Thousands of Richmond residents filed suit against Safeway, charging that 18 deaths and a variety of health problems were caused by a fire that gutted its 480,000-square-foot distribution center last year. The fire burned for five days in July, creating a lingering stench and raining ashes on a surrounding low-income residential area. The suit, filed in Alameda County Superior Court, lists 5,500 plaintiffs in the first 44 pages. Safeway, which has settled thousands of claims out of court since the fire, had no comment. Residents affected by the fire allege that the grocery chain offered them only nominal payments because they are poor and black.