ENV-03-114 “Apples to Apples” A Consistent Approach to Estimating Potential to Emit for Fugitive Emissions

Description:

Since the inception of the EPA’s Leak-No Leak Protocol and emission factors, fugitive emissions have typically been grossly overestimated. This often leads to a large difference in the "actual to potential" analysis performed for Prevention of Significant Deterioration (PSD) and New Source Review (NSR) permit applications causing permitting problems. Additionally, the use of these very conservative factors does not accurately portray actual emissions from these sources as found when the sources are monitored. This latter point can have a detrimental affect on air shed modeling in areas of ozone non-attainment. In recent years, Leak Detection and Reporting (LDAR) issues and fugitive emissions have risen to the forefront, taking a much higher profile in the environmental arena. Everyone from regulatory agencies, to the public, to the United States Congress, has raised concern over the magnitude of the emissions reported from fugitive components. As MACT standards and state SIP requirements force point source emissions to be reduced, the potential to emit (PTE) of fugitive emissions (as reported) constitute a growing percentage of facility-wide emissions. At this point, many petrochemical and refinery environmental departments have gathered significant fugitive emission data for their facilities based on monitoring programs. Most facilities convert the actual monitoring data to emission rates using EPA correlation factors based on the instrument being used and the compounds monitored. The challenge lies in using actual monitoring data that has been collected to estimate a PTE for permitting purposes. If emissions are underestimated, the facility faces potential problems complying with their permit; if they are overestimated, the facility faces potential NSR and modeling concerns. This paper examines one technique developed to utilize information gathered from a facility’s LDAR program to permit a PTE that does not constrain the facility’s operations, yet provides a more realistic estimate of emissions from fugitive sources.