35 20 23 Dredging R0001 (25B0008).pdf

FY25 Everett Hydraulic Dredging 25009 Everett, WA

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SECTION 35 20 23

DREDGING

UFGS 08/20; NWS NAV 10/24

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

CODE OF FEDERAL REGULATIONS (CFR)

33 CFR 83.30 Vessels Anchored, Aground and Moored Barges

U.S. ARMY CORPS OF ENGINEERS (USACE)

EM 385-1-1 (2024) Safety -- Safety and Occupational Health (SOH) Requirements

EM 1110-2-1003 (2013) Engineering and Design -- Hydrographic Surveying

1.2 GENERAL INFORMATION

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

1.3 DEFINITIONS

1.3.1 Maintenance Material

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

1.3.2 New Work Material

New work material is defined as previously undredged material.

1.3.3 Dredge Prism

The Dredge Prism is the box cut (toe to toe) channel from existing surface to Required Dredging Depth, not to exceed Maximum Dredging Depth.

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1.3.4 Required Dredging Depth

The Required Dredging Depth is the authorized project depth within the Dredge Prism.

1.3.5 Allowable Overdepth (OD)

The Allowable Overdepth (OD) is to cover inaccuracies of the dredging operation within the dredge pris. Overdepth dredging is allowed as specified in paragraph OVERDEPTH DREDGING to ensure Required Dredging Depth is achieved.

1.3.6 Allowable Advance Maintenance (AM)

Advanced maintenance dredging is not authorized for this contract.

1.3.7 Maximum Dredging Depth

The Maximum Dredging Depth is the cumulative sum of the Required Dredging Depth, plus Allowable Overdepth. This is a not-to-exceed dredging depth, within the Dredge Prism. Dredging beyond this depth is considered excessive dredging and corrective action (physical and/or financial costs) is solely the Contractor’s responsibility.

1.3.8 Minimum Pay Depth

The Minimum Pay Depth within the Dredge Prism that will be considered for payment (required depth).

1.3.9 Maximum Pay Depth

The Maximum Pay Depth within the Dredge Prism that will be considered for payment (required depth plus Allowable Overdepth.)

1.4 SUBMITTALS

Government approval is required for submittals with a "G" classification. Submittals not having a "G" classification are For Information Only (FIO). Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Work Plan (WP); G List of Proposed Subcontractors; FIO List of Proposed Equipment; G

SD-02 Shop Drawings

Pipe Specifications

1.5 METHOD OF COMMUNICATION

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

1.6 OTHER OPERATIONS

There may be other marine construction projects near the project work area, which may occur simultaneously with this project. These projects are managed by local entities and governmental agencies. Accordingly, information concerning these projects is limited to non-existent. It is the

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Contractor’s responsibility to obtain relevant information and plan accordingly. No additional payment will be made for delays due to channel activities.

1.7 PROTECTION OF EXISTING WATERWAYS

Conduct dredging operations using a method that ensures material or other debris are not pushed outside of the dredging limits or otherwise deposited in existing side channels, basins, docking areas, or other areas being used by vessels.

1.8 WORKING ENVIRONMENT

1.8.1 Site Related Weather and Tidal Conditions

Perform work with the understanding of hazards likely to arise from the weather conditions during the construction period. The following websites provide weather forecasts, records and reports and data concerning historic and oncoming storms and tides at the worksite:

https://tidesandcurrents.noaa.gov/tide_predictions.html?gid=1415#listing https://www.weather.gov/sew/Marine_SEW

1.8.2 Managing Work to Match Weather and Oceanographic Conditions Implement measures to reduce risks of damage to in-progress work elements, associated with periods of high tide, winds, waves, currents, or storms. Protect vulnerable work elements during active construction periods and during non-construction periods. Do not progress beyond a vulnerable in-progress work component without being able to secure that component before exposure to a damaging event (high tide, storm condition, etc.). Maximize opportunities to perform work on vulnerable work elements when favorable conditions are available and avoid exposure to damaging events. Repair damage to any in-progress work caused by environmental processes at the expense of the Contractor.

1.8.3 Shallow Channel

There are areas outside of the project dredging area, and downstream of the contract dredging area, which are shallower than the authorized navigation channel depths. It is the responsibility of the contractor to evaluate the depths and clearances on the hydrographic surveys and drawings and to account for the controlling depths in the project execution of their dredging and disposal operations.

1.9 WORK PLAN

The Contractor shall submit a Work Plan within fourteen (14) calendar days of Notice to Proceed (NTP).

