Offshore Berth Project
Weaver's Cove Energy is proposing to construct an offshore berth in Mount Hope Bay. This berth will be capable of receiving LNG tankers, supporting LNG unloading operations and moving the LNG in liquid form through insulated underwater transfer lines to the storage tank at the onshore facility. Consistent with our previous project plans, the LNG will be stored and subsequently vaporized for transport through pipelines to homes and businesses throughout the region; or, it will be transported via truck from the terminal as a liquid to "peakshaving" storage tanks, such as the one on Bay Street in Fall River.
Offshore Berth Project
Weaver's Cove Energy is proposing to construct an offshore berth in Mount Hope Bay. This berth will be capable of receiving LNG tankers, supporting LNG unloading operations and moving the LNG in liquid form through insulated underwater transfer lines to the storage tank at the onshore facility. Consistent with our previous project plans, the LNG will be stored and subsequently vaporized for transport through pipelines to homes and businesses throughout the region; or, it will be transported via truck from the terminal as a liquid to "peakshaving" storage tanks, such as the one on Bay Street in Fall River
Original Proposal
In 2005, the Federal Energy Regulatory Commission (FERC) authorized the siting, construction, and operation of the Weaver’s Cove’s LNG terminal on an approximately 73-acre brownfield site located in the City of Fall River, Massachusetts. The Approved Project site is located on the eastern bank of the lower Taunton River approximately 2.2 miles north of the Braga Bridge (Interstate-195).
The FERC-approved original proposal consisted of the design and licensing of an LNG terminal comprising:
- Ship unloading jetty, capable of receiving standard capacity LNG tankers (typically 145,000 m3)
- A single 200,000 m3 LNG storage tank, (4.3 BCF of gas equivalent), using a "full containment" design
- Vaporization system for 400 million cubic feet per day (MMCFD) baseload send out capacity (800 MMCFD peak capacity)
- LNG truck loading facilities
The original facility would be conceptually similar to the existing Fall River Gas (now New England Gas) LNG plant. The main differences between the two facilitiesare that the terminal at Weaver's Coveis larger and will use more advanced design and construction technology. The Weaver’s Cove facility will receive gas via ship and the Fall River Gas facility received LNG via truck.
In addition, two new 24-inch natural gas pipelines will be developed by Mill River Pipeline, LLC, a sister company to Weaver's Cove Energy, to link the facility to the existing Algonquin Gas Transmission Company interstate natural gas transmission system. (For more information on the pipelines, click here.) Additionally, the original proposal called for the dredging of the Taunton River channel leading to the project site and the expansion and deepening of the turning basin at the site. Materials dredged were deemed appropriate by the Army Corps of Engineers for offshore disposal well outside of Narragansett Bay.
The initial terminal was designed to accommodate standard capacity LNG tankers, which are typically about 950 feet long, 150 feet on the beam, and have a typical loaded draft of about 37.5 feet
Offshore Berth Proposal
Weaver’s Cove proposes to amend FERC’s approval authorizing the siting, construction, and operation of the LNG terminal by seeking approval to construct, own, and operate an offshore berth in Mount Hope Bay in Massachusetts waters; as well as an approximately 4.25-mile-long LNG transfer system, which includes buried submarine LNG transfer lines using insulated pipe-in-pipe (PiP) technology. LNG delivered by LNG ships will be unloaded at the offshore berth and transferred through the LNG transfer system to the LNG storage tank at the LNG terminal site in Fall River. The project will include development of a turning basin, referred to as the “Mount Hope Bay turning basin” to accommodate LNG tanker turning maneuvers where the tankers leave the existing federal navigation channel and enter a proposed new approach channel providing access to the berth site. To integrate the proposed Offshore Berth Project with the Approved Project, most of the dredging that was anticipated in the lower Taunton River as part of the Approved Project will no longer be conducted because it will no longer be necessary for the LNG tankers to transit beyond the proposed offshore berth approach channel located south of the Braga Bridge in Mount Hope Bay.
