MANORVILLE, N.Y. (CBSNewYork) – Contaminants found near mulch and compost facilities on Long Island are raising concerns about the safety of groundwater.

The Suffolk County Health Department studied 11 sites that compost vegetation and discovered manganese, heavy metals, ammonia and arsenic leaching into groundwater near the huge facilities. The levels of heavy metals were as high as 160 times what is considered safe.

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Too much manganese is linked to Parkinson’s disease and neurological problems. Forty thousand families drink from the private wells in Suffolk County.

“We see what’s going on with Flint, Michigan,” said Roy Vaselovic, of Yaphank. “So you wouldn’t want something like that to happen.”

Assemblyman Steve Englebright has been fighting for compost regulation.

“Composting was thought to be entirely wholesome, and on a backyard scale, it is,” he said. “But we are talking about really big facilities. In most cases, they don’t have liners under them.”

The Suffolk Health Department recommends the New York State Department of Environmental Conservation move to strictly regulate mulch facilities and evaluate any potential impact to groundwater before such places are allowed to operate.

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“We want composting to continue,” said Harry Somma of the Citizens Campaign for the Environment. “And this is something that can be handled with new regulations. ”

The DEC said it is listening and will soon require:
• Managing runoff
• Installing monitoring wells
• Testing ground and surface water.

The state plans to release its new draft regulations for compost sites at the end of the month, WCBS 880’s Sophia Hall reports.

While groundwater is the source of Long Island’s drinking water, the report says no well fields that supply drinking water to the public are imminently threatened.

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“People should not be panicking,” said Ty Fuller of the Suffolk Water Authority. “For one, our wells are located at a depth where the impact from that composting facility would not be a cause for concern for us.”