North Carolina environmental officials say Colonial Pipeline significantly underestimated the amount of gasoline that spilled in Huntersville in August, and they've ordered the company to provide a new number.
The state Department of Environmental Quality says Colonial estimates that it lost 272,580 gallons of fuel in the spill. But as of this week, 267,313 gallons had been recovered, and Colonial's reports show that workers are still recovering 3,000 to 5,000 gallons of gasoline per day in the area.
"The amount and continued rate of free product recovery, along with other data submitted by Colonial Pipeline, indicate that the spill is significantly larger than initially reported. Colonial Pipeline has not provided a new estimated release volume," DEQ said in a press release Thursday.
DEQ has ordered Colonial to recalculate the total, which is to be verified by a third-party consultant. A DEQ spokeswoman said there's no deadline for the new number, "but this is a priority for the department."
Colonial Pipeline did not immediately respond to emailed requests for comment.
Two teenagers riding all-terrain vehicles in the area discovered the spill Aug. 14. It's in the Oehler Nature Preserve, off Huntersville-Concord Road east of downtown Huntersville.
Colonial initially said about 60,000 gallons of gasoline spilled. Then a month later, the company raised the estimate to 272,580 gallons.
The pipeline is actually two parallel pipes that carry petroleum products from Houston to New York City. One of the pipes is dedicated for gasoline; the adjacent is for other products, including gasoline, jet fuel and home heating oil.
After the spill, DEQ cited Colonial for violating state environmental rules. Tests of groundwater have shown gasoline-related chemicals at levels above accepted environmental standards.
DEQ previously has ordered Colonial to restore the surrounding groundwater quality to state standards. The company must also provide monthly reports on tests of soil, surface water, pipeline monitoring wells and drinking wells. The company also is required to submit a comprehensive report on the incident by Jan. 20, 2021.
Colonial Pipeline has estimated that the leak will cost it $10.3 million, with at least $2.5 million of that slated for environmental cleanup of the contaminated soil and groundwater.