Integrated Science Assessment (ISA) For Oxides of Nitrogen, Oxides of Sulfur and Particulate Matter Ecological Criteria (Second External Review Draft, Jun 2018)
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Oxides of nitrogen, oxides of sulfur, and particulate matter are three of six criteria pollutants for which EPA has established NAAQS. Periodically, EPA reviews the scientific basis for these standards by preparing an ISA (formerly called an Air Quality Criteria Document). The ISA, in conjunction with additional technical and policy assessments, provides the scientific basis for EPA’s decisions on the adequacy of the current NAAQS and the appropriateness of possible alternative standards. The intent of the ISA, as described in the Clean Air Act, is to 'accurately reflect the latest scientific knowledge expected from the presence of [a] pollutant in ambient air.' It includes scientific research from atmospheric sciences, exposure and deposition, biogeochemistry, hydrology, soil science, marine science, plant physiology, animal physiology, and ecology conducted at multiple scales (e.g., population, community, ecosystem, landscape levels).
Key information and judgments formerly found in the AQCDs for oxides of sulfur, oxides of nitrogen and particulate matter for ecological effects are included; appendices provide additional details supporting the ISA. Together, the ISA and appendices serve to update and revise the last oxides of nitrogen and oxides of sulfur ISA which was published in 2008 and the ecological portion of the last particulate matter ISA, which was published in 2009.
Additionally, the Clean Air Scientific Advisory Committee (CASAC) is an independent science advisory committee whose review and advisory functions are mandated by Section 109(d)(2) of the Clean Air Act, and charged (among other things) with performing an independent scientific review of all the EPA’s air quality criteria.
|Jun 2018||EPA released the second external review draft for public review and comment. The draft document was then discussed at a CASAC meeting September 5-6. 2018.|
|Mar 2017||EPA released the first external review draft for public review and comment. The draft document was then discussed at a CASAC meeting May 24-25. 2017.|
|Jan 2017||EPA released the final Integrated Review Plan for the Secondary National Ambient Air Quality Standards for Oxides of Nitrogen, Oxides of Sulfur and Particulate Matter.|
|Aug 2015||EPA hosted a multiple teleconference workshops with invited scientific experts, both internal and external to EPA, on August 25, 26 and 27, 2015 (80 FR 48316, August 12, 2015) and June 13, 2016 (81 FR 89262, May 11, 2016) to discuss initial draft materials prepared in the development of the draft ISA.|
|Feb 2015||EPA conducted a workshop on February 11, 2015 (79 FR 71764, December 3, 2014) for particulate matter to gather input from invited scientific experts, both internal and external to EPA, as well as from the public, regarding key science and policy issues relevant to the review of the secondary NAAQS. These science and policy issues were incorporated into EPA's draft of the Integrated Review Plan for the National Ambient Air Quality Standards for Particulate Matter.|
|Dec 2014||On December 3, 2014 (79 FR 71764), EPA formally initiated its current review of the air quality criteria for the particulate matter NAAQS.|
|Mar 2014||EPA conducted a workshop on March 4 to 6, 2014 for oxides of nitrogen and oxides of sulfur (79 FR 8644, February 13, 2014) to gather input from invited scientific experts, both internal and external to EPA, as well as from the public, regarding key science and policy issues relevant to the review of these secondary NAAQS. These science and policy issues were incorporated into EPA's "Draft Integrated Review Plan for the Secondary National Ambient Air Quality Standard for Oxides of Nitrogen and Oxides of Sulfur (draft IRP)".|
|Aug 2013||EPA formally initiated its current review of the air quality criteria for the ecological effects of oxides of nitrogen and oxides of sulfur and the associated secondary (welfare-based) NAAQS, requesting the submission of recent scientific information on specified topics.|
This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.