Two environmental groups have appealed the permits granted by the state Department of Air Quality allowing construction of new coal-fired power plant units. But officials of both plants say the plants will have modern pollution controls.

The plants are a 950-megawatt generating station to be built at the Intermountain Power Plant near Lynndyl, Millard County, and a new 270-megawatt unit proposed for Sigurd, Sevier County. The Sigurd plant is to be built by Nevco Energy Co., Bountiful.

Appeals challenging the plants' recent approval were filed by the Utah chapter of the Sierra Club and by the Grand Canyon Trust, requesting that the Utah Air Quality Board overturns the permits.

The IPP unit would be the third at the site. It "would result in a significant net emissions increase" in pollutants, including carbon monoxide, nitrogen oxides, sulfur dioxide, PM10 particulates, volatile organic compounds, lead and sulfuric acid mist, says the appeal.

Tim Wagner, conservation coordinator for the Sierra Club's Utah chapter listed the following totals for yearly releases from the plant: 496 tons of PM10, more than 2,500 tons of sulfur dioxide, almost 2,800 tons of nitrogen oxide, more than 5,900 tons of carbon monoxide, 107 tons of ozone and 83 pounds of mercury.

The appeal says the Sigurd plant would be built by the Sevier Power Company, whose parent company is Nevco Energy. It charges that this power generator "has the potential to emit 100 or more tons per year" of carbon monoxide, nitrogen oxides, sulfur dioxide and PM10.

The two are among four new coal-fired power plant units planned for Utah, said Tim Wagner, conservation coordinator for the Sierra Club chapter. Rounding out the four, he said, are a new 400-megawatt unit for the Hunter Power Plant near Castle Dale and an 80-megawatt facility in Eastern Utah, the Bonanza Plant. The last two are not as far along in the permitting process, he said.

Coal burning is inefficient and dirty, Wagner said in a telephone interview. Efficiency is an important issue because the less efficient a power plant is, the more air pollution it may release.

"Coal is simply the dirtiest fuel on the planet when it comes to producing electricity," he said. Burning coal is the largest source of airborne toxins in America and it puts out pollution that causes global warming.

Besides health concerns, the groups believe the Sigurd and IPP plants pose a serious threat to air quality at Utah's five national parks, Wagner said.

An official with Nevco, Bruce Taylor, responded that it's normal for coal-burning plants to release emissions. "You can't get electricity without doing something," Taylor said.