The Bush administration asked a federal judge yesterday to dismiss a challenge by General Electric to the Superfund toxic waste cleanup law. Companies faced with multi-million dollar cleanup costs have repeatedly attacked the 1980 law, arguing that it leads to more legal tangles than environmental improvements. In the most recent sally, GE filed suit in November 2000, just before the U.S. EPA announced that the company would have to foot an estimated $500 million bill for dredging PCB-contaminated parts of the Hudson River. GE, which dumped some 1.3 billion pounds of PCBs into the Hudson between 1946 and 1977, is arguing that the Superfund law violates due process by granting federal regulators unlimited authority to order expansive — and expensive — cleanups with no chance for timely judicial review. Justice Department attorney Wendy Blake argued that GE does not have standing for a broad-based attack on the law and called the suit “a fishing expedition.”