Finding concrete problems at Denver International Airport

DIA runways meant to last decades, but repairs cast shadow on defunct company

Lou Kilzer And Alan Gathright, Rocky Mountain News

Saturday, July 15, 2006

Runways and taxiways at Denver International Airport that were built by a contractor caught diluting concrete and faking quality tests during airport construction will be undergoing major repairs decades short of their life expectancy.

DIA plans to replace 1,287 of the massive concrete panels constructed by Ball, Ball and Brosamer, known in the industry as the 3Bs.

Planned repairs will cost $30.6 million, with most of it going to rebuild the 3Bs' sections.

The airport began replacing the concrete this spring and would like to finish by the end of 2007.

At the Colorado Springs Airport, meanwhile, officials this year concluded that one runway built in 1991 by the 3Bs had deteriorated to the point that it is being demolished and rebuilt at a cost of $37.7 million.

The stakes are not just measured in dollars and cents.

Crumbling concrete is a life-or-death issue. If an aircraft engine sucks in debris at takeoff, it could crash.

Whether the two Denver runways in question will eventually need replacement on the magnitude of the one in Colorado Springs is not known, and they will be part of a 13-month study recently launched by the airport.

DIA Manager Turner West said runways are inspected at least twice daily to ensure safety. He described one recent incident in which an airliner was throttling up for takeoff "and here this piece of concrete comes up."

The runway damage was repaired immediately, he said.

The manager said DIA hasn't found anything alarming about the condition of its concrete.

But he said there is something of a "Bermuda Triangle" mystery about possible causes for its deterioration. The new study is expected to provide answers.

As for the 3Bs, West said, "I have basically worn the subject out. And I have yet to have anyone tell me that they feel like there's anything out of the ordinary about our concrete."

However, a formerly sealed California lawsuit obtained by the Rocky Mountain News paints a picture of deception, fraud and bribery, which casts a long shadow over Ball, Ball and Brosamer's work at DIA and other airports.

At the conclusion of a federal whistle-blower lawsuit against the 3Bs, the firm was penalized for mixing more sand and gravel into the concrete mix to save on cement costs as it worked at DIA.

A former 3Bs concrete manager acknowledged in a deposition for the lawsuit that the company was forewarned about inspections at DIA and would scramble to dump more cement into the mix by the time inspectors arrived.

They called the practice "sweetening."

He and others also said the company rigged computer formulas to add cheaper ingredients when inspectors were not around. Like the dishonest butcher who manipulated the weight of meat on his scale, company personnel called the practice "fat fingering," according to documents reviewed by the News.

Sworn statements given during the litigation of the lawsuit allege the company did the same thing at Colorado Springs Airport and John Wayne International Airport in Orange County, Calif.

DIA officials said their consultant is exploring several factors that can contribute to concrete cracking. They include Colorado's freeze-and-thaw cycles and shrinkage that occurs when fresh concrete lacks water or sets in dry heat.

The damage also can be caused by a destructive chemical process called alkali-silica reaction, or ASR - which experts say is exacerbated by de-icing solutions - that's plaguing several major airports nationwide.

Colorado Springs and Federal Aviation Administration officials believe de-icer is a culprit in the damage there.

But the whistle-blowers who first tipped officials to alleged bribery and fraud by Ball, Ball and Brosamer say what's happening at the two Colorado airports proves their point.

They were right when they said a decade ago that the runways would never reach their 30 to 40 years of expected life, said their Washington, D.C., lawyer, Peter Chatfield.

"My clients were vindicated by the whole circumstances," he said.

FAA refused payment

DIA officials are playing down the chances that their runways could crumble like the one in Colorado Springs, with their lead study scientist going so far as to say that the Springs airport may have acted precipitously.

But Denver will start ripping up more than 1,200 panels constructed by the 3Bs.

That compares to fewer than 300 for the other three runway contractors combined.

The FAA says a survey found suspected ASR damage on DIA runways.

Tests on concrete core-samples confirmed that "that ASR distress was prevalent in concrete pavements at Denver International," according to Prasad Rangaraju, a civil engineering professor at Clemson University, who is conducting FAA-funded research.

