States, Localities Petition EPA for Tighter HD NOx Standards

June 3, 2016 – Eleven state and local environmental agencies, led by the South Coast Air Quality Management District (SCAQMD) in California, formally petitioned EPA to adopt a significantly stricter nitrogen oxide (NOx) emission limit for heavy-duty trucks – 0.02 grams per brake horsepower-hour (g/bhp-hr), down from the current 0.2 g/bhp-hr.  In their “Petition for Rulemaking to Adopt Ultra-Low NOx Exhaust Emission Standards for On-Road Heavy-Duty Trucks and Engines,” the group cites the huge contribution of heavy-duty truck NOx emissions to elevated levels of ozone as well as other pollution problems, including particulate matter, visibility impairment and eutrophication of water bodies.  In the words of Wayne Nastri, SCAQMD’s Acting Executive Officer, “In order to meet national clean air goals, we need the federal government to adopt more stringent standards for the No. 1 source of smog-forming emissions in our region—heavy-duty trucks …. A tougher federal truck emission standard will benefit air quality not only in the Southland but also in many areas across the country that currently fail to meet clean air standards.”  Among the specific actions the signatories ask EPA to take are the following: 1) Develop a rulemaking for an ultra-low NOx exhaust emission standard of 0.02 g/bhp-hr for onroad heavy-duty engines with a proposal by July 2017 and a final rule by December 31, 2017; 2) require ultra-low NOx engines to meet the 0.02-g/bhp-hr standard by January 1, 2022; 3) if the ultra-low NOx standard is not feasible for certain classes or vocations of vehicles by January 1, 2022, allow for a phase in to the new standard with an interim standard for some engines of not greater than 0.05 g/bhp-hr and with full implementation of the 0.02-g/bhp-hr standard to occur by January 1, 2024; and 4) encourage early development and deployment of the ultra-low NOx standard by developing guidelines under the Diesel Emissions Reduction Act to provide incentives to truck owners to upgrade their engines.  Joining South Coast as co-petitioners are Akron (Ohio) Regional Air Quality Management District; Bay Area (California) Air Quality Management District; Connecticut Department of Energy and Environmental Protection; Delaware Department of Natural Resources and Environmental Control, Division of Air Quality; New Hampshire Department of Environmental Services; New York City Department of Environmental Protection; Pima County (Arizona) Department of Environmental Quality; Puget Sound (Washington) Clean Air Agency; Washington State Department of Ecology, Air Quality Program; and Washoe County (Nevada) Health District, Air Quality Management.  The petitioners also provided various documents and other materials in a set of attachments to the petition.