DOE OSTI2012
Monazite sand processing was conducted at the W. R. Grace Curtis Bay Facility (Baltimore, Maryland) from mid-May 1956 through the spring of 1957 under license to the Atomic Energy Commission (AEC), for the extraction of source material in the form of thorium, as well as rare earth elements. The processing was conducted in the southwest quadrant of a ca. 100 year old, five-story, building (Building 23) in the active manufacturing portion of the facility. Building components and equipment in the southwest quadrant of Building 23 exhibited residual radiological activity remaining from the monazite sand processing. U.S. Army Corps of Engineers (USACE) conducted a remedial investigation (RI) and feasibility study (FS) and prepared a Record of Decision (ROD) to address residual radioactivity on building components and equipment in the southwest quadrant of Building 23. The remedy selected for the southwest quadrant of Building 23, which was documented in the ROD (dated May 2005), was identified as 'Alternative 2: Decontamination With Removal to Industrial Use Levels'. The selected remedy provided for either decontaminating or removing areas of radioactivity to meet the RGs. Demonstration of compliance with the selected ARAR was performed using the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) and other appropriate guidance, as well as appropriate dose modeling codes where necessary. USACE-Baltimore District along with its private industry partner worked together under the terms of a 2008 Settlement Agreement to implement the remedial action (RA) for the southwest quadrant of Building 23. The RA was conducted in two phases: Phase 1 was completed to improve the building condition for support of subsequent remedial action and decrease scope uncertainty of the remedial action, and Phase 2 included decontamination and removal activities to meet the RGs and demonstration of compliance with the selected ARAR. Challenges encountered during the RA include: coordination with stakeholders, coordination between multiple RA contractors, addressing unique structural challenges for Building 23, nonradiological hazards associated with the RA, weather issues, and complex final status survey (FSS) coordination. The challenges during the Phase 1 RA were handled successfully. The challenges for the Phase 2 RA, which is anticipated to be complete by late-summer of 2012, have been handled successfully so far. By fall of 2012, USACE is expecting to finalize a robust RA Closure Report, including the Final Status Survey Report, which summarizes the RA activities and documents compliance with the ROD. During the ongoing RA at Building 23, there have been and still are many challenges both technically and from a project management perspective, due in part to the nature and extent of impact at the site (residual radioactivity within an active processing building), dual oversight by the property owner and USACE, and site-specific challenges associated with a complex RA and multiple contractors. Currently, USACE and its industry partner are overseeing the completion of RA field activities. RA closure documentation for the remediation of Building 23 to address residual contamination in building materials will be reviewed/approved by USACE and its industry partner upon completion of the field activities. USACE and its industry partner are working well together, through the Settlement Agreement, to conduct a cost-efficient and effective remedial action to address the legacy issues at Building 23. This cooperative effort has set a firm foundation for achieving a successful RA at the RWDA using a 'forward think' approach, and it is a case study for other sites where an industry partner is involved. The collaborative effort led to implementation of an RA which is acceptable to the site owner, the regulators, and the public, thus allowing USACE to move this project forward successfully in the FUSRAP program. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