Chatfield says the FAA's response is disingenuous.

He noted that the FAA specifically refused to pay for work by the 3Bs at DIA because of the allegations of rigged tests and fraud, and that its current position "seems kind of inconsistent."

At any rate, Chatfield noted that the chemical reaction theorized by the FAA is not affecting DIA's runways equally.

"It's 3Bs' stuff that's going bad," he said.

"And they are the ones who were accused of messing with the recipe."

For his part, Bob Brosamer, a former 3Bs owner who helped oversee the Colorado Springs project and the start of the one at DIA, says the company is not to blame for the deteriorating runways.

Springs officials insisted that the company use rock from an unproven source as part of the concrete mixture, he says.

And problems with DIA concrete were not caused by changing the concrete recipe.

Instead, Brosamer said, they are merely the consequence of aging. He described the costs of repairs at DIA as "just peanuts."

Rigged tests discovered

Ball, Ball and Brosamer was a major California-based paving contractor when it entered the Colorado aviation construction business, with its first job being Colorado Springs runway 17L/35R, built in 1991.

DIA construction was just under way, a keystone achievement of Federico Peña's tenure as Denver's mayor.

The 3Bs soon landed five large DIA contracts, including two runways, two concourse aprons and a perimeter taxiway.

It wasn't long before the 3Bs began angering its DIA subcontractors with erratic payroll practices, including a Minnesota firm named CSI.

CSI hauled rock aggregate at DIA for the 3Bs and found itself in a financial straightjacket because 3Bs wouldn't pay, according to several court filings.

Company President Steve Chaves and its top concrete specialist Doug Ruder began investigating why the 3Bs were not crediting CSI for all the rock it hauled.

To prove its case, Ruder looked through "batch tickets" Denver had collected detailing the concrete mixtures at DIA.

What he found, he said, shocked him.

The batch tickets, he said, showed that 3Bs was rigging tests to hide a concerted policy to short cement in its mixtures.

Soon, Ruder and Chaves were meeting with the FBI and Denver officials.

Ruder said in papers filed in the whistle-blower lawsuit that after he presented officials with the concrete reports in early 1993, officials were alarmed but sought more test results.

He and Chaves went to gather them.

Ruder later testified that he personally went to take a concrete core sample in the middle of a 3Bs runway when he was approached by a 3Bs official who challenged him.

When Ruder didn't back down, the official offered him a $500,000 job "requiring little or no work if Ruder would walk away from CSI and join BBB then and there," according to a statement Ruder's lawyer gave to the Department of Justice.

Ruder declined.

At the next meeting with Denver officials, Ruder said, the mood had shifted.

He met outside a meeting room with a city manager who told him the city had ordered him and others to distance themselves from the allegations "because Denver could not afford the bad publicity," according to court papers.

In the coming months and years, city experts would say one thing while experts for the whistle-blowers and the federal government would say another.

The FBI also became involved, as did a Denver federal grand jury.

But Chaves and Ruder were wary that not much would come of the local effort.

Peña had become President Clinton's secretary of transportation, and there was was a lot of local pride - not to mention billions of dollars - riding on DIA's success.

By this point, the massive project had become a political liability as construction foul-ups and design changes triggered two-year delays and a $1 billion cost overrun. DIA had become the butt of late-night comedy jokes.

In any event, the whistle-blowers filed their suit in San Francisco and asked the U.S. Attorney's Office there to join as a plaintiff in alleging that the 3Bs had fraudulently manipulated concrete tests at DIA and Colorado Springs.

Ruder and Chaves, bankrupted in the pay dispute with 3Bs, wound up taking $130,000 total from the settlement of the whistle-blower suit, which netted the federal government $300,000. They won $3 million from 3Bs in a separate lawsuit, which they used to pay off creditors.

Denver chose not to sue the 3Bs or demand that the suspect concrete work be replaced, something that could certainly have caused more delays and concern to DIA's bond holders.

