The USGS/EPA radon potential of the U. S. '' project: A case study in the application of geoscience information to public policy

As part of an interagency agreement with the US Environmental Protection Agency (EPA), the US Geological Survey (USGS) has prepared a series of maps and reports, by state, describing and assessing the geologic radon potential of the United States. The documents were prepared with multiple uses in mind, including guidance for targeted radon sampling or information programs, to aid in the application of radon-resistant building codes, and as a starting point for more detailed investigations. The USGS and EPA were assisted in the planning and review stages by the Association of American State Geologists, and the draft reports were also reviewed by the state radon contact agencies (typically health departments or departments of environmental protection) and other state and federal agencies. A relative radon potential ranking scheme was developed by USGS to provide consistency and accountability. The scheme consists of a Radon Index, the sum of 5 individually-scored factors (geology, soil permeability, aerial radioactivity, architecture, and screening indoor radon data), and an associated Confidence Index, an expression of the quality and quantity of the data used to evaluate each factor. The assessments are presented on a scale that is useful for state- or regional-scale planning, but inapplicable to areas smallermore » than counties. The most common problems cited by the reviewers are: (1) the conflict of natural geologic boundaries and political boundaries; (2) the use of the NURE aerial radiometric data; (3) the use of short-term charcoal canister data as opposed to long-term annual average data; (4) the definition of high'' radon and the cost of dealing with the radon problem if high'' is 4 pCi/L; and (5) the potential misuse of geologic assessments by the public, the radon industry, and governments. The use of geological common sense in concert with policy decisions can alleviate many of the above problems.« less