RA-2181_13379_CA_HRE_20230427_Determination WSW 2 Arvin

April 27, 2023
TO: Mark Petermann NC UST Section RE: Health Risk Evaluation
Incident # 13379 James Arvin Well Sampling Results 5837 Fayetteville Road Raleigh, NC

During this sampling event, four 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 contaminant concentrations exceed the applicable standards for using the water for drinking and cooking, the contaminant concentrations are further analyzed to determine if the water is suitable for other non-ingestive 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)
91750 Methyl tert-butyl-ether 46.4 20
1,2-Dichloroethane 2.78 5
Di-Isopropyl Ether 1.18 70
Benzene 10.5 5
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 methyl-tert-butyl ether and benzene concentrations in this well exceed the applicable standards. Therefore, this water is not recommended for drinking or cooking at this time. No restrictions are recommended for using the water for other non-ingestive uses, such as
showering, bathing, washing dishes, flushing toilets, and hand washing.

David Lilley, Environmental Toxicologist
Division of Waste Management, NCDEQ