National cost implications of a perchlorate regulation

Abstract

Compared with other drinking water regulatory determinations, the cost implications of a perchlorate maximum contaminant level are relatively low because of the chemical's limited occurrence in source waters in the United States. However, a small number of systems are carrying this cost burden and the cost implications to an individual system having to install perchlorate treatment would likely be significant. Several studies have evaluated the nationwide occurrence of perchlorate in drinking water sources, but to the authors’ knowledge, no study has been conducted evaluating the cost implications for treatment of all perchlorate‐contaminated drinking water sources. This study was undertaken to bridge this information gap in anticipation of discussions about whether to regulate perchlorate at a national level. If the perchlorate regulation is revisited by the U.S. Environmental Protection Agency, this study is expected to be a key building block for subsequent evaluation of the cost implications of a national perchlorate standard. This article provides an initial estimate of costs associated with such a standard. Details can be used as guidelines for water suppliers as they assess the cost implications of installing perchlorate treatment at their utility.