one additional shore control transponder device which can be used as a fourth shore station. In the event that the hydrographic survey vessel is not utilized to provide the same type of electronic backup capability for the positional monitoring system, then the Contractor shafl have on hand at least one additional line printer and/or plotter, offshore guidance control, power supply, and spare parts kit for the receiver, etc., in the event of primary equipment failure. In the event that both the primary and backup systems are rendered inoperative, the Contractor shall make provisions within 36 hours to be operational. Dredging shall not be allowed during downtime period and no additional cost in time or money to the Government will be allowed. In the event of a failure in either the shore-based or ship-based electronic equipment, the Contracting Officer shall be immediately notified of the time of failure and time of repair. For all other EPS systems, the Contractor shall provide a written plan of action to include redundancy in system equipment and work methods to be used to maintain integrity of the dredging work.
4.8 Tidal Control Durina Dredainq. To establish dredging depth to the MLLW datum, the Contractor shall install two automatic recording tide gages with water level sensor near two different Corps of Engineers survey tide gage locations to compute average tidal changes. The tide gages shall provide continuous recordings of tidal changes for every 15-minute interval or each 0.1 foot change, whichever occurs first. Tidal changes shall be recorded in MLLW datum, with these changes visually provided to the dredge operator at all times during the dredging process to allow proper adjustment of dredge depth. A printed record of the tidal changes shall become part of the Contractor's daily auality control report.
4.9 Inherent Delays. The Contractor shall anticipate inherent delays while dredging around obstructions such as cable, pieces of metal, chains, etc., that may foul the cutterhead or clamshell and require removal. The bid prices shall include allowances for such inherent delays.
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Berth Dredging. For each berth, the first dredging pass shall be from the face of the wharf (edge of fender pile), for the entire length of the area to be dredged and shall be to at least the required project depth.
4.11.1 Maintaining Berth Operations. The berths to be dredged are active cargo terminal berths. Terminal operations must continue uninterrupted during the time of this contract. The Contractor shall closely coordinate his work with the Terminal Operators in conjunction with the Contracting Officer. Dredging work shall be scheduled during windows in the shipping schedule so as to avoid any interference with terminal operations or marine traffic. Shipping schedules will be variable and subject to change.
4.11.2 Cooperation with Other Contractors. There may be other Contractors performing construction work at the berths. The Contractor shall coordinate his work with the other contractors in conjunction with the Contracting Officer to avoid conflicts.
4.11.3 Access. Land side access will be available to Berths 32, 33, 38, 60, 61, 62, and 63 through guard controlled gates. The gates will be open from 8:00 a.m. to 5:00 p.m., Monday through Friday, except holidays. If the Contractor wishes to have access to the site at other times, the Contractor shall make prior arrangements with the Terminal Operator through the Contracting Officer for a guard to be present. Guards furnished at other than normal times shall be paid for by the Contractor. In the event that there is a labor dispute and picketing at the gates causes disruption or delay or extra cost to the Contractor, the Government will allow an appropriate extension of contract time but will not pay for any cost associated with such delay. All vehicles, equipment and personnel may be subject to search by the Terminal Operator or U.S. Customs of f icials upon entering or leaving the secured area.
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4.11.5 Storage. No equipment or materials shall be stored or stockpiled, nor any vehicles parked, except in areas designated by the Contracting Officer. No equipment shall be left in an elevated position when not in use. Storage space within the terminals is limited. Storage area, if required, will be assigned by the Contracting Officer. Exclusive or permanent use of assigned storage area is not guaranteed and Contractor may be required to move stored equipment and materials at his own expense.
4.11.6 Cooperation with Others. The Contractor shall schedule and perform his work in such a manner as to cause the least amount of conflict for the terminal operators and the public and to facilitate the smooth flow of traffic on local streets, in adjacent waters and within the terminals. The Contractor shall also cooperate with all others performing work on or near the site, including utility companies.
