COAL ASH DISPOSAL AND REUSE IN WISCONSIN

Wisconsin generates 1.4 million tons of coal ash annually and has the highest number of documented coal ash contamination sites in the U.S. While the state maintains a high recycling rate of at least 85% due to stringent disposal costs, many existing ponds are over 30 years old and lack liners or leachate collection systems. The document identifies 13 specific contaminated sites and highlights a 2011 bluff collapse at the Oak Creek Plant that released coal ash into Lake Michigan.

• Wisconsin generates 1.4 million tons of coal ash per year, ranking 28th in the United States. The state's coal ash ponds are aging, with none being less than 24 years old and 15 exceeding 30 years of age. A 2010 EPA risk assessment found that four ponds and landfills in the state are unlined and three are only clay-lined, with four sites lacking leachate collection systems.
• The EPA identifies Wisconsin as having the most documented coal ash contamination sites in the U.S., listing 11 specific sites. Earthjustice, the Environmental Integrity Project, and the Sierra Club documented two additional sites, including the Columbia Energy Center and the Oak Creek Power Plant, where molybdenum contaminated twelve private drinking wells.
• On October 31, 2011, a bluff collapse at the We Energies Oak Creek Plant caused coal ash and debris to enter Lake Michigan. The ash had been used to fill a ravine over 50 years prior, illustrating a broader state issue regarding unmonitored and unidentified old disposal sites.
• Wisconsin's coal ash recycling rate is at least 85%, which is more than double the average rate of 36% in other states, driven by high disposal costs and relatively stringent disposal regulations. However, regulatory gaps remain, such as discretionary groundwater monitoring at landfills, a lack of specified well locations and numbers, no specified post-closure monitoring period, and no requirement for daily cover.

APA

Earthjustice (n.d.). COAL ASH DISPOSAL AND REUSE IN WISCONSIN. https://earthjustice.org/wp-content/uploads/wi-coal-ash-factsheet-1111.pdf

Chicago

Earthjustice. COAL ASH DISPOSAL AND REUSE IN WISCONSIN. n.d. https://earthjustice.org/wp-content/uploads/wi-coal-ash-factsheet-1111.pdf.

Wikipedia

{{cite report |author=Earthjustice |title=COAL ASH DISPOSAL AND REUSE IN WISCONSIN |url=https://earthjustice.org/wp-content/uploads/wi-coal-ash-factsheet-1111.pdf |access-date=17 August 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{earthjusticendcoal, author = {{Earthjustice}}, title = {{COAL ASH DISPOSAL AND REUSE IN WISCONSIN}}, institution = {Earthjustice}, url = {https://earthjustice.org/wp-content/uploads/wi-coal-ash-factsheet-1111.pdf}, urldate = {2026-08-17}, note = {Indexed by Climate Insights Directory} }