In response to federal court orders requiring the issuance of final standards, the U.S. Environmental Protection Agency (EPA) has issued final Clean Air Act standards for boilers and certain incinerators. (Read the EPA rulemaking.)
The rulemaking envisions cutting the cost of implementing the regulations by 50 percent from an earlier proposal, resulting in a projected savings of $1.8 billion from the earlier proposal.
However, the agencyà‚ announced it would “reconsider” the final standards to seek additional public review and comment.
EPA said that because the final standards significantly differ from earlier proposals,à‚ it believes further public review is necessary. EPA said it will reconsider the final standards under a Clean Air Act process.à‚ The agency’sà‚ reconsideration will cover the emissions standards for large and small boilers and for solid waste incinerators.
While the ruling is under reconsideration, the ruling is still considered final, said Lisa Jaeger, partner at Bracewell & Giuliani LLP.
“EPA is saying it will reconsider certain elements of the rule,” Jaegar said. “(EPA Administrator) Lisa Jackson recently said the agency didn’t need more time for the rule-making, which is an indication that they expect a short reconsideration process.”
Randy Rawson, president and chief executive officer of the American Boiler Manufacturers Association (ABMA), said the new rules seem to provide more flexibility in approach and a greater recognition of the many variables associated with boiler operation.à‚ “We are hopeful that any remaining issues with either numeric emissions limits or implementation can be resolved through the reconsideration process,” he said.
EPA will release additional details on the reconsideration process to ensure the public, industry and stakeholders have an opportunity to participate.à‚ For more information, see the reconsideration notice.
The rules set the following emission limits for area source boilers:
à‚·à‚ à‚ à‚ à‚ à‚ à‚ à‚ à‚ For existing coal-fired boilers with heat inputs greater than 10 MMBtu/h, mercury emissions are limited to 0.0000048 lb and carbon monoxide emissions are limited to 400 ppm by volume on a dry basis corrected to 7 percent oxygen.
à‚·à‚ à‚ à‚ à‚ à‚ à‚ à‚ à‚ For new coal-fired boilers with heat inputs greater than 30 MMBtu/hr, the limit for particulate matter is 0.03 lb, for mercury it is 0.0000048 lb and for carbon monoxide it is 400 ppm by volume on a dry basis corrected to 3 percent oxygen.
à‚·à‚ à‚ à‚ à‚ à‚ à‚ à‚ à‚ For new coal-fired boilers with heat inputs that are greater than 10 and less than 30 MMBtu/h, the emissions limit is 0.42 lb for particulate matter, 0.0000048 lb of mercury and 400 ppm of carbon monoxide.
à‚·à‚ à‚ à‚ à‚ à‚ à‚ à‚ à‚ For new biomass-fired boilers that have heat inputs greater than 30 MMBtu/h, the particulate matter limit is 0.03 lb. For boilers with heat inputs greater than 10 but less than 30 MMBtu/h the particulate matter limit is 0.07.
à‚·à‚ à‚ à‚ à‚ à‚ à‚ à‚ à‚ For new oil-fired boilers that have heat inputs greater than 30 MMBtu/h, the limit on particulate matter emissions is 0.03 lb. For boilers greater than 10 and less than 30 MMBtu/h heat input the limit is 0.03 lb.
EPA said the emission limits for mercury and CO apply only to boilers in the coal subcategory; the emission limits for existing area source boilers in the coal subcategory are applicable only to area source boilers that have a designed heat input capacity of 10 million MMBtu/h or greater.
For boilers that burn any liquid fuel and is not in either the coal or the biomass subcategory, the unit is in the oil subcategory, except if the unit burns oil only during periods of gas curtailment.
EPA said it also is requiring all biomass-fired and oil-fired area source boilers to implement a tune-up program as a management practice.
For boilers that burn any solid fossil fuel and no more than 15 percent biomass on a total fuel annual heat input basis, the boiler is in the coal subcategory. For boilers that burn at least 15 percent biomass on a total fuel annual heat input basis, the unit is in the biomass subcategory.
“The final rule does provide some incentive to look at coal-fired with biomass as part of a compliance suggestion,” said Gina McCarthy, assistant administrator for the EPA Office of Air and Radiation.
The ruling ” seemingly in favor of biomass expansion ” follows a January-issued EPA greenhouse gas exemption that provides a three-year reprieve for biomass facilities.
“Facially, some of the changes in this final rule reflect a greater understanding of the value of biomass in the energy mix and the need for flexibility of sources that incorporate biomass,” said Jaeger.
Rawson said the initial Boiler MACT ruling, which did not provide allowances for biomass-fired boilers, had been an area of concern. “Now that has been addressed if not resolved in both changes in CO emissions requirements for biomass-fired area source boilers as well as the new solid-fuel category and the treatment of biomass fuels in general.”
Jaegar said areas that EPA failed to address in the ruling include the neglect to develop an emissions limit that is based on health thresholds. Another area of concern, Jaegar said, is EPA’s definition of non-hazardous materials that are solid waste. One issue that could result from this definition, Jaegar said, is in facilities that retain materials on site and reuse them for fuel. Those materials would be susceptible to a solid waste analysis under the ruling.
While the mandated numeric emissions limits arebeing reviewed and analyzed now by the ABMA, Rawson said he is hopeful that the ruling will be positive for the industry.
“EPA’s expansion of work-practice standards in lieu of numeric limits, its creation of a solid-fuel category, its recognition of limited-use boilers and its acceptance of work-practice standards in lieu of numeric limits for periods of startup and shutdown go a long way in bringing greater practicality and pragmatism to the mix, not to mention much-reduced costs of compliance.”