Attachment V - 1806701Amend0003-SPC-APPENDIX I.pdf

APPENDIX ‘I’

Project Permits

REVISED APRIL 23, 2025

This page was intentionally left blank for duplex printing.

Commonwealth of Virginia

VIRGINIA DEPARTMENT OF ENVIRONMENTAL QUALITY

TIDEWATER REGIONAL OFFICE

5636 Southern Boulevard, Virginia Beach, Virginia 23462

(757) 518-2000 www.deq.virginia.gov Travis A. Voyles Michael S. Rolband, PE, PWD, PWS Emeritus Secretary of Natural and Historic Resources Director

(804) 698-4020

Craig R. Nicol

Regional Director

April 19, 2024

Captain Jip Mosman

United States Navy

Norfolk Naval Shipyard

Portsmouth, VA 23709

Transmitted electronically: nfsh_nnsy_pao@navy.mil

Re: Dry Dock 3 Modernization

Norfolk Naval Shipyard, Virginia

DEQ SWM #: 2024-0022

Erosion and Sediment Control Plan Approval

Dear Captain Mosman:

The Department of Environmental Quality (DEQ) has reviewed the Erosion and Sediment Control (ESC)

Plan (Plan) received March 27, 2024 in accordance with the Erosion and Sediment Control (ESC) Law & attendant Regulations. The Plan with latest revision date of March 25, 2024 and signed seal date of March

25, 2024 is hereby approved for 0.72 acres of land disturbance and a copy is enclosed. No changes may be made to the approved Plan without obtaining prior approval from DEQ.

Additionally, approval of the Plan does not relieve the operator of complying with all other federal, state, or local laws and regulations.

As provided by Rule 2A:2 of the Supreme Court of Virginia, you have thirty (30) days from the date you received this decision within which to appeal this decision by filing a notice of appeal in accordance with the Rules of the Supreme Court of Virginia with the Director, Virginia Department of Environmental

Quality.

It is the responsibility of the owner and/or operator to ensure that the project is constructed in accordance with the approved Plan and accompanying specifications.

http://www.deq.virginia.gov/ mailto:nfsh_nnsy_pao@navy.mil

Please contact swplanreviewers@deq.virginia.gov if you have any questions about this letter.

Respectfully, Noah Hill, VPDES Water Permits Manager

Tidewater Regional Office

Cc: Larry Gavan, DEQ-CO

Brad Ellis, Moffat-Nichol

Enclosure mailto:swplanreviewers@deq.virginia.gov wdm85536 Signature

COMMONWEALTH of VIRGINIA

DEPARTMENT OF ENVIRONMENTAL QUALITY

TIDEWATER REGIONAL OFFICE

5636 Southern Boulevard, Virginia Beach, Virginia 23462

(757) 518-2000 www.deq.virginia.gov Travis A. Voyles Michael S. Rolband, PE, PWD, PWS Emeritus

Secretary of Natural and Historic Resources Director

(804) 698-4020

Craig R. Nicol Regional Director

Captain Jip Mosman

United States Navy

Norfolk Naval Shipyard

Portsmouth, VA 23709

Transmitted electronically: nfsh_nnsy_pao@navy.mil

Re: Dry Dock 3 Modernization

Norfolk Naval Shipyard, Virginia

Stormwater Management Waiver Approval

Dear Captain Mosman:

The Department of Environmental Quality (DEQ) has reviewed the Request for Waiver of the requirement for an approved Stormwater Management (SWM) Plan received on April 18, 2024 in accordance with Guidance

Memo No. 15-2003, Postdevelopment Stormwater Management Implementation Guidance for Linear Utility

Projects under the Virginia Stormwater Management Program Regulation, 9VAC25-870. The Request for

Waiver of the requirement for an approved Stormwater Management (SWM) Plan dated March 25, 2024 with the most recent revision date of April 18, 2024 is hereby approved and a copy is enclosed.

This waiver applies only to the subject project and covers proposed land disturbance associated with the Dry

Dock 3 Repair and Modernization project at Norfolk Naval Shipyard. An ESC plan has been submitted for the remaining 0.72 acres of land disturbance. DEQ Approval of the ESC Plan will be processed separately from this waiver approval. Please be sure to include a copy of this approval with your records.

As provided by Rule 2A:2 of the Supreme Court of Virginia, you have thirty (30) days from the date you received this decision within which to appeal this decision by filing a notice of appeal in accordance with the

Rules of the Supreme Court of Virginia with the Director, Virginia Department of Environmental Quality.

Prior to the commencement of construction, all land-disturbing activities equal to or greater than one acre, or less than one acre and part of a larger common plan of development or sale, must register for coverage under mailto:nfsh_nnsy_pao@navy.mil

DEQ SWM#: 2024-0022

the General VPDES Permit for Discharges of Stormwater from Construction Activities (VAR10). If not already submitted, a copy of the 2014 General Permit registration statement can be obtained from DEQ’s website at the following location:

http://www.deq.virginia.gov/Portals/0/DEQ/Water/Publications/CGPRegistrationStatement2014.pdf

Please contact the SWM Plan Review team at PlanReview@deq.virginia.gov if you have any questions about this letter.