Instead, Denver decided to withhold $2.3 million for work it said did not meet standards. That was a small fraction of the $138 million the city paid the firm.

Runway shut down

Colorado Springs Aviation Director Mark Earle says that when he arrived at his job three years ago, he inherited the crumbling north-south runway.

He had no idea what was going on, but he knew he had his hands full.

Crews, he said, "were going out every few days and closing the runway at night and patching the runway and the adjacent taxiway."

As costs skyrocketed and the safety issue grew, Earle said managers huddled with FAA officials until they collectively decided that the only reasonable solution was to replace the entire runway.

They had concluded that ASR, exacerbated by de-icing compound, was contributing to the deterioration.

But whatever the cause, there was no time to waste, Earle said.

Despite the inconvenience, the runway - one of three that serve Colorado's second-largest city - was closed.

Earle said the FAA never told him about the 3Bs' problems in Denver, and he didn't know of the San Francisco suit that alleged the company shorted cement in it Colorado Springs runway.

Now, he said, he will review everything, including the 3Bs' work.

"We'll certainly be looking at it," Earle said.

"That's something that the city attorney's department would be interested in as well as the airport," he said. "And we would, of course, be interested in having a discussion with the FAA about it."

While Colorado Springs rebuilds its runway, Denver has hired DMJM Aviation to determine if there was bad concrete poured at the airfield.

Michael McNerney, chief scientist for that project, doesn't think that cracking concrete will prove to that big of a problem at DIA, although his study has another 12 months to run.

"There have been people who have claimed that they think that it's a problem," McNerney said.

"I particularly don't think we have a big problem. I think we have no more a severe problem than most any other airport."

Despite his doubts, McNerney said he will conduct his probe with scientific objectivity.

Science aside, Brosamer says there was no problem at DIA.

"I don't think the allegations are true," he said. "I feel very strongly there."

He also noted that Ball, Ball and Brosamer went out of business more than five years ago.

Funding in doubt

Denver's $30.6 million, two-year plan to replace concrete panels is in addition to the roughly $3 million it spends annually for more routine runway maintenance.

Denver replaced a total 121 concrete panels - ranging in size from about 19 feet by 20 feet to 25 feet by 25 feet - between 1999 to 2005, or some 17 a year.

That's slated to jump to more than 1,100 panels next year - all but a handful on 3Bs' runway-taxiway systems.

DIA officials stress that repairs on 3Bs' paving is clustered on taxiways, not the runways themselves, where a jetliner taking off at full-throttle would be at greatest risk of sucking in debris.

However, damage is concentrated on several high-speed taxiways, where landing aircraft exit runways at 65 mph.

Ruder said the first areas he expected to see concrete problems would be high-speed turnoffs to taxiways, where a landing plane exerts extreme G-forces. In fact, those are the areas where Denver plans most of its work on the 3Bs' project.

DIA officials said they expect the price tag to grow beyond $30.6 million, adding they'll know more after McNerney completes his study.

But doubts about securing federal funding are already slowing the rehabilitation project this year, and that means plans to revamp the two 3Bs' runway-taxiway complexes could be pushed beyond 2007.

What will maintenance crews do if they find hazardous concrete fragments before replacement money arrives?

Securely patch it with epoxy, airport officials say.

One thing both Denver and Colorado Springs point out is that their airfields - regardless of any concrete problems - were certified by the FAA.

While the FAA refused to reimburse the 3Bs' work because it failed to meet concrete specifications in some tests, the agency determined the overall quality was not impaired and approved the runways.

"Regardless of the 3Bs issue, the final (DIA) runway product met the FAA standards for safety and strength," said Jack Scott, the top pavement engineering expert for the FAA's Northwest Mountain Region.

He declined to speculate about what's causing DIA's runway deterioration, deferring instead to the airport's ongoing study.

Dulce Rufino, another expert pavement engineer, disagreed, saying that if allegations that 3Bs significantly shorted on cement are true, "that would definitely decrease the life of the pavement" on DIA runways.

