We've been talking a lot lately about alternative energy sources and how to come up with an effective energy policy. Nuclear power is being spoken of as a centerpiece of the new energy plan. Any discussion of nuclear power in the US eventually comes back to Three Mile Island, site of America's worst nuclear incident, back in 1979. Along these lines, it seems prudent to note that AmerGen Energy Co., the company that runs Three Mile Island has applied for a 20-year extension to its operating license. It also seems fair to point out TMI has been running since 1979 without any major problems, although the Three Mile Island Alert group contends that the company has failed to clean up radioactive waste.