The company expects that the settlement, along with the current economic conditions, will lead to layoffs.

It said job loss numbers would not be determined until decisions were finalised.

The company has until June 1, 2015, to shutter the plants.

The settlement also includes a provision for WPS to install its ReACT environmental controls at its 321 megawatt Weston 3 generator.

The system will reduce emissions of several pollutants and position the unit to be in compliance with future EPA regulations.

The ReACT installation will be the first commercial application of this technology in the US.

Following Public Service Commission of Wisconsin approval, the ReACT project will take more than three and a half years to complete and bring more than 200 temporary construction jobs to the Wausau, WI area.

In addition, WPS agreed to tighter emissions limits than current air permits require for Pulliam units 7&8, as well as its other coal-fired generators system wide.

This could result in some of its coal-fired generators operating at lower capacity.

On top of this is the generation loss from Weston 1&2 and Pulliam 5&6.

Weston 1&2 have a combined nameplate capacity of 135MW and Pulliam 5&6 turn out 112.5MW.

WPS says any power lost will be replaced by a combination of natural gas-fired generation and purchases from the market.

The Pulliam units were built around 1950 while Weston 1 became operational in 1954 with Weston 2 following in 1960.

WPS previously installed emissions control technologies at both Weston and Pulliam to reduce sulfur dioxide, nitrogen oxide, mercury and particulate matter emissions.

The EPA had filed a notice of violation against WPS in 2009 alleging the utility had not obtained the proper air permits for improvements made to electricity generating units to ensure electric reliability as far back as 1994.

WPS did not admit any wrongdoing.