Army Research Laboratory, Watertown Mall Area Site

AGENCY:

Nuclear Regulatory Commission.

ACTION:

Notice of removal of the Watertown Mall Area Site from the Nuclear Regulatory Commission Site Decommissioning Management Plan in Watertown, Massachusetts.

SUMMARY:

The Nuclear Regulatory Commission (NRC) has removed the Watertown Mall Area site in Watertown, Massachusetts, from the NRC Site Decommissioning Management Plan (SDMP). In 1990, NRC developed the SDMP program for approximately 50 sites that warranted additional NRC oversight to ensure the timely and safe decommissioning of sites with residual radioactive material in excess of NRC's criteria for release for unrestricted use and license termination. One of these sites was the Watertown Arsenal/Mall area site. In 1997, the Army Research Laboratory (ARL) portion of the Watertown Arsenal Mall site was removed from the SDMP, having met the SDMP Action Plan criteria (as specified in 57 FR 13389) for release for unrestricted use. At the time the Watertown Arsenal was removed from the SDMP, radiological assessments had been completed for a majority of the Mall Area, which indicated that it could be released for unrestricted use. However, these assessments also indicated that there was the potential for residual radioactive material in excess of NRC SDMP criteria to be present in buried drain/sewer lines on the site that had not yet been evaluated. The Watertown Mall Area is currently authorized under the Source Material License SUB-238 as a storage-only license. In a letter dated July 10, 2000, ARL, the licensee, requested removal of the Mall Area from the SDMP and provided a dose assessment and demonstration that residual radioactive material in the buried drain/sewer lines satisfy NRC's and the Commonwealth of Massachusetts's criteria for release for unrestricted use.

This administrative action removes the Watertown Mall site from the SDMP. There is no licensing action before NRC at this time. The SUB-238 license will not be terminated, as the ARL, the U.S. General Services Administration (GSA), and the U.S. Army Corps of Engineers (hereafter, the Corps) are evaluating whether to request an amendment to SUB-238 to add another SDMP site, the GSA property in Watertown, rather than terminating the license with the removal of the Watertown Mall. The GSA property is currently not licensed by NRC, but the radiological assessment and remediation of the GSA property is managed by the Corps under the Formerly Utilized Defense Sites program. The GSA property had been part of the Watertown Arsenal/Mall before 1968.

Background

In 1967-1968, the eastern half of the Watertown Arsenal (referred to as the Watertown Mall area site), encompassing 24 hectares (59 acres) and 21 buildings, including three buildings involved in licensed material use (Buildings 34, 41, and 421), was declared excess government property, transferred to the GSA, and subsequently sold to the Watertown Redevelopment Authority. The area where two of the buildings involved in licensed material use were located are now parking lots for retail stores. The concrete pads for two of the buildings were broken up and left in place during redevelopment of the Watertown Mall Area. The concrete pad for the third building is a foundation for tennis courts. In 1990, the Watertown Mall was added to the SDMP, because records available to the U.S. Army and NRC did not clearly demonstrate that necessary decontamination occurred before the property was released for unrestricted use. During the past 10 years, ARL and the Corps have performed historical record reviews, surveys, and radiological assessments to address the concerns regarding residual radioactive material at the site. NRC staff has completed its review of these records and assessments, and has determined that no additional remediation is required. Radiation levels above ground are consistent with levels of natural background radiation, and residual radioactive material levels in the soil are generally consistent with natural background levels. A few areas have been identified that contain residual radioactive material in excess of background levels, but most are less than the SDMP Action Plan criteria.

One sewer line, an inactive line from the former Building 41, has residual fixed contamination in excess of the SDMP Action Plan criteria. The dose assessment developed by the ARL and validated by NRC indicated that potential radiological doses to the public would not be in excess of the NRC criteria for release for unrestricted use. Also, an evaluation of the historical records indicated that doses from the relatively small spots of contamination identified on the concrete pads from Buildings 34 and 421 that are below the parking lot and tennis courts, respectively, were well below the current NRC dose-based release criteria at 10 CFR part 20, Subpart E.

Accordingly, the staff has concluded that the Watertown Mall Area site is acceptable for unrestricted use.

The ARL July 10, 2000, request is available for review in the NRC's Public Electronic Reading Room on the NRC Web site at: http//NRC.GOV/ADAMS/INDEX/HTML (ARL Letter dated July 10, 2000, ML003733963). Persons wishing to review this document at the Region I Office should call Ms. Sheryl Villar at (610) 337-5239 several days in advance, to assure that the document will be readily available for review. For questions regarding this administrative action to remove the Watertown Mall Area site from the SDMP, please contact Marie Miller, Decommissioning and Laboratory Branch, Division of Nuclear Materials Safety, Region I, at (610) 337-5205.