Greenhouse Gas Emissions Reporting from the Petroleum and Natural Gas Systems - Background Technical Support Document

Country / jurisdiction: United States · Year: 2010 · Status: In force · Level: National · Type: Voluntary

This document provides detailed guidance about how to include petroleum and natural gas facilities in an annual emissions reporting under the U.S. national Greenhouse Gas Reporting Rule. The document was initially prepared by the U.S. EPA as it contemplated adding these sources to the reporting rule requirements. It might be a useful document for other jurisdictions considering a mandatory reporting rule of methane sources in the oil and gas sector.

The document describes covered emissions from oil and gas facilities as falling into two categories: emissions from combustion, and emissions from equipment leaks and vented emissions.

The document describes industry segments and sources of emissions that are "feasible for inclusion in a GHG reporting rule."

The document also explains the U.S. EPA's concern that emission factors in place since the 1990s were under-estimating methane emissions from the oil and natural gas sector: well venting for liquids unloading; gas well venting during well completions; gas well venting during well workovers; crude oil and condensate storage tanks; centrifugal compressor wet seal degassing venting; scrubber dump valves; onshore combustion; and flaring. Therefore, this document adjusts these emission factors and explains the basis for the adjustments. It also describes cooperative efforts with the University of Texas to further refine emissions factors.

The document reviews existing emissions monitoring technologies and direct measurement techniques for oil and natural gas facilities, as well as best practices in emissions estimation. It considers cost and accessibility of components, for measurement and leak detection methodologies.

Official source: https://www.epa.gov/sites/production/files/2015-05/documents/subpart-w_tsd.pdf