Among its myriad rules, the U.S. Environmental Protection Agency’s (EPA) Subpart W in its Greenhouse Gas Reporting Program (GHGRP) presents extra-persnickety details regarding federal emissions reporting for upstream and midstream operators.

Under Subpart W, which contains a threshold of 25,000 metric tons per year of CO2, not to be exceeded, gathering and boosting, and gas transmission become more complex designations.

Subpart W is one of 29 subparts to the GHGRP. The final rule for the petroleum and natural gas systems category of the GHGRP became effective Jan. 1.