Environmental assessment of a low-energy marine geophysical survey by the R/V Marcus G. Langseth in the Central Pacific Ocean, May 2012 Low-energy marine geophysical survey by the R/V Marcus G. Langseth in the Central Pacific Ocean, May 2012 Environmental assessment for L-DEO's Line Islands seismic survey, 2012 National Science Foundation's environmental assessment and Finding of No Significant Impact determination pursuant to the National Environmental Policy Act, 42 U.S.C. 4321, et seq. and Executive Order 12114, marine geophysical survey by the R/V Marcus G. Langseth in the Central Pacific Ocean, May, 2012 Draft environmental assessment and determination pursuant to the National Environmental Policy Act (NEPA), 42 U.S.C. 4321, et seq. and Executive Order 12114, Marine geophysical survey in the Central Pacific Ocean, May 2012

"Lamont-Doherty Earth Observatory (L-DEO), with funding from the U.S. National Science Foundation (NSF), plans to conduct a marine coring and low-energy seismic survey in the Line Islands ~1800 km south of Hawaii in the central Pacific OCean during May 2012. The survey will take place partly in the Exclusive Economic Zone (EEZ) of the Republic of Kiribati and partly in the U.S. EEZ, in water depths of ~1100-5000m. The sesmic survey will use a towed pair of 105-in³ GI airguns. On behalf of L-DEO, the U.S. State Department will seek authorization from the Republic of Kiribati for clearance to work in its EEZ. NSF, as the funding and action agency, has a mission to 'promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense.'. The sesmic survey is part of a research proposal that has been identified as an NSF program priority and is recommended for funding. It will provide data necessary to understand sedimentation patterns on the flanks of the Line Islands Ridge and how important climate patterns have varied in the late Pleistocene. L-DEO is requesting an Incidental Harassment Authorization (IHA) from the U.S. National Marine Fisheries Service (NMFS) to authorize the incidental, i.e., not intentional, harassment of small numbers of marine mammals, should this occur during the seismic survey. The information in this Environmental Assessment (EA) supports the IHA application process and provides information on marine species that are not addressed by the IHA application, including seabirds, and sea turtles that are listed under the U.S. Endangered Species Act (ESA), including candidate species. The EA addresses the requirements of the National Environmental Policy Act (NEPA) and Executive Order 12114, 'Environmental Effects Abroad of Major Federal Actions'. Alternatives addressed in this EA consist of a corresponding program at a different time, along with issuance of an associated IHA; and the no action alternative, with no IHA and no seismic survey"--Abstract (page vi).