Today marked a day of solid progress on the conventional facilities front with the first concrete placement for the floor of the linear accelerator tunnel. A team of 24 workers placed the 1,400 cubic yards of concrete, starting around 3 a.m. and finishing around 8 p.m. One-hundred-forty truckloads of concrete were required to complete the task. It was the first of four large concrete placements required to complete the tunnel, which is 570 feet long and 70 feet wide.