Sites in Kentucky that require environmental remediation will soon be subject to new, and in some cases more stringent, standards for screening and cleanup. On March 16, 2011, Governor Beshear signed Senate Bill 70 into law, which requires the use of the EPA Region 3 Regional Screening Levels (RSLs) rather than the EPA Region 9 Preliminary Remediation Goals (PRGs) as screening levels for Kentucky's voluntary cleanup programs. The PRGs have served as remediation screening levels in Kentucky since 2001. Senate Bill 70, which goes into effect July 15, 2011, could affect the remediation obligations at a number of sites.
RSLs are used for site screening to identify areas, contaminants, and conditions that require further attention at a particular site, and in some cases are used as cleanup standards. RSLs set forth acceptable concentrations for individual chemicals in the exposure pathways of soil, air and water. RSLs are risk-based, combining exposure information with EPA toxicity data, and are considered by EPA to be protective for humans (including sensitive groups) over a lifetime of exposure. The RSLs are default values that do not take into account site-specific information, and may be recalculated using site-specific data.
EPA Region 3 developed the RSLs to reflect the current science of human health risk assessment. For contaminants in soil on residential property, the RSL is more stringent than the PRG for 87 of the chemicals and less stringent for 163. The residential RSL is the same as the PRG for 290 of the chemicals. For industrial property, the RSL is more stringent than the PRG for 59 of the chemicals and less stringent for 203. The industrial RSL is the same as the PRG for 278 of the chemicals. Additionally, 148 new chemicals have been added to the RSL list that are not present on the PRG list.