PPL Montana sued the U.S. Environmental Protection Agency on April 23 to prevent the agency from releasing data to two environmental groups about upgrades made to PPL’s 2,000 MW Colstrip coal-fired power plant.

According to The Associated Press, PPL claims in the lawsuit that the data the EPA plans to release includes 24 years' worth of capital improvement projects that the company considers confidential. The lawsuit also claimed that the company's competitors would be able to figure out the life of the individual units, and the likely timing for replacing components, which would allow them to compete through aggressive pricing and to “strategically time and improve their own capital improvement processes, all to PPL Montana’s detriment,” the article said.

The two environmental groups had requested the information through the federal Freedom of Information Act. The company said in the article that EPA notified them on April 9 that the data was not confidential and the agency would release the information to the groups after 10 business days, which prompted the lawsuit.

The plant was grandfathered in under the Clean Air Act and was not required to comply with tougher emissions control standards unless the plant's operator made upgrades modernizing it, according to the article.

The first two units of the power plant began operating in the mid-1970s, and two more units came online in 1984 and 1986.

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