Fire crews are still on the scene of a major fire that destroyed a recycling plant in Jersey City.

The crews worked to extinguish hotspots that were buried 15 feet deep in mountains of paper and cardboard at Reliable Paper Recycling.

Employees at the company have been using heavy machinery to pull out large bales of paper and cardboard. The bales need to be separated to expose heat and flames and then soaked with water cannons.

This process has been going on since the fire was placed under control Tuesday night. Officials say that it is a process that could take several more hours.

“It’s windy. It’s dry. We want to make sure there aren’t any hotspots in there to have this thing rekindle,” says Greg Kierce, director of Jersey City Emergency Management.

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Reliable Paper Recycling has been in Jersey City for 35 years. It is a recycling operation that serves New Jersey and New York. It runs around the clock.

The company has 65 employees – most of whom are now out of a job. The building was badly damaged and what is left will need to be torn down.

News 12 New Jersey is told several agencies have been on site trying to figure the cause of the fire.

One of the agencies is the Bureau of Alcohol, Tobacco, Firearms and Explosives. Kierce says ATF hopes to get help from surveillance cameras.

“There were video cameras on the building. So, they’ll pull the available video and then go frame by frame and see if anything jumps out,” he says.

The fire did cause some New Jersey Transit Light Rail services to be suspended. The Jersey City Fire Department gave the all-clear for service to resume earlier Wednesday morning.