Pollution investigators probe for clues solutions

The car pulls up and the investigators get out, pop the trunk, remove their equipment. They pull on gloves, then dip under the yellow tape strung around the property. Expressionless, they scan the ground for subtle clues. There's not much in the area leading up to building; the best evidence may be inside.

These investigators aren't police detectives, they're scientists from The Johnson Company, looking for evidence of pollution.

There are 60 such firms in Vermont, and they play a key role in keeping our environment healthy. Their work also assures that real estate development, at the least, does not damage ecosystems, and ideally results in cleaning up poisons that have lingered for decades.

Chris Crandell, owner of The Johnson Company, is tall, lanky, and though he was born in Colorado, he speaks in an understated way reminiscent of the old-school Yankee reserve of Sen. James Jeffords.

Based in Montpelier, his company is among Vermont's foremost pollution remediation firms. Its staff of 25 is trained in all the diverse fields necessary: chemistry, toxicology, geology, hydrology, ecology, microbiology, mechanical engineering. Their investigations may not have the jaw-clenching suspense of a "CSI" episode, but the stakes can be high.

The Lower Fox River case demonstrates the scope and complexity of some of these problems. Remember the carbonless copy paper that became popular just before the photocopying era? When the market for it vanished, the Wisconsin-based manufacturer recycled trainloads of remainders, rinsing out the pigmenting chemicals and reprocessing the pulp into new paper.

But its copying trick relied on microscopic capsules of PCB, a highly dangerous carcinogen. When the rinse water was discharged, huge quantities of PCBs went into the Lower Fox River. The result was 40 miles of toxic riverbed.

Assessing the problem was just the start. Then The Johnson Company had to design a cleanup plan for millions of tons of contaminated silt. Leave it, and it keeps poisoning things and waits like a time bomb that could go off in a flood; try to remove it and you disturb the silt, circulating the poison through the ecosystem again. A devilish challenge.

Simpler, and smaller, the Pyralisk Arts Center property in Montpelier is more representative of Vermont's pollution problems. The Johnson team began its work on the old rail yard site with a Phase 1 assessment, searching historical records to find prior uses likely to pollute, finding no indication of any.

But the terms of a federal grant required a Phase 2 investigation. So the Johnson team drilled holes, sniffed the holes with photo-ionization devices (PIDs), and took soil samples.

PAH) concentrations above regulations. PAHs are low-level carcinogens, resulting from combustion of materials such as the diesel fuel used by railroad locomotives.

The Johnson Company drilled more holes in a grid pattern throughout the property and inside the building, testing dozens of samples. One turned up PCBs, a piece of an electrical transformer, deep below the building's floor.

So the property became an official "brownfield" site. Working with the Central Vermont Planning Commission and the Department of Environmental Conservation, The Johnson Company developed a plan to remove and cap contaminated soils.

Water and soil samples are run through an analytical gauntlet of high-tech processes such as X-ray fluorescence to detect metals, and immunoassays that use enzymes that react to certain chemicals. Gas chromatographs and mass spectrometers can comprehensively identify mineral and chemical content.

For larger jobs, a staffer logs data into a computer program that maps contaminant location and concentration. Modeled in 3-D and vivid colors, the portrait of a pollutant "plume" is a startling and menacing image, resembling the underwater part of an iceberg.

Remediation plans can range from simply covering the ground with grass, to removing tons of soil to controlled dump sites, to highly complex underground or underwater containment or aeration systems. Pumping liquids or venting volatiles can take decades.

Again, new technologies help. Several, including microwave bombardment, heat soil deep below the surface, rendering toxins harmless.

Working throughout the U.S. and abroad, Chris Crandell has acquired a good perspective on the state of pollution.

How clean is Vermont? "Quite clean, relative to most other states," he says. He adds, with irony, "But we're not in any danger of running out of work."

The Department of Environmental Conservation lists 1,555 known brownfields sites, and thousands more are out there. They're in most Vermont towns, in industrial sites as well as town halls, churches, campgrounds, parks, schools, playgrounds, fire stations, farms, residences.

We'll be needing those vigilant detectives, the unsung heroes of the ESES sector, for a long time to come.

For information about contaminated sites in your area, visit: www.anr.state.vt.us/dec/wastediv/SMS/hazsites.

Additional information :

From www.timesargus.com:
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