The Environmental Protection Agency (EPA) is finalizing revisions and confidentiality determinations for the petroleum and natural gas systems source category and the general provisions of the Greenhouse Gas Reporting Rule. These revisions include changes to certain calculation methods, amendments to certain monitoring and data reporting requirements, clarification of certain terms and definitions, and corrections to certain technical and editorial errors that have been identified during the course of implementation. This action also finalizes confidentiality determinations for new or substantially revised data elements contained in these amendments and revises the confidentiality determination for one existing data element.