Iowa-based Grain Processing Corporation (GPC) is now exclusively using natural gas to power the boilers at its Muscatine wet milling facility.

The company said that its conversion from coal is part of its environmental sustainability efforts for reducing emissions in 2015. Two months ago GPC started operating its new dryer house, which is also expected to reduce its emissions in Muscatine.

“Cleaner air is a commitment GPC made to the Muscatine community. With dedication and hard work, we are able to achieve our promise. Replacing coal with natural gas as a fuel source will substantially reduce levels of sulfur dioxide, particulate matter, nitrous oxide and lead,” said Mick Durham, director of environmental services at GPC.

Durham explained that using natural gas is projected to reduce carbon monoxide emissions by 61 percent, nitrous oxide by 22 percent, particulate matter by 91 percent, sulfur dioxide by 99.9 percent and lead by 97 percent.

In December 2014 the U.S. Environmental Protection Agency approved Iowa’s state implementation plan to reduce fine particle emissions in Muscatine County. This required GPC and two other companies to reduce their emissions of PM2.5 — fine particles measuring up to 2.5 micrometers in diameter — such as those found in smoke and haze.

GPC was also required to “limit boilers to gaseous fuels only”, the Muscatine Journal reported.

“We have worked diligently and steadily to lower emissions through a number of projects and processes at GPC,” said company spokeswoman Janet Sichterman. “In May, GPC announced that its new $83 million dryer house became fully operational. These two efforts for controlling emissions have put GPC well ahead of industry peers.”