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 17, 2007: work resumed. During venting of the house, mercury vapor was observed between 0.3 and 0.5 μg/m3 in the ambient air. Due to remaining “hot” spots, sheetrock from the front door along the Northern wall in the living room to the Western outside wall of the kitchen was removed to a approximate height of 3.5 ft from the floor. Once the sheetrock was removed, the areas along the bottom of the walls were vacuumed and decontaminated with HsCs-102. To allow access to “P” traps on the bathtub drains, the cabinets and an area of sheetrock was removed in both bathrooms. Personal item decontamination, screening and perimeter monitoring continued. Overnight security was maintained.
July 18, 2007: work resumed. During heating and venting of the house, mercury vapor was observed between 0.2 and 0.6 μg/m3 in ambient air. The tile inside of the front door was removed, as well as wood from the Northwest corner of the living room. Plumbing from the bathtub drains and the debris inside of the drains were removed, too. After removal, the drains were flushed with water; the work reduced the overall mercury vapor levels within the drains. Decontamination and screening of personal items continued. Overnight security was maintained, and the house was heated with the central heat and vented overnight.
July 19, 2007: work resumed. After the overnight heating and venting, the house was sealed up for approximately 40 minutes, and mercury vapor was observed 0.2 and 0.9 μg/m3. The entire house’s floors and baseboards areas were re-screened. Majority of the mercury contamination was observed from the front door in the living room along the Northern wall to the Western outside wall of the kitchen. Additional tile was removed, and these areas were re-decontaminated. In the areas of sheetrock removal, the bare wood was sealed with polyurethane and all the cracks were sealed with a latex caulk. The bathtub drains were retreated with Mercongel, and it will remain inside the drains until July 23, 2007. Decontamination and screening of personal items continued, as well asperimeter monitoring. Overnight security was maintained. Overnight the house was heated for 8 hrs, then vented for 2 hrs, and sealed for at least 1 hr prior to monitoring.
July 20, 2007: work resumed. Initial monitoring showed mercury vapor between 0.6 and 1.3 μg/m3. The floors in 1 of the 3 bedrooms, middle bedroom, and living room were sealed with epoxy floor paint. “P” trap within the garage was replaced. Continued perimeter monitoring. Personal items screening was completed. The house was allowed to vent over the weekend.
Continue the heating-venting of the house, monitor the indoor air and re-assess the situation for process modifications.
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.
|