The Contractor’s Work Plan shall include a description of mobilization/demobilization, document and describe the proposed equipment, means, and methods of accomplishing the dredging, handling, and disposal of sediment and debris. The Work Plan shall describe the proposed survey controls (horizontal and vertical i.e., depth) that shall be utilized to demonstrate that dredging is being completed in accordance with the design dredging prism. Additional plans related to the work includes a Disposal Plan and shall be included as separate section in the Work Plan. The Work Plan shall describe the Contractor's plan to execute and complete this project, to include, but not limited to schedule, equipment, means and methods for dredging and disposal.

https://tidesandcurrents.noaa.gov/tide_predictions.html?gid=1415#listing https://www.weather.gov/sew/Marine_SEW

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The Work Plan includes, but is not limited to, the following elements:

a. General project description and information, list of any proposed Subcontractors, list of employees (prime and primary subcontractor(s)) including role and responsibilities, equipment (prime and subcontractor(s)). A description of the organization, including a chart showing lines of authority and acknowledgment. Include a Project Superintendent, CQC System Manager, site health and safety representative, equipment operator(s), and other key personnel deemed necessary by the Contractor for the successful implementation and completion of this work.

b. Description of the means and methods to complete the required work. Prepare a work area plan showing the proposed activity in each portion of the repair area(s) and identify the areas of limited use or nonuse. Include measures for marking the limits of use areas, including methods for protection of features to be preserved within authorized work areas and methods to control runoff and to contain materials on site, severe weather plan, a site plan, and a traffic/pedestrian control plan.

c. Other elements to include are task sequencing including demonstration section completion and approval, description and figures of work areas, equipment details and use, site management (civilians, traffic, visitors, etc.), approved techniques, loading methods, transportation methods, surveying and mapping plan, proposed temporary excavations or embankments for haul roads, stream crossings, jurisdictional wetlands, material storage areas, structures, sanitary facilities, storm drains and conveyances, and stockpiles, disposal facility, equipment and cleanup plans, maps of facilities and emergency contact information. Content can be narrative, charts, tables, drawings, and/or figures.

d. Contact information (Contractor(s)/subcontractor(s) and government), emergency information, lines of communication between Contractor(s), subcontractor(s), and government. Provide 24-hour direct telephone numbers for key staff that will be responsible during off hours work periods and on non-working days.

1.10 GOVERNMENT RECORDS

Records of previous dredging, previous Before-Dredge (BD) and After-Dredge (AD) bathymetric surveys, detailed current condition bathymetric surveys, are available at the eHydro survey data site:

https://www.arcgis.com/apps/opsdashboard/index.html#/4b8f2ba307684cf597617bf1b6d2f85d

1.11 SURVEY

1.11.1 Existing Condition Surveys and Cross-Sections

a. Drawings shall be provided electronically by the Government via email or other electronic methods, such as the Government’s file transfer site, after the Notice to Proceed (NTP).

b. Government-provided drawings are believed to accurately represent conditions existing at the time of the survey. There may be unidentified conditions; it is the Contractor’s responsibility to verify conditions.

c. Government-provided drawings showing existing condition surveys and cross-section sheets are for information only.

https://www.arcgis.com/apps/opsdashboard/index.html#/4b8f2ba307684cf597617bf1b6d2f85d

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1.11.2 Quantity Surveys

a. The Government shall perform bathymetric surveys of the dredged work area for any periods during which progress payments are requested. Volume computations shall be based on these surveys. Bathymetric surveys will be conducted at a frequency no greater than once every two weeks (fourteen (14) calendar days) but may occur more frequently at the discretion of the

COR.

b. Failure by the Government to adhere to these bathymetric survey schedules shall not be the basis for a claim by the Contractor or Subcontractor(s) for extra compensation for any reason.

Additional bathymetric surveys can be requested by the COR if/when unusual circumstances arise.

c. Hydrographic surveys will be conducted by the Government to meet USACE Performance Standards as defined in EM 1110-2-1003. Surveys will be conducted utilizing depth sounding and horizontal positioning equipment. Sounding depths will generally be derived utilizing multi-beam or single-beam acoustic methods. However, the Government reserves the right to take soundings by any method, including lead line or trigonometric leveling (total station)/differential leveling. The same method will be used for the before dredge (BD), progress, and after dredge (AD) surveys of a given pay area.

d. Cubic yard volumes will be computed by comparing the Government's bathymetric soundings against the channel design template. The Government intends to use a current version of Hypack or Bentley OpenRoads Designer CE to compute pay volumes. Computed pay volumes will be the difference between the computations of the BD and AD surveys. Volumes may be computed by comparing the Government's bathymetric progress soundings against other progress surveys, or an after-dredge survey, but only at the COR’s discretion.

e. All Contractor owned equipment including all attendant plant, pipes and anchor lines in the survey area must be removed from the acceptance area prior to the initiation of all BD and AD dredge surveys. Any failure by the Contractor to remove attendant plant, pipes and anchor lines in the survey area may result in the postponement of the Government survey.

f. All surveys conducted by the Contractor shall be in accordance with the EM-1110-2-1003.

