momus says "much of it comes from the mining industry, power generation, and the military, all of which are exempt from following OSHA safety rules,". Funny, I worked in the power generation field for more than 30 years and never knew I could ignore all those OSHA rules and inspectors. And prior to that working in industry and being in part responsible in part for meeting EPA rules the one thing I learned was that individual households were by far the biggest polluters. Companies, ALL companies, are under constant inspection by Federal, State, County, City EPA inspection. A lot of common stuff you dump down the drain, multiplied by a 100 households, would any company heavily fined if they dumped the same amount down the drain.