EPA’s New Ozone Rule: Part 17

In our previous post, the EPA explained why it found a secondary standard necessary to protect vegetation Indeed, when EPA’s Clean Air Scientific Advisory Committee (CASAC) found out, they strongly objected. I can imagine that a journalist reporting on CASAC would use words like “furious”, “enraged”, “livid.” They let the EPA know in no uncertain terms how they felt as reported in the document National Ambient Air Quality Standards for Ozone, Final Preamble, 2011 (p. 212):

Following the 2008 decision on the O₃ standards, serious questions were raised as to whether the standards met the requirements of the CAA [Clean Air Act — MHK]. In April 2008, the members of the CASAC Ozone Review Panel sent a letter to EPA stating “[i]n our most-recent letters to you on this subject – dated October 2006 and March 2007 – … the Committee recommended an alternative secondary standard of cumulative form that is substantially different from the primary Ozone NAAQS in averaging time, level and form — specifically, the W126 index within the range of 7 to 15 ppm-hours, accumulated over at least the 12 “daylight” hours and the three maximum ozone months of the summer growing season” (Henderson, 2008). The letter continued: “[t]he CASAC now wishes to convey, by means of this letter, its additional, unsolicited advice with regard to the primary and secondary Ozone NAAQS. In doing so, the participating members of the CASAC Ozone Review Panel are unanimous in strongly urging you or your successor as EPA Administrator to ensure that these recommendations be considered during the next review cycle for the Ozone NAAQS that will begin next year” (id.).

Now CASAC is going to really lay into the EPA!

The letter further stated the following views:

The CASAC was … greatly disappointed that you failed to change the form of the secondary standard to make it different from the primary standard. As stated in the preamble to the Final Rule, even in the previous 1996 ozone review, ‘there was general agreement between the EPA staff, CASAC, and the Administrator, … that a cumulative, seasonal form was more biologically relevant than the previous 1-hour and new 8-hour average forms (61 FR 65716)’ for the secondary standard. Therefore, in both the previous review and in this review, the Agency staff and its advisors agreed that a change in the form of the secondary standard was scientifically well-justified.

Unfortunately, this scientifically-sound approach of using a cumulative exposure index for welfare effects was not adopted, and the default position of using the primary standard for the secondary standard was once again instituted. Keeping the same form for the secondary Ozone NAAQS as for the primary standard is not supported by current scientific knowledge indicating that different indicator variables are needed to protect vegetation compared to public health. The CASAC was further disappointed that a secondary standard of the W126 form was not considered from within the Committee’s previously-recommended range of 7 to 15 ppm-hours. The CASAC sincerely hopes that, in the next round of Ozone NAAQS review, the Agency will be able to support and establish a reasonable and scientifically-defensible cumulative form for the secondary standard.” (Henderson, 2008)

Wow! You can almost feel the burning red-hot indignation behind this rhetoric which I suspect was toned down quite a bit. In our next post, we’ll see how the EPA reacted.