Sincerely, April Rhodes, OSWM Plan Review Manager

DEQ Central Office

Cc: Larry Gavan, DEQ-CO

Noah Hill, VPDES Water Permits Manager

Brad Ellis, Moffat-Nichol http://www.deq.virginia.gov/Portals/0/DEQ/Water/Publications/CGPRegistrationStatement2014.pdf mailto:PlanReview@deq.virginia.gov

NMFS EFH Consultation Dry Dock 3 Modernization Norfolk Naval Shipyard, Portsmouth, August 2024

PRM401

August 299, 2024

Mr. Lou Chiarella NOAA Fisheries Service National Oceanic and Atmospheric Administration 55 Great Republic Drive Gloucester, MA 01930-2276

RE: REQUEST FOR ESSENTIAL FISH HABITAT CONSULTATION: NORFOLK NAVAL

SHIPYARD DRY DOCK 3 REPAIR AND MODERNIZATION

Dear Mr. Chiarella:

The U.S. Navy is proposing to complete repairs and modernization activities at the Norfolk Naval Shipyard (NNSY) Dry Dock 3 (DD3) within the southern branch of the Elizabeth River, Portsmouth, Virginia (Figure 1). DD3 is located on the western shoreline of the river between Dry Dock 2 and Dry Dock 4 (Figure 2). The specific area of this proposed action is at the entrance to DD3. DD3 was constructed in 1908 and is currently used to service submarines. The last major structural renovations to the dry dock were completed in the mid-1960s. To ensure DD3 can maintain its operational certification, the critical upgrades described in this proposed action are required.

This letter serves as the Navy’s request to initiate essential fish habitat (EFH) consultation under the Magnuson-Stevens Fishery Conservation and Management Act regarding the proposed project for any potential effects on EFH within National Marine Fisheries Service’s (NMFS) jurisdiction.

As described below, the Navy has determined that while the proposed project may adversely affect EFH, those adverse effects would not be substantial. Our supporting analysis is provided below.

DEPARTMENT OF THE

NAVY

N O R F O LK N AV AL S H I P Y AR D

Norfolk Naval Shipyard, Portsmouth, August 2024

Figure 1. Project Location

Figure 2. Proposed Construction at DD3

Norfolk Naval Shipyard, Portsmouth, August 2024

1. PROPOSED PROJECT

The facilities and equipment at DD3 require modernization to continue servicing Naval vessels, including the newest classes of submarines, as well as to ensure that infrastructure at the dock can support projected future sea level rise/uplift.

DD3 was built in 1908 and last underwent major structural renovations in the mid-1960s. The components of the DD3 modernization include: anchoring of the drydock floor, reconstruction of the dry dock entrance, replacement of the abandoned dry dock pumpwell with a new wet well system, reinforcement and resurfacing of the dry dock floors and walls, and replacement of all utility systems. The improvements being proposed at DD3 will mitigate risks associated with sea level rise/uplift and provide updated infrastructure to support the newest classes of submarines.

The in-water components of the repair and modernization work include installation of a cofferdam, dredging, and repairs and upgrades to intakes and outfalls within the project limits. Project drawings are included with this letter as Attachment A.

The operational certification of DD3 is scheduled to expire soon and without major repairs, the dry dock will not be recertified. This project will ensure docking of Navy ships and precludes impacts to fleet schedules and ship operational availability. Without these improvements, NNSY will not be able to support the dry docking of the existing and projected U.S. submarine fleet, as there are inadequate drydocks both public and private to support this need. Consequently, Navy readiness would be greatly reduced without the proposed modernization.

1.1. In-Water Construction Activities

The in-water activities are expected to occur during an initial 5-month period to complete cofferdam installation and dredging. Dredging would then occur behind the maintained cofferdam and prior to dewatering the cofferdam. Once the dock is dewatered, construction activities would then occur in the dry behind the maintained cofferdam for approximately 4 years, followed by an approximate 5-week period for in-water cofferdam removal at the dry dock entrance. Table 1 describes the proposed in-water activities, duration, and anticipated impact area and type and Figures 3 and 4 show the plan view and cross-section design for the in-water work at DD3. Work that will occur within the dry dock (in the dry) is not included in the table below. Detailed construction methods and Best Management Practices (BMPs) for each activity are described in sections below.

To minimize impacts to water quality during in-water activities (dredging and cofferdam installation) and provide maximum water quality protection, the installation of a turbidity curtain around the in-water activity area is proposed.

Norfolk Naval Shipyard, Portsmouth, August 2024

Table 1. In-water construction sequence and duration timelines for DD3

In-water Activity Description Anticipated Timeline

Impact Type/Duration/Size

Install turbidity curtain

Install Type III turbidity curtain and oil-absorbent boom across entrance of

DD3

1 day Best management practice/temporary/180 linear feet (LF)

Install cofferdam piling

Install cofferdam pipe pile and sheet piling across DD3 entrance; use interlocked 60-inch diameter steel pipe piles with 20-inch steel sheet pile tie-ins for the closure walls

3 months Structure installation/Permanent/~180 LF

Dredging Within dry dock entrance cofferdam limits, mechanical and/or hydraulic suction dredging of approximately 1,750 cubic yards of material to facilitate construction of the cofferdam tremie slab and closure walls

1 month - inside cofferdam

Excavation/Permanent/1,650 square feet (SF)

Construct tremie concrete seal slab and closure walls

Within dry dock entrance cofferdam limits, install tremie concrete seal slab and closure walls

1 month- Inside cofferdam, following dredging

Structure installation/Permanent

Turbidity curtain removal

Remove turbidity curtain and oil-absorbent boom at entrance of DD3 following completion of cofferdam construction

1 day Best management practice/temporary/180 LF

Norfolk Naval Shipyard, Portsmouth, August 2024

In-water Activity Description Anticipated Timeline

Impact Type/Duration/Size

Turbidity curtain installation

Install Type III turbidity curtain and oil-absorbent boom across entrance of DD3 prior to cofferdam removal

1 day Best management practice/temporary/180 LF

Remove cofferdam components

Demolish concrete closure walls.

