Published: Oct 08, 2012 7:12 PM EDT
Updated: Oct 09, 2012 6:31 AM EDT

SAN JUAN CAPISTRANO, Calif. (AP) - Federal regulators say the proposed restart of the troubled San Onofre nuclear power plant in California could require a detailed review that might last months or even years.

Nuclear Regulatory Commission Regional Administrator Elmo Collins told reporters Monday it's not yet clear if the restart plan Southern California Edison submitted last week will require an amendment to the plant's operating license.

Such reviews can involve a thicket of hearings, appeals and other steps that can take as long as two years to complete.

Collins says Edison contends such a review isn't needed. But he says the NRC considers it an "open question."

Edison plans to repair one of two damaged reactors, Unit 2, and run it at reduced power to reduce vibration that has damaged tubing that carries radioactive water.