By Joe Holden

BROOKHAVEN, Pa. (CBS) — In Delaware County, authorities are calling a Friday night gasoline spill an environmental disaster. The scope of the damage is still unknown.

Now authorities are trying to figure out what happened, and whether criminal charges are warranted.

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The big question continues to be how did gasoline leave the gas station property, flow down a hill and then enter a storm drain? The storm drain flows directly under Coebourn Elementary School and flows into a local stream.

The ramifications of a 4,000-gallon gasoline discharge are unknown. It’s too early to estimate how extensive the environmental damage will be.

But fish, fox and raccoon have been killed as a result of the spill.

“What was obviously a small-scale disaster now is gonna go days into remediation, closed school, affected community. And here we are, day three, with a large environmental cleanup,” said Timothy Boyce with Delaware County Emergency Services.

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Officials say the gasoline, enough to entirely fill one vacuum truck, flowed off the property of the Gas N Go at the corner of Edgmont Avenue and Coebourn Boulevard.

The matter is now under investigation by multiple local, state and federal agencies, including a criminal probe launched by the Delaware County District Attorney’s Office.

“We’re here from the DA’s Office because we are concerned. We’re concerned with what happened,” Assistant District Attorney Douglas Rhoads said.

The catastrophic leak forced the closure of Coebourn Elementary, the temporary shutdown of a sewage treatment plant downstream, and will force the excavation of acres of gasoline-soaked wetlands.

“One of the consequences from this not being reported by someone responsible is we’re 8 hours behind in a cleanup and remediation. What could have been a couple hundred yards is now more than a mile,” Boyce said.

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Officials say it would be impossible to contain most of the gasoline and stress the damage is already done.