BEMIDJI, Minn. (AP) – A federal program to clear the air in natural areas may mean rate increases for electric customers in northwest Minnesota and eastern North Dakota.

Customers there already saw double-digit rate increases this year after the Minnkota Power Cooperative raised wholesale rates to pay for environmental upgrades to its coal-fired power plant in Center, N.D.

Minnesota Public Radio reported Tuesday that the Environmental Protection Agency now seeks another big upgrade.

The EPA will soon release a proposed plan to curb nitrogen oxide emissions in North Dakota. It’s part of a federal program to cut haze in natural areas like national parks.

The state of North Dakota is siding with Minnkota and is threatening to fight in court. They say the EPA’s technology would not produce noticeably better visibility than cheaper, state-favored technology.

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