Health officials were back in Manorville Wednesday to test the groundwater after a banned chemical was found in a woman's well last week.

As News 12 Long Island has reported, the Suffolk County Health Department found more than 100 parts per billion of MTBE, a gasoline additive that was banned back in 2002, in Clare Bennett's well water.

She and her husband decided to get their well water tested in November after living in Manorville for the past 20 years.

According to the state Department of Environmental Conservation, at least two more private wells on Oakwood Drive have tested positive for MTBE contamination.

Test results revealed one home had levels 10 times higher than the amount acceptable by the state. Another home had 25 times the acceptable amount.

"This is bad. This is very bad," says Clark Nungesser, who has lived on the block for 30 years.

The DEC told News 12 that it is "aggressively conducting an investigation to quickly identify the source and extent of the MTBE contamination and address it in order to protect the public and the environment."

So far, samples have been taken from 13 homes in the area. Homeowners from the two that tested above state standards told News 12 that they are now waiting for the DEC to get proposals from contractors to install treatment systems.

More test results from homes are expected at the end of the week.