The Preliminary hearings for two former and one current Scranton School District officials charged with endangering children for failing to address lead and asbestos in district schools have been postponed until December.Dr. Alexis Kirijan, Jeff Brazil and Joseph Slack were scheduled to appear today for hearings that would determine if charges against them will be sent to county court.Kirijan, the former superintendent, Brazil, former chief operating officer, and Slack, daytime maintenance manager, were arrested and charged last month based on the findings of a statewide grand jury investigation.The State attorney general’s office says the three were repeatedly warned that water in multiple schools had abnormally high levels of lead and that other buildings had deteriorated walls containing asbestos, but failed to do anything about the danger.