Q517. Do I have to calculate emissions from operational LNG storage tank venting at LNG storage facilities or LNG import or export terminals?

Q517. Do I have to calculate emissions from operational LNG storage tank venting at LNG storage facilities or LNG import or export terminals? Also, the equipment listed to be surveyed for leaks does not include pressure relief valves, an emissions source listed for other facility types in 98.233(q). Am I required to report these emissions?

A517.  Regarding your first question: sections 98.232(g) and 98.232(h) do no include venting from LNG storage tanks as an emission source; therefore venting emissions from LNG storage tank are not required for LNG storage or for LNG import and export equipment.  However, if the LNG storge tank is blown down to atmosphere, then section 98.232(h) does require reporting.

To answer the second question about pressure relief valves, Sections 98.233(q)(6) and (7) state that emission factors for “…equipment leaks detected from valves, pump seals, connectors, and other” shall be used from Tables W-5 and W-6 in the rule. A pressure relief valve is a special type of valve and falls in the category of "other," so this emission source is included in the leak detection survey and required to be reported.