Minnesota's largest potato producer is backing away from a controversial expansion just south of the Mississippi River headwaters after state regulators insisted on an environmental study of the potential contamination of groundwater.

For local citizens, who for years have been urging the Department of Natural Resources (DNR) to consider the wider impact of expanding row crops and irrigation in a region prized for its forests and clean lakes, it's a small victory. For R.D. Offutt, a major supplier for McDonald's French fries, the decision seems to be targeted regulation that will force it to take its business out of state, according to an angry letter the company sent the DNR.

Now, however, the state may not conduct the environmental study, even though irrigation and conversion of forest to row crops continues to expand over a large and sensitive aquifer — one that provides drinking water for the entire region of the state and is a primary source of water for the Mississippi.

"We continue to be concerned about potential for nitrate contamination," said Barbara Naramore, DNR assistant commissioner. But since R.D. Offutt has withdrawn the three high-capacity well permit requests that triggered the DNR's proposed assessment, it's not clear whether it can proceed, she said.

The expansion of agriculture into the pine forests west of Brainerd and south of Itasca State Park has been a contentious issue for years, triggered by the sale of tens of thousands of acres of Potlatch Corp. timber lands. The sandy soil is perfect for growing potatoes and corn — as long as the crops have irrigation. But those coarse soils also carry fertilizer and other farm chemicals straight into the shallow Pineland Sands Aquifer, where they are contaminating drinking water in private wells and community systems.

In 2015 the DNR initiated an environmental review when R.D. Offutt asked for 54 high capacity well permits for new agricultural fields. Its large expansion into thousands of acres of previously forested land was designed in part to reduce nitrate contamination. The company was seeking more land so it could add less fertilizer-hungry crops into its seasonal rotation without cutting back on potato production. DNR relented on the review when the company withdrew all but five permit applications. It also turned down a petition signed by 700 local citizens who still wanted an environmental review.

Instead, the company and the DNR agreed to cooperate on a much broader study of irrigation in the 750-square-mile aquifer. It would have considered sustainable use, health impacts from exposure to farm chemicals and alternative agricultural practices to reduce impacts.

But the Legislature declined to fund the study.

Irrigation doubles

The problem has continued to grow. Since 2015, the DNR has issued a total of 25 new high-capacity well permits — including five to R.D. Offutt — and renewed existing ones. And since 2005, the amount of groundwater withdrawn from the Pineland Sands region has doubled, reaching 10.7 billion gallons annually in 2017.

And local residents were still worried. For Mike Tauber, who lives in Backus with his wife and two sons, the breaking point came when he came home and couldn't see his house because of what he thought was smoke from a forest fire. After he realized it was dirt blowing in the air, he and his wife drove around to find the source — a newly plowed field that used to be a pine forest.

"I always thought our problem would be forest fires," he said "But it was a dirt storm."

After that, Tauber began working on another petition, with the help of the grass-roots advocacy group that filed the first one, asking the state to conduct an environmental review. He stayed up late nights writing it, learning the regulatory process and the history of previous efforts. Then he and his wife went door to door asking people sign it. Of the 120 or so people they asked, only three declined.

"There are so many people mad about this issue," he said. "You can't feed the world while you're poisoning your neighbor," he said.

He ended the 129-page petition by asking, "Do you want to be able to drink water without treating it, go outside without thinking about chemical exposure? Do you want to hunt, fish, and gather, swim in lake, pond or stream?"

He sent it in May.

Too much

Last week the DNR informed R.D. Offutt that it would look at the cumulative impact of its pending permit requests on nitrate contamination of the aquifer. That was a far smaller environmental review than Tauber asked for, but it was too much for the company.

In a letter last Monday, the company wrote, "The burdens of doing business in Minnesota outweigh its benefits, particularly when the Company sees others obtain numerous appropriation permits to farm new land in the Pineland Sands Area, without being required to undergo environmental review."

The company has some 200 irrigation permits in the Pineland Sands region, and has relationships with farmers who have many more. But, it said in the letter, in the last three years it added only five new permits to previously unfarmed land.

Given the difficult regulatory environment, the letter said, the company's Potlatch land is for sale, and it continues to look for opportunities in other states.

Mark Dickerson, a spokesman for R.D. Offutt, declined to comment further.

"We just decided pursuing the permits is not in our best interest," he said.

Tauber said he knows the problem is much bigger than R.D. Offutt, and he's hopeful that the growing public frustration will start to turn the tide on what he calls the "chemical conveyor belt."

Naramore said DNR officials would still like to do the broader study.

But that will require funding from the Legislature, she said.

Josephine Marcotty • 612-673-7394