The Cutting Edge.

As Denver International Airport approaches the busy summer travel season, officials have shut one of DIA's six runways for nine weeks to replace deteriorating concrete.
Contractors will cut out and replace more than 400 17-inch-deep concrete panels on runway 8-26 while consultants continue to study the full scope of DIA's pavement problem.
A chemical reaction called ASR is a factor in premature deterioration of concrete at DIA, say aviation officials, and no one knows how much pavement might ultimately be impacted.
"It looks right now like we do have ASR issues on about 1 percent of our pavement," said DIA engineering director David Rhodes.