DOE OSTI2018
Following the completion of a Soil and Groundwater Remedial Investigation by USACE at a FUSRAP site located in Nassau County, New York, groundwater data indicated the presence of contaminant source(s) that had not been identified. As a result, a targeted investigation was undertaken to understand how materials were handled and disposed of at a site located in Nassau County, Long Island, New York. The FUSRAP site is a 4.3-hectare (10.5-acre) site encompassing three parcels which had historically been utilized as a nuclear materials manufacturing facility (e.g., cores, slug, and fuel elements) for reactors used in both research and electric power generation in early 1950's until late 1960's; however, the targeted investigation was on the southern-most parcel known as the '70 Property' (the Site). The 70 Property contained a building that was used for atomic fuel-element manufacturing from 1958 until 1966 under license to the Atomic Energy Commission (AEC), and involved the use of natural, enriched, and depleted uranium as well as lesser amounts of thorium. The major contaminants of concern are tetrachloroethene, nickel, uranium and thorium. During the RI, significant sources of contamination were not found in Site soils despite records indicating that chemicals and radionuclides had been disposed of on the property. In addition, downgradient groundwater data indicated a source(s) on the 70 Property that could not be identified by known sources on other the other FUSRAP parcels or from adjacent sites. This conclusion was further supported following development of groundwater contaminant transport and flow models. The main objective of the targeted investigation was to evaluate the potential discharge points on the 70 Property that may have been utilized for liquids waste disposal. However, several challenges existed including 1) lack of building construction details; 2) historical changes to Site building and property; 3) the use of the Site by various tenants; and 4) the commingling of Site contaminants with impacts from multiple sources. To overcome these challenges, historic documents/reports with information about the handling and disposal of liquid wastes were reviewed to evaluate quantities, contents and locations of waste disposal. Thereafter, an investigation was undertaken that included geophysical surveys; pipe tracing and video inspection; in-situ smoke and water testing; installation of test trenches and soil borings; and, sampling sludge residuals, soils and water within the various drainage structures that were located. This paper describes the multi-faceted investigation approach that was utilized to overcome the challenges faced during the investigation as well as insights into the waste disposal practices of the time period and the findings of the investigation. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