Q289. The rule states that LDCs need to report under subpart NN if they delivered more than 460,000 thousand standard cubic feet (Mscf) of natural gas during the reporting year. How should an LDC determine if it "delivered" more than 460,000 Mscf? Does this include quantities delivered to other LDCs and/or large end-users? What about natural gas placed into/removed from storage?

A289. According to Table A-5 of Part 98 (Subpart A), local natural gas distribution companies that deliver 460,000 Mscf or more of natural gas per year are subject to the rule. This threshold does not include deliveries to other LDCs or downstream gas transmission pipelines as they are not deemed "end-users". This threshold does cover deliveries to all end users, including those end-users that receive greater than 460,000 Mscf per year.

There are two potential ways that an LDC could calculate whether they surpass the threshold. One option is to add the appropriate delivered volumes of natural gas in 98.406. To determine natural gas "delivered" from the data elements in 98.406 you would take the annual volume in Mscf received by the LDC, subtract the volume placed into storage, add vaporized LNG produced at on-system vaporization facilities for delivery, if not accounted for in (b)(1), add volume of gas withdrawn from on-system storage (that is not delivered to the city gate) for delivery on the distribution system, add gas delivered directly to LDCs from producers or gas processing plants, and subtract gas re-delivered to downstream gas transmission pipelines and other local distribution companies. In summary, total gas delivered would be (b)(1)- (b)(2) + (b)(3) + (b)(4) + (b)(5) - (b)(6).

Alternatively, you could add the emissions calculated using Equation NN-6 and the emissions calculated using Equation NN-4. Please note, however, that the threshold for subpart NN is in terms of Mscf, so you would need to convert the GHG emissions estimate in metric tons back to Mscf to determine applicability.