SARNIA, Ontario (April 25)—Bayer Inc. will shut down operations at one of its two butyl rubber plants in Sarnia, along with the site's butadiene rubber operation, eliminating 300 jobs in the process. The company will consolidate butyl rubber production by this summer into Sarnia's Butyl II unit, which recently underwent a $100 million expansion that greatly increases the factory's capacity to produce halobutyl grades. The shutdown of the butadiene rubber unit, to be completed this fall, was directly related to the sharp drop in the North American market for BR, said Don Hummel, senior vice president of Bayer's Rubber Division. The company remains the top global producer of BR, he said, and will source customer needs from plants in Orange, Texas; Port Jerome, France; and Dormagen and Marl, Germany. After the cutbacks, Bayer will employ about 850 in Sarnia.