Cut cofferdam piling at mudline

4 weeks Structure removal/Permanent/

180 LF/580 SF

Turbidity curtain removal

Remove turbidity curtain and absorbent oil boom at entrance of DD3 following removal of cofferdam components

1 day Best management practice/temporary/180 LF

Figure 3. DD3 Plan View for In-water Activities

Figure 4. DD3 Cofferdam Cross-Section

The proposed project will include the following in-water activities. No concurrent in-water activities are proposed.

Norfolk Naval Shipyard, Portsmouth, August 2024

1.1.1. Installation of Turbidity Curtain and Absorbent Boom

A turbidity curtain and oil-absorbent boom will be placed across the entrance of DD3 before in water work begins. The oil-absorbent boom will be installed on the protected side of the turbidity curtain. The curtain and boom would be removed following completion of the cofferdam, reinstalled before the cofferdam is removed (cut at the mudline), and then removed again following removal of the cofferdam components. The curtain will be weighted at the bottom and anchored to the existing, adjacent berth structures to minimize sediment transport. The turbidity curtain used will be Type III and will be in conformance with the floating turbidity curtain specification from the 1992 Virginia Department of Environmental Quality Sediment and Erosion Control Handbook.

An absorbent boom will be deployed on the interior side of the turbidity curtain to absorb any oils or fuels. Dredging will occur completely behind the cofferdam. Turbidity monitoring to assess effectiveness of the curtain will be conducted in accordance with an approved Water Quality Monitoring Plan.

1.1.2. Installation of Cofferdam Sheets and Piles

New construction includes pile driving for cofferdam pipe piles and sheet piles (Table 2). All cofferdam pile driving (and associated activities) will take place within the turbidity curtain. Prior to installation, the cofferdam alignment will be probed for near-surface obstructions using a steel 14-inch H-pile. Probe piles will be installed and then immediately extracted using a vibratory hammer. If obstructions are encountered along the alignment, they will be removed using a clamshell bucket or grapple. A cofferdam consisting of steel pipe piles and sheet piles will be installed across the DD3 entrance, approximately 180 linear feet. The sediment within the interior of the pipe piles (after installation) will be removed via pump system and managed in accordance with the project’s approved Dredged Material Management Plan. Cofferdam piles to be driven include 60-inch-diameter steel pipe piles that will be initially driven with vibratory hammers and then driven to final specifications with an impact hammer. Additionally, 20-inch flat steel sheet piles will also be installed using a vibratory hammer. A template supported by smaller diameter steel pipe piles (assumed 18-inch diameter) will be installed to maintain alignment of the cofferdam piling during initial cofferdam pile placement. Template piles will be installed and extracted using a vibratory hammer. Following installation of the cofferdam piling, dredging will be performed inside the cofferdam for placement of a tremie concrete seal slab and to remove accumulated sediment from atop the existing concrete apron located between the proposed tremie slab and the dry dock entrance seat. The tremie seal slab is part of the cofferdam system and is designed to cut off seepage of river water beneath the cofferdam piling into the area between the cofferdam piling and the dry dock structure. It also acts as a structural brace between the cofferdam piling and the dry dock structure. The thickness of the slab is designed to resist hydrostatic uplift resulting from the differential water levels inside and outside of the cofferdam. The top of the tremie slab is set slightly below the authorized dredge depth of the DD3 approach channel and therefore will not impact navigational access to the dry dock or change riverbed elevation.

Dredging and construction of the tremie concrete seal slab will be performed on the protected side of the cofferdam. Following placement of the concrete seal slab, formwork will be placed inside the cofferdam and tremie concrete poured to complete construction of the sheet pile cofferdam closure walls. After dredging and construction of the seal slab and closure walls is complete, the

Norfolk Naval Shipyard, Portsmouth, August 2024 area behind the cofferdam will be dewatered using either temporary pumps or the existing Dry Dock 2 pumpwell system. Dewatering and discharge will be addressed in an agency approved Water Management Plan that will be developed by the construction contractor and the point source discharge will likely be covered using Virgnia Pollutant Discharge Elimination System (VPDES) General Permit (GP) VAG-83. Following completion of all rehabilitation/modernization work at DD3, the cofferdam closure walls will be demolished, the cofferdam piling will be cut at the mudline and the concrete tremie slab will be abandoned in place, resulting in 1,650 square feet of material (fill) remaining in the sediment. Abandonment in place of these components will eliminate resuspension of sediment that would occur during extraction.

1.1.3. Dredging

No dredging associated with this project is navigationally related, although dredging is required prior to constructing the concrete tremie slab behind the cofferdam in order for the tremie slab to align with the existing floor of the drydock, and will be performed prior to the dewatering of the cofferdam. Once constructed, the concrete tremie slab will reduce seepage into the dewatered cofferdam and act as a structural brace between the cofferdam piling and existing DD3 concrete apron. Mechanical and/or hydraulic suction dredging will be performed on the protected side of the cofferdam to remove approximately 1,750 cubic yards of material. Material will be dredged to a depth of -46 feet mean lower low water (MLLW) across the proposed concrete tremie slab footprint. The dredging area for the concrete tremie slab is approximately 1,650 square feet.

Dredging may be conducted using a combination of mechanical and hydraulic suction methods, dependent upon the contractor’s means and methods. Mechanically dredged material will be dredged with a clamshell dredge bucket and deposited directly into a hopper barge located within the turbidity curtain and absorbent boom. Spill shields will be used to prevent incidental release of sediment and water from entry into surface water as the bucket swings to the hopper barge and back. The amount of material removed from DD3 will require only a single barge for loading and transport to the material destination. Management of decant water from the barge will be described in the contractor’s approved Water Management Plan. Options may include pumping the decant water to an onsite frac tank for subsequent treatment and discharged under VPDES GP VAG-83.

