On October 5, 2004, at the request of EPA ERRB telephone duty (NRC Report Number 737045), OSC Carter Williamson responded to an alleged mercury spill at a residential property in Waynesville, North Carolina. According to the report, a housekeeper for a family located at Timucua Trail had accidentally knocked over a bottle of metallic mercury while cleaning a guest bedroom. This incident had apparently occurred on or about July 1, 2004, two months prior to being reported to the NRC. The bottle of mercury had been stored on a book shelf by the homeowner and while the housekeeper dusted the furniture, the shelf holding the bottle of mercury shifted and the mercury spilled onto the carpeted area immediately in front of the housekeeper. The housekeeper tried to vacuum up the material as did the homeowner. Some time later, the housekeeper became ill and decided to report the incident to the NRC.
On October 5, 2004, after receiving a directive to proceed to the location of the incident, OSC Williamson ordered START (Tetra Tech EM Inc.,) and ERRS contractor Ferguson Harbor Inc., to participate in the assessment and possible clean-up of the primary location of the spill and any other residences affected. Activities conducted during this emergency action included the initial baseline monitoring of mercury levels using a Lumex Mercury Vapor Monitor RA915 (Lumex) in the housekeepers home, the housekeepers friends home and finally at the location of the spill, 60 Timucua Trail. On the afternoon of October 5, 2004, START performed air monitoring surveys inside and around the residence of the housekeeper at 171 Conner Ridge Road, Waynesville, North Carolina. Average mercury vapor readings inside the residence were in the range of 3 nanograms per cubic meter (ng/m3). START also analyzed bagged clothing worn by the housekeeper when the incident occurred in July. These readings were 1,441 ng/m3.
Also, on the afternoon of October 5, 2004, START performed additional air monitoring on the housekeepers friends home. Average readings were in the range of 4 ng/m3. On October 6, 2004, after a telephone conversation between the homeowner of the home at 60 Timucua Trail and OSC Williamson, access was granted to perform air monitoring inside the home where the mercury was allegedly released. Average mercury readings inside the residence were in the range of 15,700 to 43, 725 ng/m3. As the average readings in the residence exceeded 10,000 ng/m3, OSC Williamson instructed the residents that they should relocate to another location during the remediation of their home.
The subsequent removal of mercury (free product), contaminated carpeting and miscellaneous items was accomplished by ERRS using proper PPE (Level C), specialized mercury vacuums, blowers and HGX Mercury Decontamination Powder solution. The home was heated, vented and monitored until the sustained readings dropped below 1,000 ng/m3. Items and personal belongings with sustained readings of 10,000 ng/m3 and below were returned to the homeowner. Items that sustained readings above this threshold were photographed, documented in the START log book and packaged for later disposal at a subtitle D landfill. The air sampling results indicated that remediation activities at the 60 Timucua Trail residence were successful in reducing mercury concentrations below the recommended atmospheric exposure limits for mercury in residential properties. On October 11, 2004, OSC Williamson authorized the residents of 60 Timucua Trail to reoccupy their residence. No removal actions were conducted at 171 Conner Ridge Road and 89 Claude Brown Drive, the homes of the housekeeper and her friend, respectively.
All recovered Mercury and contaminated carpet and miscellaneous items were either placed into over-pack drums and/or a roll-off container based on their respective readings and disposed of through a approved hazardous waste designated facility. The material was profiled and properly disposed of at an CERCLA compliant and approved Hazardous Waste Landfill. The Hazardous Waste was shipped as waste code D009.
