Health officials eye private Brookhaven hamlet wells


Suffolk health officials are knocking on doors in Brookhaven hamlet, telling residents with private wells to have them tested for traces of a plume that originated decades earlier at the town landfill.

First discovered in 1980, the problem is believed to stem from failed landfill liners that released leachate, water that percolates through landfilled trash, into local groundwater. The plume contains ammonia and volatile organic chemicals such as chlorobenzene, an ingredient in some pesticides, and tetrachloroethylene (PCE), used in dry cleaning, according to town monitoring reports.

Water samples from Beaver Dam Creek and an irrigation well at the Hamlet Organic Garden indicate the plume has traveled southeast and is moving toward the Carmans River. Brookhaven officials said they were taking steps to map the extent of the plume, which has not been done since the 1980s.

While the contamination doesn't appear to exceed drinking water standards, some fear the ammonia could harm brook trout and other marine life. "It's very toxic to fish," said Robert Waters, supervisor of the Suffolk health department's marine bureau.

No drinking water standards have been set for ammonia and no health effects have been found in humans exposed to typical environmental concentrations, according to the federal Agency for Toxic Substances and Disease Registry.

Some residents were taken aback by the news of the contamination, made public this summer in a county report on water quality in Beaver Dam Creek. Others who already knew about the plume said more should have been done to track its progress.

"It is something that was known many years, and there was a study that pointed out where it was going to go," said Thomas Williams, vice president of the Post-Morrow Foundation, an organization dedicated to preserving the character of Brookhaven hamlet. The county did the water quality study at the group's behest.

The portions of the landfill where the leaks were thought to originate were capped in the 1990s to prevent more water getting in. Contamination concentrations closest to the source have since declined, town officials said.

"Eventually the leak will be cut off completely," said Ed Hubbard, Brookhaven's commissioner of waste management. "It's a 260-foot waste mass, so it's going to take some time to drain out."

The state Department of Environmental Conservation did not require further remediation because the plume not classified as hazardous waste, DEC spokesman Bill Fonda said.

The town has monitored groundwater at the landfill for years and also tested Beaver Dam Creek for traces of the contamination. Public water was extended to neighborhoods below the landfill in the late 1980s, but some property owners may not have chosen to connect at that time.

Manager Sean Pilger had both wells at the organic garden, known as the Hog Farm, tested for a wider range of contaminants than usual this year after learning of the plume's progress. Chemicals matching those in the landfill plume showed up in the farm's north well, although levels were still within drinking water standards. Pilger said the farm is drilling a deeper well to bypass the contamination.

Officials are investigating 51 properties in the potential path of the plume that may still use well water. About one-third have already been determined to be on public water and test results from six wells are pending.

The DEC will conduct a survey of Beaver Dam Creek next year to determine whether the plume has affected brook trout or other marine life.