The EPA is finalizing amendments to the Portland Cement Manufacturing NESHAP to correct and clarify rule compliance requirements and provisions. This action will improve monitoring, compliance and implementation of the rule at no cost to industry. EPA has found that existing air toxics rules for Portland cement manufacturing achieved significant reductions of mercury, acid gases, particulate matter and total hydrocarbons from existing cement kilns across the country, while ensuring that emissions from new kilns remain low. After conducting a risk analysis, EPA has determined that revisions to emissions limits are not necessary at this time.You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.