4.11.7 Information. Sounding records of the berths are available for inspection at the Engineering Service Counter, second floor of the Port of Oakland Building, 530 Water Street, Oakland. Information made available with respect to conditions at the site is not intended as a guarantee, either expressed or implied, but is furnished for general information only. It is expressly understood that neither the Government nor the Port assumes responsibility as to the sufficiency or accuracy of such information or of the interpretation thereof, or for any deduction or conclusion drawn therefrom by the Contractor. The information is made available in order that the Contractor may have ready access to the same information as is available to the Government and the Port and is not a part of this contract. No information derived from such inspection of records or from the Port Engineer or from his assistants or from the maps, plans or specifications relative to site conditions will relieve the Contractor from properly fulfilling all the terms of this contract. The Government retains the right to review the Contractor's productivity charts and logs.
5. OCEAN DISPOSAL. 5.1 General. Dredged material shall be transported by hopper dredge or barge and deposited by open water dumping at the Government-furnished ocean disposal area indicated on the drawings. Each load drop shall be identified by "X" and "Y" coordinates on the daily Quality Control Report for that day. Disposal operations shall be performed as directed and unless otherwise authorized (by verbal
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5.2 Site Manaqement and Monitorinq Plan {SMMP) Reauirements for Ocean Disposal Area. The Contractor shall adhere to the following SMMP provisions for disposal of dredge material at the ocean disposal area:
5.2.1 Barges shall not leave the bay when wave heights along the transit route are predicted to exceed 10 feet and wave periods are less than 12 seconds, or when waves are greater than 16 feet regardless of wave period. Under less severe weather conditions, extra precautions (such as reducing the load up to 15 percent) shall be taken to prevent spillage or other loss of material during transit to the site.
5.2.2 No disposal barge shall be filled above its load limitation defined as 80% of its load line, and all loads shall be certified by the Contracting Officer that the requirement has been met prior to departing for the disposal area.
5.2.3 For each tug boat captain's initial 12 trips to the ocean disposal site, barges shall be loaded to 80 percent of its load line. After each captain has completed the initial 12 trips to the satifaction of the Contracting Officer, subsequent barge loads may be filled to the load limitation, as permitted by sea conditions.
5.2.4 No water or dredged material shall be permitted to leak or spill from barges during transit to the ocean disposal area.
5.2.5 The maximum tow speed shall be 6 knots for loaded barges.
5.2.6 Tug boats with barges shall remain outside of the territorial sea boundary surrounding the Farallon Islands by following the inner portion of the outbound western shipping lane for transit into and out of the bay. Vessels shall remain at least 3 nautical miles from the Farallon Islands at all times. The Contractor shall furnish a vessel transit alignment plan for approval.
5.2.7 When barges are west of the Vessel Separation Scheme (VSS), the tug shall proceed directly to the ocean disposal site. The barges must be towed in transit routes that pass at least 3 nautical miles from the Farallon Islands.
5.2.8 The U.S. Coast Guard's (USCG) Offshore Vessel Movement Reporting System (OVMRS) which extends 38 miles offshore Mount Tamalpais, shall be used to track barges within its range.
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5.2.10 No more than one disposal vessel shall be present within the permissible dumping target (as described in the following paragraph) at any time.
5.2.11 Dredged material shall be discharged within a 1.1 nautical mile diameter circle centered at 37 39'N, 123ø29'W.
5.2.12 When dredged material is disposed, no portion of the barge shall be further than 3,200 feet from the center of the ocean disposal area.
5.2.13 The Contractor shall maintain daily records of dredging operations, transportation schedules, barge load volumes disposed, and exact location and time of disposal.
5.2.14 The tug captain shall maintain a copy of all weather reports and shall make wind and sea observations.
5.2.15 Each tug boat shall maintain a computer printout from GPS or other approved navigation system showing transit routes and disposal coordinates, including the time and position of the disposal barge when the barge doors open and close.
5.2.16 The Contractor's quality control staff shall observe all dredging operations and submit reports containing a decription of operations for each barge load, a checklist, a transit route map, a printout of coordinates from each waypoint and release point, a record of radio transmission and facsimile from the tug captain on a weekly basis.
5.2.17 The Contractor shall allow observers from the Point Reyes Bird Observatory or other appropriate independent observers as specified in permits to be present on disposal vessels on all trips to the ocean disposal area for the purpose of conducting surveys of seabirds and marine mammals. The Contractor shall ensure that independent observers are present on a sufficient number of vessel trips to characterize fully the potential impact of disposal site use on seabirds and marine mammals. At a minimum, the Contractor shall ensure that independent observers are present on at least one disposal trip in any calendar month in which a disposal trip to the ocean disposal area is made.
