Drinking Water Well Receptor Survey, MTBE and BTEX Contamination — Hebron, Connecticut

LEI began a drinking water well receptor survey in Hebron, Connecticut, following the detection of elevated concentrations of MTBE and BTEX compounds in monitoring wells located adjacent to an underground storage tank system.

Working with town staff, LEI identified public water wells and then used Town of Hebron Tax AssessorĂ­s maps to determine those properties located within 500 feet of the subject property. After all properties were identified and addresses verified, property owners were sent certified letters requesting permission to sample. The letters also asked for well completion information and current water treatment systems in use.

Based upon the results of the receptor survey and sampling program, LEI concluded that the well impacts were the result of a gasoline-range hydrocarbon release. The impacted wells are oriented along a linear trend from northeast to southwest through the center of the receptor survey area. LEI recommended multi-stage granulated activated carbon (GAC) treatment systems for three properties to remove volatile organic compounds and MTBE from the raw water, monthly and quarterly sampling of five properties as well as additional re-sampling of six properties during a subsequent dry season.