Stonington ― More than 50 residents turned out for a Planning and Zoning Commission public hearing Tuesday with many opposing plans for a 113-unit affordable housing project on the former site of Rosalini’s nightclub on Route 2.

Opposition to the proposal by Fair Housing LLC involved concerns about density, traffic, lack of green space, safety and the potential impact on public drinking water supplies.

“Where’s the common sense? There is none. This development is a catastrophe waiting to happen,” resident Nick Verzillo told the commission.

The 4.2-acre Liberty Street property, owned by Misquamicut business owner Eugene Arganese, principal of Fair Housing, sits directly on top of a sole source aquifer that provides drinking water for residents of Pawcatuck and Westerly.

A sole source aquifer is an Environmental Protection Agency designation for a source of water in an area that has no other reasonable source of drinking water should the aquifer become contaminated.

“I support housing that is affordable, but I do not support this project as proposed,” Selectwoman Deborah Downie, a licensed environmental professional with a master’s degree in hydrogeology and 35 years of experience in the field, told the commission.

Downie specified that she was not speaking on behalf of the Board of Selectmen, but as a resident and an expert in her field and said that the aquifer provides 50% of the drinking water for Westerly and Pawcatuck and 70% of the Westerly Water Company’s water supply.

She said that the proposed development sits just 1,600 feet from a groundwater reservoir, an area containing the highest possible yield of drinking water, a recharge area, and a wellhead protection area. She explained that wellhead protection areas are a part of an aquifer that groundwater moves through to a well.

She pointed out the lack of space in the proposed development to allow water to drain into the ground and filter contaminants. She said this deficiency would not only be detrimental to the aquifer but pose a risk of aquifer contamination by heavy metals and hydrocarbons from storm water as it runs off the roofs and concrete that cover nearly all of the site.

She said the proposed stormwater treatment plan was inadequate, testing of the site was insufficient and costs for expensive maintenance, inspection and cleaning of the system would fall to the homeowners’ association.

Resident and attorney Thomas Geroulo applauded Downie’s explanation of the dangers to the aquifer.

“She just gave you a master class in how you’re going to have a glass of cadmium for breakfast,” he said.

Geroulo also suggested the town could expose itself to class action suits from the 12 towns in two states served by the aquifer if it becomes contaminated, adding the commission could reject the proposal on public health and safety grounds.

Under state law, affordable housing proposals can only be rejected if they pose a specific risk to public health or safety, and the risk is not outweighed by the need for affordable housing.

Geroulo cited a 1999 case in which courts sided with the town of Newtown after it rejected a proposed 94-unit affordable housing development on the only other single source aquifer in the state, saying that protecting the aquifer and drinking water outweighed the need for affordable housing.

Residents also opposed the lack of green space in the densely packed development.

Joshua Wheeler, the landscape architect for the project, identified a single potential area for recreation in the northeast corner of the development, measuring less than 200 square feet.

“The size of this is just insane,” resident Julie McNeill said of the 113, 3-bedroom, 2.5-bathroom, attached single family homes, clustered in 11 groups ranging from 3 attached units up to 20.

Pawcatuck residents have been critical of new affordable housing projects proposed for the village such as the downtown Campbell Grain site, saying their section of town already hosts the majority of the town’s affordable units.

The majority of units would be sold at market value, but 30% of the units will be affordable to people who earn 80% or less of the area median income.

For a single individual, 80% of median income is $63,000 per year. The cost to buyers at 60% and 80% of median income would be $191,000 and $280,000, respectively. There was no price given for market-rate units.

The commission voted to continue the hearing to its Dec. 19 meeting when representatives of the project will respond to concerns raised at the hearing.