The Environmental Protection Agency is finalizing revisions and confidentiality determinations for the petroleum and natural gas systems source category of the Greenhouse Gas Reporting Program. In particular, this action adds new monitoring methods for detecting leaks from oil and gas equipment in the petroleum and natural gas systems source category consistent with the fugitive emissions monitoring methods in the recently finalized new source performance standards for the oil and gas industry. This action also adds emission factors for leaking equipment to be used in conjunction with these monitoring methods to calculate and report greenhouse gas emissions resulting from equipment leaks. Finally, this action finalizes reporting requirements and confidentiality determinations for nine new or substantially revised data elements contained in these amendments.