The Clinton administration plans to launch an electronic system this fall that Americans can use to make a wide variety of payments to the government--from families paying for a national park camping license to corporations paying fines. The system, dubbed Pay.gov, "will be a one-stop shop for people to make government payments using the Internet," said the Treasury Department's deputy secretary, Stuart Eizenstat, announcing the initiative yesterday. The Pay.gov Internet site will be a secure, governmentwide electronic payment and collection system with the potential to handle any of the 80 million transactions the government now processes each year, Eizenstat said.