P.O. BOX 70
Polson, MT 59860
February 10, 2025
Department of Environmental Quality
Montana Ground Water Pollution Control System
P.O. Box 200901
Helena, MT 59620-0901
Subject: Comments on Tentative Determination to Issue MGWPCS Permit #MTX000307 to Lakeside County Water and Sewer District
To Whom It May Concern,
The Flathead Lakers is a nonprofit organization dedicated to protecting clean water, healthy ecosystems, and quality of life in the Flathead Watershed of Northwest Montana. With over 1,000 members, many of whom own property on Flathead Lake and within its watershed, we have long supported efforts to protect water quality through research, advocacy, and collaboration.
Flathead Lake is a local, state, and national treasure. Surveys indicate that the public prioritizes water quality protection in the Flathead region. The potential long-term impact of wastewater discharge on groundwater and surface waters must be carefully assessed to ensure that this permit does not compromise the high water quality standards essential for environmental health and long-term healthy economic growth.
We recognize the need for expanded wastewater treatment capacity in the Flathead Valley and acknowledge that the proposed Rapid Infiltration Basins (RIBs) represent an improvement over the current practice of spraying partially treated effluent on fields nearing capacity. This proposal represents an important step forward in addressing the region’s wastewater challenges by transitioning to a method that could reduce nutrient loading on the valley floor. However, despite these improvements, we remain deeply concerned about the suitability of the selected site, treatment efficacy, and potential impacts on groundwater and surface waters, including Wiley Slough, Ashley Creek, the Flathead River, and Flathead Lake.
Concerns about soil and groundwater suitability: The Environmental Assessment (EA) identifies that the groundwater table at the proposed RIBs site is only 10–20 feet below the surface, and it acknowledges that nutrients will enter the groundwater and flows north toward Wiley Slough and Ashley Creek, both of which are hydrologically connected to Flathead Lake.
We recommend that alternative sites with deeper groundwater and better soil filtration be evaluated and publicly disclosed.
Soils in the area are classified as Da soils (loamy sand), which, according to the USDA Web Soil Survey, have very limited filtration capacity for wastewater treatment. This raises substantial concerns regarding the site’s ability to adequately filter effluent before it enters the groundwater.
We recommend that further a site-specific hydrogeologic study and permeability analysis be conducted to confirm that the soil and groundwater conditions can effectively treat nutrients before reaching surface waters. Additionally, a nutrient attenuation study should be required to evaluate how effectively the soil can prevent nutrient migration to surface waters. The permit should include strict nutrient monitoring requirements with clearly defined thresholds for corrective action.
Contamination in wastewater by per- and polyfluoroalkyl substances (PFAS) is an emerging concern nationwide. The EA does not address whether PFAS will be present in the effluent, nor does it outline any monitoring protocols for PFAS in groundwater or composted solids from the facility.
The permit should require PFAS testing in both groundwater monitoring wells and the composted biosolids used for land application. If PFAS levels exceed safe thresholds, the permit should outline corrective measures to prevent contamination of drinking water sources.
We acknowledge that land options are limited, but the EA does not provide a comparative analysis of alternative sites with deeper groundwater and more effective filtration capacity. The Department of Environmental Quality (DEQ) should require a comprehensive site alternatives analysis before approving this permit. If the proposed site is chosen despite these concerns, mitigation measures must be clearly outlined to prevent groundwater contamination.
If this project proceeds, it is imperative that groundwater monitoring results be made publicly available in a clear and accessible format. Furthermore, the permit should include explicit enforcement measures if nutrient levels exceed projected limits.
We recommends that DEQ:
require quarterly public reporting of groundwater quality data, including nitrogen, phosphorus, and PFAS levels,
establish a contingency plan that outlines corrective actions if water quality standards are exceeded,
define clear enforcement mechanisms, including potential suspension of operations if nutrient contamination is detected at levels exceeding regulatory thresholds.
We appreciate the progress represented by this proposal and acknowledge its potential to reduce environmental impacts compared to current practices. However, without proper safeguards, this project still poses a significant risk to groundwater and surface water quality, impacting Flathead Lake’s ecosystem and economy for generations. We respectfully request that DEQ reassess the site’s suitability and include stronger monitoring, mitigation, and enforcement measures before finalizing the permit.
Thank you for your consideration. We appreciate your commitment to protecting Montana’s water resources.
Sincerely,
Coby Gierke
Executive Director
Flathead Lakers