Report finds groundwater contamination in 35 metro communities

October 2007

U.S. Water News Online

MINNEAPOLIS -- A Star Tribune examination of groundwater monitoring reports found 20 plumes of contaminated groundwater affecting parts of 35 metro-area communities -- despite the more than $200 million that has been spent over two decades to try to combat the problem.

The pollution, mostly from previous industrial dumping, affects communities from Edina to New Brighton to Woodbury. In Washington County, underground pollution seems to be worse than anyone thought.

Altogether, the contaminated areas would equal an area 21/2 times the size of Minneapolis.

No illnesses have been directly linked to the problem, but often, the cleanup seems endless

At 15 locations, special wells have been filtering pollutants from groundwater for decades. In other places, regulators hope soil bacteria will render the chemicals harmless. It could take a century or longer for one plume of pollution beneath St. Louis Park to be flushed clean.

"It is almost like when you throw dye into a jar of water," said Michael Convery, a supervisor in the Health Department's well management section. "It is hard to get it back again. It just spreads out."

According to maps issued by the state Health Department in July, low levels of the 3M chemical PFBA exist in groundwater beneath 99 square miles of Washington County. In a third of that area, levels of the chemical once used for coating photographic film are above what the state advises for drinking water.

Other industries have created plumes of contaminated groundwater elsewhere.

Jim Altier, who built a house outside Bayport more than three decades ago, said his well is polluted with an industrial solvent. He and his family drank the water for 14 years, but he now has an activated-carbon filter, like many other Baytown Township residents.

"I had mixed feelings about it," said Altier, a retired Air National Guard mechanic who worked around solvents. "... I feel better that the filter system is in there."

He still wonders if the chemical, TCE, affected his first wife, Teddie, who died of leukemia in 1997. State health officials have reported no cancer clusters in Washington County.

More than 1.8 million metro residents get tap water from the ground. Suburbs are seeing a disproportionate share of major groundwater chemical plumes, most of which were created when the land was open space.

"They were places that people thought were good places to bury stuff or dump stuff," said Michael Kanner, who heads the state Superfund program for the Minnesota Pollution Control Agency. "Some of the industries needed more land. ... It was easier to move outside the city."

The Star Tribune found that of the 20 significant pollution plumes, 17 are in suburbs. The list is based on the newspaper's interviews with regulators and public health officials and a review of state cleanup and monitoring records and data. Ten areas on the list are greater than 1 square mile.

State Pollution Control Commissioner Brad Moore said cleaning up groundwater is a long-term commitment, "and we have to be vigilant to ensure the resources are there in 10, 20, 30 years from now."

One of the largest problems is the 7-mile-long blob containing solvents from the former Twin Cities Army Ammunition Plant in Arden Hills that has spread to northeast Minneapolis and the Mississippi River. At its widest point, the plume is 11/2 miles across.

The U.S. Army and civilian contractors dumped chemical wastes at the plant from the 1940s on. The chemicals seeped into a drinking-water aquifer, and reached municipal wells in New Brighton, where it was discovered in 1981.

For 17 years, huge carbon filters have purified the contaminated water for New Brighton's water system, removing thousands of gallons of solvents, according to the Army. Much more has been extracted from groundwater and treated onsite.

"What is being drawn out of the wells now probably was dumped in the 1950s and later," said Mike Fix, director of the Army installation. The plant last produced ammunition in 1975.

The filtered water is considered safe to drink, and all the pumping helps shrink the underground plume. Levels of TCE have dropped, even though last year the levels in one well were 600 times the federal standard.

So far, the Army has spent $186 million cleaning up pollution from the plant, more than half of that to deal with chemicals in groundwater, Fix said. The work will likely continue for 20 to 40 more years.