Accuracy(ies) will be in accordance with stated quality control values in EM-1110-2-1003.

g. The Contractor is responsible for requesting Government BD and AD surveys of all work areas.

The request shall be submitted in writing to the Government representative(s) identified at the pre-construction conference. The Government Survey periods stated above are contingent on availability of government equipment, weather, and sea conditions.

h. In the event it becomes necessary to reschedule a request for survey, the Contractor shall notify the Government at least two (2) working days prior to the first day of the scheduled survey period.

i. All depths obtained from multibeam surveys will be utilized for volume computation purposes.

Multibeam surveys will use a 2-foot-by-2-foot matrix using the median depth of all depths recorded in a cell will be generated from the edited multibeam data to perform the TIN volume computations, following the procedures outlined in EM 1110-2-1003. Any corresponding plotted plan view sounding sheets depicting representative depths over a dredging project will be generated using a cell size that is plot-scale dependent, utilizing a randomly selected

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sounding that is closest to cell center (shot depth) shifted to the center of the cell from the edited multi-beam data, as described in EM 1110-2-1003. All edited/processed bathymetric survey data (xyz) used for volume computations shall be made available to the Contractor upon request.

j. No separate payment will be made for impacts associated with these surveys.

1.11.3 Dispute of Surveys Performed by the Government

If the Contractor disputes the accuracy of any survey performed by the Government, the Contractor shall immediately notify the COR in writing, concerning the nature of the dispute. If the dispute cannot be resolved immediately, the Contractor shall immediately resurvey the shoal using multibeam, or all remaining area not been dredged or unaffected portions of the shoal with a Government representative onboard the Contractor’s survey boat. At the conclusion of the survey, the Contractor shall provide copies of all raw and edited data files for that shoal. The files shall be in Hypack format.

The Contractor shall submit the following information (as a minimum) in support of the survey data:

a. Edited survey data in xyz format (2x2 and 5x5 matrix); coordinates shall be Washington State Plane Coordinates, North American Datum (NAD) 1983/2011.

b. Method of horizontal and vertical positioning used (RTK or Tide Gauge).

c. Date, time, and stage of tide.

d. Water surface conditions.

e. Plan drawing in pdf format showing the edited depth soundings.

f. Plotted cross sections of the latest Contractor survey compared with the Government survey.

The individual cross sections shall be performed at 25 feet increments.

g. Plan drawing in pdf format of channel showing areas that were worked by the dredge.

h. Speed of sound through the water column in area of survey and method used to determine the speed of sound.

i. Draft of survey boat and method used to determine the draft.

j. A table listing the status of all calibrations to include patch performance test area designated by the COR and required by EM 1110-2-1003, and the date equipment was set up and last checked.

The Government will evaluate the data provided by the Contractor and use this information to evaluate and make a determination of the dispute.

1.12 SHOALING

If, before the Contract is completed, shoaling occurs in any section previously accepted, including shoaling in the finished channel, because of the natural sloughing of the side slopes, re-dredging at contract price, within the limit of available funds and time, may be done if agreeable to both the Contractor and the COR.

PART 2 PRODUCTS

2.1 CHARACTER OF MATERIAL

The maintenance material to be removed is sand, silt, clay, and incidental gravel from shoaling that has occurred since the channel was last dredged. Classification and description of the materials to be

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dredged is classified according to U.S. Geologic Survey (USGS) Wentworth Grade Scale (Attachment 35 20 23-A).

The Contractor may encounter accumulations of woody debris, sunken logs, stumps, snags, whole trees with root systems, fishing debris, and miscellaneous debris. Contractors shall examine the site of work and verify the character of materials prior to the start of dredging. The Contractor is ultimately responsible for determination of the characteristics of materials to be dredged.

PART 3 EXECUTION

3.1 INSPECTION

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

The Contractor shall record times, durations, and reasons of all shutdowns during the dredging period.

See Section 01 45 00 QUALITY CONTROL and Section 01 45 00.15 RESIDENT MANAGEMENT SYSTEM CONTRACTOR MODE (RMS CM) for reporting requirements. Contractor shall prepare and maintain a daily report package of operations and submit via RMS and furnish one electronic copy to COR daily.

Further instructions on preparation of the report package will be furnished at the preconstruction conference.

On the request of the COR or any inspector, allow the Government to temporarily install a construction camera, provided by the Government, on the dredge vessel. In general, the location provided shall provide for a 360-degree viewpoint permitting the observation of the crane deck and dredge barge.

The mounting point shall consist of a wooden or metal stanchion, a minimum of 3 inches in diameter, but not greater than 6 inches in diameter. In addition, the contractor shall provide a source of electrical power consisting of 110v, 20 Amp. Power for the camera must be provided at all times the vessel is dredging and when scow filling activities are occurring. Mounting location shall be agreed upon after contract award. Contractor shall be given access to the camera’s web-based video feed.