Offshore Berth - Structure and Access
The offshore berth structures will consist of a central platform supporting the LNG unloading equipment, mooring dolphins for securely berthing an LNG tanker. A separate spill impoundment sump will be installed to the west side of the platform and connected to it by an inclined spillway. The platform will be a three-level structure, approximately 250 feet by 125 feet, supporting the unloading arms, associated LNG and vapor handling equipment, control room, fire-fighting pumps and monitors, emergency equipment, and utilities. Offshore berth access is limited to water craft only as the proposed offshore berth is about one mile from land.
The proposed transit route for LNG tankers that will call at the proposed offshore berth is the same as that assessed in the Commission's final EIS for the Approved Project and accepted in FERC's Approval Orders up to the point of the proposed Mount Hope Bay turning basin. The transit route extends approximately 17 nautical miles (nm) from entry into Narragansett Bay to the proposed offshore berth in Mount Hope Bay. The entire length of the LNG tanker transit route to the proposed Mount Hope Bay turning basin was the subject of a comprehensive reveiw by FERC staff and the United States Coast Guard as part of the National Environmental Policy Act (NEPA) analysis for the Approved Project culminating with the final Environmental Impact Statement (EIS). Under the proposed Offshore Berth Project, neither the waterway characteristics nor the size or frequency of the LNG tanker traffic has changed from that proposed for the Approved Project for the LNG tanker transit route between the entrance to Narragansett Bay and the proposed Mount Hope Bay turning basin. The dredging of the federal navigation channel south of the Mount Hope Bay turning basin in Massachusetts and Rhode Island also remains unchanged.
The offshore berth will be capable of receiving LNG tankers of similar dimensions to those proposed in Weaver’s Cove’s original Letter of Intent filed with the United States Coast Coast Guard on May 12, 2004: “Typical dimensions of such vessels are length 950 feet, beam 145 feet and draft 37.5 feet.” LNG tankers will be in full compliance with all applicable United States Coast Guard regulations and with the International Gas Carrier Code (IGC Code) governing the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk. Pilotage of LNG tankers will be provided by the Northeast Marine Pilots. As described in Weaver’s Cove’s previous application and the final EIS for the Approved Project, tug support will be required for all phases of arrival and departure of the LNG tankers, for channel navigation by the tankers, and for standby and fire fighting cover duties during cargo transfer operations at the berth. A full training program is being prepared to qualify a number of pilots in the handling of LNG tankers and in the optimal utilization of tractor tugs. Only pilots who have satisfactorily completed the training course will be employed by Weaver’s Cove for tanker transits to the offshore berth.
Pipe-in-Pipe (PiP) Transfer System
The proposed PiP transfer system will be approximately 4.25 miles long and extend underwater for nearly all of its length from the offshore berth through Mount Hope Bay and the lower Taunton River to a terminus at the LNG terminal site The submerged lands in Mount Hope Bay and the lower Taunton River will be trenched to accommodate the placement of the PiP transfer system and backfilled with a minimum of 4 feet of cover (nominal cover of 5 feet) over the top of the transfer lines.
The submerged portion of the PiP transfer system will be installed to the west of and approximately parallel to the existing federal navigation channel. The PiP transfer system will come ashore at the LNG terminal site and continue for approximately 370 feet to connect with new plant piping going to the LNG storage tank.
Storage and Processing Facilities
As in the Original Proposal, the terminal will be developed with one LNG storage tank of approximately 200,000 cubic meter capacity, compared to the typical ship's capacity of 145,000 cubic meters. The tank will utilize the "full containment" design. Essentially, this means that it will be a "storage tank within a storage tank". The inner tank will be constructed from 9% nickel steel to contain the LNG, surrounded by insulation to minimize heat leaking into the LNG. The outer tank will be a thick-walled, pre-stressed steel reinforced concrete tank designed to contain the LNG in the extremely unlikely event of a leak in the inner tank.
The processing facilities will comprise pumps, piping, heat exchangers, odorization equipment, metering facilities and control systems to transform the LNG from a liquid to natural gas at room temperature and deliver the natural gas to the pipeline grid. Odorant will be injected into the natural gas, as required by law and consistent with U.S. Department of Transportation safety standards adopted by the gas pipeline and distribution companies, since natural gas in its untreated state has no smell. The heat for the exchangers will be provided by a hot water/glycol mixture heated in natural gas-fired boilers. In addition, the terminal will also be capable of loading LNG onto trucks for delivery to satellite LNG peakshaving facilities throughout the region.
