The Rancho Seco nuclear plant in California and the Pilgrim nuclear plant in Massachusetts are the worst-run commercial nuclear reactors in the country, said a consumer group's report released Monday.

The report by Public Citizen, a group formed by consumer advocate Ralph Nader, said other facilities scoring high on its "nuclear lemon" list include the Peach Bottom plant near Lancaster, Pa.; the Fermi 2 reactor in Laguana Beach, Mich., and the Oyster Creek plant in Forked River, N.J."Clearly, the risk of an accident in the United States is greatest at the worst nuclear power plants, and this report is designed to identify those reactors," said the study, which called for tighter government scrutiny of the listed plants.

The study, released on the two-year anniversary of the Chernobyl nuclear-plant accident in the Soviet Union, used government and industry data to rate the safety and economic record of the nation's 101 commercial nuclear plants.

Don Winston, a spokesman for the U.S. Council on Energy Awareness, a nuclear industry group, criticized the Public Citizen report as "superficial," saying many of its criteria had little real bearing on plant safety or efficiency.

For example, Winston said, many of the plant mishaps reported to the NRC were minor violations of regulations that did not reflect unsafe conditions any more than "running a red light proves a driver is dangerous."

All the "lemons" cited in the report ranked among the 15 worst plants in three or more areas of concern.

The study's overall 15 worst plants, in order, were: Rancho Seco; Pilgrim; Peach Bottom Units No. 2 and 3; Fermi 2; Oyster Creek; Sequoyah-1 near Chattanooga, Tenn.; Browns Ferry 1, 2 and 3, near Decatur, Ala.; Davis-Besse near Toledo, Ohio; Dresden 2 near Morris, Ill.; Lasalle 1 near Seneca, Ill.; Fort St. Vrain near Denver, and Sequoyah-2 near Chattanooga, Tenn.