The state Department of Environmental Conservation will oversee the installation of a water treatment system at a building that houses Shelter Island’s senior center and a pair of medical offices after a banned gasoline additive was detected above allowable levels in the property’s private well last month.
Methyl tertiary butyl ether, or MTBE, was found at the South Ferry Road site following a routine test by the Suffolk County Department of Health Services, according to town and county officials.
A review of DEC samples showed the water at the site contained 13 parts per billion, which was slightly higher than the county’s readings and is above the state advisory level of 10 parts per billion.
“The results of DEC’s review will determine if additional treatment systems are necessary and if additional investigation is needed to identify the source and extent of contamination,” a DEC spokeswoman said in a statement.
The town will work with the DEC to determine if further testing is needed, according Shelter Island engineer John Cronin.
The gas-blending compound is not regulated by the federal Environmental Protection Agency, but New York banned its use in 2004 and set the safe drinking water concentration at 10 parts per billion. Previous samples from the senior center showed MTBE at 10 parts per billion on May 16 and 12 parts per billion on May 21, according to a spokeswoman for the county health department
MTBE was first detected at the site at 5 parts per billion in 2010, according to the county health department.
Studies indicate short-term exposure to MTBE is not highly toxic to humans, but many find the odor and taste disagreeable, according to a county notice posted by the town. Longer exposure can cause headaches, nausea, dizziness, irritation of the eyes, ears and throat, and confusion.
Residents are asked to avoid drinking the water at the center. Bottled water will be provided.