Prairie River Minerals demonstration project

Prairie River Minerals, LLC (PRM) proposes to collect and process legacy stockpiles for a demonstration project near Coleraine, Minn. The project will produce high-grade iron lump and sinter using an ultra-high dense medium separation (UHDMS) technology. The finished products will be shipped off-site to evaluate potential use in steel manufacturing. PRM proposes to process up to 6.5 million metric tons from the Buckeye Mine (500,000 metric tons) and Seven Cities Stockpile 39 (6 million metric tons) natural ore legacy stockpiles. PRM's existing Demonstration Project processing plant will be used to process the Seven Cities Stockpile 39 Extension material. No changes to the existing processing plant layout or benefaction process are proposed. The proposed project is expected to last for a period of approximately 4 to 5 years.

Permits needed

The Prairie River Minerals demonstration plant is located near Coleraine, Minnesota.

Water permit

A water permit is a legal document that describes how a facility must operate in order to meet federal and state water quality requirements. The manner in which wastewater generated by the facility is managed and disposed of determines what type of permit is needed and what specific regulations apply. When reviewing the application materials, the MPCA reviews how the facility generates and disposes of wastewater and develops permit conditions and monitoring and reporting requirements. The MPCA drafts a water permit detailing these requirements and a statement of basis which contains the justification for the permit requirements.

The MPCA issued a State Disposal System (SDS) water permit for the Prairie River Minerals demonstration project on October 28, 2020. The SDS permit included:

  • Requirements that ensure a surface discharge does not occur and provides protections to groundwater quality.
  • Provisions that requires Prairie River Minerals to submit an application for a major modification of the permit (with opportunity for public comment) should they wish to extend the demonstration project, go full-scale or to otherwise exceed the processing of 500,000 metric tons of material.

The MPCA intends to issue a modified State Disposal System (SDS) water permit for the Prairie River Minerals demonstration project in 2021 to be preceded by a public comment period. The modified SDS permit includes an expansion of original scope to include:

  • A total of 6 million metric tons from the Seven Cities Stockpile 39 (in addition to the 500,000 metric tons in the October 2020 permit).
  • Elimination of WS-001 (due to expansion)
  • Addition of WS-003 (western infiltration basin) and WS-004 (east infiltration basin)

Water permit documents

Air permit

An air permit is a legal document that describes how a facility must operate in order to meet federal and state air quality requirements. The type and quantity of pollutants emitted determines what type of permit is needed and what regulations apply. When reviewing the application materials, the MPCA determines how each piece of equipment must operate, often setting maximum production rates, emission limits, monitoring, and recordkeeping requirements. The MPCA drafts an air permit detailing these requirements and a technical support document (TSD) which contains the justification for the permit requirements.

The MPCA issued an air permit on November 10, 2020.

The permit covers operations at the Prairie River Minerals facility that emit air pollution, which includes primarily dust from the excavation of stockpiles and from material crushing and handling and vehicle traffic on haul roads. There will be several space heaters on site. The permit includes a Fugitive Emissions Control Plan which identifies primary and secondary controls to mitigate potential dust issues at the facility. The permit also requires the company to:

  • track monthly and annual material processes;
  • performance testing requirements for material processing equipment; and
  • recordkeeping for visible emissions related to fugitive dust.

Air permit documents

For more information

Water quality: Kurt Carlson, 651-757-2881

Air quality: Ben Wenkel, 651-757-2603