Landowners along Highway 10 west of the Missoula airport are concerned that their drinking water may be contaminated by raw sewage dumped on private land on a nearby hillside. One landowner, who asked not to be identified, has been bleaching his well for several months and hauling drinking water from another source. He suspects that his well was infected by the sewage, which has been dumped on the hillside near Butler Creek for years.
Though pumping raw sewage from private septic tanks and dumping it directly onto the ground sounds disgusting and potentially harmful to human health, it is, in fact, legal and highly regulated.
Paul Hanson owns the 1,600 acres of land in question. Two septic companies pay him a small fee to dump about 20 loads a month on some 200 acres.
“It’s been going on for 10 years,” Hanson says. “This [complaint] is the first I’ve heard of it.”
Private septic pumping businesses have three options when it comes to getting rid of sewage. They can dump it into municipal sewage treatment plants, onto land owned by the person having his septic tank cleaned or onto another piece of land by agreement with the landowner.
“What the septic pumpers will do is find some farmer whose land is lying fallow” and contract privately for disposal rights, says Ed Thamke, who handles such complaints for the Montana Department of Environmental Quality (DEQ).
The DEQ licenses all septic pumping businesses and regulates the disposal process. County sanitarians must approve the disposal site.
Sewage cannot be dumped where food crops are being raised, and dairy cows cannot be grazed on the land. Sewage cannot be dumped on steep slopes or within 100 feet of drinking water. Hanson’s land meets all the criteria set by the state; he owns beef cattle but no dairy cows, and he moves the herd around to keep it away from the disposal sites.
Even if domestic wells are contaminated by bacteria, there’s probably no way to trace the contamination to its source, he says. If domestic wells along Highway 10 are contaminated by bacteria from raw sewage dumped uphill, if would be difficult to prove its source, says Thamke. Water moving underground can be diverted by natural barriers, and may not flow in an obvious, river-bound direction. In this case, there was once a rendering plant and feed lot on property near the wells in question. If the wells are contaminated, as landowners fear, the contamination might be from those old sources.
Nevertheless, the DEQ investigates every complaint, and accepts anonymous complaints as well.