By Brandon Merano

ROCKTON, Ill. (CBS) — A blanket of foam coating covered what was left of a chemical plant in Rockton, Illinois on Tuesday – a day after a massive fire broke out there.

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As CBS 2’s Brandon Merano reported, a private team from Louisiana came in and used the foam instead of water, because they were concerned about water runoff into the Rock River – which is fewer than 500 yards from the plant. The fire was allowed to go on burning for the same reason on Monday.

The biggest concern Tuesday was the environment, and people’s health. Samples of water from the Rock River did not show any contamination Tuesday, but the Illinois Environmental Protection Agency announced it has discovered a low level of hydrogen cyanide around the plant.

For that reason, Winnebago County Department of Public Health Administrator Dr. Sandra Martell said those within the one-mile evacuation zone would need to remain away from their homes for at least another night. She said air quality numbers have improved, but monitoring must continue.

“We have come this far in suppressing a very difficult fire with a myriad of chemicals, and we want to ensure and assure our population that they are safe to return to their homes,” Martell said.

The fire began around 7 a.m. Monday at the Chemtool plant at 1165 Prairie Hill Rd. Some neighbors in the area reported hearing small explosions as the fire started burning. The company manufactures fluids, lubricants, and grease products for machinery.

A day later, the greatest concerns were the environment and people’s health.

“It’s mind-boggling nobody was hurt,” said Dick Bkork of Belvidere.

On Monday, flames shot out of the building as plumes of black smoke billowed into the air – so massive that they appeared on weather radar and could be seen from as far away as Kankakee.

“I looked out the window making coffee like I said, and it was in flames,” said former Chemtool contractor Jean Norman.

Norman did contract welding for Chemtool.

“We were told it’s safe, it’s OK,” he said, “We wear Tyvek suits, respirators, we have air monitoring equipment, and we’re inside welding.”

On Tuesday, the Chemtool fire looked much tamer than the day before.

“And it’s real close to the river, so that’s why I’m down here to make sure – kind of like ease my mind,” Norman said as he talked to Merano while sitting at a picnic table near the river.

Crews on Tuesday were trying to do the same thing, now using the special foam instead of water to prevent contaminating the Rock River any further.

We found debris from the factory scattered throughout the riverbanks and in the river itself on Tuesday.

“Oh sure, you can probably make out pieces that are pushed up to the powerhouse there,” Bkork said.

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Norman said the chemicals tend to stick around.

“I’ve still got grease in my shower from that place,” he said. “It’s been three years since I’ve been there.”

People who live nearby, like Bkork, are likewise concerned about the Rock River. He was fishing on Tuesday afternoon with debris from the fire in sight.

“It makes you wonder how far that traveled,” he said.

Officials said barriers were put in the river for protection.

Rockton police also confirmed Tuesday that monitoring devices have been set up around the area. Good ground-quality air has been detected and no contaminants have been reported. Water contamination monitoring is ongoing and officials will continue to provide updates.

Meanwhile, a total of 200 employees at the Chemtool pant are now without a job.

“Hard times – oh yeah, I can relate,” Norman said.

The good news on Tuesday was that Chemtool announced all workers will still be paid as cleanup continues.

Officials on Tuesday were still not releasing the official cause of the fire, but they did say they are investigating whether or not the plant’s sprinkler system was working at the time.

“When I was working there, I was like – if this thing ever goes up, well…,” Norman said.

Late Tuesday, crews on the ground were digging in for the long haul. Officials said the fire could burn for seven days.

Beyond the evacuation zone, anyone within a three-mile radius is asked to still wear masks for lung protection.

Public health officials will answer any community question through a new hotline at 815-972-7300 or by email at rocktonchemfire@wchd.org.

Police also confirmed on Tuesday that two people injured in the fire, including a firefighter, have been treated and released from local hospitals.

Also late Tuesday, the Illinois Environmental Protection Agency said the release of pollution from the fire is a violation of the state’s pollution control regulations. They have referred the case to the Illinois Attorney General’s office.

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The CBS 2 Investigators also learned of one open investigation with the Occupational Safety and Health Administration. There were also investigations in 2012 and 2013.

CBS 2 Chicago Staff