On 2/15/08, a student at Emmett High School was doing an inventory of chemicals in the storage room of a chemistry lab when she reportedly noticed mercury beads on the floor. The spill was reported and the Caldwell Regional Response Team responded. Caldwell Regional Response Team reported that there were an unknown number of broken thermometers that were the likely source of the spilled mercury on the floor and counter. Visible mercury was cleaned up. Recovered mercury was secured, the building ventilated, and then returned to service. Caldwell RRT did not have access to mercury detection equipment.
When EPA was responding to a mercury spill at the St. Joseph's Catholic school in Boise on Saturday 2/23/08, it was discussed on a State Comm bridge call that there had been the spill at Emmett, and EPA was asked if they could conduct monitoring at the Emmett High School to confirm that the earlier cleanup was effective. EPA agreed and responded to Emmett High School the afternoon of 2/23/08 with EPA OSC and START contractor personnel. It was a Saturday, and the school was not occupied except for a the school principal and school district superintendant. Upon entering with a mercury vapor analyzer the unused laboratory room adjacent to the storage room where the spill had ocurred, EPA detected approximately 4,000 nanograms per cubic meter (ng/m3) of mercury in ambient air. Upon entering the storage room concentrations exceeding 10,000 ng/m3 were detected. Ambient levels in the hallway directly outside of the impacted rooms was approximately 600 ng/m3 (the ATSDR established recommended threshold for residential occupancy is 1,000 ng/m3). EPA shut and sealed the doors to the impacted rooms and recommended that the HVAC system not be turned on until the situation is abated. The OSC activated the ERRS cleanup contractor.
On Sunday, 2/24/08, EPA OSC, START and ERRS contractor personnel responded for cleanup at Emmett High School after finishing at the St. Joseph's school in Boise. EPA and START also screened shoes of personnel who had likely been in contact with the spilled mercury in the storage room, including the student who originally discovered the spill and three teachers who subsequently entered the room. Elevated levels of mercury were detected in the headspace of a bag containing the shoes of the student and one of the teachers. EPA screened the vehicles of these individuals and found no elevated mercury. The home of the student was also screened. Mercury cleanup was completed on 2/26/08. See Polrep 1 for additional details.
