In February, the U.S. Environmental Protection Agency published proposed rules that seek to implement more stringent emission standards for chromium electroplating and anodizing facilities.
The proposed rules would amend the existing National Emission Standards for Hazardous Air Pollutants Emissions for hard and decorative chromium electroplating and chromium anodizing tanks by lowering the existing NESHAP limits for both existing and new sources.
The EPA accepted public comments on the proposed rules from Feb. 8 until March 26. The comments and revisions to the rule will be released later this year and will be available online at Regulations.gov.
EPA is proposing to lower surface tension levels from 45 to 40 dynes/cm when measured by a stalagmometer, and from 35 to 33 dynes/cm when measured with a tensiometer. EPA’s analysis indicates that many plants using wetting agent fume suppressants (WAFS) are already meeting the revised surface tension limits.
For those who are not currently in compliance, EPA believes that they can easily achieve compliance with a small increase in the use of WAFS. It is important to note that EPA is phasing out WAFS that contain perfluorooctyl sulfonantes (PFOS).
EPA believes that the decrease in surface tension levels will result in emission reductions that correspond with the lower emission limits that are part of the proposed rule.
The revised emission limits will be lower for both existing and new sources. For decorative chromium plating and chromic acid anodizing, the limits will be reduced to 0.007 mg/dscm from 0.01 mg/dscm for existing sources and 0.006 mg/dscm from 0.01 mg/dscm for new sources. For hard chromium plating, the limits are reduced to 0.015 mg/dscm from 0.030 mg/dscm for existing small sources and 0.006 mg/dscm from 0.015 mg/dscm for new small sources.
The proposed rules also reduce the limits to 0.011 mg/dscm from 0.015 mg/dscm for existing large sources and to 0.006 mg/dscm from 0.015 mg/dscm for new large
EPA based the proposed emission limits on industry data for each of the affected source categories. EPA believes that most facilities subject to the existing rules are already operating at or well below the proposed limits. Moreover, EPA believes that maintaining the new, reduced surface tension levels will result in reduced emissions that comply with the reduced emission limits.
EPA’s proposal provides two methods for demonstrating compliance. Those facilities that use emission control equipment to meet new emission standards will need to perform a new performance stack emissions test that is representative of current operations and controls. That test must be conducted at the exit of the control device and must show compliance with the new limits.
In some cases, EPA may accept a previous performance test if it meets all of the requisite criteria. Those facilities that utilize the referenced surface tension limits for compliance can monitor and demonstrate compliance with the surface tension standard to prove compliance.
EPA based its proposed rules on some general industry data, and made some general emissions, risk and cost assumptions based upon that data.
EPA had specifically requested comments from the metal finishing industry on items such as WAFS that do not contain PFOS and the costs and feasibility of using those WAFS. It was also seeking data that will reduce uncertainties in the risk assessment and any other analysis that serve as a foundation for the proposed rules. It was predicted that adversely affected facilities would provide comment on the proposed rules that included relevant data to clarify any faulty EPA assumptions regarding feasibility, cost and risk.
You can read what the NASF has to say about the new rules in the NASF Report on page 12 of this magazine. To get the latest information on the proposed rules, visit Regulations.gov and enter docket number EPA-HQ-OAR-2010-0600.
Anthony J. Giuliani, partner at Vorys, Sater, Seymour and Pease, and member of energy and environment practice group, 614-464-6279.
National Association for Surface Finishing
This paper is a peer-reviewed and edited version of a presentation delivered at NASF SUR/FIN 2012 in Las Vegas, Nev., on June 12, 2012.
I am looking for safety/environmental requirements to set up a nitric acid cleaning and passivation system.
Our expert, Art Kushner, says yes, you can color stainless steel, but it is not a process that is typically performed in a plating shop. Read more about his answer.