RA-3823_23187_CA_HRE_20210617_new1

June 17, 2021 TO: Craig McIntosh
Raleigh Regional Office
NC UST Section RE: Health Risk Evaluation Incident # 23187
Tilley Well Sampling Results (Before filter)
1502 Bahama Road Bahama, NC During this sampling event, two contaminants were detected in the well water. The standards used to
determine if the water is suitable for drinking and cooking are the United States Environmental Protection
Agency’s Maximum Contaminant Levels (MCLs) or, if no MCLs exist, North Carolina Groundwater Standards (2L). If any contaminant concentrations exceed applicable standards for using the water for drinking and
cooking, those contaminant concentrations are further analyzed to determine if the water is suitable for other
household uses, such as showering, bathing, washing dishes, flushing toilets, and hand washing. The chart below compares the detected contaminant concentrations with the applicable standards: Sample ID Contaminant Concentration (µg/L) MCL (µg/L) 2L (µg/L)
CE06254-01 Isopropyl Ether 110 70
Methyl-tert-Butyl Ether 1,400 20
Shaded boxes indicate a standard has been exceeded.
µg/L – Stands for micrograms of contaminant per liter of water and is roughly equivalent to parts per billion.
RECOMMENDATION: The isopropyl ether and methyl-tert-butyl ether concentrations exceed the applicable standards and the level that would be considered safe for other household uses. Therefore, this water
is not recommended for any residential use at this time.

David Lilley, Environmental Toxicologist
Division of Waste Management, NCDEQ