LOS ANGELES -

The operator of California's troubled San Onofre nuclear power plant is proposing to restart one of the plant's twin reactors.

Southern California Edison says in a statement Thursday it's filed the proposal with the Nuclear Regulatory Commission, which is expected to take months to review.

The plant is a major source of power in Southern California and is located 50 miles southwest of the Coachella valley.  It has been shut down since Jan. 31, after a break in a tube carrying radioactive water. Investigators later found excessive wear on hundreds of tubes inside the plant's steam generators.

The company also submitted documents outlining repairs and safety measures proposed for restart and safe operations at the plant.

The announcement is certain to cause fierce blowback from environmental groups and activists that have argued the plant is too damaged to be restarted safely.