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National Environmental Policy Act; Development of Advanced Radioisotope Power Systems

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Information about this document as published in the Federal Register.

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National Aeronautics and Space Administration.


Extension of the scoping period.


Pursuant to the National Environmental Policy Act of 1969, as amended (NEPA) (42 U.S.C. 4321 et seq.), the Council on Environmental Quality Regulations for Implementing the Procedural Provisions of NEPA (40 CFR parts 1500-1508), and NASA's policy and procedures (14 CFR subpart 1216.3), NASA announced its intent to conduct scoping and to prepare a Tier I Environmental Impact Statement (EIS) for the development of advanced Radioisotope Power Systems (RPSs) on April 22, 2004 in the Federal Register (69 FR 21867). This notice is to inform the public that the scoping period for the Advanced Radioisotope Power Systems EIS has been extended through July 30, 2004.

NASA, in cooperation with the U.S. Department of Energy (DOE), proposes to develop two types of advanced RPSs to satisfy a wide of range of future space exploration mission requirements. These advanced RPSs would be capable of functioning in the vacuum of space and in the environments encountered on the surfaces of the planets, moons and other solar system bodies. These power systems would be based upon the General Purpose Heat Source (GPHS) previously developed by DOE and used in the Radioisotope Thermoelectric Generators for the Galileo, Ulysses, and Cassini missions. The advanced RPSs would be capable of providing long-term, reliable electrical power to spacecraft across the range of conditions encountered in space and planetary surface missions. The Tier I EIS will address in general terms the development and qualification for flight of advanced RPSs using passive or dynamic systems to convert the heat generated from the decay of plutonium to electrical energy, and research and development of technologies that could enhance the capability of future RPS systems. This development activity would include, but not necessarily be limited to: (1) New power conversion technologies to more efficiently use the heat energy from the GPHS module, and (2) improving the versatility of the RPS so that it would be capable of operating for extended periods both in the vacuum of space and in planetary atmospheres. For more detailed information see the original Federal Register notice cited above.


Interested parties are invited to submit comments on environmental concerns in writing on or before July 30, 2004, to assure full consideration during the scoping process.


Comments should be addressed to Dr. George Schmidt, NASA Headquarters, Code S, Washington, DC 20546-0001. While hardcopy comments are preferred, comments may be sent by electronic mail to:

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Dr. George Schmidt, NASA Headquarters, Code S, Washington, DC 20546-0001, by telephone at 202-358-0113, or by electronic mail at

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Jeffrey E. Sutton,

Assistant Administrator for Institutional and Corporate Management.

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[FR Doc. 04-16592 Filed 7-20-04; 8:45 am]