RANDALL CHASE
Associated Press

DOVER, Del. (AP) — State officials say samples from a massive mound of dirt believed to have caused a nearby interstate bridge in Delaware to tilt show no dangerous contaminants.

State environmental official Tim Ratsep said Monday that test results on the dirt showed only low levels of polyaromatic hydrocarbons, or uncombusted carbon. He said that is typical of soils next to roadways because of asphalt.

The finding cleared the way for officials to approve storage of the dirt on a developer-owned parcel in south Wilmington.

Official believe the weight of the dirt caused columns supporting the Interstate 495 bridge to tilt, forcing its emergency closure that started last week.

With the dirt mound removed, engineers are focusing on shoring up the bridge so that it is safe to carry traffic again.

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