U.S. EPA Administrator Christie Todd Whitman said yesterday that her agency would order General Electric to spend almost $500 million to dredge PCBs from the upper Hudson River. In doing so, Whitman disregarded a multi-million-dollar P.R. campaign by the giant company claiming that dredging would not improve the river’s health. Enviros, who had feared that closed-door meetings between the EPA and GE would result in a scaled-back cleanup plan, said the announcement was a big-time victory.