MADISON, Wis. (AP) — Wisconsin Gov. Tony Evers is pushing to toughen state rules to reduce nitrate contamination in ground and surface water as concerns grow about pollution across the state.

Evers announced Wednesday that he is directing the state Department of Natural Resources to establish nitrate performance standards for soil most likely to be contaminated.

Environmental group Clean Wisconsin praised the news, saying creating new rules for how nitrates are applied to farm fields is an important step for protecting rural drinking water across the state.

Evers is directing state agencies to start the process of creating a rule that will govern the level of nitrates that will be allowable. Studies have shown that agricultural sources such as manure and commercial fertilizer are the most common sources of nitrate pollution.