One of the more challenging issues for companies dealing with contaminated groundwater sites near public drinking water supplies is how to handle contaminants for which there are uncertain or evolving regulatory action levels. For example, perfluorinated chemicals (“PFCs”) have garnered a lot of publicity recently after these contaminants were detected in several municipal drinking water supplies. However, there currently is no federal maximum contaminant level (“MCL”) for PFCs generally, and more specifically, for perfluorooctanoic acid (“PFOA”). Instead, there are conflicting health advisory levels that vary drastically between U.S. EPA and the individual states, ranging between 20 and 400 parts per trillion (“PPT”). Similarly, 1,4-dioxane is another contaminant that is the subject of conflicting regulatory standards in drinking water. There is no MCL for 1,4-dioxane but it, along with PFOA, is on U.S. EPA’s Drinking Water Contaminant Candidate List 4. As such, if detected, the municipality is required to provide notification to the public via its Consumer Confidence Report. However, the health advisory and/or clean-up level for 1,4-dioxane in groundwater varies greatly from state to state, ranging from .3 to 5 parts per billion, and as such, there is no consistent regulatory standard for 1,4-dioxane in drinking water.

Moreover, since these are generally considered to be emerging contaminants with health advisory levels and/or other regulatory standards in the PPT range, there are often issues with respect to a laboratory’s ability to analyze for these contaminants at these extremely low levels. These issues are compounded when these samples need to be analyzed by laboratories accredited under State drinking water programs as often there may only be a single accredited laboratory in a particular state.

The result of these inconsistent regulatory approaches is a patchwork of different requirements depending on the location of the impacted site. Companies that are dealing with sites impacted by these emerging contaminants should be cognizant of the evolving nature of this regulatory framework, and care should be taken to ensure that the treatment methodologies that are being employed will achieve a cleanup level that is appropriately protective of human health so as to mitigate against potential future remedial and/or toxic tort claims.