On July 16, 2009, the WCI published the Final Essential Requirements for Mandatory Reporting (the "ERs") to be implemented by the WCI Partner jurisdictions. On September 22, 2009, the U.S. EPA adopted its final Mandatory Reporting Rule (the "EPA rule") for greenhouse gas emissions. Many U.S. facilities in the WCI region will be subject to both reporting programs.

The WCI Partners were concerned that the existence of two different reporting systems in a WCI state could result in the imposition of duplicative or conflicting reporting obligations on facilities subject to both programs. The Partners therefore directed the WCI Reporting Committee to develop amended ERs that are harmonized with the EPA rule.

This document and its appendices contain the WCI's proposal for harmonizing the ERs and the EPA rule in U.S. jurisdictions. It takes the form of a markup of the EPA rule showing the changes to the EPA program that are needed to support a cap-and-trade program. The WCI anticipates that WCI jurisdictions in the U.S. will implement the harmonized ERs by adopting a rule that incorporates the EPA rule by reference with the changes shown in the markup.

The WCI is also working on the development of amended ERs that are methodologically consistent with the harmonized ERs but appropriate for use in the Canadian Partner jurisdictions.