Alva Review-Courier -

A group of poultry producers, including the world's largest, have asked a federal judge to dismiss his ruling that they polluted an Oklahoma watershed.

Arkansas-based Tyson Foods, Minnesota-based Cargill Inc. and the others say in a motion filed Thursday that evidence in the case is now more than 13 years old.

"This case is constitutionally moot because the Court can no longer grant any effectual relief," the companies argued in a filing with U.S. District Judge Gregory Frizzell in Tulsa.

The filing said Oklahoma conservation officials have noted a steady decline in pollution. It credited impr...