By Lisa Hofmann The air will a be a little cleaner thanks to an agreement among the EPA and major oil refiners BP Amoco and Koch Petroleum Group. BP Amoco is slated to spend more than $500 million on improvements at nine of its refineries to reduce all emission sources. Koch will invest about $80 million at three refineries to achieve the same goals. In addition to improving leak detection and work practices, the agreement provides measures for increasing the safety of workers and local communities that may be affected by accidental pollutants. BP Amoco's Mandan, N.D., refinery already completed installation of a new distillate desulfurization unit that produces low-sulfur diesel fuel that meets federal requirements. EPA Administrator Carol Browner says that the pollution controls will significantly decrease pollution in the next eight years, eliminating about 56,000 tons each year from the BP Amoco and Koch facilities. "This agreement signals our intent . . . to improve our environmental performance in manufacturing," says Doug Ford, BP Amoco's refining and marketing CEO. Earlier in the year, BP Amoco and Koch initiated talks with the EPA to avoid EPA enforcement action and extensive litigation. Also agreeing to pay penalties for past violations, BP Amoco shelled out $10 million, and Koch $4.5 million. The EPA viewed their cooperation and commitment to the environment as deserving of a "clean slate" for certain past violations. Accounting for 15% of the total U.S. refining capacity, the Koch and BP Amoco agreements address pollutants that induce serious respiratory problems and that include nitrogen oxide and sulfur dioxide. Sulfur emissions are the cause of acid rain, and nitrogen oxide leads to smog. The agreement will cut nitrogen oxide and sulfur dioxide emissions by almost 50,000 tons annually.