Application of MARSSIM at the Big Rock Point Restoration Project

Big Rock Point was Michigan's first commercial power reactor and operated for 35 years. It was permanently shut down in August of 1997, and the site is currently being returned to its natural state. Guidance contained in the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) is being applied in preparation for the final status survey. Unlike other commercial power reactors currently undergoing decommissioning, all Big Rock Point structures will be removed prior to the final status survey. A historical site assessment along with characterization surveys formed the basis to designate 1.6 square kilometers (395.9 acres) of the site as non-impacted and the remaining 0.7 square kilometers (184.5 acres) as impacted as defined by MARSSIM. Also, a source term abstraction has been performed using historical waste stream data to identify radionuclides potentially present in site soils, hard-to-detect (HTD) radionuclides and surrogate radionuclides for the HTD radionuclides.