Environmental organizations and indigenous communities are already declaring victory, upon learning of a recent verdict by the Constitutional Chamber of the Supreme Court (Sala IV), which on Sept. 8 voted to overturn a concession allowing for oil exploration along Costa Rica's Caribbean coast.In effect, the verdict annuls the contract that, in April 1998, granted the Louisiana-based MKJ-Xplorations the right to explore four blocks - totaling 1.4 million acres - of land and sea near the Atlantic port city of Lim