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EPA continues to compress and weaken the long-standing, scientifically-sound process for reviewing the adequacy of the National Ambient Air Quality Standards (NAAQS). The Clean Air Act requires that EPA review the NAAQS every five years to ensure they adequately protect human health and the environment. Changes to this process under the Trump administration include significant alterations to the make-up of the Clean Air Scientific Advisory Committee (CASAC), an independent committee of experts that assists EPA in reviewing the NAAQS. Trump’s EPA is also altering the current reviews of the Ozone and Particulate Matter (PM) NAAQS.
This post provides a timeline of those changes and the reviews of the Ozone and PM NAAQS. It will be updated to reflect the most recent actions by the agency and key scientific stakeholders. For a more in-depth look at the health impacts of the NAAQS, the importance of the five-year scientific reviews, and the Trump administration’s changes, listen to our CleanLaw Podcasts with Janet McCabe and Gretchen Goldman, and read our posts: The Legal Consequences of EPA’s Disruption of the NAAQS Process and Subverting the Process of Setting Health-Based Air Quality Standards Part 1 and Part 2.
Current Status
April 14, 2020 EPA announces that it is proposing to retain the PM NAAQS. The proposed action is open for comment until June 29, 2020.
July 13, 2020 EPA announces it is proposing to retain the ozone NAAQS. The proposed decision will be open for comment once it’s published in the Federal Register.
Timeline of Changes to the Scientific Process
Oct. 31, 2017 Administrator Pruitt issues a memo changing the membership requirements for CASAC. Under the new guidelines, receiving an EPA grant is now deemed a “conflict of interest.” Scientists who have received grants from EPA are no longer eligible to serve on the committee. Most industry-affiliated scientists are unaffected, but this change disqualifies many academic scientists, including then-serving members of CASAC.
April 30, 2018 EPA publishes a proposed rule, Strengthening Transparency in Regulatory Science. The proposal would require that EPA consider only scientific studies for which the underlying data can be made public. The proposal would significantly limit the studies available to EPA in reviewing the NAAQS, because many epidemiological studies use confidential health information that cannot be made public. EPA receives nearly 600,000 comments on the proposed rule before the comment period closes.
May 9, 2018 Administrator Scott Pruitt signs a Memorandum, Back-to-Basics Process for Reviewing National Ambient Air Quality Standards, which modifies and accelerates the process for reviewing and setting the NAAQS. The memo directs the agency to complete the current reviews of the ozone NAAQS by October 2020 and the PM NAAQS by December 2020. Many experts argue that this schedule is incompatible with the thorough scientific review required by the Clean Air Act, because it does not provide sufficient time.
Oct. 10, 2018 EPA issues a press release tasking CASAC with reviewing the ozone and PM NAAQS, notably eliminating the role of independent review panels that were historically convened to assist CASAC. The PM panelists report receiving a dismissal email from EPA. These expert panels are essential to a robust scientific review, given that CASAC has – by consequence of being a seven-member panel – limited expertise. By this point in time, Trump’s EPA has replaced the entire CASAC, and there is no epidemiologist on the panel.
Feb. 10, 2020 The Southern District of New York holds that EPA violated the law when issuing the conflicts of interest directive and vacates the relevant language. As a result, until EPA modifies its decision or fixes the procedural defects the court identified, EPA cannot categorically prohibit grant recipients from serving on advisory panels. Natural Resources Defense Council, Inc. v. EPA, No. 1:19-cv-05174-DLC.
March 18, 2020 EPA publishes a supplemental notice of proposed rulemaking to amend its 2018 proposed rule, Strengthening Transparency in Regulatory Science.
Review of Ozone NAAQS
Dec. 10, 2018 Three current CASAC members urge EPA to reconvene the Ozone Review Panel in their comments on the draft Integrated Review Plan for Ozone NAAQS.
Aug. 22, 2019 EPA publishes the Integrated Review Plan for the Review of the Ozone NAAQS, which includes a timeline projecting that EPA will finalize the Ozone NAAQS in “Winter 2020/2021,” potentially pushing back the original December 2020 goal. EPA does not include a plan to develop a Risk and Exposure Assessment and instead plans to include the relevant analysis in the Policy Assessment. The Risk and Exposure Assessment is a separate scientific assessment that builds upon the conclusions of the Integrated Science Assessment. EPA has historically made the Risk and Exposure Assessment available for public comment and sought CASAC’s review of the document independently from other assessments.
Sep. 13, 2019 EPA announces the selection of 12 consultants to answer individual questions passed through the CASAC chair from CASAC members regarding the review of the NAAQS for ozone and PM. Later reporting reveals that Administrator Wheeler selected six of the 10 industry affiliated experts nominated for the consulting pool and only six of the 43 academic nominees. The use of consultants, rather than an independent panel, severely reduces transparency and effectiveness of the review process by not allowing for an open debate among and deliberation by experts meeting together.
Sep. 26, 2019 EPA publishes the draft Integrated Science Assessment for Ozone, which will be discussed at the December 2019 CASAC meeting.
Oct. 31, 2019 EPA releases the draft Policy Assessment for the Ozone NAAQS before CASAC has reviewed and sought revisions to the science assessment. The Policy Assessment finds that the newly available evidence continues to support the current ozone NAAQS. The Policy Assessment is also slated for discussion at the December 2019 CASAC meeting.
