The joint motion, filed by AFBF, West Virginia Farm Bureau and West Virginia poultry farmer Lois Alt, would garner a big win for farmers nationwide if the court rules in their favor.

The motion comes on the heels of the court’s April decision rejecting efforts by the Environmental Protection Agency to dismiss Ms Alt’s case in its entirety in order to avoid defending its legal position in court. This lawsuit began in 2012 when Alt challenged an EPA order demanding that she obtain a Clean Water Act discharge permit for ordinary stormwater runoff from her farmyard or face $37,500 in fines each time the stormwater came into contact with dust, feathers or small amounts of manure on the ground outside her poultry houses as a result of normal farming operations. Despite EPA’s withdrawal of the Alt order six weeks before the legal briefing was scheduled to commence, the court agreed with Farm Bureau and Alt that the case should go forward to clarify whether, as EPA contends, discharge permits are required for "ordinary precipitation runoff from a typical farmyard."

"For the last year Lois Alt has courageously held her ground against EPA not only to defend her own farm, but to help stop EPA from using its muscle against other responsible farmers," said AFBF President Bob Stallman. "We are honored to join with her to explain to the court how EPA is misinterpreting the Clean Water Act and unlawfully using the full force of the federal government to force farmers to seek permits when they are not discharging to waters."

According to the legal papers filed, Farm Bureau and Alt ask the court to rule that stormwater from Alt’s farmyard, which contains dust and other particles emitted or spilled as part of normal farm operations, is within the meaning of the Clean Water Act’s exemption for "agricultural stormwater." It asks the court to rule that EPA exceeded its authority in finding stormwater from Alt’s farmyard was a Clean Water Act discharge and in ordering Alt to obtain permit coverage.

"For the past decade, we have successfully challenged EPA’s efforts to require discharge permits for concentrated animal feeding operations that don’t discharge," said Mr Stallman. "Lois Alt’s courage in taking a stand against EPA will help ensure that EPA cannot get around those important court rulings by mischaracterizing rainwater from a well-run farm as an illegal discharge."

EPA is expected to file its own motion with the court defending its position, and opposing Farm Bureau and Alt’s motion on 1 August. Several environmental groups have intervened on behalf of EPA and will file a brief as well.