As ethanol booms, groundwater needed for production could run low
By The Associated Press

MINNEAPOLIS — With Minnesota’s ethanol production expected to more than double by 2011, there’s growing concern there won’t be enough groundwater to satisfy the industry’s needs.

It already happened in Granite Falls, when a new ethanol plant last year depleted the groundwater so much that the plant had to start pumping water from the Minnesota River.
It takes four to five gallons of water to produce a gallon of ethanol at a biofuel plant. Minnesota has 17 ethanol plants in operation, six under construction and 10 more proposed or in the planning stages — substantially increasing the possibility of more drains on underground water supplies.

Right now, the industry is consuming about 2 billion gallons of groundwater a year, according to state estimates. The expected doubling of the state’s ethanol production would likely mean a quadrupling of the amount of water needed.

“I would characterize it as a concern about where we’re going to allocate groundwater over the next 10 years relative to what are the needs going to be in 20 or 30 years, and whether we’re doing a good job in thinking ahead,” Minnesota Pollution Control Agency Commissioner Brad Moore told the Star Tribune.

This week, at the request of the MPCA, the Minnesota Environmental Quality Board is convening an expert panel to look more closely at groundwater availability and ethanol production.

Among other information, that group will seek to find out just how much water is being stored underground in Minnesota. There’s currently a lot of uncertainty about that.

Even when ethanol plant developers test aquifers — the underlying layers of porous rock and sand that stores the water — the results can be misleading. In Granite Falls, developers obtained a three-year groundwater permit from the state, but had to switch to river water after just about a year.

Individual ethanol plants must obtain water appropriation permits from the Minnesota Department of Natural Resources, a process that requires owners of proposed plants to drill wells and conduct tests to determine how high-volume pumping will affect groundwater supplies. Once in operation, plants are required to monitor various wells constantly and report their findings.

Dale Setterholm, associate director of the Minnesota Geological Survey, said that the only way to know how much water can be tapped on a long-term basis is to document the location, size and number of aquifers in an area, how they are related to surface lakes and rivers and how they are recharged.

“A lot of that work has not ever been done,” he said.

The newly formed advisory group plans to take up that question in the coming weeks. John Wells, the strategic planning director for the state Environmental Quality Board, said the state will be well served by a more comprehensive look with how ethanol demands as well as population growth and other needs match up with available groundwater.

“It’s not a crisis, but it’s a lot different than saying we’ve got all the water we need and we’ll never need to worry about it,” Wells said. “We’re not there anymore.”

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