Dayton, Ohio — A contractor on the 1,679-mile Rockies Express natural gas pipeline is under federal investigation amid allegations by former project inspectors that crews from Georgia-based Latex Construction Co. failed to install required equipment designed to prevent breaches that could trigger explosions.

The owners of the Rockies Express, or REX, had negotiated with Latex of Conyers to work on the upcoming eastern leg of the pipeline, but now don't plan to use the company, said REX spokesman Allen Fore. He declined to discuss the reason.

TY GREENLEES/Cox News Service (ENLARGE)

These are pipes for the Rockies Express natural gas pipeline project that are stored near Interstate 71 in Clinton County, Ohio.

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The pipeline, which will bring gas from Wyoming to the Midwest and East, is complete from Colorado to Kansas, and will soon be operational to central Missouri. Federal approval is expected soon for the eastern phase of the project through Ohio.

Officials of the Transportation Department's pipeline safety office confirmed allegations that Latex crews in Kansas didn't properly install concrete river weights that fit over the 42-inch pipeline at water crossings to keep it from floating. The officials said they made Latex install missing weights in a couple of areas. Officials are still investigating claims that Latex didn't wrap pipeline in a coating to protect it from rock damage.

The federal investigation confirmed inspectors' assertions that Latex crews dug a trench and buried some river weights that were delivered to the job site, Fore said. Latex owner William Honey said they were extras that weren't needed.

"It doesn't affect the integrity of the pipeline," Honey said, but "we made a mistake. We did the wrong thing. Are we responsible? Yes we are, and we'll take our lumps."

Pipeline safety officials said river weights and rock coatings help prevent breaks in the pipe and, in a worst-case scenario, explosions. An explosion on the REX project in Wyoming killed a worker for another contractor with a fireball that reached 3,000 degrees.

"God help the people in Kansas, because you can write this down and quote me: There will be a catastrophic failure," said Matthew Burns of Columbus, one of the former REX inspectors who complained about Latex's work on a 105-mile section.

The allegations were raised by former Latex safety coordinator Don Stewart of Green Bay, Wis., who said he resigned in September after three months because of Latex's "careless, wanton, reckless unconcern for human safety."

Stewart, Burns and another former REX inspector said they quit because Latex crews pressured them not to report shoddy work and accidents, even issuing threats and offering bribes. Stewart said REX's owners brushed him off when he reported problems with Latex last fall.

Fore said the owners took the allegations seriously.

"It's in no one's interests to construct a pipeline that's not completely safe," he said.

Latex still could join the project next year, Honey said. A spokesman for the owners of REX agreed that's possible.

"I'm not ashamed of the job we did" on a 105-mile construction spread near Hiawatha, Kan., Honey said. "It's just not a perfect world, it's not a perfect environment. This work is done by people, and people do things they shouldn't do."

Latex hired 600 union tradesmen working six days a week for the nearly six-month job, which concluded early this year.

The former safety inspectors, who worked for three separate companies, said Latex crews were more concerned about meeting REX's ambitious construction deadlines than ensuring safety for workers and the public. They said workers hid infractions from them and tried to intimidate them so they wouldn't report problems.

"I've never come across any kind of contractor that would just blatantly threaten you, flatten your tires. Just unbelievable," said former REX inspector Matthew Burns of Columbus, Ohio. "The inspectors are scared."

Former REX assistant chief inspector Cecil Mashburn said he and his two sons, who also were REX inspectors, quit in September because of routine safety breaches and intimidation by Latex workers.

"We had people come up and say, 'They'll bury you somewhere,' " Mashburn said. "It was hide-and-go-seek on everything [to find violations]. This is the worst experience I've ever had in my life and I've worked in the Ukraine and Indonesia, all over the world."

Mashburn said he became suspicious that workers were illicitly burying river weights designed to anchor pipeline at water crossings when he learned that workers were digging at 2 a.m. one day. Transportation Department investigators later confirmed that Latex buried river weights.

Stewart, the former Latex safety coordinator, first brought a litany of allegations to the Occupational Safety and Health Administration in October. Stewart said workers nearly struck an existing pipeline with heavy equipment, "narrowly avoiding a catastrophic explosion." He also accused Honey of ordering him to rewrite a report critical of the foreman and the equipment operator, but he refused.

"I have no recollection of that," Honey said.

Stewart said workers collapsed a bridge by ignoring weight limits, had a near-collision with a freight train when they improperly crossed a railroad track with earth movers, clipped power lines and flipped two earth movers "while working without supervision in the dark." There were also many injuries of workers, he said. "Many of these incidents were initially hidden from me so I could not report them."

When workers wanted to keep inspectors out of an area, they'd block it off with a dirt berm so only heavy equipment could enter, he said.

After Stewart resigned Oct. 25, Latex worker Brian Hawkins was partially crushed and critically injured when three huge pipe sections slipped from a boom and fell on him. Doctors had to amputate his leg.

Stewart said he reported the problems with Latex to Kinder Morgan Energy Partners, REX's majority owner. Company officials investigated, he said, but took no action. "They refuse to rein in this contractor because all they want is to get gas flowing in that new line so they can get their $4.5 billion [investment] back," he said.

REX spokesman Fore said the pipeline wasn't compromised, and it's tested thoroughly before it goes on-line and carefully monitored thereafter.

He declined to say whether Latex's contract allowed for extra pay for beating deadlines.

"All we need to do is check at the gas pump to know there's an energy crisis," Fore said. "There is an urgent need for these kinds of projects to move forward."

But Mashburn said timetables should never compromise safety.

"We're inspecting today for something that could happen 20 years from now," he said. "I want to do it by the book. It's your kids and my kids who might get killed."