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State Halts Construction on Wastewater Treatment Plant Amid Environmental Violations by Contractor

  • July 21 2023

HELENA— In collaboration with the Architecture & Engineering Division of the Montana Department of Administration (A&E), the Montana Department of Environmental Quality (DEQ) this week called for a pause in construction on a wastewater treatment system upgrade project amid recent environmental violations by an independent contractor.

Missouri River Contractors (MRC) was upgrading a wastewater treatment plant at the Montana State Hospital in Warm Springs, until A&E issued a Stop Work Order following permit violations and insufficient corrective actions by the contractor. The contractor’s actions resulted in the unintentional release of more than 3 million gallons of partially treated wastewater into Warm Springs Creek. The discharge of partially treated wastewater has been stopped.

Given the information and water testing from the point of release, short-term human health effects are not expected and there is currently no known risk to water quality. Work on the project will not resume until DEQ is confident that environmental protections are in place.


  • On June 23, 2023, DEQ was notified of potential Water Quality Act violations by the onsite project engineer. DEQ inspectors visited the site numerous times in the subsequent weeks, working with the contractor to collect water samples and assess any impacts to water quality.
  • DEQ issued a Violation Letter on July 12 and again on July 18, then called for a pause in construction after MRC repeatedly failed to operate in compliance with approved permits and plans, or implement environmentally protective measures known as best management practices.
  • After MRC’s corrective actions proved insufficient, A&E issued a Stop Work Order on July 18, 2023, pending corrective action to address violations.
  • Violations by MRC include impacts to water quality, conducting construction activities and disturbance in areas not covered by the permit, and failing to comply with permit requirements related to its Montana Pollutant Discharge Elimination System (MPDES) permit. MPDES permits are key to protecting state waters under the Montana Water Quality Act and ensure protections are in place to prevent potential pollution that could harm human health and the environment. Failure to comply puts Montana’s waterways at risk.
  • While the Montana State Hospital has a valid permit to discharge treated wastewater, MRC’s work on the project resulted in unintended leaks from the wastewater treatment ponds prior to full treatment.
  • Water quality sampling at the discharge point documented two exceedances of permit limits. The measured pH on June 27 was 9.23 compared to the permit limit of 9. Additionally, total suspended solids—typically sand, silt, and organic matter such as bacteria or algae—measured at 11% removal compared to the permit requirement to meet 85% removal. Sampling showed no other violations of permit limits.
  • DEQ and all state agencies take permit violations seriously and will hold contractors accountable. They encourage contractors to ensure their operations comply with approved site plans and permits.

DEQ and A&E continue to monitor the situation and work with MRC to address the violations, ensuring the project moves forward in a responsible, protective manner which does not put Montana communities or the environment at risk.

Tags: Press Release

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