Researched by Industrial Info Resources (Sugar Land, Texas)--The U.S. Environmental Protection Agency (EPA) is cracking down on toxic waste from coal-fired power plants. Last week, the agency said it would seek safer management of coal combustion residuals, better known as "coal ash," dumped at or near shuttered coal-fired power plants across the country. If adopted, the rule could force utilities and companies in areas currently unregulated by federal authorities to clean up the toxic substance to prevent contamination of groundwater.

Industrial Info is tracking more than $10 billion worth of ash-pond closure projects across the U.S., about $4.5 billion of which is attributed to projects already underway. In 2015, the Obama administration's EPA issued a rule required leaking, unlined coal ash impoundments to initiate closure and stop receiving waste. But the rule made an exception for "legacy" ponds and landfills tied to coal-fired plants that already had retired before the rule took effect.

Companies featured: Salt River Project, Duke Energy Corporation (NYSE:DUK) and Southern Company (NYSE:SO).