Alternatively, the contractor could choose to transport the decant water to an off-site location (by land) for treatment and disposal via truck or barge. If transported via barge, adequate freeboard will be maintained, and no overflow will be permitted. Removing the decant water from the hopper barge will minimize the potential for incidental release during transport and material offloading at the disposal site and will accelerate the material drying process. As stated above, the dredged material will be transported off-site via the hopper barge and managed and amended (if necessary, to facilitate further drying) at a permitted facility. The treated material will then be transported for final disposition at a permitted landfill

Given the irregularly shaped and confined area to be dredged, some amount of hydraulic suction dredging will likely be required. Hydraulic suction dredging will be performed using a cable-deployed dredge pump, diver-operated dredge pumps, or similar hydraulic dredging equipment designed for use in confined areas. The dredged material will be pumped (slurry) from the suction intake to a geotube for containment and dewatering. Geotubes are tubular, bag-like dewatering containers constructed from a specially engineered textile that allows for water to be removed from the dredged material (dewatering) followed by consolidation of the solid material remaining in the

Norfolk Naval Shipyard, Portsmouth, August 2024 tube after dewatering is complete. Geotubes will be temporarily positioned in a lined, upland containment area adjacent to DD3. Dredged material from DD3 will be pumped directly into each geotube. After the geotubes are filled with dredged material, the water will drain through small holes in the geotube fabric and be collected in a filtrate pond. Management of the water generated as part of the hydraulic dredging operation (i.e., dewatered through the geotubes) will be described in the contractor’s approved Water Management Plan. Water may be treated using a treatment system to be designed based on the contaminants of where the discharge to surface waters would be covered by VPDES GP VAG-83 or the contractor may choose to transport the water off-site for treatment and disposal. Upon completion of dredging and geotube dewatering, the geotubes containing the consolidated dredged material will be transported off-site via sealed dump trucks or roll-off containers and managed and amended (if needed) at a permitted facility. The treated material will then be transported at a permitted landfill (if required).

1.2. Dredged Material Testing Results and Placement

Sediments within the proposed dredging area and cofferdam installation footprint were sampled to a depth of 15 feet below sediment surface in March 2024. Bulk sediment and elutriate testing were performed for 5-foot depth intervals and whole core composites. Analytical testing included polycyclic aromatic hydrocarbons (PAHs), metals/mercury, polychlorinated biphenyl (PCB) congeners, chlorinated pesticides, cyanide, total petroleum hydrocarbons, oil & grease, total organic carbon, grain size, and total solids. In addition, waste characterization testing was conducted to facilitate off-site placement/disposal.

Results of the sediment characterization indicated that concentrations of metals, PAHs, and total PCBs exceeded effects range-median values, and total petroleum hydrocarbons and oil & grease were present in sediments in the cofferdam installation and dredging area. In addition, dissolved concentrations of PCBs, PAHs, and chlorinated pesticides were detected in the 100 percent elutriate samples at concentrations exceeding Commonwealth of Virginia water quality criteria for the protection of aquatic life and Commonwealth of Virginia human health criteria for other surface waters. Results of sediment sampling for the purposes of waste characterization indicate the sediment is non-hazardous and may be managed at upland permitted facilities upon acceptance.

The dredged material will be placed upland at a permitted facility. The exact placement location for the material will be selected by the construction contractor. Possible disposal locations include Dominion Recycling Center in Chesapeake, Virginia, and Port Tobacco at Weanack (also known as Shirley Plantation) on the James River. Material acceptance letters have been received from both facilities.

In both scenarios, it is anticipated that the volume of dredged material will only require one barge for transport to a landside offloading location. Placement of the material at the Dominion Recycling Center would require barge transit upstream from the project site to an offloading area adjacent to the facility in Chesapeake, a total one-way transit of approximately 6.5 statute miles.

At the offloading facility the material would be mechanically placed in trucks and moved to a specified location/cell at the facility for drying and final disposition. Placement of the material at Shirley Plantation would require barge transit northward from the Southern Branch of the Elizabeth River to the Elizabeth River and upstream into the James River to Port Weanack, a total one-way transit route of approximately 65 statute miles. Once the barge reaches the Port Weanack

Norfolk Naval Shipyard, Portsmouth, August 2024 facility, dredged material would be mechanically offloaded. The dredged material would be offloaded to trucks and temporarily placed in clay-lined pits for drying at Port Weanack. Once the dredged material has been sufficiently dried to meet geotechnical requirements for landfill disposal, the dredged material will be trucked to Charles City Landfill (or an alternate permitted local landfill). Port Weanack is fully permitted to support pre-treatment activities (if needed) and has successfully performed similar drying and pretreating operations for other dredging projects with similar contaminants. Handling, transport, and drying of material by the selected contractor will be detailed in an approved Dredged Material Management Plan.

1.3. Other Construction/Repair Activities

Several activities will also occur in the dry during the DD3 modernization, which includes new construction and upgrades to intakes and outfalls that are used to facilitate routine operations of the drydock (e.g., withdrawal and/or discharge from/to the river). The existing, replacement, and new structures are each located near the DD3 entrance (Figure 5 and Drawing No S-214P). The upgrade of these features will be performed in the dry behind the cofferdam. Each activity is described below.

Figure 5. Location of Intake and Outfall Structures Proposed for DD3

1.3.1 DD3 Drainage Pump Discharge (new construction)

Current operations at DD3 primarily rely on the pumpwell system at Dry Dock 2 for drainage (dewatering) of the dry dock. Currently, the DD3 has two existing dry dock dewatering pumps (15,500 gallons per minute [gpm] combined capacity) and their associated 20-inch outfall pipe, which will be demolished as part of the project.

