MADAWASKA – Environmental workers continued to change the fiber cloths on booms in the St. John River on Tuesday, still cleaning up a waste-oil spill that occurred Saturday night into Sunday morning.

An oils and hazardous materials specialist from the Maine Department of Environmental Protection said overnight rain caused the St. John River to rise by 1 foot. Runoff from storm drains brought more oil from the storm water outlet above the international bridge from which the spill originated.

The DEP’s Carl Allen said the effort would last two more days.

Meanwhile, workers from the DEP and Clean Harbors Environmental Specialists Inc. of Bangor were changing cloths on booms every two hours Tuesday.

Allen said another 15 to 20 gallons of waste oil and fuel oil had been collected since about 100 gallons were vacuumed off the water Sunday.

The spill, from a waste-oil and fuel-oil tank in the cellar of Larry’s One Stop at 198 East Main St. at Madawaska, was reported by employees of Fraser Paper Inc. at about 9 a.m. Sunday. By Sunday afternoon, an oil sheen was spotted as far west as Grand Isle, eight to 10 miles downriver.

The spill, estimated at more than 150 gallons, was holding to the south shore of the St. John River.

“We are actually starting to gear down,” Allen said Tuesday afternoon. “There is still some [oil] coming from catch basin, but we have that contained at the outfall.

“The residue coming from the outfall does not have much significance,” he said. “I’ve been downriver about 12 miles … and we find blotches of oil all over the place.”

He said the blotches of oil probably were caused by rising water taking residue oil off riverbank gravel and grass and changed the logistics of their work.

In some areas of the river, a sheen of oil can be seen going by.

Allen said he would be turning his report over the agency’s enforcement arm by the end of the week. He said it would decide whether enforcement action is needed.

Allen said a big part of the effort is keeping the oil out of an intake pipe at Fraser Paper Inc. at Madawaska. While the filtration plant has a large filtration system, booms are keeping the oil sheen from entering the intake.

Workers have installed nearly 2,000 feet of booms to contain and gather the oil.

Allen said the town was fortunate because the outfall where the oil entered the St. John River is located downriver from a municipal water supply intake.