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5.2.19 The Contractor shall report any violation to the EPA and the Contracting Officer within 24 hours. In the event of a violation, the Contractor must make all necessary changes to bring disposal operations into compliance before making another trip to the ocean disposal area.
5.2.20 Development and implementation of more sophisticated surveillance systems, which can be demonstrated to the Contracting Officer to be effective and capable of being audited, may be substituted pending approval from the Contracting Officer for one or more of the above provisions.
5.3 Disposal Vessel Location (for Ocean Disposal Area). The Electronic Positioning System (EPS) and methods used for the dredge, as specified under Paragraph "DREDGING", shall also be used to display and record the disposal vessel's location at 1-minute time intervals in the vicinity of the disposal site. Enroute to the disposal area, the EPS shall be activated within 1 nautical mile (NM) of the disposal area and not be deactivated until 1 NM from the perimeter of the disposal area on the return trip. Positional data shall be annotated for the time actual dumping is in progress. The EPS data shall be received on board the actual disposing platform/vessel. Positional data received on board a towing or other vessel adjacent to the other vessel will be allowable provided that (1) the eccentric distance does not exceed 100 feet and (2) the eccentric distance and bearings are relatively consistent/constant on successive disposal operations. In no case will gyro-radar distance/bearing estimations be acceptable for eccentric measurements. In such cases, an electronic data transmitter/telemetry system shall be developed to link the towing or other vessel with the disposal platform/vessel. Eccentric coordinates, if any, shall be clearly identified and computed on the copy of the positional record specified below. A copy record of the positional data, correlated with time and annotated with date shall be submitted to the Contracting Officer as part of the daily Quality Control Report and every Monday before noon on a computer diskette. The Contractor shall also furnish a copy of the computer program for reading the diskettes. The Contracting Officer shall have access to the monitoring equipment in order to observe its operation during disposal operations.
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6. LAND DISPOSAL PLANS. 6.1 General. The Contractor shall furnish the following two documents to the Contracting Officer for approval prior to use of the land disposal sites:
6.2 Off-loading and Transportation Control Plan. The Contractor shall furnish an Off-loading and Transportation Control Pl an describing how the off-loading and slurry pipeline facilities will be designed and operated. The plan shall contain the following elements.
6.2.1 A proposed slurry pipeline design. 6.2.2 An operations and maintenance plan. 6.3 Dredging Quality Assurance Plan. The Contractor shall submit a Quality Assurance (Q/A) plan which describes how dredging will take place and how designated sediments will be dredged and isolated from other sediments. The Q/A plan shall describe the process(s) that will be utilized to ensure that only material deemed acceptable for disposal at the ocean disposal site and Sonoma Baylands placement are dredged and transported to those sites. The plan shall also describe how material designated for disposal at the Galbraith site will be dredged and disposed of. A goal of the dredging Q/A plan is to ensure that material designated for disposal at the Galbraith site does not get accidently dredged for disposal at either the ocean disposal site or Sonoma Baylands. The plan shall reference specific strata and polygons as necessary, and shall provide a description of dredging equipment to be used and the performance and limitations of such equipment in dredging isolated materials.
DISPOSAL AT SONOMA BAYLANDS. 7.1 General. Dredged material designated on the drawings shall be unloaded by pumping and deposited in the Government-furnished land disposal area at Sonoma Baylands as shown on the drawings. The disposal site shall be filled in sections as shown on the drawings up to the initial fill elevations in accordance with Paragraph "Initial Fill Elevation". The discharge end of the pipeline shall be baffled to uniformly distribute slurry and prevent erosion. During the disposal operations, a freeboar of not less than
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7.2 If the capacity of the disposal site is reached before disposal operations are complete as determined by the Contracting Officer, the remaining dredged material designated for disposal at Sonoma Baylands shall be disposed of at the ocean disposal area. Measurement and payment will be in accordance with Paragraph "MEASUREMENT AND PAYMENT", except that payment for that material will be paid for at the same contract unit price for item, "Dredge & Dispose of Material in Ocean Disposal Area (Excluding Berth Areas)".
7.3 Initial Fill Elevation. The "initial fill elevation" for dredged material means the elevation of the sediment surface (sediment-water interface) during the discharge of dredged material into a particular section of disposal site. For each section of the Sonoma Baylands disposal area as shown on the drawings, the Contractor shall deposit the dredged material from the designated polygons up to the initial fill elevation as determined by the Government.
