On April 22, 1970, millions of concerned Americans gathered in communities and on campuses across the country to celebrate the first Earth Day - and launch the environmental movement. Oil spills, pesticide poisonings and other disasters had generated intense concern about the health of planet Earth. Now, as the 25th anniversary of Earth Day approaches, signs of progress in the U.S. abound: Dirty rivers are again clean; air pollution has been greatly reduced; and the eagle and other endangered species have been drawn back from the brink of extinction. But environmentalists say that tough new steps are needed to finish the job. Meanwhile, Republican lawmakers say environmental regulations are forcing businesses and individuals to pay too high a price for environmental protection.