The proposed action constructs a new DD3 wet well structure with drainage pumps to dewater DD3 during drydocking evolutions (complete drainage of the dock area). Drydock evolutions occur only twice every 2 years on average. The new dewatering pump system will consist of six vertical drainage pumps that pull water at a rate of 21,500 gpm per pump and two 48-inch iron

Norfolk Naval Shipyard, Portsmouth, August 2024 outfall pipes with flap gates. The two outfall pipes with iron flap gates will be constructed at approximately -7.8 feet and -15.8 feet MLLW. Once construction is complete and under normal operating conditions, to dewater DD3, a steel caisson structure will be floated across the entrance to seal off the dry dock from the river. Water from DD3 will be pumped through the new wet well structure (approximately 20 million gallons) and discharged to the river over an approximately 3-hour period. Over the pumping period, rubber seals affixed to the steel caisson structure are compressed against the concrete dry dock seat, forming a watertight seal against the dry dock. The combination of river water ballast inside of the caisson ballast tanks and differential water pressure acting on the riverside of the caisson hold the caisson in place.

There will be no change in total volume of dewatering discharge to the river between the two dry dock drainage pump systems.

1.3.2 DD3 Environmental Process Pump Discharge (replacement of existing structure)

Two existing dry dock drainage pumps (1,800 gpm combined), two existing sump pumps (200 gpm combined), and their associated 10-inch outfall pipe at the existing DD3 pumpwell will be demolished as part of the project. The existing pumps will be replaced with four new environmental process pumps in the new DD3 wet well that will discharge collected water (e.g., rain, seepage) from the dock area, when the dock is empty, to the river at a maximum rate of 750 gpm per pump; however, based on the design discharge flow rate a maximum of three pumps would be in operation at one time; the fourth pump would be used as a backup should one fail.

These three pumps operating would be expected to have a variable discharge rate between 1,000 and 2,250 gpm. A new 10-inch iron outfall pipe that reduces to an 8-inch diffuser will be constructed at approximately -26.3 feet MLLW to receive those variable discharge rates (between 1,000 and 2,250 gpm) from the new process pumps installed in the DD3 wet well.

1.3.3 DD3 Superflood Intake (upgrade/replacement of existing structure)

A new intake for the purpose of superflooding DD3 would be constructed as part of the modernization activities. A single 48-inch iron intake pipe with screen (openings sized 6 inches by 6 inches) would be constructed at approximately -23.8 feet MLLW to be used in conjunction with three of the vertical drainage pumps to superflood DD3 when necessary. Intake velocity for the new intake would remain as the current DD2 velocity of 10.42 feet per second. Superflooding involves pumping river water (at a rate of 60,000 gpm) into the dry dock basin to raise the water level within the basin, above the adjacent river level while the dry dock caisson is in place.

Superflooding is only performed when the water level within the dry dock basin is too low to allow the vessel being docked or undocked to be moved safely over the keel blocks within the dry dock.

Typically, superflooding is only required if a damaged vessel drafting more water needs to be docked or when a docking evolution occurs during a low tide period.

As such, it is anticipated that superflooding will not be necessary more than once every 2 years.

Construction of the new DD3 wet well system will shift the superflood intake for DD3 from the existing DD2 pumpwell system to the new DD3 system. There will be no change in total river water withdrawal between the two dry dock superflood intake systems.

Norfolk Naval Shipyard, Portsmouth, August 2024

1.3.4 DD3 Auxiliary Salt Water (ASW) Discharge (upgrade of existing structure)

In current DD3 operations, water is drawn from the river at existing NNSY pumpstations and supplied to DD3 through underground saltwater distribution system piping. Saltwater is then supplied to vessels in DD3 via hose connections to shipboard piping to provide component cooling.

Cooling water is not currently discharged directly to the river; instead the water is routed from the vessel to the auxiliary salt water (ASW) piping to the DD2 pumpwell system and then discharged to the river using either the DD2 sump pump or drainage pumps. The proposed action involves constructing a new 6-inch iron outfall pipe at -16.3 feet MLLW to allow discharge directly to the river. The expected discharge rate will be approximately 950 gpm from the dock to the river, continuously when there is a vessel in the dry dock and discharge temperatures have been modeled at 95°F. The distance to the ≤3°C water quality criterion was met within 24.1 feet in the summer and 35.1 feet in the winter, well within the 195-foot regulatory mixing zone.

Both the existing discharge and proposed discharge are compliant with VAC 25-260-20 and NNSY Virginia Pollutant Discharge Elimination System (VPDES) Permit Number VA0005215.

While the project proposes to construct a new dedicated ASW outfall, the total volume to the river will not change.

1.3.5 Storm Drain Outfall (new construction)

A new 18-inch-diameter stormwater outfall will be constructed on the north side of the dry dock entrance (at -1.7 ft MLLW) to replace an existing 12-inch-diameter stormwater outfall. The peak stormwater flow to the outfall is 4.45 cubic feet per second (1,998 gpm) for the 1-year, 24-hour duration storm event. The peak stormwater flow to the outfall is 8.04 CFS (3,609 gpm) for the 10-year, 24-hour duration storm event.

1.4. Anticipated Schedule

The anticipated construction award date for the project is March 2026 with an estimated project construction duration of approximately 4.5 years. The initial in-water work is limited to approximately 4 months to install the cofferdam and perform dredging. The duration of work behind the cofferdam is expected to be approximately 4 years. Following completion of construction behind the cofferdam, approximately 5 weeks of in-water work will be performed to cut off the cofferdam piling and remove the closure walls.

