In June of 2007, the South Carolina Department of Health and Environment Control (SCDHEC) requested that the EPA Emergency Response and Removal Branch (ERRB) perform a removal site evaluation (RSE) at Wescott Plantation. Explosive levels of methane had been noted at two homes in Wescott Plantation in previous independent reports.
After conducting a briefing on Tuesday, June 26th, 2007 with the State, the EPA On-Scene Coordinator (OSC) determined that it was necessary to conduct air monitoring for methane in citizen-requested homes. The State estimated that between 20 and 30 homes would request the service. Notifications were made to State, City and County government entities that included the North Charleston Fire Department and Police Department, North Charleston City Management, Dorchester County, additional levels of SCDHEC including public affairs and program management, EPA ERRB management and included a consult with the Agency for Toxic Substances Disease Registry (ATSDR).
At 10:00 am on Wednesday, June 27, 2007, the OSC conducted a unified command meeting with members of the above notified parties at the nearest fire station to Wescott Plantation homes. In addition, several representatives of the homebuilder (Lennar) were in attendance.
Public relations were coordinated through Sherryl Carbonaro, EPA CIC and included representatives from SCDHEC and the City of North Charleston.
Monitoring operations were conducted by OSCs Randy Nattis and Alyssa Hughes and included contractor support.
The City of North Charleston provided a mobile command post (MCP), manned by the North Charleston Fire Department and represented the city thru Fire Chief Leonard Judge Jr.
SCDHEC provided additional support thru program management attendance, emergency responder presence, and community involvement personnel. SCDHEC personnel were used in contacting residents, briefing the OSC on historical areas of concern, and providing oversite after EPA's departure.
Lennar offered and provided resources including access to previous documentation and contractor representatives concerning methane monitoring and remediation. In addition, they offered to provide the OSC with requested historical aerial pictures and plot development overlay.
Air monitoring was conducted in 19 homes over a two day period. All homes were significantly below the lower explosive limit (LEL) for methane, including the two original homes of concern. All homeowners were notified of their individual results via letter report on Friday the 29th and approximately 75 additional homes received updated assessment information fact sheets. A spreadsheet is located in the documents section of this website that lists the air monitoring results for each of the homes. The fact sheets are also included.
Additional requests for air monitoring for methane will be conducted by Lennar with as required oversite from the SCDHEC district emergency responder, Terry Yarborough.
In recent months, subsurface venting systems were installed at the two homes in which elevated levels of methane were found. Based on the ERRB monitoring data, both these systems appeared to have significantly reduced the once higher levels of methane.
Concerns were expressed by homeowners over the possibility of additional gases being emitted into their homes from the subsurface. After a consult with monitoring operations, the decision was made to air sample the existing subsurface soil venting system in the two homes that had previously displayed higher levels of methane. The results will be available in two to three weeks and will be analyzed for volatile organic compounds.
The final RSE will be available in 60 to 90 days and will include both the on-site work and requested background material. Historical reference documents have been of particular public interest in both the media and local community. In the interest of expedient public dissemination, Lennar has agreed to make these documents available by late next week in an electronic format. Those reports will be added to this website upon receipt.
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