By the Environmental Protection Agency’s own estimate, the nation now spends 2.5 percent of its gross national product on pollution control. Regardless of whether, in absolute terms, that is too much money or too little, even environmental advocates concede that much of it is money not well spent, a consequence of overly rigid and wasteful laws. The Superfund hazardous waste law, for instance, generates billions of dollars in legal fees each year as companies fight to avoid paying for costly cleanups that sometimes have little or no effect on the environment. Recently regulators tried to use the Clean Water Act to force San Diego to spend $3 billion to upgrade a sewage treatment plant, even though scientists said that it would not make the Pacific Ocean environs significantly cleaner.