Norfolk Naval Shipyard, Portsmouth, August 2024

Table 1: Pile Installation and Removal

Average Water Depth at Project Site

Method of Pile Driving

Extract/Install Number of Piles or Sheet Piles

Material (timber, concrete, sheet, etc.)

Size of Piles

Impact driving strikes per pile

Minutes to drive / extract each pile (includes sheet piles)

Max.

number of piles installed / extracted each day (includes sheet piles)

Total number of days of pile driving / extraction required (includes sheet piles)

-33 (feet, MLLW)

Vibratory Hammer

Probe Piles Install and Immediately Extract

60 Steel H-Piles 14-inch HP -N/A- 30 minutes/ location

12/day 5 days

-33 (feet, MLLW)

Vibratory Hammer

Install Template Piles 30 Steel Pipe Piles 18-inch Diameter

-N/A- 20 minutes/ each

8/day 4 days

-33 (feet, MLLW)

Vibratory Hammer

Extract Template Piles

30 Steel Pipe Piles 18-inch Diameter

-N/A- 20 minutes/ each

8/day 4 days

-33 (feet, MLLW)

Vibrate and Impact

Install Cofferdam Piles

27 Steel Pipe 60-inch Diameter

700 blows 60 minutes Vibrate, 60 minutes Impact

2/day 30 days

-33 (feet, MLLW)

Vibratory Hammer

Install Cofferdam Piles

20 PS31 Flat Steel Sheet Piles

20 inches wide

-N/A- 30 minutes/ each

6/day 4 days

Norfolk Naval Shipyard, Portsmouth, August 2024

2. DESCRIPTION OF THE ACTION AREA

The action area is defined as “all areas to be affected directly or indirectly by the Federal action and not merely the immediate area involved in the action” (50 Code of Federal Regulations §402.02).

The immediate action area for this project includes the Southern Branch of the Elizabeth River, including: those areas of the river within and immediately adjacent to DD3 where work will be focused (shown in Error! Reference source not found.); the underwater areas where the most concentrated consequences of the action could be experienced (e.g., noise from pile extraction/installation, increases in turbidity, and a concentrated increase in vessel traffic); and any in-water transit route from DD3 to a selected disposal location.

Additionally, the action area includes the potential vessel transit routes for construction vessels and vessels used to dispose of dredged sediments. While the exact transit routes for vessels coming into and out of the project area and for those used for upland placement of the dredged material would be identified by the construction contractor (see Section 1.3), the defined action area for the project and associated EFH assessment includes an analysis of the material being transported via barge to Port Weanack (Figure 6). The Navy believes this location represents the farthest transport distance from the DD3 area. Material could also be barged to the Dominion Recycling Center location; however, it is closer to the project site and transit to this location would have less potential for impacts to listed species and no effects to critical habitat.

Figure 6. Vessel Transit Route to Port Weanack

Norfolk Naval Shipyard, Portsmouth, August 2024

The Elizabeth River is a tidal tributary of the Chesapeake Bay in Virginia. More than three-quarters of the Chesapeake Bay’s tidal waters are considered partially or fully impaired by chemical contaminants. Common organic chemical contaminants in the Chesapeake Bay include PCBs, PAHs, and pesticides. Data indicate the extent of PCB contamination in the watershed is widespread. PAHs are detected at varying concentrations across the watershed, with the highest reported in or near Baltimore Harbor and the Anacostia and Elizabeth Rivers (Chesapeake Bay Program, 2023a).

Land use along the Southern Branch of the Elizabeth River is primarily industrial and military with facilities located along the river that support shipping, waterborne commerce, and defense. There are several shipyards, which repair both private and military vessels, with the NNSY being one of the largest. Many areas are comprised of deep-water commercial/industrial berths and bulkheads and most of this reach of the river is dredged and maintained for large vessel access.

The Southern Branch of the Elizabeth River is 14.5 miles (23.3 kilometers) long and flows from south to north. The width of the river in the vicinity of Dry Dock 3 is approximately 1,200 feet (370 meters). The navigation channel extending from Lamberts Bend to the NNSY is maintained to -47 feet (-14.3 meters) MLLW. The Elizabeth River’s tidal range extends south to the Great Bridge Locks, in Chesapeake, Virginia, which controls inflow to the river. The Southern Branch of the Elizabeth River is subject to daily tides, with the typical tidal range approximately 2.85 feet (0.87 meter), although this varies significantly based on the time of the month (spring and neap tides) and storm activity, which can create significant storm surges well beyond the normal tidal range (U.S. Army Corps of Engineers [USACE] 2018). According to a 2017 USACE report, “Because the Elizabeth River has topographically low relief, a relatively small drainage area, and large areas of urban land use, groundwater flow into the river is minimal and there are substantial peak freshwater inflows during rainy periods. Thus, the freshwater input from the tributaries is low during dry periods and has high peaks during wet periods.” (USACE 2017).

The benthic community in the Elizabeth River system is low in biomass and diversity due to low dissolved oxygen, toxic contaminants, and sediment composition (e.g., clays, silt and fines with no reef or hard bottom habitat either in the channel or on the side slopes) (USACE 2017). The organisms which colonize this type of benthic habitat are typically a limited suite of small, opportunistic species with a short life cycle, and are adapted to soft bottom environments with frequent disturbance that precludes establishment of long-lived components. Such areas tend to recover to these previously described conditions quickly from disturbances, ranging from approximately 6 to 8 months to 2 years (Newell et al., 1998).

