Press Release: 2024-11-06

MassDEP adjusts emissions rules for medium- and heavy-duty trucks

 

In an Oct. 18 letter to stakeholders, the Massachusetts Department of Environmental Protection announced changes to emissions regulations affecting medium- and heavy-duty trucks — the Heavy-duty Omnibus and Advanced Clean Truck rules.

MassDEP said it plans to file emergency regulations to delay the start of the Heavy-duty Omnibus rule until model year 2026, effective upon filing.

The department also indicated that it will exercise enforcement discretion under the Advanced Clean Truck regulation exempting state and local government vehicles used for snow plowing and removal and street sweepers for model years 2025 and 2026.

The MMA has been working with MassDEP to help ensure a full understanding of the requirements and implications of the Heavy-duty Omnibus and Advanced Clean Truck rules. The MMA and many stakeholders have requested a two-year delay to the effective date of both regulations.

Background

The state of California has special authority to set its own vehicle emission standards, as long as the standards are at least as protective as federal emissions standards. Other states are allowed to adopt the California standards as long as the standards are identical to California’s.

MassDEP adopted California’s Low Emission Vehicle program more than 30 years ago, in 1991, and the ongoing adoption of California’s vehicle emissions standards were codified through the Massachusetts Clean Air Act (Ch. 111, Sec. 142K).

In December 2021, MassDEP adopted California’s Heavy-duty Omnibus and Advanced Clean Truck regulations in 310 CMR 7.40.

Heavy-duty rules

The Heavy-duty Omnibus regulation requires emissions standards for nitrogen oxides from conventional heavy-duty vehicles that are more stringent than the national standard.

California required compliance with the HDO starting with model year 2024. The regulations have spurred the development of new engine technology for heavy-duty vehicles, but there have been reported shortages of new engines meeting the standards.

Massachusetts was set to require compliance with these standards starting with model year 2025, but MassDEP plans to delay implementation by a year.

MassDEP also plans to adopt California’s 2024 amendments to HDO legacy engine provisions and exemptions from emissions standards for transit buses, emergency vehicles, and military tactical vehicles.

The U.S. Environmental Protection Agency has not yet provided an enforcement waiver, which is required to allow enforcement in states where the HDO has been adopted, but it is anticipated.

Advanced Clean Truck

The Massachusetts Advanced Clean Truck rule requires graduated zero emission vehicle sales percentages for new medium- and heavy-duty on-road vehicles starting with model year 2025 and increasing until model year 2035. Vehicles driven for 7,500 miles or less are classified as new vehicles.

California required compliance with ACT rules starting with model year 2024, with the intent of promoting growth in medium- and heavy-duty zero-emissions technology and the market, while reducing transportation-related emissions.

The ACT rule applies to on-road vehicles weighing 8,500 pounds or more (classes 2b-8). Enforcement is through manufacturer sales reporting, with fines to manufacturers for noncompliance.

In Massachusetts, for model year 2025, the rule requires 7% ZEV sales in classes 2b-3, 11% in classes 4-8; and 7% for tractors classes 7-8.

Emergency vehicles, including fire, police, corrections, and emergency medical service vehicles, both publicly and privately owned but licensed to operate in response to emergency calls, are exempt from ACT requirements. Publicly owned vehicles for forestry departments are also exempt.

Manufacturers are not required to use a particular process to achieve the sales requirements outlined in the ACT rules, but many manufacturers are requiring dealers to prioritize the sale of ZEV vehicles in the affected categories before allowing sales for vehicles equipped with internal combustion engines. This practice would make internal combustion engine vehicles in the affected classes difficult to access in Massachusetts.

For both the HDO and ACT rules, manufacturers may leverage averaging, banking and trading options that allow credits for allowable prior year sales of ZEV and hybrid vehicles, as well as the purchase of ZEV credits to help meet the associated emissions standards and ZEV sales percentage requirements.

Special exemption process

MassDEP announced that it will exercise enforcement discretion to exempt vehicles purchased by state and local agencies for snow plowing, snow removal, and street sweeping purposes from ACT manufacturer compliance requirements for model years 2025 and 2026.

All internal combustion engine truck sales completed as the result of this enforcement discretion will be excluded from a manufacturer’s total Massachusetts sales when determining ACT compliance.

State and local government agencies must submit written requests to MassDEP and manufacturers or their authorized dealerships detailing the make, model, model year, and number of vehicles to be purchased. MassDEP will make a determination as to whether enforcement discretion is allowable for the proposed purchase, and will communicate its decision to the requesting agency and the manufacturer.

Enforcement discretion requests should be sent to Ngoc.Hoang@mass.gov with the subject line “Enforcement Discretion Purchases.”

Questions about the enforcement discretion and the ACT and HDO rules can be directed to Sharon Weber at Sharon.Weber@mass.gov.