On 27 June 2007, the Louisiana Department of Environmental Quality (LDEQ) contacted the EPA Region 6 hotline to report a mercury release at a home in Chalmette Louisiana. The EPA subsequently notified the National Response Center (NRC 840234) of the release. The release was originally reported to the LDEQ by the Children’s Hospital of New Orleans, La. The residents’ youngest child became ill a few weeks ago and was being treated at the Children’s Hospital. After several examinations, the residents brought to the doctor’s attention that they recently had found mercury within their home. The child was then tested for mercury poisoning, and tests indicated that the child had mercury levels approximately 40 - 70 times that of normal levels.
On 28 June, START-3 conducted an assessment of the residence. Initial air monitoring conducted by START-3 indicated levels of mercury in air of up to 60 micrograms per cubic meter (μg/m3). Based upon the START-3’s report, EPA senior management was briefed on the situation. On the morning of 29 June, ERRS was verbally tasked to conduct a site walk that same day utilizing the OSC’s warrant authority for emergency actions.
July 5, 2007: work resumed. After the heating and venting process, the house was shut-off for 1 hr; mercury vapor readings were observed to be between 39 to 53 μg/m3 in the living areas, and 24 μg/m3 and 5 μg/m3 in the attic and garage, respectively. The heating and venting process was repeated. During the venting cycle, the interior air was monitored and the mercury vapor readings were between 0.5 to 1.9 μg/m3. Prior to screening of resident's hard surface personal items, they were "clean" with HgCs-102. In addition, the perimeter of the staging area was monitored. At various times throughout the day, rain slowed the screening, segregation, and cleaning of personal items. Overnight, site security was maintained and the heating-venting process continued.
July 6, 2007: work resumed. After the heating cycle, the house was vented from 0230 hrs to 0800 hrs. At 0800 hrs, mercury vapor readings were found to be between 0.2 to 1.3 μg/m3 in the living areas. After the venting, another heating cycle was started and the decontamination of non-porous personal items continued. Perimeter monitoring of the staging area and segregation/screening of personal items also continued. At various times throughout the day, rain slowed the screening, segregation, and cleaning of the personal items. Prior to departure, another venting cycle was started. Overnight, site security was maintained and the heating-venting process continued.
July 7, 2007: work resumed. Before the next heating and venting cycle, the house floors and walls were re-clean. Perimeter monitoring and screening of personal items resumed. Personal items that remain contaminated after several “cleaning” attempts were documented and placed in roll-off box for offsite disposal. After 1 of the 3 bedrooms was re-cleaned, the room was sealed off in attempt to isolate non-contaminated areas of the house. Overnight, site security was maintained.
July 8, 2007: work resumed. The interior air in the bedroom that was sealed-off was monitored; mercury vapor was observed at about 0.5 μg/m3. In the remaining living areas of the house and with venting occurring, mercury vapor was observed to be between 0.2 to 0.6 μg/m3. Perimeter monitoring and screening of personal item screening resumed. Only the dinning and living rooms remain to complete the 2nd decontamination (re-clean) attempt of the house. Overnight site security was maintained.
Continue the heating-venting cycles, monitor the indoor air and re-assess the situation for process modifications. The drains, which have shown high levels of mercury vapors, will be treated with Hg decontamination agent. The screening, segregation, and deconning of the personal property will continue until completed.
Source of the mercury release has not been identified.
All members of the familiy except the daugther have elevated levels of mercury in their systems.
There is a heighten community concern most likely due to the mercury-contaminated residence being in the footprint of the Murphy Oil release. However, numerous analytical results of the materials from the Murphy Oil release indicated non-detects for mercury.
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