Contract talks resumed in San Francisco in a 6-week-old strike by cemetery workers. Health insurance costs are the main issue, management and union spokesmen said. The strike against 19 San Francisco Bay Area cemeteries began March 18 after a stalemate in negotiations. Funeral homes have estimated that bodies are accumulating at the rate of 10 to 20 a day. Owners are requesting that workers pick up increases in health insurance premiums beyond a certain level. “That’s the major stumbling block,” said Joan Twomey of Cemetery Workers and Greens Attendants Union Local 265. Because of concern about the issue, the 180-member union will not respond to a management request to return to work for two weeks and submit the matter for binding arbitration if a new contract cannot be agreed upon, Twomey said. A four-month strike in 1971 left 1,800 bodies unburied and stored in sealed caskets.