EPA Approves Texas Waiver Expanding Low-Sulfur Diesel Use

EPA Expands E15 Waiver to More Light-Duty Vehicles, but Heavy-Duty Trucks Remain Excluded

The U.S. Environmental Protection Agency expanded approval for gasoline containing up to 15% ethanol, known as E15, to include model year 2001 through 2006 passenger vehicles. The decision followed an earlier waiver covering model year 2007 and newer cars and light trucks.

For professional drivers and fleet operators, the most important point is what the waiver does not cover: E15 remains excluded from vehicles with heavy-duty engines, including delivery trucks, school buses and transit buses. It also is not approved for motorcycles, boats, snowmobiles or engines used in off-road equipment such as lawnmowers and chain saws.

The EPA’s January 2011 action followed additional Department of Energy testing on E15’s emissions performance in model year 2001 through 2006 cars, sport utility vehicles and light pickup trucks. In October 2010, the agency had approved E15 for model year 2007 and newer cars and light trucks, while delaying a decision on older vehicles.

At that time, the EPA said there was not enough testing data to support E15 use in model year 2000 and older cars and light trucks. The agency also continued to withhold approval for heavy-duty vehicles and non-road engines because available testing did not support extending the waiver to those applications.

What the waiver means

E15 contains more ethanol than the E10 gasoline blend that had traditionally been approved for conventional cars and light trucks. The waiver allows the sale of gasoline containing up to 15% ethanol for the specified model years, but it does not automatically authorize every vehicle or engine to use the fuel.

The EPA’s decision was made under a provision of the Clean Air Act covering significantly altered fuels. Growth Energy and 54 ethanol manufacturers submitted the original petition in March 2009. Under that provision, a waiver may be granted if the petitioner demonstrates that the fuel will not cause or contribute to failures in engine components needed to meet emissions standards.

The agency reviewed DOE testing and other available information on emissions and engine durability before granting the two waivers. Automakers opposed the expansion, arguing that additional testing was needed to evaluate the effects of E15 on model year 2001 through 2006 vehicles.

Approval also came with conditions related to fuel quality and emissions. Ethanol used in E15 must meet the applicable ASTM purity specifications for ethanol blended with gasoline. During the summer, E15 is subject to a Reid Vapor Pressure limit of 9.0 pounds per square inch. The waiver also requires testing to evaluate possible adverse health effects associated with E15 emissions.

Why the limits matter to truck operators

The waiver does not change the fuel requirements for heavy-duty trucks. A tractor, straight truck, delivery vehicle or other vehicle equipped with a heavy-duty engine is outside the approved use of E15, regardless of whether it operates on local routes or long-haul lanes.

That distinction is important because fuel pumps may offer several gasoline and diesel products, and E15 is intended for certain light-duty gasoline vehicles only. The EPA proposed new pump-labeling requirements to help consumers identify the ethanol content of gasoline and select the correct fuel for their vehicles and equipment.

Using a fuel outside the approved application can create equipment and compliance concerns. Ethanol can absorb moisture more readily than gasoline, and exposure to ethanol blends may affect fuel-system materials that were not designed for higher ethanol concentrations. Components such as rubber seals, fuel lines, injectors, pumps, polymers and pipe sealants may be vulnerable, particularly in older or incompatible equipment.

Corrosion concerns also extend to fuel-storage systems. Zinc and other soft metals can be susceptible to corrosion when exposed to ethanol blends. Tank components, underground storage tanks and related fittings may face added risk if corrosion or phase separation occurs. A release from a damaged storage system could also create environmental problems.

These concerns are one reason the waiver includes strict vehicle and equipment exclusions. The approval is not a blanket authorization for E15 in all gasoline engines, and it does not apply to diesel fuel or to trucks equipped with heavy-duty engines.

Commercialization still requires additional steps

The EPA described the waivers as only part of the process needed to commercialize E15. Federal and state requirements, fuel-industry procedures, retail-pump labeling and further testing all remain part of the broader rollout.

For truck fleets, the practical takeaway is straightforward: the E15 waivers apply to specified light-duty gasoline vehicles, not heavy-duty trucks or off-road equipment. Fleet managers and drivers must continue to follow the fuel specifications established for each vehicle and engine. The model-year approvals for passenger vehicles do not extend to delivery trucks, tractors, buses or other heavy-duty equipment.