The North Carolina Department of Environmental Quality (DEQ) has received the required Comprehensive Site Assessment (CSA), submitted by Colonial Pipeline on Jan. 20, which provides an estimated volume of 1.2 million gallons of gasoline released from the August 14, 2020, spill in Mecklenburg County’s Oehler Nature Preserve near Huntersville’s town limits.
Both the CSA and estimated volume released are under review by DEQ’s technical staff.
“The size and scope of this spill requires a rigorous approach to oversight and remediation,” said Division of Waste Management Director Michael Scott. “We will do a thorough review of the information provided, as it is vital to determine the full extent of the impact in order to guide the cleanup and protection of public health and the environment. DEQ will continue to hold Colonial accountable and oversee their cleanup efforts.”
In November, DEQ required Colonial Pipeline to recalculate the estimated release after determining that Colonial Pipeline had significantly underestimated the volume of gasoline released from the spill. The amount and continued rate of free product recovery, along with other data submitted by Colonial Pipeline, indicated that the spill is significantly larger than initially reported. As of Jan. 20, 582,169 gallons of free product and 253,082 gallons of petroleum contact water have been recovered and transported off-site for disposal.
The CSA identifies and describes the groundwater plume and soil impacts, and it is the next step in ongoing cleanup and remediation efforts. The CSA, and any additional information requested by DEQ, will dictate the direction of the Corrective Action Plan. DEQ must approve the CSA before Colonial Pipeline can prepare and submit its Corrective Action Plan, which details Colonial’s remedial actions.
Since the spill was reported, DEQ has required Colonial Pipeline to take all appropriate actions to protect the community and will continue to do so throughout the cleanup process. Efforts underway include the sampling of drinking water wells, installation of monitoring and recovery wells and recovery/removal of the free product (gasoline). Colonial Pipeline has installed pumps in the wells within the free product area and is actively recovering approximately 3,000 to 5,000 gallons of free product per day.
DEQ continues to closely monitor the progress of the site’s investigation and cleanup activities through onsite inspections. DEQ will pursue appropriate enforcement actions as needed based on the continuing investigation and remediation activities.
For more information, go to: https://deq.nc.gov/about/divisions/waste-management/underground-storage-tanks-section/colonial-pipeline-spill.