Site-Specific Compliance Demonstration For Hydrochloric Acid Emissions For Non-Utility Boilers Subject To 40 CFR 63 Subpart DDDDD (Boiler MACT)

摘要

A Site-Specific Compliance Demonstration per 40 CFR 63 Subpart DDDDD, Appendix A forhydrochloric acid (HCl) was completed for a major mid-western university. 40 CFR 63 SubpartDDDDD, also known as the Boiler MACT, requires subject boilers meet HCl emission limits setforth in the rule through stack testing or fuel monitoring. The rule also provides an alternatecompliance demonstration approach for hydrochloric acid, outlined in Subpart DDDDD,Appendix A. This alternate approach offers two methods to determine eligibility for the healthbasedcompliance alternative for HCl: a Look-Up Table Analysis based on a calculated HClequivalentemission rate from all subject sources, and also a Site-Specific ComplianceDemonstration where the facility is eligible if the compliance demonstration indicates that themaximum chronic hazard index (HI) value for HCl and Cl_2 from the subject sources is less thanor equal to 1.0 at locations where people live or congregate. This paper provides details onmethodologies evaluated and includes results of the health-based eligibility demonstration andbasis for evaluation. All of the utility plant boilers at the university are subject to the BoilerMACT. Therefore, all hydrochloric acid and chlorine emissions associated with combustion ofcoal and fuel oil in the subject boilers were included in this demonstration. The EPA-requiredmethodology resulted in a total hazard index of less than 1.0, i.e., the noncarcinogenic effects ofthe individual chemical concentrations and the noncarcinogenic effects of the combinedchemical concentrations are protective of human health. This entailed the use of a fate andtransport model to estimate ambient air concentrations, followed by an exposure assessment andrisk characterization. The approach used to perform this analysis followed the risk assessmentmethodology found in the U.S. EPA/OAQPS Air Toxics Risk Assessment Library, Volume 2,Facility-Specific Assessment (U.S. Environmental Protection Agency, EPA-453-K-04-001B,April 2004).