Finished in 2009 at a cost of almost $7 billion, the REX natural gas pipeline - running from the gas fields of Colorado through Ohio to the edge of Pennsylvania - stands as one of the nation's most ambitious infrastructure projects in a quarter-century.
It was also a job plagued with problems, demonstrating that despite industry assurances that new lines are safer than ever, they may not be safe enough.
In 2009, just six weeks after passing a battery of final pressure tests, the line leaked natural gas - triggering an evacuation of nearby homes in southeastern Ohio. The leak occurred in a pipeline section that federal safety inspectors had previously flagged for poor construction techniques.
In a recent interview with The Inquirer, Cynthia L. Quarterman, the nation's top pipeline regulator, described the REX pipeline as "massive in size - and riddled with issues."
Quarterman said her agency, the Pipeline and Hazardous Materials Safety Administration, or PHMSA, is taking seriously the REX pattern of incidents and has an ongoing investigation into them.
She said she made REX her first field visit after taking over PHMSA two years ago.
"I wanted to go personally to send a message to the owners and operators of REX, that they needed to get their act together," Quarterman said.
Even so, the main owner of the pipeline - industry giant Kinder Morgan - has not been fined.
The leak in Ohio was the last in a string of problems with REX. One worker digging the line in Wyoming was incinerated when his bulldozer hit another buried line; another firm was fined for not marking it properly. In Kansas, independent inspectors said they received threats when they flagged bad work.
"It went off the rails in so many ways," one inspector said in an interview.
In a recent statement, Kinder Morgan did not address the problems in the REX line, but said it had one of the industry's best safety records.
"We are committed to operating our assets safely to protect the public, our employees, contractors and the environment," the statement said.
Short for Rockies Express, the REX line is big - 42 inches in diameter - and carries gas compressed up to 1,440 pounds per square inch. Every day, it carries 1.8 billion cubic feet of natural gas. That's enough to serve 18,000 American homes for a year.
At one point, Kinder Morgan explored extending the line from Ohio, through Pennsylvania, to Princeton, but that plan has been shelved.
As a frenzy of gas pipeline construction envelops Pennsylvania, the litany of problems that plagued the REX line tells a cautionary tale.
The line's main owner, Kinder Morgan, was founded in 1997 by Richard D. Kinder, a former president of Enron. This year, Kinder made Forbes magazine's list of the 50 wealthiest people in the United States, with a net worth of $6.4 billion.
In October, Kinder's company agreed to pay $21 billion to buy El Paso Corp. Once the deal closes next year, Kinder Morgan will become the biggest pipeline firm in the country, overseeing more than 67,000 miles of pipe.
After a spate of accidents earlier in the last decade, some critics wondered whether its pace of acquisitions was simply too fast.
In 2004, five workers were killed when a backhoe hit a Kinder Morgan gasoline line in Walnut Creek, near San Francisco.
A Kinder Morgan subsidiary was later convicted of six labor-code felonies and agreed to pay $15 million. Investigators said the company failed to mark the line properly before crews began digging.
PHMSA said later that the accident was part of a long list of problems on Kinder Morgan's West Coast pipelines. It blamed the firm for a "repeated failure" to use internal inspection tools to identify problems.
In one case, PHMSA officials said, the firm hadn't fixed a stretch of corrosion 14 feet long. The pipe ruptured in 2004, spilling 60,000 gallons of fuel into a wildlife marsh in San Francisco Bay. In the end, Kinder Morgan agreed to spend $90 million to improve the Pacific Operations system.
Most recently, federal regulators in May proposed to fine Kinder Morgan $425,000 for a 2009 accident in which 8,600 gallons of fuel oil spilled in Perth Amboy, N.J.
The regulators said the terminal there had no warning procedures to alert workers when a key valve was closed in error. In reply, Kinder Morgan said that the proposed fine was excessive and that it had improved its procedures.
As for the 1,679-mile REX line, at a PHMSA conference in 2009, a Kinder Morgan executive said the sheer scope of the project had made it hard to manage a series of personnel and quality-control shortcomings.
