Radon in Soil Gas Above Bedrock Fracture Sets at the Shepley???s Hill Superfund Site

J.R. Giles ; T.L. McLing ; M.V. Carpenter ; C.J. Smith ; W. Brandon

关键词: Fracture;    Radon;    Soil Gas;   

DOI  :  10.2172/1070114
RP-ID  :  INL/EXT-12-27844
PID  :  OSTI ID: 1070114

学科分类：地球科学(综合)

美国|英语

来源: SciTech Connect

【 摘 要 】

The Idaho National Laboratory (INL) recently provided technical support for ongoing environmental remediation activities at the Shepley???s Hill remediation site near Devens, MA (Figure 1). The technical support was requested as follow-on work to an initial screening level radiation survey conducted in 2008. The purpose of the original study was to assess the efficacy of the INL-developed Backpack Sodium Iodide System (BaSIS) for detecting elevated areas of natural radioactivity due to the decay of radon-222 gases emanating from the underlying fracture sets. Although the results from the initial study were mixed, the BaSIS radiation surveys did confirm that exposed bedrock outcrops have higher natural radioactivity than the surficial soils, thus a high potential for detecting elevated levels of radon and/or radon daughter products. (INL 2009) The short count times associated with the BaSIS measurements limited the ability of the system to respond to elevated levels of radioactivity from a subsurface source, in this instance radon gas emanating from fracture sets. Thus, it was postulated that a different methodology be employed to directly detect the radon in the soil gases. The CR-39 particle track detectors were investigated through an extensive literature and technology search. The relatively long deployment or ???detection??? time of several days, as well as the sensitivity of the measurement and robustness of the detectors made the CR-39 technology promising for deployment at the Shepley???s Hill site.