Science Module: Stream Ecology
CCR, or coal ash, are the particles left behind from the production of coal-fueled power plants, and can vary in chemical compositions, mostly containing aluminum, calcium, and silica oxides and well as heavy metals such as lead and arsenic. Coal ash may be recycled in “beneficial use,” and can be added as an ingredient to concrete and gypsum products. However, the heavy metals contained in coal ash can contribute to a variety of human health hazards, such as respiratory illness (e.g., asthsma), cell death, and cancer. A report published by the Healthy Energy Initiative concluded that “air pollution from coal plants…causes abnormal neurological development in children…and cancer.” Similarly, a report by Physicians for Social Responsibility states that “coal ash toxics have the potential to injure all of the major organ systems, damage physical health and development, and even contribute to mortality.”
When coal ash is produced from coal power plants, it must be transported to a nearby pond or small body of water for storage and cleanup. However, CCR ponds are not impervious to leakage and surrounding communities may be exposed to hazardous materials in their water, air, and soil. In 2010, the journal Environmental Science and Technology published a report by Duke University scientists detailing the environmental impacts of the coal ash spill in Kingston, Tennessee over 18 months. This research team concluded that the reactive arsenic in coal ash was particularly toxic for surrounding ecosystems, causing death and mutation of plant and wildlife populations that live nearby.
The most common way that companies are proposing to reinforce lined or unlined coal ash disposal sites that are leaking is through capping. The capping process involves the installation of multiple layers of protective materials over the top of pits with coal ash, including a synthetic barrier, drainage layer, soil later, topsoil layer, and vegetation. These capped pits should also have groundwater monitoring wells placed nearby to assess pollution movement. From 2014 EPA data, there are over 1400 coal ash waste storage locations in the US, 331 of which have been rated as “High and Significant” hazard.