At the Government’s discretion, if the Government designated QA representative is unable to be physically present on the Contractor’s plant to verify the CQC procedures, the Contractor must provide real time video capability for the Government to perform inspections, witness tests, participate in meetings, and other tasks of a similar nature. Anticipate these efforts may take up to 3 hours each week.

At the Government’s discretion, QA equipment inspections may be completed from a distance using electronic methods such as a video chat or live-time video call (compatible with Government cell phones or computer). The Contractor must provide real time video, if requested by the Government, for the Government to perform the inspection remotely, and anticipate the inspection may take up to 3 hours each week.

No separate payment will be made for impacts associated with Government QA inspections.

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3.2 STAGING AREAS

Contractor shall obtain and coordinate location of staging areas with the property owner(s). After the Contractor completes their operations, the staging area shall be restored to a condition equal to or better than existed prior Contractor’s operations. Government will not be responsible for Contractor’s equipment and materials in the staging area and Contractor shall provide his own security.

3.3 DREDGING

3.3.1 Order of Work

Dredging sequencing will be discussed during the preconstruction meeting prior to the start of mobilization. The Contractor shall annotate the sequence of work in their Work Plan. The Government reserves the right to change the order of work at any time. The Contractor must submit a revised Work Plan and receive COR approval before deviating from a previously approved sequence of work.

3.3.2 Dredge Plant and Equipment

A hydraulic dredge will be used to perform all dredging work under this contract.

Furnish and maintain all dredge plant and associated equipment such as, but not limited to, scows, coamings, barges, and pipelines, to meet the requirements of the work. Promptly repair leaks or breaks.

During construction, the operation of heavy equipment shall be held to the minimum necessary within all intertidal and nearshore areas. Alteration or disturbance of existing beach and intertidal vegetation shall also be held to a minimum.

Keep all necessary dredge equipment and attendant plant, and equipment on the job to meet the requirements of the work. The dredge equipment, attendant plant and other equipment shall be in satisfactory operating condition, capable of safely and efficiently performing the work as set forth in specifications and shall be subject to inspection by the COR.

3.3.2.1 Horizontal Positioning

Dredging and material placement plant shall be positioned using a differential GPS with an accuracy of +/- 3 feet. The system shall be used to ensure that dredging is performed within the designated pay area(s) and that material will be evenly distributed within the dredged material placement areas, as shown. Any delay or suspension for noncompliance of this requirement will be at no cost to the Government nor shall it be considered grounds for a time extension.

3.3.2.2 Hydraulic Dredging

a. Dredging shall be accomplished by a 12-inch inner diameter or larger diameter (measured at the discharge pipe), hydraulic pipeline “mechanical” cutterhead suction dredge. “Mechanical” refers to the method of agitation or breaking up of consolidated bottom sediment. Water jets or augers (including horizontal cutterhead) are not acceptable alternatives. The dredge must have the ability to efficiently pump the material to the placement area(s) as described these plans and specifications. Contractor shall submit pipeline specifications for government approval.

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b. Hydraulic Cutterhead Pipeline dredge plant must perform all dredging work under this contract. The Contractor shall furnish all support equipment needed to successfully complete the job. This equipment includes tending vessels, anchors, deck machinery, winches, pumps, and any other equipment needed to meet the contract requirements.

c. Dredges shall be furnished, at all times with an operating and easily readable dredging depth indicator.

d. Pipelines shall not be permitted to fluctuate between the water surface and the channel bottom or lie partially submerged in accordance with EM 385-1-1.

e. Work in and near the Snohomish River and Puget Sound shall be done to minimize turbidity, prevent erosion of existing nearshore and beach areas, and prevent other water quality impacts. Dredging shall be performed in such manner that shall not exceed water quality requirements as stated in the project’s Department of Ecology Water Quality Certification. Best management practices shall be used to minimize turbidity at the dredging and placement sites.

The contractor will be asked to provide a description of Parcel “O” dewatering management with an emphasis on minimizing turbidity in return flows to the Snohomish River and preventing riverbank erosion.

f. Contractor shall meet Chapter 173-201A WAC “Water Quality Standards for surface waters of the State of Washington”.

g. Dredging outside of the contract dredge area is not allowed. In addition, dredges shall be furnished at all times with an operating and easily readable dredging depth indicator.

h. The placement/disposal area boundaries shown on the contract PLANS represent the overall boundaries that the Contractor may conduct placement/disposal operations. The placement/disposal boundaries shall be staked in the field by the Government. The Contractor shall ensure material is not placed outside of the staked disposal areas.

3.3.2.3 Lights

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

3.3.2.3.1 Hydraulic Dredging Lights, Lighted Buoys and Dredging Aids Markers All lights, lighted buoys and dredging aids markers must be maintained, operable and on station at all times to insure a safe harbor. The placement, markings and lighting shall meet all US Coast Guard Regulations, EM 385-1-1 and the Special Requirements found in this specification.

