The story goes back to 1967, when Texaco, a U.S. oil company that now is part of Chevron, discovered oil in northeastern Ecuador. Between 1971 and 1992 Texaco, in partnership with state-owned PetroEcuador, extracted more than 1.5 billion barrels of oil from this area...Texaco disposed of wastes from its work in a manner that plaintiffs in a class-action lawsuit -- called Aguinda vs. Texaco -- contend is responsible for the area's high rate of cancer, an assertion the oil company disputes.