Minergy Pushes Plan to Melt PCB Sediment

Posted Oct. 01, 2003

DNR says process is too expensive for Little Lake Butte des Morts

NEENAH — Minergy Corp. officials are pounding the public speaking circuit, arguing that destroying PCBs is better than burying them.

Minergy’s engineers have proven they can melt PCB-contaminated Fox River sediments in a glass furnace, safely destroying PCBs, dioxins and other organic contaminants while producing an environmentally clean glass aggregate.

Now company officials want Minergy to become a part of the Fox River solution, to become a player in the largest cleanup ever attempted on a North American river.

“We are just going to go out and talk to anyone who will listen to us,” said Wally Kunicki, a vice president for We Energies and its subsidiary, the Minergy Corp. “We think it is a tremendous application for the community and the environment.”

As a late arrival in the cleanup process, they are fighting against time.

Glass furnace technology has already been ruled out as an option for the impending cleanup of Little Lake Butte des Morts, said Bruce Baker, an administrator with the state Department of Natural Resources.

It still has some chance, however, when engineers draw up detailed plans for dredging the vastly larger quantities of contaminated sediments in the lower portions of the river, in De Pere and Green Bay.

The question facing state and federal regulators — and the paper company officials being required to bankroll a cleanup that will cost more than $300 million — is cost.

Terry Carroll, regional manager for Minergy, said the company has already completed cost studies that show the melter to be competitive with landfill costs, especially given the finality of PCB destruction.

Not everyone is a believer. No one has ever built a glass furnace big enough to melt millions of tons of river sediment.

“In my mind, this is new technology,” said Al Toma, regional manager of governmental affairs for Georgia-Pacific Corp. “These melter units, they are big units. You are going to make a large capital investment. If the thing does not work, you have basically thrown away that money.”

Toma said fluctuations in the price of natural gas could drive up the cost of operating a furnace.

Carroll said glass furnaces, unlike incinerators, use relatively small amounts of natural gas, about a tenth the amount used to fire Minergy’s sludge-burning furnace in Neenah. Nor does the scale of the project frighten him. They built the plant in Neenah and came within 1 percent of the projected cost, he said.

Baker said Minergy’s glass furnace technology was rejected for Little Lake Butte des Morts because the offer of landfill space for cost by Georgia-Pacific drives the cost of landfill disposal below any price that Minergy could offer.

In the meantime, the quantity of sediments downstream is almost 10 times greater, as are the stakes.

Baker said agency officials want glass furnace technology to be considered when engineers draw up detailed plans for removing sediments from the lower portions of the river, in De Pere and Green Bay.

This is tricky, however. In order to make reasonable cost comparisons, engineers would have to prepare advanced designs for both the landfill option and the glass furnace. In both cases, water would have to be removed from the slurry vacuumed from the river bottom.

The current DNR plan is to use hydraulic dredges to vacuum a slurry of water and sediment from the river bottom and pump it through a pipeline into southern Brown County where the dense, clay soil makes an ideal substrate for landfills. The plan envisions “passive” dewatering lagoons located next to landfill cells.

Regulators assume dredged sediments would have to undergo more expensive mechanical dewatering to reach the minimum of 30 percent solids required by the glass furnace.

In the minds of some regulators that puts the cost of melting out of reach, but Carroll said the comparison is not fair.

It is possible to use precision dredging techniques to remove the sediment from the river without mixing it with river water, sediments with more than 30 percent solids that could go right into the melter. There are other options, including a dewatering tank that would act like the lagoons in the DNR plan.

Minergy’s technology does have its devotees, among them municipal officials who worry about long-term landfill costs and the potential, no matter how small, for future liability.

The Sierra Club, which fought hard against paper company proposals to cap river sediments in place under layers of clean sand, has always opposed incineration of sediments, because incinerators are notorious polluters. But Sierra Club experts recognize that melting sediments is different than trying to burn them.

“We have always been for permanent destruction of PCBs, and this holds promise,” said Jennifer Feyerherm, a toxics specialist with the Sierra Club. “We need to see more specifics as we proceed.”

Ed Culhane can be reached at 920-993-1000, ext. 216, or by e-mail at eculhane@ postcrescent.com