By Kim Glovas

PHILADELPHIA (CBS) — Sunoco’s controversial Mariner East 2 Pipeline is under construction, but a coalition of residents wants to make sure proper plans are in effect in case the pipeline leaks.

Private wells have already been contaminated by the project.

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Eric Friedman is with the Middletown Coalition for Consumer Safety. He says water contamination could have been avoided.

“These risks to public and private water supplies were thoroughly well documented in advance, at a number of different places, including in Sunoco’s own documents provided to the Department of Environmental Protection,” Friedman said.

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He says if the liquid gases in the pipeline are leaked, it could be disastrous.

“They return to a gaseous phase and these gases are colorless and odorless, extremely flammable, and also heavier than air, so they don’t tend to disperse. They actually tend to concentrate close to the ground. And in a densely populated area like Southeast Pennsylvania, there are plenty of potential ignition sources,” said Friedman.

Meanwhile, the Clean Air Council is suing Sunoco on grounds that Mariner East 2 violates federal and state constitutions.

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The case could be heard later this year.