Wednesday's Denver Post (CO) reported that state regulators have stopped work at the Lowry Air Force base clean-up site due to a billing dispute. The article implies state regulators have walked off the job (purportedly as they have done at least twice before):

The Colorado Department of Public Health and Environment will not go back to work until the Air Force pays $100,000 for state cleanup work conducted since September, state health officials said Tuesday.

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In 2002, the Air Force privatized much of the cleanup work on site, turning management over to the Lowry Redevelopment Authority, a nonprofit organization established by Aurora and Denver to oversee the redevelopment.

[...]

While the authority has completed much of the work, it needs the state health department to review technical data from the cleanup to move forward.

An Associated Press follow-up story clarifies that clean-up work has not stopped. The dispute has merely caused the delay of state approvals, something that could impact the clean-up down the road:

Lowry Redevelopment Authority spokeswoman Hilarie Portell told The Associated Press Wednesday that work at the site has not be held up by the dispute.

“Our cleanup is moving forward,” she said, but will eventually require reviews and approvals by state regulators.