A crash training like no other that has been held in Manteca, the staged rollover of a large school bus into a flood retention basin will take place today and Thursday afternoons near the corner of Airport Way and Louise Avenue.The City of Manteca Fire Department’s training division is offering the 2011 Mass Casualty Incident Training Simulation to staffers of the school district as well as to the EMTs and paramedics of the Manteca District Ambulance Service.Half a dozen “injured bus riders” are to be rescued in the hour-long scenario that is scheduled to last from 5 until 6 p.m. School district bus operator instructor Melinda Trimboli said the riders will be sitting out the hot bus mostly as volunteers. Some will be using the event to fill their required training hours.One “victim” will have a broken leg and be a challenge in the removal from the bus that is tilted on a 45-degree angle.Fire Captain David Marques lauded Dennis King of Manteca Towing Service for offering to set up the crash site and for putting the bus into the crash configuration. Marques and firefighter Franco Torrice put the volunteer “injured” victims through a brief orientation Tuesday morning at the retention basin at the corner of the bus garages and storage lots at the school district office campus.The “victims” were all given the opportunity to crawl through the emergency exit at the rear of the bus and try to get used to the tipped condition of the vehicle’s interior.