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Enforcement

Mack Trucks Diesel Engine Settlement

On October 22, 1998, the Department of Justice and the Environmental Protection Agency announced an $83.4 million total penalty against diesel manufacturers, the largest civil penalty ever for violation of environmental law. Under this settlement, seven major manufacturers of diesel engines will spend more than one billion dollars to resolve claims that they installed computer devices in heavy duty diesel engines which resulted in illegal amounts of air pollution emissions. This settlement will prevent 75 million tons of harmful nitrogen oxide (NOx) emissions nationwide by the year 2025. The companies involved are Caterpillar, Inc., Cummins Engine Company, Detroit Diesel Corporation, Mack Trucks, Inc., Navistar International Transportation Corporation, Renault Vehicules Industriels, s.a., and Volvo Truck Corporation.

Alleged Violations: The seven companies sold 1.3 million heavy duty diesel engines containing illegal "defeat devices," which allow an engine to pass the EPA emissions test, but then turn off emission controls during highway driving. As a result, these engines emit up to three times the current level for NOx a harmful air pollutant.