Officials still searching for cause of contaminated fuel

HAMPTON, Ga. -- The contaminated fuel that caused Denny Hamlin's car to stall near the end of Sunday's race at Atlanta Motor Speedway might have been added to the car's fuel tank as early as Friday morning, according to Nextel Cup director John Darby.

Speaking Monday during a two-day test session, Darby said NASCAR and Sunoco are actively pursuing the cause of the contaminated water that affected "more than two and less than 43" of the cars in the Pep Boys Auto 500.

Sputtering Hamlin

Denny Hamlin's inability to get going on a late-race restart was due to another liquid that was found in the fuel cell.

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"Obviously, we're pumping out of the same pumps, the same tanks [during Monday's test] as we did [Sunday] with no issues," Darby said. "The way, typically, any amount of water that winds up, especially from dispensing the fuel, typically will settle out of suspension, showing up with the very first fills of the event. What our suspicions are is that some of the very early gas that was pumped out as early as Friday morning could have been where the contamination started."

Darby has asked Nextel Cup teams to systematically disassemble their fuel filters and fuel cells from the cars involved in Sunday's race, in order to determine how widespread the problem might be. In addition, he's asking Craftsman Truck Series teams -- who also fueled from the pumps over the weekend -- to report on anything out of the ordinary.

"For example, our race winner [Sunday] night, in post-race inspection, we did find some evidence of some water in the fuel," Darby said. "Obviously, from a performance standpoint, there wasn't an issue. [Then there was] a high level of contamination that we did find in a couple of cars, such as [Dave Blaney] and [Hamlin],where there was enough introduced into the fuel system that could potentially create some performance deterrents."

Darby said the water that entered the system was a cloudy brown color. NASCAR, Sunoco and independent labs are now testing the substance to see what it might be -- and where it might have come from.

"It's a brownish-colored water," he said. "Typically, if it was just water, it would appear to be more clear. What the residue in the water can help us understand is if it's come from a failed pipe or a pump or some other source that could allow that to enter the fuel."

Since the fuel in the underground tank continues to test clear of contamination, Darby said the focus of the investigation then moves on to the method of dispensing the fuel.

"You've got an underground tank," Darby said. "You've got plumbing that connects the underground tank to the fuel pump. And you've got the fuel pump itself. So that's where the investigation is going on now because it appears that what's in the ground in the tanks is very clean.

"So then what you look for is an area of the fueling system, whether it be the stand pipe, which connects the tank to the pump, or a pump hose, or the filtering system on the individual gas pumps, that may have picked up some water and let it pass from the pump to the cans the teams use."

It's quite possible, according to Darby, that this winds up being an anomaly.

"The introduction of what water we've seen has been in very small amounts, with the exception of a couple of cases," Darby said. "But those are the things that we're working with Sunoco to backtrack through to make sure. At the end of the day, was it one pump that had who knows what go wrong with it, or a way that the water was introduced, that for all practical purposes, may never show its face again."

Darby said NASCAR has ruled out sabotage -- and as to a conspiracy theory: "That puts that to rest because there's already way too many teams involved to select one that somebody didn't like. That helps to reinforce the teams' confidence in our security measures."

Darby also ruled out the idea that condensation could have been the culprit. Sunoco officials do routine daily inspections of the underground tank for water contamination.

"Condensation is always a concern and that's why there's such an extensive monitoring system inside the underground tanks," he said. "I think we've surpassed the amount of water that you could blame on condensation.

"What really has me puzzled is that it's not a real clear water. So once the laboratory reports come back from what the substance is and what's mixed with it -- Is it rust? Is it clay? Is it what? -- we don't know. I think that will help point us in a real good direction."