A chemical linked to health concerns including impaired fetal growth and some cancers has been detected in 45 private wells in East Quogue, Southampton Town and Suffolk County officials reported.
Two of the wells tested positive for perfluorooctanesulfonic, known as PFOS, at levels higher than the federal health advisory level. Forty-three wells tested positive for the compound, but at concentrations below the limit, the data show.
The testing started after officials announced in April that a monitoring well drilled near a former landfill on Damascus Road detected PFOS in a concentration more than 150 times the level at which federal officials say exposure in drinking water can cause health problems. The town has since provided bottled water to nearby residents.
The two highest-level wells had readings of 344 and 220 parts per trillion, according to the town. The federal health advisory sets a standard at 70 parts per trillion. A part per trillion is the measurement of the quantity of a substance in the water for every one trillion parts of water.
The U.S. Department of Health and Human Services last month released a draft report stating the chemical can be harmful to human health at lower levels than the Environmental Protection Agency’s health advisory level of 70 parts per trillion.
Suffolk County's survey area tested 118 wells serving 117 properties. Other than the two wells with the high levels, 43 wells had the chemical in concentrations below the federal advisory limit, officials reported, and tests of others did not detect any PFOS readings. Twenty-two property owners did not respond and samples still need to be collected for the remaining five wells, officials said.
The town is working with the Suffolk County Water Authority to determine the cost of connecting the affected properties to public water.
"We are addressing it in an agressive way," said Southampton Town Deputy Supervisor Frank Zappone.
The state Department of Environmental Conservation has since installed treatment systems at three properties, according to an agency spokeswoman.
The DEC monitoring well was one of three drilled near the 10.6-acre former landfill in January as part of a broader state investigation into how pollution from closed landfills affects groundwater. Tests in February at the well drilled south of the landfill revealed PFOS levels at 11,200 parts per trillion.
The DEC has directed the town to undertake an environmental investigation to identify potential sources of the contamination and determine if the contamination poses a significant health threat.
Southampton Town is to hire an environmental consulting firm to investigate the property. The board voted 5-0 at its July 10 meeting to enter a $19,040 contract with Amec E & E, which has an office in Bayside, Queens, for Phase I of the work, which includes resampling wells and looking for possible contamination sources. That work has already begun and a report is expected some time in August, Zappone said.
Phase II, which will include a survey for a possible water table map, will be part of a separate contract.