Dec. 2, 2019 18 former members of the CASAC Ozone Review Panel send a letter to EPA stating that the changes EPA has made to the NAAQS review process “are collectively harmful to the quality, credibility, and integrity of EPA’s scientific review process and to CASAC as an advisory body.” The letter goes on to state that “[t]he NAAQS review for ozone should be suspended until these deficiencies are corrected.”
Dec. 3-6, 2019 CASAC meets to discuss the Integrated Science Assessment and Policy Assessment for Ozone as well as the Policy Assessment for PM. Reviewing the ozone science and policy assessments together decreases the level of review possible by CASAC and departs from the previous long-standing NAAQS process of determining the science before considering policy.
Dec. 6, 2019 CASAC fails to reach consensus regarding the adequacy of the existing ozone NAAQS. Six members endorse retaining the current standards while one member would recommend tightening the standards. CASAC later announces a teleconference on Feb. 11-12 to continue discussing the committee’s recommendations for ozone.
Feb. 12, 2020 CASAC agrees on a final report to Administrator Wheeler recommending no change to the existing ground-level ozone standard. The report also urges EPA to restore the independent ozone review panel and in-person meetings between CASAC and members of the panel.
April 1, 2020 Administrator Wheeler sends a letter to CASAC Chair Tony Cox stating that EPA will stick to its 2020 deadline for the Ozone NAAQS. Wheeler acknowledges that this deadline means many of CASAC’s comments on the Integrated Science Assessment that are “more substantial or cross-cutting” will not be addressed in this review cycle.
May 31, 2020 EPA publishes the final Policy Assessment for ozone, affirming that the most recent scientific evidence continues to support retaining the current ozone NAAQS. The Policy Assessment projects that EPA will publish a proposed decision on retaining or changing the ozone NAAQS in mid-2020.
July 13, 2020 EPA announces it is proposing to retain the ozone NAAQS. The proposed decision will be open for comment once it’s published in the Federal Register.
Review of Particulate Matter NAAQS
Oct. 23, 2018 EPA announces the public comment period for the draft Integrated Science Assessment for PM.
April 11, 2019 CASAC writes a letter to Administrator Wheeler critiquing the Draft Integrated Science Assessment for PM. CASAC recommends three substantive revisions as well as two procedural changes. CASAC advises EPA to develop a Second Draft Integrated Science Assessment for the committee to review and to reappoint the disbanded PM panel. CASAC specifically seeks additional expertise in diverse scientific fields to ensure that “meaningful independent scientific review” can occur.
Sep. 5, 2019 EPA releases the draft Policy Assessment for PM NAAQS. The Policy Assessment states that the available evidence and analyses “can reasonably be viewed as calling into question the adequacy of the public health protection afforded by” the PM2.5 standards.
Sep. 13, 2019 EPA announces the selection of 12 consultants to answer individual questions passed through the CASAC chair from CASAC members regarding the review of the NAAQS for ozone and PM. Later reporting reveals that Administrator Wheeler selected six of the 10 industry affiliated experts nominated for the consulting pool and only six of the 43 academic nominees. The use of consultants, rather than an independent panel, severely reduces transparency and effectiveness of the review process by not allowing for an open debate among and deliberation by experts meeting together.
Oct. 22, 2019 The Independent Particulate Matter Review Panel, which comprises 18 former members of the now-disbanded PM Review Panel, submit consensus recommendations to CASAC ahead of its October meeting. The independent panel recommends tightening the PM NAAQS in order to meet the Clean Air Act standard of adequately protecting public health. This report follows a two-day meeting by the group, which sought to closely mirror the meeting they would have had if EPA had not disbanded the panel.
Nov. 13, 2019 CASAC releases a draft report following its October meetings. The report recommends EPA retain the current PM NAAQS but acknowledges that CASAC did not reach a consensus on this recommendation.
Dec. 3-6, 2019 CASAC meets to discuss the Integrated Science Assessment and Policy Assessment for Ozone as well as the Policy Assessment for PM.
Dec. 3, 2019 CASAC votes to approve an updated version of the Nov. 13 report that recommends EPA retain the current PM NAAQS. The report makes clear that this recommendation does not reflect a consensus among CASAC members, meaning that not all members agree that the current PM NAAQS adequately protect public health.
Dec. 16, 2019 CASAC finalizes its report to Administrator Wheeler on the PM NAAQS. The report confirms that CASAC is divided as to whether the current science calls into question the adequacy of the existing standards, but ultimately, CASAC recommends EPA retain the existing NAAQS.
Jan. 27, 2020 EPA publishes the final 2019 Integrated Science Assessment for PM.
Jan. 29, 2020 EPA releases the final Policy Assessment for PM. The final assessment states that ” the available scientific evidence, air quality analyses, and the risk assessment…can reasonably be viewed as calling into question the adequacy of the public health protection afforded by the combination of the current annual and 24-hour primary PM2.5 standards. In contrast to this conclusion, a conclusion that the current primary PM2.5 standards do provide adequate public health protection would place little weight on the broad body of epidemiologic evidence reporting generally positive and statistically significant health effect associations, particularly for PM2.5 air quality distributions likely to have been allowed by the current primary standards.” This conclusion calls into question CASAC’s recommendation to retain the existing PM NAAQS.
March 4, 2020 EPA sends its proposed decision on whether to maintain the Particulate Matter NAAQS to the Office of Management and Budget for review. This is a required step prior to publishing the guidance.
April 14, 2020 EPA announces that it is proposing to retain the PM NAAQS. The proposed action is open for comment until June 29, 2020.