SAN RAMON, Calif. — Union janitors staged rallies at a Safeway here last week and at Lucky and Save Mart stores in this area to protest an ongoing contract dispute.

The workers are members of the Service Employees International Union Local 1877, which is the same group that staged a labor strike in May 2008 against some of the largest technology firms in the Silicon Valley and threatened to strike earlier this year against other employers, including state and local government buildings.

The recent protests are part of an ongoing dispute over a contract that expired Oct. 31. The janitors are not employed by the supermarket chains themselves, but by contract building-services companies, including Houston-based ABM Janitorial Services. Pleasanton, Calif.-based Safeway and Modesto, Calif.-based Save Mart, which also operates the Lucky banner in the region, are customers of the cleaning companies.

“In the current negotiations, ABM Janitorial Services has put forward a very strong proposal to include these workers in the same agreement that the other SEIU Local 1877 janitors overwhelmingly approved just last year,” a spokesman for ABM Janitorial Services told SN yesterday in a prepared statement. “That agreement provided workers substantially higher wages, improved access to family health care and other benefits through mid-2012. Under the proposal, the workers would now also qualify to receive wages, health care and other benefits consistent with those provided to the thousands of other local union-represented janitors.”

Local reports said the SEIU workers are being asked to accept a wage freeze, reduced benefits and a reduced starting wage. A spokeswoman for SEIU Local 1877 was not immediately available for comment.

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