Green Car Congress: EPA Proposes New Emissions Standards Reducing Air Toxics from Vehicles

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EPA Proposes New Emissions Standards Reducing Air Toxics from Vehicles

2 March 2006

The US Environmental Protection Agency (EPA) is proposing standards to reduce hazardous air pollutants from mobile sources. Hazardous air pollutants, also known as air toxics, include benzene and other hydrocarbons such as 1,3-butadiene, formaldehyde, acetaldehyde, acrolein, and naphthalene.

The proposed standards would significantly lower emissions of benzene and the other air toxics in three ways: (1) by lowering benzene content in gasoline; (2) by reducing exhaust emissions from passenger vehicles operated at cold temperatures (lower than 75 degrees); and (3) by reducing emissions that evaporate from, and permeate through, portable gasoline containers.

Once the proposed Mobile Source Air Toxic (MSAT) standards are fully implemented in 2030, they are expected to reduce emissions of mobile source air toxics annually by 350,000 tons, including 65,000 tons of benzene. The estimated annual cost for the entire proposal would be $205 million. EPA estimates annual health benefits from the particulate matter reductions of the vehicle standards to total $6 billion in 2030.

The proposal would also harmonize federal and California evaporative emission standards for light duty vehicles. The proposed MSAT standards would take effect in 2011 for fuel requirements, 2010 for passenger vehicles, and 2009 for fuel containers.

MSATs are known or suspected to cause cancer or other serious health or environmental effects. Benzene is a known carcinogen; most of the nation’s benzene emissions come from mobile sources.

Many MSATs are part of a larger category of mobile source emissions known as volatile organic compounds (VOCs), which contribute to the formation of ozone and possibly particulate matter (PM).

The proposed regulations require refiners to meet an annual average gasoline benzene content standard of 0.62% by volume on all their gasoline, both reformulated and conventional, nationwide beginning in 2011. The national benzene content of gasoline today is about 0.97%. (Gasoline sold in California would not be covered because California has already implemented more stringent standards similar to those EPA is proposing.)

EPA is proposing a nationwide averaging, banking, and trading program as part of the average standard.

For vehicles, the new standards target the reduction of non-methane hydrocarbon (NMHC) exhaust emissions from new gasoline-fueled passenger vehicles. NMHCs include many mobile source air toxics, such as benzene.

EPA is proposing a new cold temperature test where passenger vehicles be subject to an NMHC exhaust emissions standard. Each manufacturer’s vehicles would be subject to a sales-weighted fleet average NMHC level of 0.3 grams/mile for lighter vehicles weighing 6,000 pounds (lbs) or less.

Vehicles above 6,000 lbs (which include trucks up to 8,500 lbs and passenger vehicles up to 10,000 lbs) would be subject to a sales-weighted fleet average NMHC level of 0.5 grams/mile. The standard would phase in between 2010 and 2013 for the lighter vehicles, and between 2012 and 2015 for the heavier vehicles. A credit program and other provisions would provide flexibility to manufacturers, especially during the phase-in periods.

Proposed Cold Temperature NMHC Standard and Phase–In Schedule
Vehicle Weight Class	NMHC Emission Level g/mile	Phase-in Schedule (%)
Vehicle Weight Class	NMHC Emission Level g/mile	2010	2011	2012	2013	2014	2015
<6,000 lbs	0.3	25	50	75	100
6,000–8,500 lbs, plus passenger vehicles up to 10,000 lb	0.5			25	50	75	100

EPA is also proposing more stringent evaporative emission standards for new passenger vehicles equivalent to California’s standards. The agency proposes implementing the evaporative emission standards in 2009 for lighter vehicles and in 2010 for the heavier vehicles.

Finally, EPA is proposing standards that would limit hydrocarbon emissions that evaporate from or permeate through gas cans to 0.3 grams of hydrocarbons per gallon per day.

EPA estimates the following costs associated with the program:

An average $0.0013 per gallon of gasoline. This per-gallon cost would result from an industry-wide investment in capital equipment of $500 million to reduce gasoline benzene levels, or an average of $5 million in capital investment in each refinery that adds such equipment.
A cost to vehicle manufacturers of less than $1 per vehicle. The costs would be associated with vehicle research and development and recalibration, as well as facilities upgrades to handle additional development testing under cold conditions.
An average additional cost of less than $2 per gasoline can. The reduced evaporation from gas cans would result in fuel savings over the life of the can that would more than offset the increased cost for the gas can, according to the EPA.

A 60-day public comment period will begin when the proposal is published in the Federal Register.

March 2, 2006 in Emissions | Permalink | Comments (1) | TrackBack (0)