The heavily industrialized Southern Branch of the Elizabeth River is the most heavily polluted section of the river. The U.S. Environmental Protection Agency (EPA) lists the Southern Branch of the Elizabeth River as impaired for aquatic life, fish and shellfish consumption, swimming, and boating due to PCBs, bacteria and other microbes, dioxins, low dissolved oxygen, and degraded aquatic life (EPA 2022). The Southern Branch is also where the Elizabeth River Project has organized its largest cleanup efforts, with multiple partners. Excess nitrogen is one of the top causes of dead zones throughout the Chesapeake Bay. Although the Elizabeth River traditionally has been one of the Bay’s most degraded tributaries, nitrogen levels are dropping steadily not only in the Elizabeth River Southern Branch, but also the Western Branch, Eastern Branch and Main Stem. As of 2014, the Southern Branch showed improving trends for bacteria and bottom health, Norfolk Naval Shipyard, Portsmouth, August 2024 including contamination and nitrogen. Of concern, however, are poor scores reflecting high levels of PCB contamination in fish and crabs in much of the river. Although in general, edible fish have lower concentrations of PCBs than non-edible fish, the Virginia Department of Health has issued fish consumption advisories for the lower James and Elizabeth Rivers based on PCB levels in fish.

PCB contamination is a complicated problem to address since the compound persists in the environment and moves through the food chain. Within the Southern Branch, while contamination on the river bottom has been cleaned up or improvement efforts are underway at key sites, including Money Point and Atlantic Wood, more contaminated sites remain. According to the River Grade map issued by the Elizabeth River Project, the Southern Branch of the Elizabeth River has improved from a D (in 2014-2018) to a C (in 2015-2019) but is still at D for bacteria and F for benthic invertebrates and PAHs in sediment (Elizabeth River Project 2021 and 2023).

Water quality data from 2018 to 2023 for the Southern Branch of the Elizabeth River shows an average dissolved oxygen level of 6.9 milligrams per liter (mg/L), average salinity of 18.2 parts per thousand, average temperature of 17.1 degrees Celsius (oC) (62.7 degrees Fahrenheit [oF]), average pH of 7.4, and average turbidity of 3.3 nephelometric turbidity units (Chesapeake Bay Program 2023b; Chesapeake Bay National Estuarine Research Reserve in Virginia, Virginia Institute of Marine Science [VIMS] 2023; Virginia Department of Conservation and Recreation 2023).

The shorelines of the Southern Branch of the Elizabeth River have been heavily modified because it is a maintained navigation channel, with minimal areas of intertidal shallows along the shorelines. Most of the shoreline within the Southern Branch of the Elizabeth River consists of hardened shoreline associated with the berths and docks along the edges of the shipyard and other industrial developments. The river depths are approximately 46 feet (14 meters) to more than 48 feet (15 meters) deep in the channel of the river and 30 feet (9 meters) to 47 feet (14 meters) deep in the immediate vicinity of DD3, according to bathymetric condition surveys conducted by the Navy in November 2021. The substrate within the Southern Branch of the Elizabeth River is soft, consisting primarily of fine silts and clays, with a small portion of fine sands, gravel, and shell. No submerged aquatic vegetation (SAV) or shellfish beds are present within the Southern Branch of the Elizabeth River, according to the VIMS Interactive SAV Map. SAV beds are shown along the upper reaches of the edges of the James River at and below Port Weanack and along the northern edge of the mouth of the James River at Hampton Roads (VIMS 2023).

The James River is the longest river (340 miles) in Virginia flowing from the Appalachian Mountains to Hampton Roads and has a 10,000 sq mile watershed. The lower James River and watershed area covers the portion of the river (and surrounding land and tributaries) from Richmond to the river’s confluence with the Chesapeake Bay (James River Association 2024).

Port Weanack is located within this segment of the James River. The James River bottom is comprised largely of silty-clay material, with a high portion of coarse-grained material toward the mouth of the river (Nichols 1972). Throughout its length the river supports critical habitat for Atlantic sturgeon, along with a variety of marsh habitats (James River Association 2024).

Norfolk Naval Shipyard, Portsmouth, August 2024

3. LIST OF FEDERALLY MANAGED SPECIES WITH EFH AND HABITAT AREAS

OF PARTICULAR CONCERN

To determine a list of federally managed species with EFH, a review of the NOAA EFH Mapper (NMFS n.d.) was conducted. This resulted in identification of 11 species with EFH in the action area (Table 3).

Table 3: Summary of Essential Fish Habitat Designations for the Proposed Action Area

Common Name Scientific Name Life Stage(s) Present

Management Council

FMP

Atlantic Butterfish Peprilus triancanthus Adult Juvenile

Mid-Atlantic Atlantic Mackerel, Squid, & Butterfish Amendment

Atlantic Herring Clupea harengus Adult Juvenile

New England Amendment 3 to the Atlantic Herring Fishery Management Plan (FMP)

Black Sea Bass Centropristis striata Adult Juvenile

Mid-Atlantic Summer Flounder, Scup, Black Sea Bass

Bluefish Pomatomus saltatrix Adult Juvenile

Mid-Atlantic Bluefish

Clearnose Skate Raja eglanteria Adult Juvenile

New England Amendment 2 to the Northeast Skate Complex

FMP

Little Skate Leucoraja erinacea Adult New England Amendment 2 to the Northeast Skate Complex

FMP

Red Hake Urophycis chuss Adult Juvenile Larvae Eggs

New England Amendment 14 to the Northeast Multispecies

FMP

Sand Tiger Shark Carcharias taurus Adult Juvenile Neonate

Secretarial Amendment 10 to the 2006 Consolidated HMS FMP:

EFH

Sandbar Shark Carcharhinus plumbeus

Juvenile Neonate

Secretarial Amendment 10 to the 2006 Consolidated HMS FMP:

EFH

Summer Flounder Paralicthys dentatus Adult Juvenile Larvae

Mid-Atlantic Summer Flounder, Scup, Black Sea Bass

Windowpane Flounder

Scophthalmus aquosus Juvenile New England Amendment 14 to the Northeast Multispecies

FMP

Note:

NMFS. n.d. Essential Fish Habitat (EFH) Mapper (New England/Mid-Atlantic).

https://www.habitat.noaa.gov/apps/efhmapper/efhreport/. Accessed on 10 April 2024.

