By Joe Holden

BROOKHAVEN, Pa. (CBS) — Officials say it will take a huge effort to clean up thousands of gallons of gasoline that spilled Friday in Delaware County and was made worse by Monday’s rain.

Delaware County District Attorney Jack Stollsteimer says their investigation at this rate is preliminary. Here are the operating theories. Did something go wrong with the underground tanks and their integrity, or was it how the product was delivered to the site and offloaded?

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Prosecutors say they do have surveillance video and they are reviewing it.

Brookhaven Borough officials say cleanup could take months, and those elected officials say the borough will be made whole.

“As far as their initial cleanup, you’re probably looking at months and again, our concern is really the impact to the residents,” Brookhaven Council President Terry Heller said. “What’s done is done unfortunately with the local wildlife.

Let’s walk through where things stand and how the spill happened.

The leak, overflow or release originated at the gas station on the corner of Edgmont Avenue and Coebourn Boulevard.

Gas funneled down a hill and into a storm drain. It channeled under Coebourn Elementary and filled a retention basin. Most of the greenery will be removed.

The gasoline then continued out a stream and then made it into Chester Creek.

We launched DroneWatch 3 over Chester Creek earlier Tuesday afternoon.

Unlike Monday, when we were finding dead fish, there was no visible evidence of any effect on wildlife, though heavy rain did elevate the creek level, meaning any debris on the banks could have been washed away.

An officer with the state game commission said the effect on wildlife is extensive.

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The gasoline smell is dissipating in this section of Brookhaven, which is a positive direction after several days of anxiety.

Meanwhile, Penn Delco School officials have decided to keep Coebourn Elementary students virtual for the remainder of the school year. Their school is just feet from the gas release.

“The storm management system worked as it was supposed,” Penn Delco School Superintendent George Steinhoff said. “Unfortunately, that system runs all the way around the back of our school and into a retention basin so there really is a large amount of cleanup that still has to happen.”

Neighbors are increasingly frustrated with the effect the gasoline will long have on wildlife in the surrounding woods.

“One of the reasons why we moved here a few years ago is because we liked that there’s still woods even though we’re close to the city,” Allison Wilkins said. “So, it’s really upsetting, are we still going to see a deer in our yard? Are we still going to see the foxes? Is my son still going to be able to catch frogs?”

Emergency officials say much of the fuel exited this retention basin, flowed into a nearby stream, which then empties into Chester Creek.

Levels were running high when we checked on the area with DroneWatch 3.

There was no visible sign of contamination.

Officials are promising an extensive investigation into what has been described as a disaster.

“I will say this, and I will be clear with this. If this was neglect, the borough will be made whole and the residents will be made whole, and right now I believe it to be neglect,” Heller said.

The underground tanks at the gas station were tested Monday for integrity. Those results have not been made public.

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Efforts to reach the gas station owner have been successful.