NACAA Urges EPA to Tighten Onroad HD NOx Stds

June 21, 2018NACAA sent a letter to EPA Administrator Scott Pruitt urging that he take prompt action to strengthen the NOx emission standards for on-highway heavy-duty trucks and engines.  In the letter, signed by the NACAA Mobile Sources and Fuels Committee co-chairs, Steve Flint (NY) and Erik White (Placer Co., CA), the association explained that 1) tighter NOx standards for heavy-duty trucks will help areas across the country meet their legal obligation to attain, or maintain, the health-based National Ambient Air Quality Standards for ozone; 2)  a stringent, harmonized “50-state” standard is more cost-effective and achieves greater emission reductions than more rigorous regional standards; 3) if EPA does not require sufficient reductions from heavy-duty trucks areas will have to adopt severe limits on local business; 4) the technology for lower-emitting engines is feasible, available and cost-effective; 5) EPA, on December 20, 2016 – in response to a petition submitted by the South Coast Air Quality Management District and co-signed or subsequently supported by 19 state and local air pollution control agencies – committed to a rulemaking to revise the on-highway heavy-duty truck and engine NOx standard; 6) principles of cooperative federalism require prompt and more stringent EPA regulation of mobile sources; and 7) more stringent NOx standards for on-highway heavy-duty trucks would substantially and directly contribute to achievement of one of Administrator Pruitt’s often-articulated top priorities – significantly reducing the number of nonattainment areas.  NACAA also urged that such tighter NOx standards achieve a reduction in emissions on the order of 90 percent and expressed strong interest in working with EPA to develop these important standards.