On January 23rd, the Montana Department of Environmental Quality (DEQ) will hold a public hearing in Hamilton to gather testimony regarding renewal of the wastewater discharge permit for the Grantsdale Addition subdivision. This is our chance to identify substantive concerns and to share our support for clean and healthy drinking water, streams and rivers. The original permit was issued in 2006 but the five year time limit expired without any activity and the permit now must be renewed. This permit must be approved by DEQ before the subdivision can receive final plat approval by Ravalli County commissioners.
The high density rural development just south of Hamilton is proposing an on-site wastewater disposal system that will deliver an average of 40,000 gallons per day of septic wastewater to the ground and the aquifer supporting neighboring wells and the nearby Skalkaho Creek and Bitterroot River. If approved by the DEQ, wastewater containing nitrates at more than twice the concentration known to cause health effects in infants and pregnant women, and 80 times the level known to cause impairments to waterways, will be released into the aquifer.
This type of subdivision wastewater treatment is not unique to the Bitterroot Valley. The proliferation of the use of septic tanks and drainfields for wastewater disposal in rural sprawl developments is incrementally poisoning several of Montana’s aquifers and the drinking water they supply with a toxic mix of nitrates, herbicides, pesticides, solvents, detergents and pharmaceuticals.
Montana is an arid state and generally our rivers rely upon groundwater for base flow during the dry months. So, this pollution also ends up in our rivers and streams, choking them with oxygen eating algae and slime and impacting their aquatic habitat and recreational value.
On-site wastewater disposal systems have been a boon to rural land development for more than a century and are promoted as inexpensive to install and an effective treatment of domestic waste. Solids settle in the septic tank and the liquid wastes end up “out of sight, out of mind” in the ground. The ground is then intended to provide treatment and filtration of the wastewater, making it safe to mix with groundwater and be usable, again, for drinking. Unfortunately, the long term outcome is all too often contradictory because of the sheer number of these systems and the volume of pollution injected into the ground.
Waters in formerly pristine aquifers in developing rural areas across our state are becoming a toxic stew – unhealthy to drink and fouling our rivers. In addition, when septic systems fail, and they ultimately do, their final legacy is all too often the taxpayer expense to connect the failed system to a public sewer and pipe in a clean water supply.
Exacerbating this problem in Montana, many commercial developments and high density rural subdivisions are choosing large-scale on-site disposal systems because of the relatively low cost to install and operate. This is done legally through a regulatory loophole called “mixing”. If the case can be made that there is enough groundwater to dilute the toxins to a safe level before it gets to a neighbor’s water well, the pollution is allowed. Unfortunately, this loophole does not include consideration of cumulative effects of other on-site disposal systems or the potential effects of this pollution when it flows, as it will, to the nearest streams and rivers or neighbor’s drinking water well.
In recent years, the Bitterroot and many other streams and rivers in Montana have been determined by DEQ to be “impaired” from the nitrate pollution originating to a large degree from septic systems. We have clearly reached the tipping point where allowing more will only add to the environmental damage and risk to public health.
DEQ is taking public comment for the Grantsdale Addition. A public hearing to receive comments and testimony is scheduled for January 23rd at 5:30 pm in the Ravalli County Commissioner’s Conference Room. Written comments may also be provided to DEQ at http://www.deq.mt.gov/notices/WQnotices.mcpx.
Kelsey Milner, Hamilton
John Rundquist, Helena