General Motors Midsize & Luxury Car Group ELIMINATION OF MERCURY SWITCHES IN UNDERHOOD AND TRUNK LAMPS ______________________________________________________________________________ The (MLCG): Detroit/Hamtramck Assembly, Orion Assembly and Buick City Assembly located in Michigan, assemble the Cadillac Eldorado, Cadillac Deville, Cadillac Seville, Cadillac Concour, Buick Rivieria, Buick Le Sabre, Buick Park Avenue, Oldsmobile 88, Oldsmobile 98, Oldsmobile Aurora and Pontiac Bonneville. The three plants combined contain approximately 16.5 million square feet of floor space on 1,407 acres of land and employ approximately 21,750 people. Historically, mercury has been the material-of-choice for use in tilt switches for underhood and trunk lamp activation. It has been estimated that the mercury contained in underhood and trunk lamp switches accounts for 87% of mercury usage in automotive applications. This amounts to 12.2 million mercury switches containing a total of 8.5 metric tons of mercury per year. Clearly a reduction of mercury in this application would have a significant impact on automotive mercury usage. Through environmentally conscious design and manufacturing principles, the MLCG facilities will replace mercury switches with ball-type switches used in underhood lamp activation in their 1998 Cadillac and Buick models. Since the early 1990s, MLCG has eliminated all mercury switches in the trunk lamp activation and replaced these with trunk-ajar switches. Substance(s)Targeted: Mercury Targeted Elimination(s): 100% elimination from underhood and trunk lamps of MLCG vehicles Results and Advantages: The implementation of an alternative non-mercury switch for underhood lamps, a ball-type switch, will eliminate approximately 500,000 mercury switches in 1998 Cadillac and Buick models. These vehicles are the only MLCG models which contain the underhood lamps. The amount of mercury used in these underhood switches is approximately 1.5 grams; therefore, a decrease of 1,500 pounds of mercury a year will be eliminated from underhood mercury-containing switches alone. Objective: To eliminate the use of mercury in underhood and trunk lamp activation switches. This Internet document provided by the Michigan Department of Environmental Quality, 1-800-662-9278. Project Description: Materials engineers and release engineers from MLCG teamed with the supplier to develop the most effective ball-type switch for underhood lamp activation. Pilot studies began on February 21, 1997 for the Eldorado (K-Special), Deville, Park Avenue, Le Sabre and Riviera. A pilot study for the ball-type switches in S5S Sevilles is scheduled for May 16, 1997. Production for the 1998 model cars containing non-mercury switches will begin in mid May, 1997. Environmental Hierarchy: Pollution Prevention Pollution Prevention Approach: Material Substitution Environmental Media Addressed: Air, Water, Land Capital Investment: None Barriers Encountered: The use of ball-type switches are typically more expensive (approximately $0.09 a switch). Current indications suggest that by manufacturing lamp lenses from regrind material and the elimination of costs associated with removing mercury-containing switches from vehicles and switch disposal, the price differential can be recovered. Regrind use in the manufacture of the lamp lenses is scheduled to start production in mid May, 1997. This Internet document provided by the Michigan Department of Environmental Quality, 1-800-662-9278..