The U.S. Environmental Protection Agency says state agencies need to take additional steps to protect drinking water in southeastern Minnesota from nitrate contamination.

The Minnesota Department of Agriculture, Minnesota Pollution Control Agency and Minnesota Department of Health responded to the EPA letter on nitrates in southeast Minnesota, saying it would release a plan of action in 30 days.

The EPA’s notice to Minnesota state agencies earlier this month came in response to a petition sent in April by environmental groups saying more action was required to protect water quality in the geologically porous “karst region,” which includes Dodge, Fillmore, Goodhue, Houston, Mower, Olmsted, Wabasha and Winona counties.

The group consists of the Minnesota Center for Environmental Advocacy, Environmental Working Group, Minnesota Well Owners Organization, Center for Food Safety, Clean Up the River Environment, Food & Water Watch, Friends of the Mississippi River, Izaak Walton League Minnesota Division, Land Stewardship Project, Minnesota Trout Unlimited and Mitchell Hamline Public Health Law Center.

In the joint statement, the three state agencies said they share the EPA’s commitment to protecting drinking water by addressing nitrate contamination and pledged to work together to develop a plan. The letter also stated that Minnesota already is working on long-term strategies to reduce nitrate contamination through better fertilizer and manure practices.

“While progress has been made, more work is required by state agencies, local governments, and industry partners to reduce nitrate levels in our lakes, streams and groundwater to protect drinking water for all Minnesotans,” the statement reads. “Our agencies will respond to the EPA within 30 days, as required.”

Minnesota Agriculture Commissioner Thom Petersen said the agencies look forward to working with the EPA on a solution that is best for the state.

“It’s not a new issue. It’s things that we understand, and we’ve been doing the work,” he said. “They’re asking us to do some more work, and we have been planning for a lot of that, so we’re going to work on addressing that.”