EPA’s final emission rules on boilers, and solid waste incinerators, announced in December, have been significantly modified since originally proposed in March 2011 due to the complexity of the types of boilers and fuels used. The rules set pollution emission limits.
When first proposed, a large number of boilers within the U.S., including those at county facilities, would have fallen under the rule. Now, of the 1.5 billion boilers in the U.S. less than 1 percent would need to meet numerical standards, while 13 percent would need to follow certain work practices such as annual tune-ups.
Definition of Boiler Classes
Rules may vary depending on the class or subcategory of the boiler. The two subcategories of most interest to counties are major-source and area-source facilities.
A major-source facility emits 10 or more tons per year of any single air pollutant or 25 tons or more per year of a combination of pollutants. Major-source boilers can be found in industrial facilities such as paper mills or refineries. They can also be found in commercial facilities such as universities or warehouses.
An area-source facility releases 10 or fewer tons of a single air pollutant per year and less than 25 tons of any combination of air pollutants. Many of the boilers covered by the area-source rule can be found at commercial and industrial facilities such as apartments, restaurants, malls, hospitals, nursing homes, schools and municipal buildings. Not covered by the rule are area-source boilers running on natural gas. These account for a significant proportion of the country’s boilers — 1.3 million according to EPA estimates.
Subsequently, the area-source standard covers approximately 183,000 boilers located at 92,000 area-source facilities. Of the 183,000 covered units, approximately 182,400 (more than 99 percent) need only to conduct periodic tune-ups, and some of these also need to perform a one-time energy assessment. Approximately 600 coal-burning units that represent the largest of these sources, are required to meet emission limits.
Commercial and Industrial Solid Waste Incineration Units
Under the Clean Air Act (CAA), Section 129 requires emission standards for nine pollutants from incinerators. Both large and small sources fall under the same requirements. The nine regulated pollutants include: cadmium, carbon monoxide, dioxins and furans, hydrogen chloride, lead, mercury, oxides of nitrogen, particulate matter and sulfur dioxide.
Commercial and industrial solid waste incineration units are used to burn solid waste at an industrial or commercial facility. This includes units used to dispose of solid waste, energy recovery units, waste-burning kilns and small remote incinerators.
The final rule affects 106 existing sources located at 76 facilities. The EPA projects an additional incinerator and five additional small remote incinerators to be subject to this rule over the next five years.