North Dakota's plan to end a four-year dispute with the federal Environmental Protection Agency over alleged air quality violations is in the hands of the federal agency.

The State Health Department recently sent off a draft agreement for the EPA's review, which should see action one way or another in January.

The dispute centers on whether the state violates allowable sulfur dioxide in Class I air areas, such as Theodore Roosevelt National Park.

Its resolution will play a major role in how or if any more coal-fired plants can be built here. New power plants are a big part of the state's economic development scheme, under a state-supported Lignite Vision 21 plan.

New coal plants at Gascoyne and South Heart are being studied.

The two sides set an August deadline for reaching agreement on the controversy. That deadline was extended twice and is no longer used by either side to describe any time limit.

North Dakota sent the draft agreement to EPA headquarters in Washington, D.C., reaching over the regional office in Denver where the allegations originated.

The dispute was kicked upstairs this fall, after state congressional leaders lobbied for the higher review in hopes of getting it resolved.

EPA officials in Washington did find for North Dakota in four of six broad areas of disagreement, thereby hugely reducing the amount of sulfur dioxide said to be in excess of the federal Prevention of Significant Deterioration or PSD program.

North Dakota's draft concept offers a plan to resolve the remaining two areas of disagreement.

David Glatt, state air quality chief, said the state wants two sulfur-emitting sources taken out of the PSD program altogether.

Under the program, new plants and more increments of sulfur dioxide pollution only can be added if the state shows they won't cause air quality to deteriorate.

In the '80s and '90s, federal land managers agreed that neither Dakota Gasification Co., nor the Little Knife Gas plant would deteriorate air quality.

Glatt said North Dakota officials think if the two sources were approved in the first place, they shouldn't be counted in the PSD program.

Those two plants account for 12,000 tons of sulfur annually, he said.

The regional EPA originally said North Dakota exceeds the sulfur limit by about 66,000 tons.

The Washington review and findings for North Dakota's position had already shaved 57,000 tons out of the violation zone.

In the second area of agreement, the state wants the EPA to measure air quality by using the sulfur pollution baseline established in 1977 from existing sources alongside actual measurements of sulfur in the Class I air areas.

The state contends actual measurements show North Dakota emits less sulfur all the time.

The federal program uses computer models to decide if pollution exists.

Glatt said he's eager for headquarters to review the draft and send it over to the regional office.

"The sooner there's certainty, the better," Glatt said.

Even if North Dakota is found to be in compliance with sulfur regulations, Glatt said it remains to be seen if there's "room under that bar to allow development."

Kerrigan Clough, regional air quality administrator, said he hasn't seen North Dakota's draft agreement.

Because of the pending holiday, no one at EPA in Washington was available for comment.

(Reach reporter Lauren Donovan at 888-303-5511 or lauren@westriv.com.)