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What is Coal Ash?

The Problem

On November 28th, 2019, a report revealed dangerous concentrations of coal ash pollution in the groundwater at 22 of 24 reporting coal ash dump sites in Illinois.

Coal ash is a solid bi-product of burning coal for electricity. Coal ash contains concentrated amounts of the heavy metals and minerals naturally found in coal – including arsenic, boron, lead, mercury, selenium, chromium, and cadmium. These contaminants can inflict severe harm, including brain damage, cancer, learning disabilities, birth defects, and reproductive defects.

At most coal-fired power plants, the coal ash that remains after burning coal is dumped into large coal ash ponds. A coal ash pond is a human-made pond surrounded by a dam where coal ash is dumped to settle out of the wastewater stream. The coal ash is then stored in these ponds for their entire operating life – often decades. Many of these ponds are not lined – the ash is setting directly on the soil below the pond. The coal ash contaminated water can seep into the soil, polluting the groundwater.

For the first time in 2018, utilities were forced to publicly report groundwater monitoring data on their website because of new transparency requirements imposed by 2015 federal coal ash regulations.

The finding that almost 90 percent of Illinois' coal-fired power plants have contaminated groundwater places Illinois at a crossroads:


Will we address the widespread pollution of our aquifers and protect drinking water and nearby lakes and rivers? Or will we continue to allow this toxic contamination to flow in perpetuity?

Other Ways to Stay Connected

Follow for the latest updates on Illinois Coal Ash

Learn more about this issue, view a map of affected sites, and watch video testimonials from impacted communities

View a one-page fact sheet

Read the full report on coal ash groundwater contamination in Illinois (issued by Environmental Integrity Project, Earthjustice, Prairie Rivers Network, and Sierra Club).

Read testimonies from community members who are affected by coal ash contamination in this blog post

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