YAPHANK - Some Long Island environmentalists are concerned about a new study that says drinking and surface waters in Suffolk County are showing an increase in pollution.

The preliminary findings released by the Suffolk County Department of Health Services show the water quality in some underground aquifers has declined since the last report 17 years ago.

Some environment experts say Long Island's sewage treatment plants don't always meet state standards and many small, private wells are registering an increase in pollution.

The local group of environmentalists also says that if Suffolk continues along the same path, the drinking water supply will be undrinkable by 2050.

Environmentalists say there should be an immediate plan in place to reverse the trend. Some are calling for federal and state hearings on the issue.