The Role Of Emission Factors In permitting And Enforcement

摘要

Facilities preparing to meet new Clean Air Act requirements must also wrestle with the application of emission factors in permits and Clean Air Act compliance determinations. AP-42 emission factors are fraught with errors and uncertainties that create risks for companies relying on them. An analysis of air permitting experience reveals that problems have been addressed on a case-by-case basis and with regulatory and enforcement discretion. However, with more comprehensive permit and monitoring requirements, facilities must recognize the appropriate use of emission factors or remain potentially liable for significant noncompliance. Issues that should be examined include use of emission factors (1) to determine major source status and applicability; (2) to establish permit limits; and (3) to demonstrate and assert noncompliance. The application of "credible evidence" for compliance determinations under EPA's Compliance Assurance Monitoring rule raises the question of the role of emission factors in compliance demonstrations and enforcement. This paper concludes that companies should exercise caution when using emission factors in permitting and compliance determinations. While improvements in emissions calculation techniques will reduce the risk for companies, additional permit and enforcement guidance on these issues could reward due diligent efforts made by companies.