Norfolk Naval Shipyard, Portsmouth, August 2024

Habitat areas of particular concern (HAPC) are subsets of EFH and are habitat types and/or geographic areas identified as priorities for habitat conservation, management, and research. They either play important roles in the life history (e.g., spawning areas) of federally managed fish species or are especially vulnerable to degradation from fishing or other human activities. In many cases, HAPCs represent areas where detailed information is available on the structure and function within the larger EFH.

As shown in Table 4, HAPCs are identified within the action area for sandbar shark (Secretarial Management Council) and summer flounder (Mid-Atlantic Management Council).

Table 4: Summary of HAPC Designations for the Proposed Action Area

HAPC Name Management Council Description Sandbar Shark NMFS Highly Migratory

Species (HMS) Division Currently, only three HAPCs for sandbar sharks have been identified, including: three separate areas off of North Carolina; Chesapeake Bay, Maryland;

and Great Bay, New Jersey.

Summer Flounder

SAV

Mid-Atlantic Fishery Management Council

Summer flounder SAV HAPC is defined as all native species of macroalgae, seagrasses, and freshwater and tidal macrophytes in any size bed, as well as loose aggregations, within adult and juvenile summer flounder EFH. In locations where native species have been eliminated from an area, then exotic species are included.

Notes:

NMFS. n.d. Essential Fish Habitat (EFH) Mapper (New England/Mid-Atlantic).

https://www.habitat.noaa.gov/apps/efhmapper/efhreport/. Accessed on 28 March 2024.

NMFS. 1999. Fishery Management Plan for Atlantic Tunas, Swordfish and Sharks. NOAA, National Marine Fisheries

Service, Highly Migratory Species Management Division. Silver Spring, Maryland.

NMFS. 2006. Final Consolidated Atlantic Highly Migratory Species Fishery Management Plan. National Oceanic and

Atmospheric Administration, National Marine Fisheries Service, Office of Sustainable Fisheries, Highly Migratory Species Management Division, Silver Spring, Maryland. 1,600 pp.

No EFH Areas Protected from Fishing were identified at the project location.

4. ANALYSIS OF EFFECTS ON MANAGED SPECIES, EFH, AND HAPC

Within the proposed action area, there is EFH for 11 federally managed fish species and HAPCs for two species. The potential impacts to EFH and HAPC are included in this assessment. The NOAA Fisheries Essential Fish Habitat Assessment for Consultations Guidelines for Completing an EFH assessment (NMFS 2021a) were used to identify the stressors associated with the project activities. These stressors and their effects are described below.

The project will result in temporary and permanent impacts. Temporary impacts include noise and increased turbidity associated with cofferdam installation, dredging, installation and removal of BMPs/avoidance and minimization measures (e.g., turbidity curtain.), and increased vessel traffic associated with project activities.

Norfolk Naval Shipyard, Portsmouth, August 2024

Permanent impacts to the river bottom will result from the installation of a cofferdam with sheets and piles cut at the mudline, installation and abandonment of a concrete tremie slab, and removal of approximately 1,750 cubic yards of material.

4.1 Noise Propagation from Pile Installation and Removal

Noise is often defined as any sound that is undesirable because it interferes with communication, is intense enough to damage hearing, or diminishes the quality of the surrounding environment.

Response to noise varies by the type and characteristics of the noise source; distance from the source; receptor sensitivity; and time of day. Noise can be intermittent or continuous, steady, or impulsive, and it may be generated by either mobile or stationary sources. Changes in noise are typically measured and reported using a weighted sound intensity (or level), which represents sound heard by the human ear and is measured in units called decibels (dB).

Pile driving in the immediate area of DD3 will generate underwater noise that potentially could affect listed species. Noise is often defined as any sound that is undesirable because it interferes with communication, is intense enough to damage hearing, or diminishes the quality of the surrounding environment. Response to noise varies by the type and characteristics of the noise source; distance from the source; receptor sensitivity; and time of day. Noise can be intermittent or continuous, steady, or impulsive, and it may be generated by either mobile or stationary sources.

Transmission loss (TL) underwater is the decrease in acoustic intensity as an acoustic pressure wave propagates out from a source until the source becomes indistinguishable from ambient sound.

TL parameters vary with frequency, temperature, sea conditions, current, source and receiver depth, water depth, water chemistry, and bottom composition and topography. A “practical spreading” value of 15 (referred to a “practical spreading loss”) is widely used for intermediate or spatially varying conditions when actual values for TL are unknown. This value was used to model the estimated range from pile driving activity to various expected sound pressure levels (SPLs) at the project location. This model follows a geometric propagation loss based on the distance from the driven pile, resulting in a 4.5 dB reduction in level for each doubling of distance from the source. In this model, the SPL at some distance away from the source (e.g., driven pile) is governed by a measured source level, minus the TL of the energy as it dissipates with distance. The TL equation used for fish is:

Transmission Loss (TL) = 15 * Log10[radius]

The key components of this analysis include (1) the definition of acoustic source levels;

(2) mathematical models and assumptions for acoustic transmission loss from the source; (3) the application of thresholds for different levels of effect on fish to determine the distances within which those thresholds are exceeded; and (4) mapping the resulting model of acoustic transmission loss onto the project area using geographical information…