The US Minerals Management Service has issued a draft environmental impact statement (EIS) on the possible effects of using floating production, storage, and offloading (FPSO) systems at deepwater fields in the US Gulf of Mexico. The draft EIS concludes that the potential site-specific effects of using FPSOs are essentially the same as with other deepwater development systems.
MMS said storing oil in FPSOs until it can be moved to shore via tankers or barges can allow the industry to operate in waters that exceed the capabilities of current production techniques and transportation systems. The EIS defined deepwater as more than 200 m (656 ft).
The draft EIS said that the main oil spill risk associated with FPSO use is from shuttle tankers, not FPSOs themselves; that FPSO risks are comparable to those from other deepwater systems and from pipelines; and that excluding FPSOs would not reduce cumulative environmental impacts because other systems would be used instead.
The study said emissions from shuttle tankers could exceed air quality limits in the Breton Class 1 Area off Louisiana. The draft EIS was limited to the Central and Western Gulf of Mexico planning areas.
MMS said the generic study's base case assumed a permanently moored, double-hulled, ship-shaped FPSO with capacity of 1 million bbl. The EIS assumed seafloor well equipment and onboard production equipment would be the same as that used at other deepwater production facilities.
It assumed crude would be offloaded and transported to Louisiana and Texas ports or to the Louisiana Offshore Oil Port and that associated gas would be moved to shore via pipeline.
MMS will accept comments on the draft EIS until Oct. 10. The comments will be considered before it drafts a final EIS or decides on allowing FPSO use in the gulf.
Public hearings will be held Sept. 18 in Mobile, Ala.; Sept. 19 in New Orleans; Sept. 21 in Lake Charles, La.; and Sept. 20 in Houston.
