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Offshore Deepwater Liquified Natural Gas (LNG) Ports

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EPA received three National Pollution Discharge Elimination System (NPDES) permit applications for wastewater discharges related to the construction and operation of deepwater LNG ports in state and federal waters of Massachusetts Bay. One was for construction-related discharges associated with the Northeast Gateway LNG deepwater port, one was for operations-related discharges associated with the Northeast Gateway LNG deepwater port, and the other was for both construction-related and operations-related discharges for the Neptune LNG deepwater port.

On June 13, 2007, EPA issued a final NPDES permit for discharges related to the construction of an offshore deepwater LNG port and new gas pipelines to provide a connection from the new port to existing gas transmission lines, by Algonquin Gas Transmission, LLC (Algonquin) and Northeast Gateway Energy Bridge, LLC (Northeast Gateway). This permit (MA0040240) became effective on July 23, 2007.

On October 27, 2007, EPA issued a final NPDES permit for discharges associated with the operation of the Northeast Gateway LNG deepwater port (MA0040266). This permit became effective on November 26, 2007.

On June 6, 2008, EPA issued a final NPDES permit for discharges associated with the construction of a new gas pipeline and deepwater port and the operation of the Neptune Deepwater Port (MA0040258). This permit became effective on August 1, 2008. On September 25, 2008, Neptune LNG LLC applied to the EPA to modify NPDES permit MA0040258 to allow the discharge of hydrostatic test water containing corrosion inhibitor from its new subsea pipeline which connects the Neptune LNG Deepwater Port with the existing Spectra HubLine. In response to the application, EPA issued a draft permit modification on February 19, 2009. The public comment period for the draft permit modification ends on March 20, 2009.

Neptune Deepwater LNG Port - (NPDES Permit Number MA0040258)

The NPDES permit authorizes Neptune LNG, LLC (Neptune) to withdraw water from, and discharge pollutants to, Massachusetts Bay from its new deepwater port during construction and operation of the port. New pipelines will facilitate the delivery of regasified LNG from the deepwater port to onshore markets in New England, connecting to the existing offshore and land based natural gas distribution system. Specifically designed ships containing LNG will deliver regasified natural gas into a new gas pipeline via the new offshore terminal. The Neptune deepwater port will be located in federal waters in the eastern side of Massachusetts Bay, approximately 22 miles northeast of Boston in a water depth of approximately 260 feet.

This permit took effect on August 1, 2008. Construction began in July 2008 and will continue through Fall 2009.

The permit modification will authorize the discharge of hydrostatic test water containing corrosion inhibitor following treatment to remove toxicity. The current permit authorizes the discharge of hydrostatic test water without any chemical additives. The public comment period for the draft permit modification began on February 19, 2009 and ends on March 20, 2009.

Contact:
Ellen Weitzler (weitzler.ellen@epa.gov)
US EPA
5 Post Office Square, Suite 100
Mail Code: 06-1
Boston, MA 02114
Tel: (617) 918-1582
Fax: (617) 918-0582

Neptune Deepwater Port documents:

Northeast Gateway LNG Deepwater Port - (NPDES Permit Number MA0040266)

The NPDES permit is to authorize Northeast Gateway to withdraw seawater (for cooling) from, and discharge pollutants to, Massachusetts Bay from its new deepwater port. The new port is for the regasification of liquefied natural gas (LNG) and the transmission of the gas into a network of undersea natural gas transmission pipelines. The LNG will be delivered to the port by specially equipped LNG tanker vessels. The LNG tankers will connect to, and become integrated within, the deepwater port by coupling with one of the facilities two "submerged turret loading buoys." These buoys are, in turn, connected to the existing undersea transmission pipeline network by flexible risers, subsea flowlines and pipeline laterals. Once integrated within the deepwater port, the LNG tankers will regasify their cargo of LNG using their specially designed onboard regasification equipment. Following regasification, the natural gas will be odorized and metered out, through the flexible risers and subsea flowlines, to the pipeline laterals and the undersea pipeline transmission network. Thus, the deepwater port will be the functional equivalent of a land-based or marine platform-based LNG regasification and import terminal, although the regasification and transmission of the gas will occur on the tanker vessels.

The Northeast Gateway deepwater port will be located in federal waters of Massachusetts Bay approximately 13 miles south-southeast of Gloucester, Massachusetts. This permit addresses cooling water withdrawals and pollutant discharges associated with operation of the deepwater port. Discharges associated with construction of the port were addressed in NPDES Permit MA0040240.

This permit became effective on July 23, 2007. Pipeline and port construction is complete.

Northeast Gateway Deepwater Port (MA0040266) documents:

Northeast Gateway Energy Bridge Pipeline Lateral Project - (NPDES Permit Number MA0040240)

The discharge is the result of construction of three new natural gas pipelines to service a new LNG port in Massachusetts Bay. The new pipelines will facilitate the delivery of regasified LNG from the planned Northeast Gateway Energy Bridge Deepwater Port (Northeast Port) to onshore markets in New England. The new gas pipelines will be buried on the ocean floor. One of the new pipelines (the Pipeline Lateral) will be built by Algonquin Gas Transmission, LLC (Algonquin) and two (Flowlines A and B) will be built by Northeast Energy Bridge, LLC (NEG) which will also be constructing the remaining Northeast Port infrastructure. Although the three pipelines will have two different owners, they will be constructed by a single contractor as one project. Therefore, Algonquin and NEG are co-permittees on a single NPDES permit. Discharges and seawater intakes associated with the operation of the Northeast Port are not included in the final permit.

The one time discharge consists of 1.99 million gallons of seawater treated with Tetrakis hydroxymethyl phosphonium sulfonate (THPS) biocide and neutralized with hydrogen peroxide. Up to 1.99 million gallons of biocide treated seawater will be discharged in Massachusetts Bay within Massachusetts coastal waters (Outfall 001). Contingent discharge locations (Outfalls 002 and 003) for 85,000 gallons of biocide treated seawater beyond Massachusetts waters and within federal jurisdiction, are included in this permit. The permit will be terminated upon completion and testing of the pipeline.

The NPDES permit requires that the THPS biocide be neutralized with hydrogen peroxide to 4.4 mg/l THPS or less in addition to limitations on flow, total suspended solids, pH and dissolved oxygen.

This permit became effective on July 23, 2007. Construction of the pipelines is complete.

Northeast Gateway Energy Bridge Pipeline Lateral Project (MA0040240) documents: