A new sewage plant in Arkansas that violates the Clean Water Act will further pollute Oklahoma’s scenic Illinois River, and sewage from the plant should not be discharged until a scientific study of the watershed is completed, a Tahlequah based conservation organization said in an appeal filed this week.

Over the objections of Save the Illinois River Inc. and the state of Oklahoma, the Arkansas Department of Environmental Quality gave permission last month to the Northwest Arkansas Conservation Authority to discharge into Osage Creek, a tributary of the Illinois River.

The plant serves Bentonville and smaller communities that do not currently discharge into the Illinois River watershed. NACA was limited to a phosphorous discharge of one part per million until 2012, when the EPA will require a limit 10 times more protective of water quality.

STIR’s opposition to the NACA Regional Wastewater Treatment Plant centers on phosphorus, a nutrient that degrades water quality and damages aquatic life. While Oklahoma has a limit for phosphorus in scenic rivers like the Illinois River, Arkansas does not, and has refused to list Osage Creek and the Illinois River as impaired waters. However, Arkansas classified both streams as impaired by phosphorus after the EPA objected.

Phosphorus enters water from sewage treatment plants and from “nonpoint sources,” including runoff from fields fertilized with poultry waste. Poultry farms are concentrated in northwest Arkansas and produce millions of tons of manure annually.

STIR President Kurt Robinson of Muskogee said STIR wants a public review and compliance with a TMDL – a study of appropriate limits – before NACA is permitted to discharge waste to the Illinois River watershed. The facility is now under construction.

“The NACA wastewater treatment plant will add approximately 30 pounds of phosphorous daily to streams recognized by the EPA and Oklahoma as already damaged by phosphorus,” said Robinson. “Neither Oklahoma nor Arkansas has conducted required studies to determine how much phosphorus can be added to the streams without causing further impairment. Oklahoma’s phosphorous limit for the Illinois River may be impossible to achieve because of the NACA facility. Tenkiller Lake, one of Oklahoma’s finest water resources, will suffer even further from algae growth if this permit is allowed to stand.”

Robert Kellogg of Oklahoma City, STIR legal counsel, said Arkansas authorities “recycled” a 5-year-old permit for a small facility that was never constructed.

“Bentonville was not included in the 2004 Osage Basin permit, and this plant is not part of a joint Oklahoma and Arkansas compact to limit phosphorus discharges from sewage plants in the Illinois River watershed,” Kellogg said. “Arkansas may say Bentonville was part of the agreement, but we feel the Federal Clean Water Act takes precedent.”

The NACA wastewater plant is designed to treat 3.6 million gallons of sewage daily and has a phosphorus limit of 1 part per million until 2012, when the EPA will require the facility to meet a limit of .1 parts per million. The cities of Fayetteville, Rogers, Springdale, Siloam Springs and Prairie Grove currently discharge treated sewage to the Arkansas portion of the Illinois River watershed. In Oklahoma, Westville and Tahlequah have existing discharge permits to the Illinois River with limits of 1 ppm of phosphorus.