All marker buoys shall be painted yellow and display the same yellow flashing light as required for floating or supported dredge pipelines meeting the requirements of this subsection.

Buoys used to anchor booster pumps.

Buoys used to anchor, or mark stored equipment i.e. (barges, pipeline etc.).

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Buoys used to mark or anchor dredge pipelines, and this includes floating and submerged pipeline leading to placement areas.

Any other buoys the U.S. Coast Guard requires to ensure a safe harbor free from hazards to navigation must be marked and display yellow flashing lights meeting the requirements stated in this subsection.

3.3.3 Interference with Navigation

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

3.3.4 Temporary Removal of Aids to Navigation

The Contractor shall inform the COR at least fourteen (14) calendar days in advance of any necessary temporary removal or relocation of channel markers to facilitate dredging operations. This notification allows the U.S. Coast Guard to carry out the required work and ensures that navigation interests are adequately informed ahead of the proposed changes.

3.3.5 Navigation Warnings

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

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

Display a sturdy and prominent warning sign at all public boat marinas within 10 miles of dredging operations or moored equipment. The Contractor is responsible for keeping this sign current with respect to the dredging operations or equipment.

3.3.6 Tidal Reference

Prior to beginning dredging, the Government will establish a tidal reference point on one navigation aid on each reach affected by the dredging. The Contractor shall use the reference points for their elevation control. Centerline range alignment may vary from the channel alignment. Contractor’s use of ranges for positioning shall be at their own risk; see FAR Clause 52.236-17 LAYOUT OF WORK.

3.3.7 Layout of Work

The Contractor will be provided PLANS for all dredging areas and/or the results of Government hydrographic survey monitoring. The most current Government hydro survey information is available as described in paragraph GOVERNMENT RECORDS. All depths are measured from mean lower low water (MLLW). Other pertinent information to be included with the PLANS: required and Maximum Dredging Depths, coordinates for the material placement site, distance one-way from dredging location to placement site, specific placement site instructions, supplemental tide gauge information, horizontal control locations, and computed hydro survey quantities.

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The Contractor shall dredge available material from the work area necessary to complete the work specified. The Contractor shall not exceed the estimated quantities in the awarded Contract bid line items without prior specific authorization, and only with a signed contract modification issued by the Contracting Officer. The work shall be performed in accordance with this Contract and at the Contract Line Item price(s). The quantities listed are estimates only. All estimated quantities are subject to FAR Clause 52.211-18 VARIATION IN ESTIMATED QUANTITY.

3.3.7.1 Overdepth Dredging

To cover unavoidable inaccuracies of dredging processes, material actually removed to a depth of 2 feet below the minimum required depth specified and within the dredging limits will be measured and paid for at full contract price.

3.3.7.2 Side Slopes and End Transitions

Side slopes for channel reaches are provided on the contract PLANS. End transitions shall match the immediate side slope of the area dredged.

Dredging shall only be from toe of slope to toe of slope (box cut between toes). Estimated quantity does not account for material in the side slopes. However, the material in the side slope and end transitions may displace into the box while dredging. If side slope or end transition material displaces at any time (prior to acceptance) during the work window, it is the responsibility of the Contractor to clear the channel to Minimum Pay Depth. The amount of material displaced from side slopes and end transitions as defined in the PLANS shall be determined by bathymetric survey and will be paid.

Dredge sloped end-cut transitions from existing channel depth to Required Dredging Depth.

3.3.8 Obstructions and Debris

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

If actual conditions differ from those stated or shown, or both, either scope of work will be adjusted to accommodate the obstruction or an adjustment in contract price or time for completion, or both, may be made in accordance with FAR Clause 52.236-2 DIFFERING SITE CONDITIONS.

The Contractor may encounter accumulations of forest trash, sunken logs, stumps, man-made wood products, wire and synthetic rope, metal debris, fishing nets, tires, and other miscellaneous natural and man-made debris. No natural or artificial debris greater than two (2) feet in any dimension is allowed in the open water or upland placement/disposal sites. Debris greater than two (2) feet in any dimension, caught in the dredging operations shall be removed from the dredged material prior to placement/disposal, placed on deck and disposed in an appropriate upland disposal facility. All debris collected during the dredging operations destined for placement/disposal shall be disposed of by the Contractor, at the Contractor’s expense, at a facility authorized to receive the material. Debris collected shall be collected, handled, and disposed in accordance with Section 01 57 19 TEMPORARY

ENVIRONMENTAL CONTROLS.

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No additional payment shall be made for disposal of debris and shall be considered incidental to the dredging operation.

