Agency of Natural Resources explains Advanced Clean Cars 2 adoption, compliance options and enforcement to House Transportation

Rachel Stevens of the Vermont Agency of Natural Resources told the House Transportation Committee on Tuesday that Vermont adopted Advanced Clean Cars 2 as part of a package of vehicle‑emissions rules in 2022 and that the rule is designed to reduce greenhouse gases and criteria air pollutants from light‑duty vehicles by requiring manufacturers to provide a rising share of zero‑emission vehicles (ZEVs) and by tightening emissions controls on internal combustion engines.

Stevens said Vermont adopted California’s vehicle regulations under authorities in the Federal Clean Air Act and that the rules were recommended in the state’s climate planning process following the Global Warming Solutions Act. She said agency staff held an extensive public engagement process during the 2022 rulemaking and provided committee members with the administrative record, including technical support documents and responses to public comments.

Deirdre Ritzer, Mobile Sources Section Chief at the Department of Environmental Conservation, described how the rule works: it sets increasingly stringent manufacturer deliverables for model years beginning in 2026 and imposes both tighter emissions standards on combustion engines and a ZEV sales requirement. Ritzer explained that the 2026 ZEV sales requirement starts at 35% but that manufacturers have multiple compliance pathways, including banked credits, early‑compliance credits, environmental‑justice credits (for selling discounted vehicles to qualifying programs), and the ability to transfer credits across states and manufacturers.

Ritzer said those flexible options can reduce a manufacturer’s 2026 obligation substantially — "by as much as 70%" in combined scenarios — which, she said, could bring an effective 35% requirement down to about 11% for a given manufacturer depending on credit use and trading. She emphasized the agency does not set credit prices; credit trading is a market transaction between manufacturers and the agency tracks credit reports for compliance.

Committee members asked about enforcement and penalties. A senator asked what the minimum fine would be if a manufacturer failed to meet delivery requirements. ANR staff answered that enforcement is governed by state statute (Title 10 provisions cited in the discussion) and that the agency’s practice prioritizes compliance through outreach and education; manufacturers are afforded a three‑year make‑up period for missed model‑year targets and any enforcement penalties would be determined case‑by‑case using statutory factors and maximum penalty limits set in statute.

Stevens also explained practical implementation details: DMV registers only California‑certified vehicles in Vermont by checking the manufacturer’s certificate of origin, and the state has used this registration process since the program’s earlier iterations dating to 1996. ANR staff told the committee that ZEV market share in Vermont is already growing and that, in calendar year 2024, direct ZEV sales in Vermont were exceeding milestones under the older Advanced Clean Cars 1 program.

ANR staff provided committee members with the agency’s technical support document, economic and environmental analyses, and the formal responses to public comments submitted during the 2022 rulemaking. They said they are available to return to the committee to discuss Advanced Clean Trucks or other related rules.

No committee action was taken; the session was informational and included a question‑and‑answer exchange about compliance flexibility and enforcement processes.