At least 500 gallons of gasoline have spilled from an underground 12-inch pipeline in a marshy area of Moccasin Bend about 1,000 feet from the Tennessee River.
Complaints of a gasoline smell near the Colonial Pipeline Co.'s Moccasin Bend delivery facility on Wednesday afternoon led firefighters to a spill site around an underground pipeline in the industrial area off of Pineville Road, according to fire spokesman Bruce Garner.
Colonial spokesman Sam Whitehead said that line and a second nearby distillate pipeline were shut down immediately for safety reasons.
Whitehead said the spill tally could go up.
Colonial reported a preliminary spill estimate to the National Response Center of 500 gallons, "but that number should be revised as the investigation continues."
"None [of the spill] has reached the river that we are aware of," he said. But some cleanup is necessary and will be ongoing in the wetlands area. We've been notifying state and local agencies ... and we will be subject to all the rules and regulations concerning the environmental regulations."
He said the gasoline pipeline in the area has been excavated and will be repaired or replaced.
He said the company is investigating the cause of the spill, and he added that an internal inspection tool in 2011 had found no anomaly in the pipe.
He said he did not know the age of that section of pipeline -- which carries gasoline to Nashville.
Tennessee Department of Environment and Conservation spokeswoman Meg Lockhart said state regulators will provide guidance to Colonial and its environmental contractors.
Garner said environmental cleanup companies already have placed absorbent booms and other barriers around the spill site in an effort to soak up the fuel and keep it away from the Tennessee River.
Colonial Pipeline was the company that lost at least 75,000 gallons of spilled diesel fuel in a deep sinkhole of Lookout Mountain in 1996.
That spill was discovered in early February in the wake of an thunderstorm that became an ice storm. The cause was later determined to be an electrical arc from nearby power lines that fell from the weight of ice. The arc melted a hole in the pipeline. The spill went unnoticed for about three days, despite gauges that should have alerted pipeline operators of pressure changes.
That was but one of several Colonial spills that caught the attention of federal investigators in the late 1990s.
A Chattanooga Times analysis of federal pipeline spill records revealed that Colonial accidents accounted for more than 25 percent of all the pipeline spills in the nation during the first eight months of 1996.
And in the five years previous, the company had 64 other accidents, totaling more than $22.5 million in damage and 1,851 injuries, according to federal figures.
More than a fourth of those spills occurred in Tennessee, Alabama and Georgia.
In April, 2003, Colonial was ordered to pay a record $34 million fine to the U.S. Environmental Protection Agency for spilling 1.45 million gallons of fuel and oil nationwide from 1996 to 2000, including the spill on Lookout Mountain.
In the Lookout Mountain spill, only 2,000 gallons of the oil was recovered.
Colonial and environmental officials said they believed the bulk of 70,000 gallons of diesel fuel -- enough to fill more than eight large tanker trucks -- sank into a 105-foot sinkhole in the mountain and became bound there in the soil and the maze of caverns inside the mountain.
Cleanup sponges floated for weeks on Chattanooga Creek and the banks of the Tennessee River, waiting for an oil sheen to appear.
None did, but several caves on the property of the U.S. Park Service had to be closed because of oil fumes.
On Thursday evening, Whitehead recalled the Lookout Mountain spill.
"We're a different company now. Since 1996, we've had a record we can be proud of," he said.
Colonial's 50-year-old pipeline system carries 100 million gallons of oil and gasoline products daily from the Gulf Coast throughout the Southeast and Northeast. Whitehead said 50 million consumers use the products.
"There are three really important things we will focus on [concerning the Moccasin Bend spill]: keeping the public safe, returning things to normal, and keeping everyone informed," Whitehead said.