3.3.9 Dredging Requirements

As determined by the results of hydrographic survey monitoring, the Government will direct the Contractor to dredging sections as follows:

Section/Reach Station Required Dredging Depth (ft MLLW)

Allowable Overdepth (OD) (ft)

Maximum Dredging Depth (ft MLLW)

Min/Max Pay Depths (ft

MLLW)

Lower Channel Sta. 65+00 to Sta.78+00

-15 2 -17 -15/-17

Upper Settling Basin Sta. 337+07 to Sta. 354+47

-20 2 -22 -20/-22

Material placement is detailed in paragraph PLACEMENT OPERATIONS.

3.3.10 Dredging Restrictions

The Contractor shall comply with all water quality requirements as specified in Section 01 57 19

TEMPORARY ENVIRONMENTAL CONTROLS.

The Contractor shall not perform in-water work until all preconstruction submittals are approved by the Government.

Dredging beyond the Maximum Dredging Depth in any section is not allowed. Advance Maintenance is not authorized for this dredging event.

The contractor shall verify the Tribal fishing schedule prior to performing dredging operations. See Section 01 11 00 SUMMARY OF WORK, paragraph TRIBAL COORDINATION.

No in-water work is authorized outside of the specified in-water work window as specified in Section

01 57 19 TEMPORARY ENVIRONMENTAL CONTROLS

Where pre-dredge bathymetric surveys show conditions at or below the required dredging prism, no dredging shall be performed unless approved by the COR.

The time stated for completion shall include final cleanup of the premises.

3.3.11 Excessive Dredging and Corrective Action

Contractor shall be responsible for all Corrective Action, either required by the Government or regulating agencies. Corrective Action includes both physical corrections and financial corrections (cost

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of actual action at both the area dredged and at the placement/disposal site(s), as well as any, fines or other financial penalties levied against the project, the Government, and/or the Contractor.

Soundings or sweepings will be taken by the Government to determine if material has been removed outside the contract limits.

The Contractor shall use extreme care when conducting dredging operation in the channel not to exceed the Maximum Dredging Depth or dredge outside the specified Dredge Prism for each section.

The Contractor shall bear sole responsibility for any dredging beyond Maximum Dredging Depth or Dredge Prism, which may occur because of its operation.

Material taken from beyond the Dredge Prism limits as defined in DREDGE PRISM, MAXIMUM DREDGING DEPTH and SIDE SLOPES AND END TRANSITIONS, shall be deducted from the total amount dredged as excessive dredging for which payment will not be made. Nothing herein shall be construed to prevent payment for removal of shoals within the Dredge Prism performed in accordance with applicable provisions of either paragraph FINAL EXAMINATION AND ACCEPTANCE or paragraph

SHOALING.

Material dredged from beyond the Dredge Prism will result in the COR immediately reporting a water quality non-conformance/violation incident to WA Ecology. WA Ecology, WA Department of Natural Resources, and/or the US EPA may require Corrective Action, which shall be accomplished by the Contractor at the Contractor’s expense. Dredging shall be immediately discontinued until the cause of the excessive dredging is identified and corrected, and all Corrective Action is completed satisfactorily.

The Contractor shall specifically notify the COR, in writing, once the Contractor reaches approximately 75 percent of the quantities specified in the Contract Line Items. This notification shall be separate and in addition to other reporting required elsewhere in this Contract. This provision shall not be interpreted as an order for the Contractor to stop work upon reaching 75 percent of the estimated quantities. It merely requires notice and potential corrective action at that point. However, absent further specific direction, the Contractor shall be prepared to stop work on any CLIN at no additional cost to the Government once 100 percent of the line item quantity has been obtained and shall not resume dredging until a contract modification for additional quantity is awarded.

It is the Contractor’s responsibility to notify the Government as soon as the estimated quantities are identified to be insufficient to complete the work indicated and specified.

3.3.12 Quality Control

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

3.3.13 Surveys during Progress of Work

Quality of dredging depth will be determined by hydrographic surveys taken by the government per Section 1.11 SURVEY.

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3.3.14 Salvaged Material

Anchors, chains, firearms, and other articles of value, which are brought to the surface during dredging operations, must remain or become the property of the Contractor. All material must be removed from the work area as part of the construction process. No additional payment will be made for disposal of these items.

3.3.15 Safety of Structures

The prosecution of work shall ensure the stability of piers, bulkheads, and other structures lying on or adjacent to the site of the work, insofar as structures may be jeopardized by dredging operations. The contractor shall maintain a minimum standoff distance of twenty-five (25) feet from all piling structures and timber walls unless otherwise authorized by the COR. The Contractor shall repair at their own expense, damage resulting from disposal or dredging operations, insofar as such damage may be caused by variation in locations or depth of dredging, or both, from that indicated or permitted under the contract.

