A natural gas pipeline in the Arkansas River between Little Rock and North Little Rock ruptured sometime Sunday or Monday, releasing about 3.9 million cubic feet of natural gas, a spokesman for Spectra Energy Corp., which owns the line, said Tuesday.
A 2-mile section of the river was closed to traffic Tuesday as the company tries to determine what caused the 24-inch pipeline to leak and tries to fix it, but a strong current is making it difficult to inspect, said Phil West, spokesman for the Houston-based company.
"We are looking into it. We don't know what caused it," West said. The leak "most likely occurred during the weekend. We're trying to figure that out."
Information given to the Arkansas Public Service Commission indicates that the leak occurred Monday and that the cause is unknown, said John Bethel, executive director of the agency's general staff.
He said the pipeline crosses the river near Bill and Hillary Clinton National Airport/Adams Field.
While the commission is aware of the leak, it does not have jurisdiction over Spectra Energy's pipeline because it is an interstate gas line, Bethel said.
The pipe that leaked is a backup line that runs parallel to Spectra Energy's main transmission pipeline.
The main line, which also crosses under the river, runs from Texas to New Jersey. In Arkansas, the line provides natural gas to CenterPoint Energy, West said.
Valves on a 4½-mile segment of the backup pipeline were closed before the leak occurred because it is not normally in operation, West said. The valves remain closed and there was no natural gas being released Tuesday.
West said the leak did not leave any residual natural gas in the river and that the released gas would have bubbled up and dissipated into the atmosphere.
"Just like any bubbles, natural gas would move up and out of the river quickly," West said.
A vessel belonging to Jeffrey Sand Co. sustained "a little bit of damage" related to the leak, said Clay McGeorge, president of the North Little Rock-based company.
He said no one with the company was injured and did not describe how the vessel was damaged.
Chief Petty Officer Bobby Nash, 8th District spokesman for the U.S. Coast Guard, confirmed that a stretch of the river was closed Tuesday.
"We closed down the waterway so they can work on the potential source of the leak," he said, adding that other parts of the river are shut down because of flooding.
Spectra Energy's dive team will use sonar and other tools to inspect the pipeline from the surface.
The company can also hire a team to repair the pipeline, but the Arkansas River is proving difficult, West said.
"The current has been an issue for the dive crew," he said.
City officials said they were not aware the pipeline had ruptured.
Little Rock Fire Chief Greg Summers said Tuesday that he hadn't been told about the leak.
"I'm not aware of it," Summers said. A check with the 911 dispatch office determined that it too had never gotten a call about the leak or dispatched any crews to the area.
Little Rock police spokesman Lt. Steve McClanahan also said he was unaware that a leak had occurred.
"For Sunday, we couldn't find anything in the system referring to a gas leak," McClanahan said.
Shane Carter, the spokesman for Bill and Hillary Clinton National Airport, said the airport hadn't been notified about the leak.
"No one has contacted us about it," Carter said. But he added that the airport might only have been notified if the leak had occurred adjacent to or on airport property.
The U.S. Environmental Protection Agency is aware of the leak, said Jennah Durant, spokesman for the agency's regional office.
The EPA is not responding to the leak because "natural gas is actually exempt" from the list of hazardous materials the agency is required to respond to, she said.
A spokesman for the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration did not return a phone call or email on Tuesday.
Since 2010, Spectra and its subsidiaries have reported at least 22 natural gas leaks to the federal Pipeline and Hazardous Materials Safety Administration. Those leaks accounted for the unintentional release of nearly 44.5 million cubic feet of natural gas from transmission pipelines or other equipment, according to data from the administration analyzed by the Arkansas Democrat-Gazette.
The companies released more than 293.5 million cubic feet of natural gas as a result of those leaks, a figure which includes intentional and other controlled gas releases during repairs.
According to the federal data, the gas leaks cost the company more than $10.1 million over the past five years, the majority of the costs coming from damage and repairs to company property.
"This spill is yet another example of the dangers posed to Arkansas by pipelines and dirty fuels," said Glen Hooks, chapter director for the Sierra Club of Arkansas. " Whether we are talking about oil spills in Mayflower or the gas spill ... the dangers to our health and natural resources from ruptured pipelines are enormous and unnecessary."
The leak from Spectra Energy's pipeline comes several days after an incident involving a different pipeline owned by CenterPoint Energy.
The flooding of the Arkansas River caused a 8-inch natural gas pipeline to leak Thursday, said spokesman Alicia Dixon.
She said the company discovered the pipeline, near the Interstate 430 bridge, was leaking at 3:30 a.m. It was shut down about three hours later.
"No customers were impacted and the bridge remained open," Dixon said. "Once the water recedes, we will assess the line and make the necessary repairs."
The line is part of the company's natural gas distribution system and serves customers in the Little Rock area.
Bethel, with the Public Service Commission, said the CenterPoint leak was not a safety hazard.
"We'll continue to explore what happened," Bethel said. "Based on the information we have presently it seems due to the high water of the river something struck the line and damaged it."
Since 2010, CenterPoint Energy companies have reported 18 leaks, ruptures or other equipment malfunctions that caused unintentional natural gas releases from distribution lines, according to federal data. In total, nearly 9.7 million cubic feet of natural gas were released in those instances, resulting in nearly $1.3 million in estimated damage and costs including about $884,000 in damage to public or private property not owned by the company.
Information for this article was contributed by Glen Chase and Chad Day of the Arkansas Democrat-Gazette.
A Section on 06/03/2015