Regulations incorporating background values: Can compliance be verified?

Federal regulatory agencies, specifically the U.S. Environmental Protection Agency (EPA) and the U.S. Nuclear Regulatory Commission (NRC), have promulgated and continue to propose regulatory standards for remediation and decommissioning activities that approach the levels of naturally occurring background quantities. The most recent proposals by both EPA and NRC are the radiological cleanup standards of 15 mrem/yr above the natural background of a particular site for residual radioactivity remaining at the completion of remediation. This paper discusses the results of a radiological background determination for a typical remediation site and provides a summary of the way that variations in this natural background affect the verification efforts to demonstrate that the cleanup criteria have been satisfied