Dredging adjacent to a structure will not be permitted closer than that shown in the PLANS. Dredging adjacent to any structures or marine vessels shall require additional care to not cause damage to private or public property. Damage to private or public property or structures resulting from the disposal or dredging operations shall be repaired promptly by and at the Contractor's expense. Damage to structures as of a result of Contractor's negligence will result in suspension of dredging and require prompt repair at the Contractor's expense as a prerequisite to the resumption of dredging.

The Contractor is responsible for coordinating with the owner of the structure for any necessary repairs.

3.4 PLACEMENT OPERATIONS

3.4.1 Placement/Disposal of Dredged Materials

The deposit of dredged materials in unauthorized places is forbidden. Comply with rules and regulations of all federal, state, and local authorities. The material removed from the various dredging pay areas and dredging reaches shall be placed within the Government furnished material placement/disposal sites as described and shown on the contract PLANS.

Following placement of dredged material on the Parcel “O” and/or Jetty Island, no pits or depressions that could trap fish shall remain.

3.4.2 Placement in Indicated Site(s)

3.4.2.1 Placement/Disposal of Dredged Materials at Jetty Island

Material dredged from Sta. 65+00 to Sta. 78+00 shall be deposited on the west side of Jetty Island in a location as directed and as staked in the field by the Contracting Officer or COR. Pipeline dredged material shall be placed at specified elevations and sloped to allow proper drainage, as described in the PLANS. No material shall be placed outside the limits of the placement area. Any logs or stumps on the beach shall be stockpiled and placed on the beach above elevation +15.0 (MLLW) after completing the beach nourishment.

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All of the natural habitat features on the Jetty Island larger than 12 inches in diameter, including trees, stumps, logs and large rocks, shall be retained on the Jetty Island following construction. Natural materials may be moved if necessary, to allow access or placement of material in nearshore areas;

however, they should be replaced at similar elevations following construction.

Material placed shall not exceed the MAXIMUM PLACEMENT ALLOWANCE, 40,000 CY.

Sediments shall be discharged at the top of the existing beach in such a way as to allow the material to flow downslope to an intertidal substrate, where waves and currents will disperse material over time.

Construction debris and equipment shall be stored upland of mean higher high water (+8.5' MLL W) so that it cannot enter state waters or degrade water quality.

3.4.2.2 Placement/Disposal of Dredged Materials at Parcel O

The Contractor shall be responsible for inspecting and determining the condition of existing dikes Parcel “O” disposal area. Pre-bid site visits are recommended and should be coordinated through the Contracting Officer. The Contractor shall provide temporary dikes as necessary to contain disposed dredged material. Temporary diking or temporary stacking of material by the Contractor in conjunction with the disposal operations shall be required to achieve desired disposal volume and retention. The existing dredged material placed at this site during previous dredge events has been extensively re-handled by the City of Everett. Large quantities of the existing dredged material may continue to be removed by local entities from the site. The Contractor shall prepare and rework the placement site as required to re-slope the material in order to ensure suitable drainage of dredge effluent water. If any dike section is missing, undersized, or otherwise requires reworking or repairs in order to retain the dredged discharge material, including discharge water, the Contractor is responsible for repairing or replacing the dike sections at the Contractor’s expense.

The dredged material from Sta. 337+07 to Sta. 354+47 shall be placed in confinement dikes for the Parcel “O” disposal area. At the conclusion of the dredging, the Contractor shall be required to restore any existing breaches in the confinement dikes, such as those created for equipment access, or by other occasion, with on-site material if available, or obtain off-site material if necessary.

No anthropogenic debris associated with the dredged material is allowed to remain on Parcel “O” and on Jetty Island post-placement. Garbage, plastic, and any other anthropogenic debris encountered during construction shall immediately be removed, stored, and ultimately disposed in an appropriate designated upland facility. This includes debris pulled from the dredging area(s) as well as debris that makes it through the pipeline to Parcel “O” and Jetty Island. The WA Ecology is requiring that the contractor visually monitor for debris at active placement locations at a minimum of two times each day and record monitoring results.

Runoff shall be directed to the Snohomish River. Overflow shall be moderated using a suitably sized control structure (weir) that controls the rate and direction of flow, such that sediment is allowed to settle in the basin before overflowing into the river. The Contractor shall provide and maintain necessary bulkheads, dikes, ditches, weirs, spillways, and other construction necessary to confine and g3odwver Cross-Out

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retain the fill in the dredge fill area. The Contractor shall install and maintain a weir structure capable of maintaining at least one (1) foot of standing water within the settlement basin. The Contractor shall regularly monitor all outfall structures associated as part of the disposal activities. Any debris will be removed when observed, whether during planned monitoring or other activities on site, and the contractor shall identify a secure method for storing debris found on the Jetty Island. Prior to the commencement of dredging, the Contractor shall submit, as a section to their Work Plan, a Disposal Plan for approval by the Contracting Officer. The Disposal Plan shall include temporary pipeline access and routing and outfall location as required for the operation of Contractor’s plant and equipment. The Government will stake out the toe limits of the disposal sites.