7.3.1 For each section, the Government will provide to the Contractor the initial fill elevation required to achieve the final design elevation of +2.0 feet NGVD after consolidation. The initial fill elevation will be based on the physical characteristics of dredged material previously placed by the Contractor and the anticipated physical characteristics of the remaining dredged material to be placed in each section, as determined by the Government.
7.3.2 The Government may revise the initial fill elevation for a section if the actual dredged material elevation in the section is no greater than +2.0 NGVD as determined by the Government.
7.3.3 If 48 hours have elapsed since a section was last filled, the Government may revise the initial fill elevation to account for consolidation of the previously placed material. In the section(s) where dredged material is being deposited, the Government will furnish the elevation(s) of the dredged material at the instrumentation post(s) no later than 48 hours after receipt of written request from the Contractor.
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7.5 Effluent Weirs. All effluent weirs used for drainage at the disposal area shall be maintained by the Contractor at no additional cost to the Government. It shall be the responsibility of the Contractor to adjust his operations to permit settling of solids in compliance with subparagraph "Waste Water Quality Control," below. Upon completion of the dredging and drainage of the disposal areas, effluent weirs shall remain in place.
7.5.1 Site Drainaqe. At the completion of the disposal operations, the Contractor shall be responsible for draining the site leaving a minimal amount of water so as to not substantially dry out the dredged material, but allow for dessication; drainage shall be at the direction of the Contracting Officer. The period of time for dewatering shall extend until tidal action is restored, and is expected to be a minimum of 6 months and a maximum of 12 months as directed by the Contracting Officer. During this period of time, all discharge over the weir will be subject to the waste water quality control requirements as specified in the contract.
7.6 Waste Water Oualitv Control. All discharge from the disposal area shall be made over effluent weirs and such discharge shall be subject to the waste water quality control requirements specified in Paragraph "WATER POLLUTION CONTROL" in Section "ENVIRONMENTAL PROTECTION". The Contractor shall construct his own access walkways from the impounding levees to the points of discharge where samples are required to be taken. Access shall minimize disturbance to native habitatf including the clapper rail habitat, as specified in Section "ENVIRONMENTAL PROTECTION" and shall be included in the environmental protection plan. Whenever measurements indicate that the discharge from the disposal area is not satisfactory, the Contractor shall take the
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7.7 Protection of Instrumentation. The Government has installed electronic test instrumentation within the project disposal site to determine dredged material densities and elevations by resistivity measurements. The equipment includes resistivity strips mounted on 8-inch diameter polyvinyl chloride pipe posts with guy wires and interconnecting wiring where indicated on the drawings. The Contractor shall not disturb the equipment and wiring during his operations.
7.8 Final Grade Tolerance. The Contractor shall conduct his disposal operations to limit mounding of the dredged material in the disposal site. Tolerance of the elevation of the sediment after completion of disposal operations in each section of the disposal area shall meet the following requirements: (1) the average actual initial fill elevation in each section shall be within + 0.5 foot of the specified initial fill elevation for that section; (2) the elevation of the dredged material throughout each section shall be within + 1 foot of the specified fill elevation for that section. If mounding exceeds the above specified tolerances, the Contractor shall take whatever actions are necessary to meet the requirements, at no additional cost to the Government.
7.9 Disposal Operation Records. The Contractor shall prepare and maintain daily records of his disposal operations at the Sonoma Baylands disposal site until disposal operations at this site are complete. The information contained in each daily record shall include a drawing which shows the location of each pipe discharge point within the disposal site; date, starting and ending times of deposition of dredged material from each discharge point; and a list of the designated polygons that were the source of the dredged material discharged at each discharge point. These records shall be submitted to the Contracting Officer as part of the daily Quality Control Report.
8. DISPOSAL AT GALBRAITH UPLAND SITE. 8.1 General. The Galbraith disposal area will not be available for disposal until 1 June 1995. Disposal shall be in 2 stages. The Contractor shall coordinate his work through the Contracting Officer with others working at the disposal site who will be sampling, testing and monitoring the effluent, decanting water, and monitoring the dikes.
