Pigs are a big deal. Four in 10 pounds of meat eaten worldwide is pork and, in the United States alone, there are as many as 75 million or more pigs being grown for food. Since each pig can produce half to three-quarters of a ton of manure on its way to market, their wastes are a big deal, too.
Collected in open-air pits as they used to be on the 10 Murphy Brown hog farms in southwest Utah, the waste can be a smelly threat to...