The City of Everett advises that there are other users on their property therefore safe practices and coordination are required.

All debris collected during the dredging operations destined for disposal shall be disposed of by the Contractor, at the Contractor’s expense, at a facility authorized to receive the material.

Material placed shall not exceed the MAXIMUM PLACEMENT ALLOWANCE, 150,000 CY.

3.4.3 Misplaced Dredged Material

Any dredged materials deposited at locations other than in areas designated or approved by the COR will be considered misplaced material and will not be paid for until the Contractor, at his own expense, removes and deposits such misplaced material where directed. This required removal and redeposit of the misplaced material and any necessary placement site restoration work is not the basis for a time extension or additional compensation under this contract.

If the Contractor, during the progress of the work, loses, dumps, throws overboard, sinks, or misplaces any material, plant, machinery, or appliance, which in the opinion of the Government may be dangerous to or obstruct navigation or cause damage to the environment, the Contracting Officer will direct the Contractor to recover and remove the same with the utmost dispatch and at their own costs.

The Contractor shall give immediate notice, with description and location of such misplaced material, to the COR, and when required shall mark, buoy, or flag at the placement areas, such obstructions until the same are removed.

If the Contractor refuses, neglects, or delays compliance with the above requirements, such obstructions may be removed by the Government, and the cost of such removal may be deducted from any money due or to become due to the Contractor or may be recovered under the Contractor’s bond.

The liability of the Contractor for the removal of a vessel wrecked or sunk without fault or negligence shall be limited to that provided in Sections 15, 19 and 20 of the River and Harbor Act of March 3, 1899 (33 U.S.C. 410 et seq.).

Payment will not be made for any material that is placed elsewhere than in placement area shown or exceed the volume approved for the placement area, or as approved by the Government. The Contractor may be required to remove such misplaced material and deposit it in an acceptable area at no additional cost to the Government.

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Payment will not be made for any material relocated outside the construction area as shown in these plans and specifications.

3.4.4 Submerged/Floating Pipelines

If a leak occurs in the discharge pipeline, immediately discontinue using the line until leaks are repaired. Following a leak, the Contractor should conduct, or request the Government to conduct, a hydro survey to ensure that any dredged material discharged through the leak did not accumulate or cause mounding. If accumulation did occur, the Contractor must coordinate with the Government to remove the accumulated material, if deemed necessary. The Contractor is responsible for any resulting costs of repair and restoration.

3.4.4.1 Submerged Pipelines

The Contractor may elect to submerge sections of the dredge discharge pipeline for crossing a navigable channel.

The Contractor shall submit, as part of the Dredge Plan for approval, detailed plans of the submerged pipeline section(s).

Furnish and maintain navigation warning signs and warning lights along the pipeline (as applicable).

Submerged pipeline shall be marked in accordance with local USCG requirements and approved by the Government Designated Authority (GDA).

Unless otherwise specified by the USCG, submerged pipelines are considered to require special marks and shall have a USCG approved flashing yellow light.

Indicators, such as signs or buoys that state “DANGER SUBMERGED PIPELINE” shall be placed at the beginning and end of the pipeline.

If barges or other vessels are used to anchor the beginning and/or end of the submerged pipeline, they shall be lighted in accordance with 33 CFR 83.30.

Within a navigation channel, each end of the pipeline shall be identified with a regulatory marker buoy.

Lengths of submerged pipeline located outside of the navigation channel, shall be identified with high visibility buoys marked with 360-degree visibility retro-reflective tape, such as orange neoprene buoys, spaced at an interval not to exceed one hundred (100) feet apart.

3.4.4.2 Floating Pipeline

If the Contractor’s pipeline does not rest on the bottom, it shall be considered a floating pipeline and shall be visible on the surface and clearly marked. The Contractor's pipeline shall not be allowed to fluctuate between the surface or lie partly submerged. Lights shall be installed on the floating pipeline as required in the paragraphs LIGHTS and HYDRAULIC DREDGING LIGHTS, LIGHTED BUOYS AND DREDGING AIDS MARKERS. The lights shall be supported either by buoys or by temporary piling, provided by the Contractor and approved by the COR. Where the pipeline does not cross a navigable channel, the flashing yellow all-around lights shall be spaced not over 100 feet apart, unless closer

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spacing is required by U.S. Coast Guard personnel, in which case the requirements of the U.S. Coast Guard shall govern, at no additional cost to the Government.

3.5 DEFECTIVE/NON-CONFORMING WORK

Work that does not conform to the contract specifications and plans will be considered defective and non-conforming with these contract plans and specifications. Upon notice from the COR of defective or non-conforming work, the Contractor shall, within seven (7) calendar days, correct the defective work or provide a written plan to the COR describing the corrective action and schedule to perform the corrective action.

If the Contractor refuses or neglects…