c. Wetting Agent Fume Suppressants (WAFS)

. The MACT standard allows the use of WAFS as a compliance alternative for meeting the applicable emission limit. WAFS are used in most decorative chromium electroplating and chromium anodizing tanks and in many hard chromium electroplating tanks for emission control. Historically, the most effective types of WAFS have been based on perfluorooctyl sulfonate (PFOS). The PFOS-based WAFS used in the chromium electroplating industry are part of a family of chemical compounds categorized as long-chain perfluorinated chemicals (PFC). As noted in a 2010 California Office of Health Hazard Assessment report, Perfluorooctane sulfonate (PFOS) and Its Salts and Transformation and Degradation Precursors , 2 these compounds have persistent, bioaccumulative, and toxic characteristics and are a particular concern for children’s health. Although it has not been demonstrated that these compounds cause adverse effects to humans, studies have shown significant adverse effects to laboratory animals, wildlife, and groundwater. Over the last several years there have been developments associated with the use of WAFS as a compliance alternative. There are now several types of WAFS on the market that do not

2 This report is available at http://www.oehha.org/prop65/CRNR_notices/pdf_zip/070910_PFOS_CIC.pdf Comment [cjh1]: Suggest deletion, since that SAB report does not make reference to the health effects of PFOS. The report is about PFOA. Deleted: a 2006 EPA SAB report, SAB Review of EPA’s Draft Risk Assessment of Potential Human Health Effects Associated with PFOS and Its Salts 1 and also in

Comment [cjh2]: Can you please provide citations?

Deleted: cost-effectiveinclude PFOS chemicals and have been proven effective for use in hard chromium and decorative chromium electroplating baths that we believe are cost-effective . Furthermore, these non-PFOS WAFS are not associated with any known adverse health effects. Although the non-PFOS WAFS have not been used extensively in the chromium anodizing industry, we are not aware of any technical reasons to preclude their use and effectiveness for chromium anodizing baths. However, we seek comment on this, as well as on our assessment that their use is cost-effective. Because of the adverse non-air quality health and environmental impacts associated with using PFOS-based WAFS (i.e., concern over the presence of long-chain PFC in the environment), we are proposing under CAA section 112 (d)(6) to revise the scope of thecompliance alternative to no longer allow the addition of PFOSbased WAFS to tanks as a control method for these source categories. We solicit comment on all aspects of this change, including the non-air quality health and environmental impacts associated with using PFOS based WAFS. For new sources, we are proposing that no PFOS-based WAFS could be used effective upon startup. For existing sources, we are proposing that no PFOS-based WAFS could be added to the electroplating or anodizing tanks beginning 3 years after promulgation of the final amendments; however, the tanks may continue operating with the remaining PFOS-based WAFS in them Deleted: the increasingafter that date until it is depleted. Under these amendments, these requirements would be specified in 40 CFR 63.342(c)(1)(iv) and (2)(vi) for hard chromium electroplating tanks, 40 CFR 63.342(d)(3) for decorative chromium electroplating and chromium anodizing tanks, and 40 CFR 63.342(e)(2) for decorative chromium electroplating tanks that use a trivalent chromium bath. A definition of PFOS-based fume suppressants also would be added to 40 CFR 63.341.