On April 29, 2010, EPA issued proposed revisions to 40 CFR Part 75. The proposed rule revisions are expected to be published in the Federal Register in the near future. A preliminary version is included in our FTP library. One primary revision is the removal of all requirements for mercury (Hg) continuous emission monitoring systems, including Appendix K for sorbent trap Hg CEMS. Additionally, EPA has reintroduced requirements for Air Emission Testing Bodies (AETB) for conducting relative accuracy test audits (RATAs). EPA has also proposed changes to the Protocol Gas Verification Program designed to improve the accuracy of EPA protocol gases. There will be a 30-day comment period following the publication of the proposed rule in the Federal Register.