"You'd expect more cracking, because the cement is one of the main components that gives concrete its strength," said Rufino, an Applied Research Associates engineer and pavement expert who serves on the Transportation Research Board of the National Academy of Sciences.

Concrete strength is critical to helping runways withstand the constant pounding of 400-ton jumbo jets, she said.

Scott said he knows what destroyed the Colorado Springs runway: ASR, alkali-silica reaction.

Airport experts thought they'd tamed the destructive chemical reaction, which naturally occurs in concrete mixtures containing highly alkali cement and silica in sand and gravel.

It creates a white goo that swells up, absorbing rain water, eventually causing concrete to crack and crumble.

Tests were developed to guard against ASR in the 1980s.

But research by Clemson's Rangaraju has shown that an environmentally friendly pavement de-icing chemical - potassium acetate - introduced in the early 1990s accelerates ASR in some concrete runways. The FAA has provided funds for a nationwide study to review the potential of the ASR problem.

DIA officials, however, are skeptical about whether de-icers are causing their concrete problems.

One thing all sides agree on: The need to prevent loose concrete from triggering a catastrophic accident.

"It's very dangerous," Rufino said.

Airports and the FAA are so wary of stray objects striking aircraft that DIA is required to control its wildlife population, including rabbits that can attract hungry eagles and hawks, DIA spokesman Chuck Cannon said.

"If those (birds of prey) get sucked up in an engine, you can have a big problem," he said.

"If you are afraid of birds going into the engine," Rufino said, "imagine a piece of concrete. That would be very damaging. It could cause an accident with hundreds of people in a plane. So, it's a safety issue."

The hazard was illustrated less than two weeks after DIA opened in 1995.

A United Airlines 737 taxiing to the gate sucked up slivers of concrete, estimated to be one-sixteenth of an inch thick, damaging the jet's turbine blades. Passengers were transferred to another plane.

Officials suspected it was leftover concrete that had been spilled atop the finished slabs.

Worse in the middle

To attorney Chatfield, the jury came in long ago.

He said whistle-blower Ruder would laugh at the quality control inspectors overseeing the DIA runway construction.

"When the inspectors were coming, they drove these little yellow trucks with flashing lights," Chatfield said.

"And the airport is so huge that they could see them coming for minutes before they got there.

So they could manipulate (the concrete mix) until the guy was almost there and then they could stop for just long enough for when that guy came and sampled the concrete to get a good sample . . ."

Ruder, moreover, suspects that the weakest concrete was being poured in the middle of the runways.

There workers could conceal diluted, more fluid concrete because it would be contained by the firmer, setting panels surrounding it - instead of "slumping."

"It wouldn't be obvious to anyone looking at it that anything was wrong with it," Chatfield said.

According to the successful lawsuit against 3Bs, the mid-runway cores samples taken by Ruder "turned out to be the worst cores."

The city said it didn't act on those results because nothing, in fact, was wrong.

But not everyone in the city accepted 3Bs' work as beyond reproach. When Denver reached its 1995 decision to dock 3Bs $2.3 million for concrete that didn't meet specifications, a hearing officer agreed. The 3Bs, he said, "readily admits" it failed to follow proper quality control.

And in a statement that could be prophetic, hearing officer Edward J. Blieszner said: "Portions of the runway with lower strength concrete may be perfectly safe, but may simply require replacement sooner than the design life of 40 years used at DIA."

By the numbers

1,287 Number of massive concrete panels on runway complexes that need to be replaced that were built by Ball, Ball and Brosamer - known in the industry as the 3Bs. Denver International Airport would like the repair project finished by the end of 2007.

$30.6 million Estimated cost of the repairs. Most of the money will go to rebuild the panels built by the California-based 3Bs.

$138 million Amount Denver paid the 3Bs, which is no longer in business, to build the runways. It initially withheld $2.3 million for work it said did not meet standards.

$37.7 million Amount Colorado Springs Airport will spend to demolish and rebuild a 15-year-old runway, built in 1991 by the 3Bs.

kilzerl@RockyMountainNews.com or 303-892-2644; gathrighta@RockyMountainNews.com or 303-892-5486