Looking south from the Wells Overlook tower, this photograph from May 2010 shows construction on a stretch of the new U.S. Highway 59. This area is on Pleasant Grove Hill, south of County Road 458 and east of the current U.S. 59.

Construction crews are busy digging up and hauling away enough dirt from Pleasant Grove Hill to fill a massive eight-story building — all so that the exposed earth south of Lawrence can sleep until next summer, before snuggling under a blanket of crushed rock and asphalt pavement designed to carry thousands of vehicles along a new U.S. Highway 59.

“We’re trying to avoid a ‘rebound’ effect,” said Jason Van Nice, construction manager for the Douglas County portion of the $240 million highway project, which runs from Lawrence to Ottawa. “When you take 80 feet of material off that hill, it’ll want to expand. …

“It’s like taking a stack of books off your mattress: It comes back up. We want to get all the expansion out of the ground before we put the highway on top of it.”

As the exposed hillside slumbers, crews will be busy finishing interchanges, bridges and other features south of North 650 Road, Van Nice said. Excavators then will return to the hillside in August 2011, to prepare the area for construction beginning in early 2012.

The Douglas County portion of the U.S. 59 project will be expected to start carrying traffic by spring 2013, Van Nice said. The section in Franklin County opened earlier this year.