Clark Fork River

Site History

In May 2004, the Record of Decision (ROD) for the Clark Fork River Operable Unit (CFROU) was released by the United States Environmental Protection Agency (EPA 2004). The 2008 Montana v. ARCO Consent Decree (CD) allocated $26.7 million (M), plus interest, to restore, replace, or acquire the equivalent of the injured aquatic and riparian resources of the Clark Fork River within the Clark Fork River Operable Unit (CFROU). The CFROU CD identifies two categories of restoration actions for the Clark Fork River: restoration actions and restoration in lieu of remedy. In 2019, the State updated the 2007 Restoration Plan by completing the Clark Fork River Aquatic and Riparian Restoration and Prioritization Analysis (Geum et al. 2019).  Restoration actions included in the proposed 2020 Restoration Plan Update were identified during implementation of the integrated remediation/restoration actions in completed phases of the Clark Fork River.

Natural resource injuries to the Clark Fork River by releases of hazardous substances are documented by the following (2007 Restoration Plan):

  • Surface water contains concentrations of hazardous substances that exceed criteria established for the protection of aquatic life and thresholds that have been demonstrated to cause injury to fish;
  • Bed sediments contain hazardous substances at concentrations that exceed baseline conditions by, on average, a factor of more than ten, and exceed concentrations that are expected to injure benthic macroinvertebrates;
  • Benthic macroinvertebrate tissues contain elevated levels of hazardous substances;
  • Consumption of contaminated benthic macroinvertebrates by trout has been shown to cause reduced growth;
  • Trout populations are approximately 20% of baseline levels due to exposure to and avoidance of contaminated surface water and consumption of contaminated benthic macroinvertebrates;
  • Rainbow trout are largely absent from the Clark Fork River upstream of its confluence with Rock Creek;
  • Populations of otter, mink and raccoons that rely on fish and benthic macroinvertebrates in their diet are significantly reduced relative to baseline conditions;
  • Approximately 200 acres of floodplain contain phytotoxic concentrations of hazardous substances to the extent they are entirely or largely devoid of vegetation having no or little capacity to support viable wildlife populations; and
  • Thousands of additional floodplain acres containing tailings and contaminated soils are limited, to various degrees, in the quantities and types of vegetation they can support and are a continuing source of hazardous substances to aquatic and riparian resources.

This property will be developed as a state fishing access site (FAS) to provide additional public access to Racetrack Pond and the Clark Fork River.  The proposed FAS developments include access roads, walking trails, boat launch, parking area including U.S. Americans with Disabilities Act (ADA) accessible parking, an ADA latrine and an ADA fishing access platform.  Habitat improvements include regarding of the pond area for the purpose of increasing the quality of shoreline vegetation, wetlands, waterfowl habitat, and aquatic habitat. A public meeting was held August 17, 2017 to discuss the Racetrack Pond FAS and habitat improvement project and the DRAFT EA, including the Proposed Action and alternatives. Slides from that presentation can be found here. Public comments on the Draft EA were due September 4, 2017.

NRDP