GEORGETOWN — The town’s public water supply remains under the microscope amid ongoing efforts to determine migration and a possible source of volatile organic compounds.
Delaware’s Department of Natural Resources and Environmental Control recently made a limited site-access request to the town of Georgetown to install temporary sampling points and/or permanent monitoring wells on town-owned property during an expanded site-inspection investigation, according to DNREC Media Relations Manager Michael Globetti.
These inspections and samplings will be made in an effort to determine the direction from which tetrachloroethylene (PCE) is migrating in the groundwater, Georgetown Town Manager Eugene Dvornick announced at a Town Council meeting Wednesday.
“Accordingly, they will be installing temporary wellpoints on the King Street water plant property and conduct multilevel groundwater sampling,” Mr. Dvornick said.
The results from this will determine if a permanent monitoring well should be installed.
As requested by DNREC, “a limited site-access agreement has been executed for this work to be completed,” Mr. Dvornick said.
Repeated periodic detections of volatile organic compounds, including tetrachloroethylene, above the Environmental Protection Agency’s maximum contaminant levels have been found at Georgetown’s public wells since the mid-1980s, Mr. Globetti said.
Georgetown is currently served by two water plants — King Street and South Railroad Avenue.
“When we fire up our wells, it pulls water from all different layers in the aquifer to where the well is, and then, it pumps it up,” Mr. Dvornick said Friday. “That is why they are putting in the monitoring well. They know where the plume is, and they are seeing how much of it gets pulled to the Georgetown water plant.”
However, there is no cause for alarm. Water-treatment systems have been in place to make water safe for Georgetown residents to drink since the high levels were detected, Mr. Globetti said.
Mr. Dvornick said that, several years ago, the state “reduced its limits for PCE, (trichloroethylene) and vinyl chloride, which are all three VOCs that are present in the water at the King Street plant, due to environmental issues, not at the plant but off-site.”
“So as part of that, the state helped us, and we put in brand-new air strippers, which are two, like silos, next to the water plant, … so that water does meet the state standard for drinkability,” Mr. Dvornick said. “It’s not something that is new.”
Over the years, DNREC has identified multiple potential chlorinated solvent and petroleum sources for the VOCs. For example, PCE is a solvent widely used in dry cleaning.
Recently, through EPA grants, DNREC has continued to systematically identify possible origins, conducting sampling to try to determine the sources that are impacting the town’s wells, Mr. Globetti said.
In 2019, DNREC began a preliminary assessment of the Georgetown North Groundwater Plume, followed by a site inspection at the plume in 2020, but sampling failed to identify any new potential sources.
This year, DNREC will conduct an expanded site inspection centered around the Georgetown public wells. Temporary groundwater well sampling points and/or permanent monitoring wells will be installed in a radial pattern surrounding the town’s public wells.
By collecting data, DNREC hopes to determine the direction that the contamination is migrating from, then trace the contamination back to its source or sources, Mr. Globetti said.
Additionally, the town is in the process of working with Sussex County “to do a connection with their water at the airport, so that if they have an issue and they need water, Georgetown can supply the airport and vice versa,” he added.