Posted at: 10/29/2012 8:24 AM
Cliffs Natural Resources Inc. announced improvements to the storage landfill for coal ash generated at Northshore Mining’s power plant at the taconite facility in Silver Bay.
The improvements are in response to an incident that occurred in 2011, when leachate was mistakenly transported to the Western Lake Superior Sanitary District (WLSSD) wastewater treatment plant in Duluth.
Leachate occurs when moisture seeps through the landfill and mixes with the coal ash. This material is ultimately captured on the bottom liner of the landfill and routed to off-site containment for further management.
In this instance, leachate that had an elevated pH level was transferred to WLSSD, where it was processed without any damage to the facility or harm to the environment.
“We regret that this incident happened, but it has resulted in significant improvements to our landfill management practices,” said Ed LaTendresse, general manager, Northshore Mining. “We remain committed to Cliffs’ core value of environmental stewardship and are confident that these new methods will ensure the leachate generated by our power plant is handled appropriately moving forward.”
Improvements to Northshore Mining’s landfill management system include:
• Improved operating procedures and employee awareness training for leachate handling and management.
• Installation of continuous measurement instruments to conduct pH sampling of all leachate prior to transportation.
• Installation of a carbon dioxide aeration system to control leachate pH levels.
• Development of a plan of action if leachate exceeds mandated pH levels.
Northshore Mining has agreed to pay a $242,973 civil penalty to the Minnesota Pollution Control Agency (MPCA) and submit plans to the MPCA, which describe the actions being taken to ensure leachate is properly monitored and handled at the facility.
Northshore will also complete a Supplemental Environmental Project by making a $50,000 contribution towards expansion of the household hazardous waste product reuse center at the WLSSD facility in Duluth.
Supplemental Environmental Projects provide environmental benefits and are above and beyond what are normally required by environmental regulations.
In addition, Northshore has made a $25,000 donation to WLSSD to further their expansion plans for the product reuse center. “WLSSD provides a great service to the area by collecting items that can be reused by the community,” said LaTendresse. “We hope our donation will help the facility meet the increased demand for this valuable service.”