Refer to previous Polreps.
On March 06, 2005, in the early afternoon, EPA CID and DCDOH notified the EPA OSC of another reported release of Hg at Cardozo High School. OSC Brescia responded back to Cardozo to assist. CID collected another sample of the spill area identified by the OSC as Area 7, in front of room 13. Area 7 was never identified by MPD at any time as a spill area going back to the 02/22 and 02/23, 2005 intentional spill areas. In addition, Area 6 (third floor NW stairwell landing) was never reported to the OSC as a spill area either. Areas 1-5 were reported to the OSC as spill areas of concern and were subsequently cleaned/deconned. A thorough investigation of the entire facility was conducted to find additional Hg, after the successful cleaning of Areas 1-5.
On Monday morning 03/07/05 OSC Fitzsimmons responded. OSC convened a Unified Command meeting with representatives from the DCDOH and DCPS. DOH requested that in addition to decon of facility, EPA attempt to find any and all sources of Hg throughout the high school. These sources can include thermometers, wall thermostats, vials , beakers or other. DCPS official (Tom Brady) agreed. This request was never made before and clearly represented a change in direction from cleaning up the spill to investigation. It also would require much more assistance from DCPS and DCDOH. OSC Fitzsimmons requested that both entities provide a rep to the site so that a team approach would develop.
ERT and REAC arrived on 03/07/05. ERT was tasked with reviewing all data generated to date, to provide expertise and guidance for the OSC and to draft and implement the Site Investigation/Clearance Sampling Plan. This would provide for another fresh set of eyes to assist with this large volume sampling and investigation effort. REAC started rescanning areas identified by ERT as data anomalies (levels less than 1.0ug/m3 but greater than background). REAC thoroughly scanned these areas. No other areas of concern were found as a result. REAC than was tasked with performance of exhaustive search of facility classrooms, hallways and stairwells for mercury beads.
ERRS continued with decon efforts at Area 7. Decon SOPs within all areas where Hg beads were found include: 1) removal(hepavac) of all gross contamination (beads) 2) thorough search for additional hg beads in the area on hands and knees with putty knife to dislodge dirt and debris 3)scanning with Lumex to find additional microbeads that may be buried under tile, behind lockers etc. 4)Additional screening to ensure levels through out Area are well below 1.0 ug/m3, 5) hand wiping of area with Hg acidic soln to amalgamate any residual (this step is performed 5 or 6 separate times) 6) final mopping of entire area with same solution (once again 5 or 6 times)7) successive rescreening of entire area over a 2 hour period to allow for settling of dust. If screening numbers show levels well below the action level it is then left alone for final sampling.
REAC performed classroom/hallway/stairwell screening efforts on all floors starting with the third floor. In addition to overall data management, START initiated source investigation activities throughout the labs and chem storage areas and were successful in finding 3 wall thermostats, 24 thermometers and 6 containers of Hg in the labs. In addition numerous other haz mat hazards were identified. These included the finding of large quantities of old, poorly labelled and unlabelled, and improperly stored lab chemicals throughout six labs. Some of which were in close proximity to the students. Hg was also found in these areas within vials and other containers. Some haz mats included old picric acid, air reactives (sodium metal) and large quantities of cyanides. These hazards were brought to the attention of MPD, DCPS and DCDOH as well as the DCFD. On Thursday, 03/10/05 DCFD condemned all labs and disallowed access to these areas. It has to be emphasized that these areas (labs and chem storage areas) were never a part of EPA Hg cleanup activities and were found to be locked.
On Wednesday 03/09 after exhaustive decon of Area 7, the ERT Investigatory/Closure Sampling Plan was implemented. Sixty-eight, eight hour low volume samples were placed at locations throughout the facility as determined by the ERT. All samplers were placed on the floor as an aggressive approach to finding Hg. All windows and doors were shut. Heat in the building was elevated slightly to 75 - 80F to further allow for aggressive sampling. Samples were collected thru the night and delivered to the lab, afternoon of 03/10.
On 03/11/05 the air data (68 samples) revealed no elevated numbers. All numbers were well below the 1.0ug/m3 action level. This data was submitted to DCDOH for review and reoccupancy determination. Even after this data was returned, the OSC on 3/11, tasked both REAC and START to continue looking for Hg with the Lumex MVA to ensure that as many rooms as we could find (from the architectural design floor plans as well as roaming the facility) were scanned. Since no additional beads or even levels above background were found, REAC and ERT were demobed on 3/11 in the afternoon.
DCPS, due to chem lab problems determined that school should remain closed for another week. DCPS hired a cleanup contractor to remove lab packs on 3/12/05. The OSC monitored this removal activity to ensure proper health and safety procedures. The OSC also stressed to the contractor (TriCounty Enviro) that there was a potential to find Hg in Chem Storage Room 214A, since our cursory screening revealed elevated levels within it. On 3/12 the contractor revealed that it had discovered a bead of Hg on the floor of the chem storage area. As reported previously, this was an area which was not a part of this response by EPA but when asked by DCDOH and DCPS to expand our search for sources we obtained acess to it. This further cements the OSC's theory that a lot of the Hg findings are potentially historic spills never properly addressed before.
DCPS has requested that EPA certify all 750 plus student lockers free of Hg. The OSC has requested that DCPS and DCDOH lead this effort with EPA support. DCDOH and DCFD have, in the past, lead the personnel screening portion of this response and as such should therefore maintain this lead. EPA can assist with START personnel and instrumentation to assist but the actual opening and removal of items within the lockers should be conducted by District personnel. EPA Regional Counsel has reviewed this approach and concurs.
EPA will convene a panel of experts to review the data generated thus far to ensure accurate reoccupancy recommendation.
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