Delaware Division of Public Health (DPH) staff was surprised to discover unusually high levels of trichloroethylene (TCE) in drinking water at a local Boys and Girls Club last week, and promptly advised Millsboro and Dagsboro town residents to stop drinking the water.
In response, the Delaware National Guard delivered a 400-gallon tanker truck, topped off with clean drinking water, to the Dagsboro Fire Hall (210 Waples St.), on Oct. 26.
Dagsboro Mayor Brad Connor offered a couple reminders:
• The water is free, but the National Guard is providing it for the residents of Millsboro and Dagsboro — people hooked up to the municipal water system, not just random people who didn’t like the way their well water tastes.
• The water is located at the fire hall, but people should try to avoid inundating the volunteer firefighters with calls on the subject.
• People should bring their own containers and can carry away as much as they want, within reason — “but not hundreds of gallons,” Connor stated. No hoarding.
The state has suggested residents use town water sparingly for bathing as well, but DPH Office of Drinking Water’s Ed Hallock (program administrator) said health impacts from short-term exposure were not life-threatening.
“The main concern is to get a treatment system in place and get these contaminants out of the system,” he said.
According to the Environmental Protection Agency (EPA), ”Some people who drink water containing trichloroethylene in excess of the (maximum contaminant level) over many years could experience problems with their liver and may have an increased risk of getting cancer.”
The EPA has set the standard at no more than 5 parts per billion (ppb).
Tracing the problem back to Millsboro’s central water system, Hallock said one of the town wells tapped into a deep, confined aquifer and the quality of that water well exceeded the standard. “The other two wells are in a shallow, unconfined aquifer, and they were heavily impacted, though,” he said. Those wells revealed TCE levels at between 70 and 80 ppb.
Short term health effects can come from exposure but unless people had been drinking a lot of contaminated water over an extended period of time, Haddock suggested there’d likely be no long-term health effects. He said the EPA based its classification of TCE as a possible carcinogen on consumption of 3 liters of water a day, over a 70 year timeframe.
It might be a little while before Millsboro and Dagsboro residents can drink the water again, Hallock pointed out. The towns will need to run the contaminated water through a two-part system, first to aerate it (TCE is highly volatile, so that will get rid of most of it) and then to filter it through activated charcoal to get the rest, he said.
“If they can find a package treatment system that’s available nearby, two weeks is probably doable,” he said. “Otherwise, it might be a month or more.”
In the meantime, Dagsboro Mayor Brad Connor encouraged residents who were hooked into town water to stop by the fire hall.
“Basically, it’s just drinking the water that’s a problem,” Connor reminded. “The contamination isn’t so high that it would do any damage — you’d have to drink it for a long time.”
The DPH had discovered the problem during routine testing, Hallock said, but the Department of Natural Resources and Environmental Control (DNREC) has begun testing public and private wells around Millsboro.