Discharge to increase to 1.87 million gallons on a daily basis

Wednesday, May 8, 2002

For previous coverage of the cleanup, go to http://mlive.com/aanews/special/pall/

The state will allow Pall Life Sciences to increase significantly the amount of treated wastewater it dumps into the Huron River watershed despite concerns about polluting Ann Arbor's main source of drinking water.

City officials say they plan to question the Department of Environmental Quality over its decision to let Pall dump 60 percent more wastewater each day.

In granting Pall's request for the increase, the state acknowledged several environmental concerns voiced at public hearings, but said the risk is minimal.

Pall's permit for putting wastewater into Honey Creek, a tributary of the Huron, was expanded to 1.87 million gallons daily, from the previous 1.15 million.

It's part of a long-term groundwater cleanup of 1,4 dioxane, an industrial solvent used by Pall's predecessor, Gelman Sciences, to make medical filters. Wastewater from the cleanup has been discharged off and on since 1993 and into Honey Creek since 1997.

The city collects about 80 percent of its drinking water from the river, downriver from where Honey Creek empties into the Huron. The amount of dioxane in the treated wastewater is well below safe water minimums and is diluted even further when added to the river. In addition, the city adds in well water and also tests and treats the water used by Ann Arbor's 120,000 residents.

But a worst-case scenario acknowledged by the state in its latest report is that the increased discharge by Pall might cause pollution to rise during times when the river is very low. If the river is low while the company is discharging water at this new capacity, the report says, up to 2 parts per billion of dioxane could be detected at the city's water intake.

While that amount is well below the state's dioxane limit of 85 ppb, it's still too high for city officials. When they recorded 2 ppb in the city's Montgomery Well in March 2001, they took it off line as a precaution.

"We would be concerned with any level," said city Water Utilities Director Sue McCormick. She said city officials would talk this week with state Environmental Quality officials about the permit.

"In the case of Montgomery Well, we had the flexibility because we have other sources" of water, said Water Treatment Plant Superintendent Sumedh Bahl. "Here (in the Huron) it would have a major impact."

In addition to the Montgomery Well and the Huron, Ann Arbor water comes from the Steere Farm Wells, near the Ann Arbor Airport.

Pall officials say they are confident everyone's water is safe. The company requested the increase to help meet a court-ordered deadline to finish the dioxane cleanup by July 2005. Without the increase, they wouldn't meet the deadline and the company could face millions of dollars in fines, officials said.

Farsad Fotouhi, vice president for corporate environmental engineering and Pall's expert in charge of the cleanup, said the concentration of dioxane discharged is about half of level the state allows, making it cleaner than it legally has to be.

Pall has cleaned more than 1.1 billion gallons of groundwater and removed some 41,000 pounds of dioxane.

Dioxane was used to make filters at the Wagner Road plant until the mid-1980s. The company disposed of its wastewater by spraying it over grounds and storing it in on-site lagoons, which was legal at the time.

But the solvent, which binds to water readily, seeped into the ground and eventually showed up in residential wells a mile away from the company's Wagner Road facility. Some levels were thousands of times what the state deemed safe for drinking.

Residents who live along the creek have long been worried about dioxane seeping into their wells.

"It's not a good situation," said Roger Rayle, vice chairman of Scio Residents for Safe Water, a grassroots group that started in response to the dioxane controversy. "We're 70 percent water. We should act accordingly."

Tracy Davis can be reached at tdavis@annarbornews.com or (734) 994-6856.