Comments invited on environmental worksheet for landfill expansion near Mankato

Contact: Cathy Rofshus, 507-206-2608

Rochester, Minn.—Xcel Energy is proposing to expand its ash landfill near Mankato by 4.1 acres to prolong its life by about 13 years. The Minnesota Pollution Control Agency (MPCA) invites comments through Aug. 5 on an Environmental Assessment Worksheet for the expansion.

The landfill, currently about 47 acres in size, is located 3.5 miles southwest of Mankato next to the Blue Earth County Ponderosa landfill. It accepts ash from Xcel’s Wilmarth station in Mankato that burns solid waste to generate energy. The current MPCA permit allows the landfill to store a maximum of 1.6 million cubic yards of ash. The landfill has operated since 1987 and has about nine years of remaining site life based on current ash acceptance rates of 50,000 cubic yards per year from the Wilmarth station.

This expansion would increases its maximum capacity by 648,220 cubic yards – a 40 percent increase – and extend its life to 2035. The facility expects no increase in traffic – currently about 14 trucks per day – with the expansion.

To prevent contamination of groundwater and the nearby Blue Earth River, the expanded disposal area will be lined, using a system that goes beyond state requirements. The landfill also uses a system to collect and treat any rainwater or snow melt that contacts the buried ash. As with the current landfill area, the facility will use a system of wells to detect any contaminants in groundwater.

The MPCA is the agency responsible for issuing permits that set conditions on solid waste and stormwater to prevent pollution of resources. These permits will be open for public comment shortly. Blue Earth County is responsible for amending the conditional use permit and renewing the solid waste license.

The MPCA anticipates no adverse environmental impacts from the expansion.

State agencies use this environmental worksheet to decide whether a more complete Environmental Impact Statement is needed. The worksheet covers site location details, nearby resources and other elements, including wells, soil types, water use, air and odor emissions, and traffic.

To see the complete Environmental Assessment Worksheet, go to the MPCA website at, click on the “public notices” link in the right margin, and scroll down to July 6 for the “Wilmarth ash landfill” project.

Comments on the worksheet must be in writing and submitted by 4:30 p.m. Aug. 6 to Charles Peterson (651-757-2856), MPCA, 520 Lafayette Road North, St. Paul, MN 55155 or

For more information on the solid waste permit, contact Sherri Nachtigal of the MPCA at 507-206-2600 or