Several environmental groups have asked the U.S. District Court for the Northern District of West Virginia to allow them to join the EPA's side in a lawsuit that a West Virginia chicken grower has filed against the agency.

The farmer, Lois Alt of the Eight is Enough poultry farm in Hardy County, is suing the EPA, saying the agency overstepped its regulatory authority when it came to her farm in November 2011 and declared she was discharging pollution into waters of the state and needed a permit. Alt contended that the discharge was agricultural stormwater, which is exempted from regulation under the Clean Water Act.

Any discharge from the Alt poultry farm would flow into a ditch that reaches a creek that eventually flows into the Potomac River.

The court has already allowed the American Farm Bureau and the West Virginia Farm Bureau to intervene in the case on Alt's side.

The groups wanting to join include Potomac River-keeper, West Virginia Rivers Coalition, Waterkeeper Alliance, Center for Food Safety, and Food and Water Watch.

The case could become a watershed moment for the regulation of concentrated animal feeding operations and their disparate sources of potential discharge, some regulated and some not.

In the Alt case, the farm acknowledges a discharge, but said that it is from a non-regulated source — stormwater. The EPA contends the source is processed wastewater — which includes rainwater mixed with manure, dust particulates and dander — and is regulated.

"There are very tight limits on processed wastewater," said Scott Edwards, an attorney with Food and Water Watch. "The poultry CAFO industry understands that the way they operate, these farms pollute just as a matter of course. The Farm Bureau understands that they're going to have to get these kinds of exemptions into the Clean Water Act."

The Alt case began in June 2011, when EPA inspectors arrived on the farm, which grows 200,000 birds in eight chicken houses. The inspectors found man-made ditches on the property between the poultry houses, and manure on the ground that could be exposed to rain and flow into the ditches. The ditches flowed to an access lane, and the runoff from that lane is about 200 yards from Mudlick Run, a tributary of Anderson Run, which flows into the Potomac River's south branch.

The EPA found that the farm needed a discharge permit and was subject to fines if it didn't get one.

The EPA had hoped that it could make all CAFOs subject to permit requirements if they discharged pollutants now or could in the future. But in the case National Pork Producers Council et al. vs. EPA, the U.S. District Court for the Fifth Circuit said that the animal operation had to have an actual discharge, not just a potential one, to fall under the regulation. That ruling came down in 2011, which forced the agency to change the CAFO regulations it had been developing since 2008.

On the Alt farm, the inspectors said, the configurations of the ditches "would" result in a discharge when the rainfall interacted with manure, dander and other particulates. But the EPA's order doesn't say that the EPA documented any kind of discharge with water testing. Farm Bureau officials have argued in the agriculture press that the EPA is overreaching and ignoring the conclusions of the judge in the Pork Producers case.