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8.3 Stage 2. Stage 2 disposal of the remaining material designated for disposal at this site shall not commence until 180 days after Stage 1 disposal is completed, to allow for decanting of surface water, heightening of the containment dikes (up to +28' MLLW), and partial drying of the Stage 1 material by others. The total estimated capacity of the site (Stage 1 and Stage 2) is 1,883,000 cubic yards (926,000 cy and 957,000 cy), excluding freeboard volume.
8.4 Turning Basin Material. Disposal of the material dredged from the Inner Harbor turning basin shall not commence until at least 100,000 cubic yards of other material requiring upland disposal has been placed into the cell(s) which will be used for disposal of the turning basin material. Subsequent to disposal of the turning basin material at least 100,000 cubic yards of other material shall be placed over the turning basin material.
8.5 Decanting Disposal Site. The Contractor shall employ pumps and/or siphons as necessary to remove any standing surface water to the decant weir points or from one pond to the other. The Contractor shall be responsible for managing the placement and dewatering of the dredged material and for scheduling the delivery of dredged material to accomodate all of the material designated on the drawings for disposal at this site.
8.6 Hydraulic PiPeline. The hydraulic discharge pipeline shall be made of steel. The pipeline shall be equipped with an approved mechanical and/or electrical device which will cause an immediate shutdown of the pump at the offloading platform in the event of breakage or leakage along the pipeline. The pipeline from the unloading platform to the disposal site shall be placed within the alignment limits shown on the drawings. In water areas, the pipeline shall be a floating pipeline. Over land areas the pipe shall be above ground, except where the pipeline crosses under roads. The pipeline shall be visible for public safety by marking the pipeline by installing warning signs or buoys and will be illuminated at night by a series of lights along the entire alignment of the pipeline, as approved. The Contractor shall ensure that the pipeline does not create a navigational or public hazard and does not block access to or in navigation waterways. The slurry discharge pipe shall be relocated as necessary to achieve uniform filling of each of the ponds, to prevent excessive shoaling of the dredged material and to
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8.7 Access from San Leandro Bay (Alternate 1). Access for the discharge pipeline runs from San Leandro Bay to the disposal site shall be along the alignment shown on the drawings. The Contractor shall furnish a plan showing the alignment of the pipeline and the installation details. The plan shall include pipeline anchorage; compliance with traffic regulations; details of trail and road crossings; location, size and installation details of booster pumps; details of unloading platform including location, equipment, size and installation; and restoration.
8.7.1 Regional Park Trail. Where the pipeline crosses the East Bay Regional Park trail, public access shall be maintained by trenching and burying the pipeline through the trail or by providing a ramp over the pipeline. The ramp shall meet the requirements of the American Disabilities Act, as approved.
8.7.2 Roads and Highwav. Pipe installation across Highway 61 shall be by boring and jacking the pipe under the highway. Pipe installation across roads shall be by boring and jacking the pipe under the roads or by trenching and burying the pipeline. The Contractor shall close only one traffic lane at a time and provide traffic control. A traffic control plan shall be prepared in coordination with local and State traffic authorities and submitted to the Contracting Officer. The location of public utilities will be available for review at the Port of Oakland office. The roads and highway shall be restored to their original condition after completion of the disposal operations.
8.8 Access from San Francisco Bay (Alternate 2). Access for the discharge pipeline runs from San Francisco Bay to the disposal site shall be along the alignment shown on the drawings. The Contractor shall furnish a plan of the alignment of the pipeline and the installation details. The plan shall include compliance with Oakland International Airport and Federal Aviation Administration air traffic regulations including height limitation of construction equipment near runways; pipeline installation; pipeline anchorage; details of road crossings; location, size and installation details of booster pumps; location, equipment, size and installation details of unloading platforms; and restoration. Attention is directed to Appendix 10 and 13 for FAA requirements and Oakland International Airport requirements, respectively.
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8.10 Disposal. Dredged material shall be unloaded by pumping and deposited in the Galbraith disposal area as shown on the drawings. The discharge end of the pipeline shall be baffled to uniformly distribute slurry and prevent erosion. The pipeline shall be moved as directed to allow even and uniform distribution of material in both holding ponds and to prevent excessive loading against the levees. During the disposal operations, a freeboard of not less than one (1) foot shall be maintained between the top of impounding levees and the water surface at all times. Upon reaching the freeboard limit, the Contractor shall stop pumping into the disposal area and shall allow sufficient time for drainage and settlement of solids before additional material is deposited in the disposal area.
