Notice of the Availability of a Draft Environmental Assessment
The National Science Foundation (NSF) gives notice of the availability of a draft Environmental Assessment (EA) for proposed activities in the Indian Ocean.
The Division of Ocean Sciences in the Directorate for Geosciences (GEO/OCE) has prepared a draft Environmental Assessment for a low-energy marine seismic survey by the Research Vessel Roger Revelle in the northeastern Indian Ocean, in international waters (1600-5100 meters depth) roughly between 5° N and 25° S, along ˜90° E during May-August 2007. The draft Environmental Assessment is available for public review for a 30-day period.
Comments must be submitted on or before March 9, 2007.
Copies of the draft Environmental Assessment are availableupon request from; Dr. William Lang, National Science Foundation, Division of Ocean Sciences, 4201 Wilson Blvd., Suite 725, Arlington, VA 22230. Telephone: (703) 292-7857. The draft is also available on the agency's Web site at http://www.nsf.gov/geo/oce/pubs/Scripps_NE_Indian_Ocean_EA.pdf.
The Scripps Institution of Oceanography (SIO), with research funding from the NSF, plans to conduct scientific research at nine sites in international waters on the Ninety East Ridge in the northeastern Indian Ocean for ˜55 days during May-August 2007. Research activities will include rock-dredging and magnetic, bathymetric, and seismic surveys. The seismic survey will use a towed array of two generator/injector (GI) airguns, totaling an air discharge volume of 90 in 3. The GI guns will be used for ˜49 h at each of 5 sites on the Ninety East Ridge in water depths of 1600 to 5100 meters. The results will be used to study the morphology, structure, and tectonics of ridge volcanoes, to infer the magmatic evolution of the ridge, and to survey broad characteristics of subseafloor in order to refine the planning of an Integrated Ocean Drilling Program (IODP) drilling proposal.
SIO has applied for the issuance of an Incidental Harassment Authorization (IHA) from the National Marine Fisheries Services (NMFS) to authorize the incidental harassment of small numbers of marine mammals during the seismic survey. The information in this Environmental Assessment supports the IHA permit application process, provides information on marine species not covered by the IHA, and addresses the requirements of Executive Order 12114, “Environmental Effects Abroad of Major Federal Actions”. Alternatives addressed in this EA consist of a corresponding seismic survey at a different time, along with issuance of an associated IHA; and the no action alternative, with no IHA and no seismic survey.
Numerous species of cetaceans and sea turtles occur in the northeastern Indian Ocean. Several of the species are listed as Endangered under the U.S. Endangered Species Act (ESA), including humpback, sei, fin, blue, and sperm whales. Other species of special concern that could occur in the area include the endangered (under the ESA) leatherback and hawksbill turtles, and the threatened (under the ESA) loggerhead, olive ridley, and green turtles.
The potential impacts of the seismic survey would be primarily a result of the operation of small airguns, although a multi-beam sonar and a sub-bottom profiler will also be operated. Impacts may include increased marine noise and resultant avoidance behavior by marine mammals, sea turtles, and fish; and other forms of disturbance. The operations of the project vessel during the study would also cause a minor increase in the amount of vessel traffic. An integral part of the planned survey is a monitoring and mitigation program designed to minimize the impacts of the proposed activities on marine mammals and sea turtles that may be present during the proposed research, and to document the nature and extent of any effects. Injurious impacts to marine mammals and sea turtles have not been proven to occur near airgun arrays; however, the planned monitoring and mitigation measures would minimize the possibility of such effects should they otherwise occur.
Protection measures designed to mitigate the potential environmental impacts will include the following: A minimum of one dedicated marine mammal observer maintaining a visual watch during all daytime airgun operations, and two observers for 30 min. before start up. The small size of the airguns, restricting their use to deep (1600-5100 m) water, and ramp-up and shut-down procedures are also inherent mitigation measures. SIO and its contractors are committed to apply those measures in order to minimize disturbance of marine mammals and sea turtles, and also to minimize the risk of injuries or of other environmental impacts.
With the planned monitoring and mitigation measures, unavoidable impacts to each of the species of marine mammal that might be encountered are expected to be limited to short-term localized changes in behavior and distribution near the seismic vessel. At most, such effects may be interpreted as falling within the Marine Mammal Protection Act (MMPA) definition of “Level B Harassment” for those species managed by NMFS. No long-term or significant effects are expected on individual marine mammals, or the populations to which they belong, or their habitats. The agency is currently consulting with the NMFS regarding species within their jurisdiction potentially affected by this proposed activity.
Copies of the draft EA, titled “Environmental Assessment of Planned Low-Energy Marine Seismic Survey by the Scripps Institution of Oceanography in the Northeast Indian Ocean, May-August 2007,” are available upon request from: Dr. William Lang, National Science Foundation, Division of Ocean Sciences, 4201 Wilson Blvd., Suite 725, Arlington, VA 22230. Telephone: (703) 292-7857 or at the agency's Web site at:http://www.nsf.gov/oce/pubs/Scripps NE_Indian_Ocean_EA.pdf. The NSF invites interested members of the public to provide written comments on this draft EA.Alexander Shor, Program Director, Environmental Operations, Division of Ocean Sciences, National Science Foundation.