From the "TESTIMONY OF STAN MEIBURG
ACTING REGIONAL ADMINISTRATOR, REGION 4
U.S. ENVIRONMENTAL PROTECTION AGENCY
COMMITTEE ON TRANSPORTATION AND INFRASTRUCTURE
SUBCOMMITTEE ON WATER RESOURCES AND THE ENVIRONMENT
March 31, 2009"
(link...)
"In the aftermath of the incident, EPA sampled the coal ash and residential soil to determine if the release posed an immediate threat to human health. Sampling results for coal ash contaminated residential soil showed arsenic, cobalt, iron, and thallium levels above the residential Superfund soil screening values. Sampling results also showed average arsenic levels in the Kingston coal ash and coal ash contaminated residential soil above the EPA Region 4 Residential Removal Action Levels (RALs). RALs are used to trigger TIME-CRITICAL REMOVAL actions while soil screening values, are used as a point of departure for EPA to take any action to investigate and/or remediate a release. In response to exceedances of RALs for ash contaminated residential soils, TVA relocated RESIDENTS TO INTERRUPT THIS SOIL EXPOSURE PATHWAY. "