HELPER -- One of Utah's smallest power plants will close next year because of new federal limits on mercury emissions.
The Salt Lake Tribune reports the Carbon Power Plant near Helper is being slated for early retirement after 60 years.
Rocky Mountain Power says the plant's location inside a tight canyon doesn't leave enough room for emissions controls that are being required of coal-fired power plants.
The utility would need to add a "bag house" to filter toxin-bearing particulates from the exhaust stacks.
Utah and Rocky Mountain Power will still rely heavily on coal-fired power - it accounts for 60 percent of the utility's generating output. Utilities are increasingly turning to cleaner-burning natural gas to make electricity.