Colonial Pipeline Co. said the fire in a rural area southwest of Birmingham, Alabama, was "significantly smaller" since Monday, and an environmentalist said the blaze had shrunk considerably from when it was shooting flames hundreds of feet in the air like a geyser of fire.
"It was about the size of a person last night when I saw it," said David Butler of Cahaba Riverkeeper, who has worked closely with the company to help prevent environmental damage.
The company — which is letting the fire burn itself out — has said it hoped to restart the line as early as this weekend. But it can't fully assess the damage and begin repairs until the blaze is out, and it's unclear when that might happen.
Based in suburban Atlanta, Colonial Pipeline has said as much as 168,000 gallons of gasoline could have burned, spilled, evaporated or remained in the pipeline following the blast Monday afternoon. The pipeline supplies gasoline to the Southeast, and officials are worried about fuel shortages and possible price spikes.
North Carolina Republicans urged their supporters to vote early and avoid any gas-related disruptions on Election Day, but Georgia Gov. Nathan Deal urged people to stick with normal fuel usage rather than stocking up and causing a spike in demand.
Meanwhile, U.S. House Democrats asked for an investigation of Colonial Pipeline. Five ranking members of panels dealing with energy, transportation, infrastructure, pipelines and investigations released a letter to Transportation Secretary Anthony Fox seeking the review.
The House members cited the deadly explosion earlier this week and a large spill in September just a few miles away. The company said the pipeline exploded as a nine-person crew was attempting to make a temporary repair that would allow for a permanent repair to the area where the spill occurred.
The letter also mentioned smaller spills in 2015 in North Carolina and Virginia, where several thousand gallons of petroleum product spilled.
A statement by Colonial said it takes accidents seriously and already is cooperating with investigators.
"We have robust system integrity, inspection and maintenance programs that meet or exceed all federal regulatory requirements," the statement said.
The damaged pipeline, which runs from the Gulf Coast to New York City, provides almost 40 percent of the region's gasoline and usually operates at or near full capacity. Combined with a nearby pipeline for diesel and aviation fuel, the two lines carry more than 2 million barrels of fuel daily.
Colonial said it only took a few hours after the explosion to restart the pipeline carrying diesel and jet fuel.
Since 2006, Colonial Pipeline has reported 178 spills and other incidents that released a combined 193,000 gallons of hazardous liquids and caused $39 million in property damage. Most were caused by problems with materials, welding or some other equipment failure, according to federal accident records reviewed by The Associated Press.
The company paid $381,000 in penalties for violating safety rules during the same period.
AP reporter Kathleen Foody in Atlanta contributed to this report.
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