"We had issues all the way across," Dwyane Burton, vice president for operations and engineering, said in a videotaped presentation.
"We were just juggling a lot of balls at one time. ... It's just a tremendous amount of project workload going on."
The fatal accident on REX happened Nov. 11, 2006, when Bobby Ray Owens, digging the trench for the project, struck a buried pipe owned by El Paso Corp. The explosion generated a fireball and temperatures as high as 3,000 degrees. Owens, 52, was found dead next to his bulldozer, his arms raised in a defensive gesture.
El Paso later paid a fine of $2.3 million for several violations, the largest ever levied by PHMSA. The agency faulted El Paso for providing an inaccurate map.
In early 2007, the Federal Energy Regulatory Commission, another regulator, grew so exasperated with construction problems that it threatened to shut the REX project down.
REX promised to do better. Scott Parker, president of Natural Gas Pipelines for Kinder Morgan, said there was so much pipeline construction that the company had trouble finding experienced workers.
The previous winter, Parker said, the company had driven its crews to keep working in brutal winter weather, "with over four feet of snow cover in some locations, high winds, drifting snow and ground blizzards." In hindsight, he wrote, this "effort to meet in-service deadlines" may have been a mistake.
Later in 2007, in Kansas, three private safety inspectors attached to the project quit in protest, saying that a REX subcontractor had pressured them to keep quiet about substandard work, making threats and offering bribes.
One of those inspectors, Don Stewart, later told the Dayton Daily News he had resigned because of the subcontractor's "careless, wanton, reckless unconcern for human safety."
In an interview with The Inquirer, another inspector said the project was marked by "a lot of people doing things to speed it through, and things going wrong."
"That was real unusual," he said, asking that his name not be published. "I never worked with one like that, and I never want to again."
The subcontractor, Latex Construction Co., a Georgia firm, did not return several calls seeking comment.
On Nov. 14, 2009, two days after the final leg of the line went into full service, REX ruptured south of Zanesville, Ohio, spewing 127,000 cubic feet of gas. There was no explosion and no one was hurt, but the release forced 50 people to evacuate.
Bob Sharp, an activist on pipeline issues in Ohio, said a friend who lived near the site called him shortly after the pipe ruptured, yelling: "We got gas blowing! We got rocks filling the air!"
"Had it caught fire, there would have been a lot of hurt people," Sharp said. "They just got lucky."
Had the gas ignited, an explosion on REX would have a blast radius of about 1,000 feet.
After the leak, PHMSA disclosed something startling: The line had failed in the very 31-mile segment that a federal welding inspector had flagged for unsound work five months before.
The inspector, Gery Bauman, said he had warned Kinder Morgan supervisors about "inappropriate" construction practices and welders "who were not following the company's procedures," according to PHMSA documents.
"Mr. Bauman stated that he received assurances from Kinder Morgan's senior project engineer that appropriate remedial actions would be taken," the agency stated.
Even so, the line failed. And it ruptured even after passing a key exam - the "hydrostatic test," in which the line is filled with water and checked for leaks. Typically, this is among the last in a battery of tests used to guarantee the safety of a pipeline.
PHMSA concluded that the rupture - six feet long - was due to bad welding. The agency said an examination showed that it reflected the same bad welding practices spotted earlier.
The agency ordered Kinder Morgan to reexamine the pipe and make repairs. The agency closed out its corrective actions in 2010, PHMSA documents show.
In recent interviews, the agency first said its investigation was closed, then said a probe was under way by the federal Inspector General's Office, and finally said PHMSA itself was still conducting an inquiry.
"We have not completed our enforcement action," Quarterman said.
Carl Weimer, executive director of the Pipeline Safety Trust, the nation's leading advocacy organization for tougher pipeline regulation, said the case showed PHMSA's foot-dragging even when faced with clear failures by the industry.
"This is the classic case," Weimer said, "in which you warn someone and it's obvious they didn't take the warning to heart."