Doug Cutler lives about 1,000 feet away from a hog feedlot near Rapidan. He says he’s gotten used to the stink (even though he no longer eats pork), but visitors ask him how he tolerates it. Blue Earth County is examining a technology called biofilters that cut down on the smell.

“It smells like decaying flesh,” said Cutler, who lives about 1,000 feet away from a hog barn near Rapidan. “Like something has died.”

Blue Earth County is beginning a discussion on an effective way to cut down on that smell. They’re called “biofilters,” and a 2004 University of Minnesota study reported they reduce odor by as much as 95 percent.

Biofilters are simple.

Air from the hog barn is forced out a vent and through an organic filter, usually consisting of compost or wood chips. Microbes living in the filter convert the smelly organic material in the air into carbon dioxide and water.

Dodge County, in southeast Minnesota, requires biofilters for every hog barn of 500 animal units or greater. That’s about 1,200 full-grown pigs.

Ken Folie, Dodge County feedlot officer, said the biofilters have been successful.

He said the cost depends on how much of the work the farmer puts in. A farmer who does most of the labor can expect to spend between $2,000 and $4,000, but that can increase by 50 percent if a contractor installs the biofilter.

Source: Mankato Free Press