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EPA (2), START-2 (6) and ERRS (3) arrived at the scene at approximately 1730 hours. The FBI HAZMAT Response Unit and the Kirkland Fire Chief briefed the EPA contingent about the condition of the scene and the actions taken during the course of the investigation. The FBI had removed most of the ricin extraction process materials as evidence, and collected and segregated the labeled and unlabeled hazardous materials in the backyard of the home. Additionally, the FBI had found approximately two ounces of spilled mercury in the upstairs living area. While the FBI completed evidence collection, EPA OSCs Rees and Terada obtained an access agreement from the owner of the property.
At approximately 1900 hours, the FBI transferred control of the site to the EPA for cleanup of the remaining hazardous materials. At this point, the EPA OSCs & the START-2 Team Leader did an initial walk-through of the apartment. While this reconnaissance was underway, the START-2 set-up and began hazard categorization of the segregated unlabeled materials in the backyard. The START-2 also prepared the Lumex 915+ Mercury Vapor Analyzer for initial characterization of the interior of the apartment.
The START-2 began field screening of the mercury vapor inside the apartment at approximately 1930 hours. The initial mercury vapor concentrations in the carpet were 4.0 ug/m3, the upstairs atmospheric concentrations averaged 15.3 ug/m3, and the mercury vapor concentration immediately around the spill area next to the bedding in the main living area was 39.1 ug/m3. These readings were compared to the EPA residential relocation threshold of 10 ug/m3, the ATSDR recommended clean-up goal of 1 ug/m3, and the EPA clean-up goal of 0.3 ug/m3.
ERRS and START-2 personnel began removing all the contaminated carpeting, padding, and bedding from the apartment at approximately 1945 hours. ERRS and START-2 personnel collected the spilled mercury in a four ounce sample jar using pipettes and duct tape before attempting to remove the soiled carpet. Contaminated material was placed into plastic bags for removal from the apartment and then placed into one of three 1 cubic yard solid waste bins for later disposal. The apartment was cleared of mercury contaminated floor coverings and furnishings by 2100 hours. The windows in the apartment were opened and the rooms were allowed to ventilate for approximately 30 minutes. After ventilation, the apartment windows and doors were sealed and the interior atmosphere was allowed to equilibrate for about 30 minutes. Upon equilibration, the START-2 entered the apartment with the Lumex and conducted confirmatory field screening, which revealed residual mercury vapor concentrations of 0.25 ug/m3.
During this clean-up inside, the START-2 completed categorizing the hazards of the unknown materials, which turned out to be mostly corrosive solutions of sodium hydroxide. Following identification, ERRS packaged all of the hazardous materials for proper disposal. The START-2 also collected five samples from the kitchen, where the suspect was preparing his ricin, and tested them for ricin using the Alexeter BTA. All tests were negative for the presence of the toxin. The START-2 collected one soil sample for VOC and Metals analysis in an area where the suspect was seen dumping waste materials in the backyard of the property. The START-2 also collected one sample from one of the remaining culture dishes in the kitchen for confirmatory analysis for ricin. ERRS collected a profile sample from the solid waste containers for total mercury analysis.
Prior to clearing the site, the START-2 conducted field screening for mercury in the main residence at the property to ensure that there was no cross-contamination. The mercury vapor concentration for all areas inside the home was below 0.03 ug/m3, or one order of magnitude below the EPA clean-up goal. The EPA, START-2, and ERRS demobilized from the site at 2300 hours.
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