8.11 Waste Water Ouality Control. All discharge from the disposal area shall be subject to the waste water quality control requirements specified in Paragraph "WATER POLLUTION CONTROL" in Section "ENVIRONMENTAL PROTECTION". The Contractor will not be responsible for sampling and testing, which will be performed by the Port of Oakland. In the event that the discharge does not meet water quality requirements, the Contracting Officer will notify the Contractor to alter or suspend his operations. The Contractor shall allow for a period of 20 days during each stage of disposal when the discharge may be required to be suspended at the disposal site for alterations to assure compliance with the waste discharge requirements, at no additional cost to the Government.
9. DISPOSAL OF DEBRIS. Debris, man-made objects, timber, chains, anchors, flotsam, miscellaneous metal objects and other foreign material encountered within the dredging prism during the dredging process shall not be disposed of in the Government-furnished disposal areas. Such material shall be placed in a separate barge or other conveyance and disposed of outside the limits of the work and on a land disposal site in accordance with local, State and Federal laws and regulations.
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11. OVERDEPTH AND EXCESSIVE DREDGING. 11.1 Overdepth for Channel and Turning Basin Wings. Except as specified hereinbelow, overdepth will be as follows: 1) For polygons of soft material an overdepth of one (1) foot will be allowed; 2) for polygons of hard material a required overdepth of one (1) foot plus an allowable overdepth of one (1) foot will be allowed; and (3) for polygons - containing both hard and soft material a required overdepth of one (1) foot plus an allowable overdepth of one (1) foot will be allowed. "Required overdepth" must be dredged by the Contractor. "Allowable overdepth" is tolerance to assure removal of a sufficient amount of material to reach project depth and width and may be dredged by the Contractor.
11.2 Overdepth for Berth Material. An overdepth of one (1) foot will be allowed for berth areas.
11.3 No payment will be made for materials removed from beyond the neat line template payline shown on the drawings. Materials sloughing into the payment area from outside the neat line side slopes shall be removed at no additional cost to the Government. Overdepth dredging will not be allowed under side slopes and where dredging to achieve required project depth is not performed.
11.4 Excessive Dredging. Dredging shall not be performed below the allowable overdepth. If excessive dredging occurs, the Contractor shall report the locations of excessive dredging and the quantities to the Contracting Officer. The Contractor may be subject to sanctions by Federal, State and local agencies for excessive dredging.
12. REPORTING REQUIREMENTS. The Contractor shall be required to prepare and submit daily reports of operations on quality control forms as directed and/or accepted by Contracting Officer. Sample forms are shown in the Appendixes at the end of this section. The daily reports which may be supplemented with hydrographic survey cross-sections shall document dredging operations for all shifts in a 24-hour period. Further instructions on the preparation of the reports will be furnished at the pre-dredging conference.
02480-19
14. MEASUREMENT AND PAYMENT. 14.1 Measurement for Payment. Measurement for payment of the total amount of material dredged will be made based on the cubic yards of material in-place, by computing the volume between the bottom surface shown by soundings of the Contractor's survey taken before dredging and the bottom surface shown by soundings of the final survey compared with the neat line template, using the average-end-area method. This quantity shall include excavation performed within the allowable overdepth limits and exclude excessive dredging as specified under paragraph "OVERDEPTH AND EXCESSIVE DREDGING".
14.2 The contract drawings represent conditions existing on the date of the survey shown on the drawings and are for information purposes only. The pre-dredge survey performed by the Contractor will be used in determining quantity of material for payment. Determination of quantities removed and the deductions made therefrom to determine quantities by in-place measurement to be paid in the area specified after having once been made will not be reopened, except on evidence of collusion, fraud or obvious error. No payments will be made until all computations, field notes and drawings are received for progress payment.
14.3 Payment for dredging will be made at the applicable contract unit prices bid under the following items:
"Dredge Outer Harbor & Dispose of Material in Ocean Disposal Area" 02480-20
14.4 Shoaling. Shoaling occurring within the project limits after acceptance of any polygon and prior to the completion of the contract shall be removed if directed by the Contracting Officer. Such work will be subject to the "CHANGES" clause.
SAFETY IS A TEAM EFFORT 02480-21