Ralphs Grocery Co. pleaded guilty in federal court to several charges stemming from the grocery retailer’s illegal hiring of hundreds of workers under fake names during a strike and lockout in the Southern California supermarket industry three years ago.

The chain pleaded guilty to five of 53 counts in an indictment returned by a federal grand jury last year, covering allegations of identity fraud, false representation of Social Security numbers, concealing facts relating to employee benefit plans, causing employees to falsely represent information to government agencies and conspiracy. Sentencing is set for Oct. 16.

Under the terms of the deal with, Ralphs would pay $20 million in fines and $50 million into a restitution fund for employees locked out during the labor dispute. Local unions also would be eligible to collect money from the fund granted they paid lockout benefits.

Ralphs, a unit of Cincinnati-based Kroger Co., initially pleaded not guilty to all the charges in January and a trial was set for next month.

In October of 2003, about 19,000 Ralphs workers were kept from their jobs at Southern California stores after Southern California grocery workers voted to strike against Safeway Inc.’s Vons and Pavilions chains.