Energy chief plays down bad effects of acid rain

''I don't want to stop acid rain, because 99.9 percent of all rain is of an acid nature,'' US Energy Secretary James Edwards said after addressing the American Power Conference. ''I think we need to do more research before we run off and worry about rain falling from the sky.'' Mr. Edwards said acid rain is ''good for crops'' in fields that are alkaline, because it helps ''neutralize the soil.''

Mr. Edwards, who seeks to liberalize the Clean Air Act, said the link between industrial pollution and acid rain is unclear. ''If you dig down in the glacial ice, it's more acid than the rain we have today, so I wonder what smokestacks from a couple of billion years ago were responsible,'' he said.

Acid rain is blamed for crop damage and the destruction of aquatic life in lakes in the Northeastern United States and Canada and for rapid disintegration of statues and facades in Chicago-area buildings.

Chemist Robert Ginsburg of the Chicago-based Citizens for a Better Environment said acid rain has a fertilizing effect in ''very specific situations,'' but in the vast majority of cases the effect on crops is detrimental.