EPA lowers proposed emission limits for chrome electroplating facilities
In a February 8, 2012, Supplemental Notice of Proposed Rulemaking (the supplemental amendment), the EPA proposed to tighten limits in the National Emission Standards for Hazardous Air Pollutants (NESHAP) for Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks and for Steel Pickling-HCL Process Facilities and Hydrochloric Acid Regeneration Plants. See 77 Fed. Reg. 6628 (2/8/12). The EPA had originally proposed revisions to this NESHAP on October 21, 2010 (the original amendment). See 75 Fed. Reg. 65068 (10/21/10). The supplemental amendment was prompted by a new technology review and residual risk analysis performed in response to comments on the original amendment.
The current NESHAP for chromium electroplating was promulgated on January 25, 1995 (60 Fed. Reg. 4963) and is found at 40 CFR Part 63, Subpart N. This NESHAP regulates emissions of chromium compounds from a number of different sources: large hard chromium electroplating, small hard chromium electroplating, decorative chromium electroplating, and chromium anodizing. Large hard chromium facilities are those with a cumulative rectifier capacity at or above 60 million ampere-hours per year (amp-hr/yr); small hard chromium facilities are all those below 60 amp-hr/yr. In the original amendment, the EPA did not require any additional controls on emissions or change emission limits because it “had not identified additional controls that would reduce risk at reasonable costs.” However, because of a concern over residual cancer risk, the EPA initially proposed new housekeeping practices, phased out the use of wetting agent fume suppressants (WAFS) based on perfluorooctyl sulfonates (but not other WAFSs), revised startup, shutdown and malfunction provisions, and revised monitoring and testing requirements. The EPA is not taking additional comments on these issues in connection with the supplemental amendments.
Based on its new data collection and analysis, the EPA is now proposing to lower the current emission control limits for the chromium electroplating category. This decision was based primarily on the fact that the new data show that “most facilities were operating well below the current emission limits,” thus indicating “that more stringent emissions limits could be implemented without significant economic burden to the industry.” The EPA has proposed three alternative compliance options for each category as shown here:
The two surface tension options are applicable only if the facility uses a WAFS in its tanks.
Using the above limits, the EPA estimated that the cancer risk to the individual most exposed to hexavalent chromium emissions “is well below 100-in-1 million,” noting that “100-in-1 million is generally considered the upper limit of acceptable risk.” The EPA further stated that the actual cancer incidence is estimated to be “less than 0.05 cases per year (about 1 case in every 20 years).” It is expected that the supplemental amendment will cut hexavalent chromium emissions by an additional 208 pounds per year and chlorine emissions by an additional 15 tons per year, and will cost industry in the neighborhood of $3.7 million to implement and will add $3.1 million per year in annual costs.
In addition to addressing chromium electroplating, the supplemental amendment also addressed emissions from hydrochloric acid regeneration plants at steel pickling facilities. Under the proposal, the EPA will no longer allow such facilities to use site-specific chlorine concentration standards.
The comment period on the EPA’s supplemental notice closed on March 26, 2012.