MO-6015_23108_G_WSW_20230824_HELDERMANHRE

August 24, 2023 Gypsi Helderman
P.O. Box 541 Alexis, North Carolina 28006
Re: Health Risk Evaluation of Water Supply Tracking ID: Inc. No. 23108 Dear Ms. Helderman: Please find attached the Sample Analytical Results for water samples collected before the Point-of-Entry system on your well, identified as WS-5 Before and WS-5After, located at 115 Alexis-Lucia Road, Alexis, Gaston County, on August 2, 2023. The samples were collected and analyzed as part of the investigation of a petroleum release in the vicinity. The water samples were analyzed for specific target analytes (contaminants), which are listed on the attached Sample Analytical Results. Contaminants were detected in the before water sample, as shown on the attached Sample Analytical Results. No
contaminants were detected above the laboratory’s method detection limit in the after samples. Because contaminants were detected in the water sample, a Health Risk Evaluation of each water
supply sample was performed by an environmental toxicologist in the Division of Waste Management. The Health Risk Evaluation, which is attached also, compares the detected concentration of contaminants to acceptable concentrations and provides a recommendation for safe use of the water.
If you have any questions, please contact David Lilley at [phone] or contact me at [phone]. Sincerely, Brad C. Newton, P.G. Hydrogeologist
Mooresville Regional Office UST Section, Division of Waste Management, NCDEQ
Attachments: Helderman Sample Analytical Results Health Risk Evaluation
cc: Gaston County Health Department Gaston County Manager

August 23, 2023
TO: Brad Newton Mooresville Regional Office
NC UST Section
RE: Health Risk Evaluation Incident # 23108 Gypsi Helderman Well Sampling Results
115 Alexis-Lucia Road
Alexis, 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 household uses, such as showering, bathing, washing dishes, flushing toilets, and hand washing.
The chart below compares the detected contaminant concentrations with the applicable standard:

Sample ID Contaminant Concentration (µg/L) MCL (µg/L) 2L (µg/L)
YH03077-005 Benzene 6.4 5
1,2-Dichloroethane 21 5
Diisopropyl ether 5.6 70
Methyl tertiary butyl ether 51 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 benzene, 1,2-dichloroethane, and methyl tertiary 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