Department of Justice Seal

TUESDAY, JUNE 16, 1998	
(202) 514-2008
TDD (202) 514-1888


           Company Charged With Illegal Emissions From Diesel Engines

	WASHINGTON  The Justice Department, on behalf of the
Environmental Protection Agency, yesterday sued Mack Trucks Inc.,
one of the leading U.S. manufacturers of heavy duty diesel
engines, for violating standards designed to limit emissions of
dangerous air pollutants under the Clean Air Act.

	"The American people deserve clean air to breath," said Lois
Schiffer, Assistant Attorney General in charge of the Environment
and Natural Resources Division. "Those who break the law will pay
a high price. This lawsuit is another example of the federal
government's determination to ensure full compliance with the
Clean Air Act."

	On Monday, the Department filed suit in U.S. District Court
in Washington, D.C. to respond to the company's termination of
settlement negotiations by filing its own lawsuit against the
federal government. 

	The suit alleges that Mack has been selling unlawful heavy
duty diesel engines equipped with devices that defeat the
engines' emissions control system, resulting in the emission of
illegal amounts of oxides of nitrogen (NOx).  

	NOx is an air pollutant that contributes to smog, acid rain,
and increased levels of lung disease. Heavy duty diesel engines
are used in tractor trailers and other large trucks.

	The suit asks the court to prohibit Mack from selling
engines with defeat devices, to order Mack to recall and fix
those engines currently on the road, and to require Mack to take
additional steps to offset the harm caused to public health and
the environment.  The suit also seeks civil penalties for the

	"Mack's use of defeat devices had and will continue to have
a significant adverse impact on the public, resulting in an
estimated 700,000 tons of excess harmful nitrogen oxide emissions
and more than $1 billion in extra health care costs over the life
of the engines," said Steve Herman, EPA Assistant Administrator
for Enforcement and Compliance Assurance. "By filing the lawsuit,
we are taking action to ensure that the company does not
compromise clean air and the public health now and in the

	"There simply is no excuse for circumventing federal laws
aimed at protecting and preserving our natural resources," said
Wilma A. Lewis, United States Attorney for the District of
Columbia.  "This lawsuit is the result of a collaborative effort
among the Environmental Protection Agency, the Environmental and
Natural Resources Division of the Department of Justice and the
U.S. Attorney's Office, and demonstrates our continuing
commitment toward enforcing the Clean Air Act." 	

	According to the charges, the company's engine software
controls the timing of fuel injection into the combustion
chamber, causing the engine to emit excessive amounts of NOx
while the truck is running on the open road.  However, the
company's engine software is designed in such a way so that these
emission levels do not show up on the federal test. Changing the
timing of fuel injection can increase fuel economy, but at the
expense of much higher emissions of NOx.

	The suit also alleges that these engines are not covered by
EPA's certificates of conformity, which all engines must have to
be lawfully sold in this country.

	Under the Clean Air Act, a manufacturer is prohibited from
selling or offering for sale any new motor vehicle or motor
vehicle engine equipped with any device designed to defeat the
engines' emission control system.  

	The government estimates that the affected engines, if not
fixed, could result in total increases in NOx emissions in excess
of 700,000 tons over the life of the engines.  

	Oxides of Nitrogen combine with volatile organic compounds
in the presence of sunlight to form ozone, one of six criteria
pollutants for which EPA has established National Ambient Air
Quality Standards.  An abundance of ozone near the earth's
surface is harmful to humans, agricultural crops and plants.  In
addition, oxides of nitrogen can cause acid rain, which is
harmful to fish, and high levels of nitrates in drinking water,
which is a human health hazard, especially for infants.

	Last week, the Department settled allegations that American
Honda Motor Co. Inc. and Ford Motor Company violated the Clean
Air Act by selling vehicles with disabled emission control
diagnostic systems and illegally installing defeat devices,

	Mack's failure to disclose to EPA the existence of these
defeat devices on its engines obstructed the EPA's ability to
protect public welfare and the environment before the engines
were sold.