Q478. Are the emissions factors listed in Table W-1A for both leaking components and non-leaking components? How do you calculate emissions from leaking components if onshore petroleum and natural gas source are not required to monitor components?

A478. Equipment leak emissions in onshore production are to be estimated using methods provided in 98.233(r)(2).  Hence, no leak detection of emissions is required for onshore production.  Table W-1A provides population emission factors, which represent the emissions on an average from the entire population of components – both leaking and non-leaking; please see section 6(d) of the Technical Support Document (http://www.epa.gov/ghgreporting/documents/pdf/2010/Subpart-W_TSD.pdf) for further details on the concept of population emission factors.