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Radiation Protection

How can I contact MARSSIM workgroup members?

Four agencies currently meet as part of the MARSSIM Workgroup: The Department of Defense (DOD), the Department of Energy (DOE), the Nuclear Regulatory Commission (U.S.NRC), and the EPA. These agencies have the primary responsibility for managing radioactive materials in the United States.

To contact the MARSSIM Workgroup, please call or email Kathryn Snead, of the U.S. Environmental Protection Agency, at 202-343-9228, or

For more information, visit MARSSIM Workgroup Materials.

Return to Frequent Questions about Radiation Protection.