The U.S. Army has asked the state to expedite its billing for damages that one of its excavators caused to a pedestrian overpass on Sept. 5.

In addition to the cost of replacing the footbridge, the Army will also have to pay costs associated with a freeway closure that snarled traffic so badly some motorists were stuck in their cars for up to eight hours. Those additional expenses include overtime costs and equipment needed to block off the on-ramps.

"We're trying to put everything together as quick as we can," said state Department of Transportation spokesman Scott Ishikawa.

Dana Viola, special assistant to the state attorney general, said the Army had asked to be billed as soon as possible. Repairs to the footbridge alone could cost $500,000.

Ishikawa's office received about 20 calls criticizing the state's decision to shut down the freeway after the accident, but he said the state had good reason to fear that 60,000 pounds of concrete could come crashing down on the H-1.

"We were concerned that vibrations along the freeway viaduct caused by the traffic would have shaken more of the concrete pieces loose, and possibly causing the mauka side of the walkway to come down," Ishikawa said.

He said he received 10 calls complimenting the state for removing the walkway in one night and 20 more suggesting alternative routes, should the freeway have to be shut down in the future.

Ishikawa said the freeway will have to be closed again to repair the footbridge, but the plan is to build the missing piece of walkway elsewhere to minimize the time the freeway will be closed.

Meanwhile, state transportation and Civil Defense officials began meeting yesterday to devise a plan to reverse traffic during emergencies to avoid a repeat of the massive traffic jam.