work underway on a water-discharge structure we designed for poor soil conditions
project filter
downloadable resources
back to projects

environmental permitting for iron-nugget plant

environmental permitting for iron-nugget plant
Mesabi Nugget
Hoyt Lakes, Minnesota

permitting strategies enable rapid startup of pioneering taconite plant

In 2004, Mesabi Nugget LLC proposed constructing a prototype iron-nugget production facility at a former mining site in northern Minnesota. The plant would be the first in North America to employ a revolutionary technology that converts taconite ore, which is approximately 65-percent iron, into nuggets that are 97-percent iron—improving the efficiency of steelmaking while reducing costs and environmental impacts.

Working to meet a tight legislative deadline that exempted environmental review, Barr completed applications for a major PSD air quality permit, an NPDES and SDS permit, and a stormwater-construction and operation permit. Our air-permitting work included:

  • conducting an air emissions inventory, Class I and Class II dispersion modeling, and an air-emission risk assessment (AERA)
  • performing a BACT analysis for the rotary-hearth furnace and associated equipment
  • negotiating permit limits and studies to improve reductions of SO2, NOx, and mercury emissions 
  • completing a case-by-case MACT analysis based on the BACT analysis and a comparison with MACT standards for other industries
  • conducting a comprehensive risk assessment for human-health and ecological impacts

Despite the water supply, which did not meet quality standards for four pollutants, we successfully negotiated an NPDES permit with variances, as well as a reasonable schedule for demonstrating the effectiveness of a new mercury filter and protection of the receiving and downstream waters.

In the second phase of the project, we prepared a joint state and federal Environmental Impact Statement, designed a tailings basin, and developed a reclamation and closure plan that included stockpile reclamation; watershed, wetland and creek restoration; deep-water habitat creation; vegetation establishment; and monitoring and maintenance of the areas to be reclaimed.

The Mesabi Nugget facility has been successfully producing taconite pellets since January 2010 and is on track to meet its projected annual production capacity of 500,000 metric tons by the end of 2011.