Comment submitted by Alaina Forbes
AnonymousSupportBusiness
Summary: Alaina Forbes of PPEI supports the EPA's proposal to postpone the Tier 4 implementation. She further urges the EPA to reevaluate the necessity of Tier 3 and Tier 4 standards, suggesting a return to Tier 2 levels due to high compliance costs and diminishing emission benefits.
My name is Alaina Forbes with PPEI. I support EPA’s proposal to postpone Tier 4 implementation, but I urge the Agency to go further and reevaluate whether Tier 3 and Tier 4 standards remain justified under Clean Air Act §202(a). EPA’s own historical analyses show that the vast majority of targeted NOx and particulate reductions were achieved under Tier 2, while later tiers impose disproportionately higher compliance and maintenance costs for comparatively small incremental emission reductions. EPA should therefore (1) retain the Tier 4 postponement, (2) initiate rulemaking to revert standards to Tier 2 levels, and (3) establish a technology-neutral safe harbor for in-use vehicles that can demonstrate Tier 2- equivalent emissions performance