The MMS has completed its latest programmatic environmental assessment (PEA) addressing proposed development activities in the Grid 16 area. Located approximately 40 miles southeast of the Mississippi River Delta, the Grid 16 area encompasses 392 blocks or some 2.3 million acres. Water depths in this area range from 1,000 to 2,000 meters. More than 75 percent of the blocks in this grid area are currently leased. The Grid 16 PEA further evaluates the potential environmental effects for BP Exploration & Production Inc.'s "Thunder Horse" project. This is the largest development project proposed in the Gulf's history. BP proposes to drill and complete 27 wells on its Mississippi Canyon Block 777 Unit. The PEA assessed the specific and cumulative impacts associated with BP's proposal and provides information on the deepwater area within Grid 16 (see figure). On the basis the PEA, MMS concluded that BP's proposal will not significantly affect the quality of the marine and human environments and that preparation of an environmental impact statement is not warranted or required.
The MMS's Gulf of Mexico OCS Region began its grid environmental assessment program to enhance environmental review efficiencies. The National Environmental Policy Act allows Federal agencies to incorporate by reference environmental information from broad based environmental documents such as EIS's or PEA's into more narrowly defined documents such as site-specific environmental assessments or categorical exclusions. Grid PEA's are comprehensive in terms of the impact producing factors and environmental and socioeconomic resources described and analyzed. Once a PEA has been completed, it serves as a reference document for future environmental evaluations within that grid area.
Listed below is the current status of the Gulf's Grid PEA's.
- Grid 3 – Work in Progress, "Gunnison," N-7625, Garden Banks, Blocks 667, 668, and 669, Kerr-McGee
- Grid 4 -- Completed, "Nansen," N-7045, East Breaks, Blocks 602 and 646, Kerr-McGee
- Grid 7 -- Finalizing, "Magnolia," N-7506, Garden Banks, Blocks 783 and 784, Conoco
- Grid 10 -- Completed, "Holstein," N-7216, Green Canyon, Blocks 644 and 645, BP
- Grid 12 -- Completed, "Medusa," N-7269, Mississippi Canyon, Blocks 538 and 582, Murphy
- Grid 15 -- Completed, "Matterhorn," N-7249, Mississippi Canyon, Block 243, TotalFinaElf
- Grid 16 -- Completed, "Thunder Horse," N-7469, Mississippi Canyon, Blocks 775, 776, 777, 778, 819, 820, 821, and 822, BP