A joint venture that includes a Spokane construction company won a $106 million contract to finish a nearly 200,000-square-foot research facility at the Pacific Northwest National Laboratory in Richland – the largest contract in lab history, according to the U.S. Department of Energy.

Spokane-based Lydig Construction Inc. and George Grant Inc., of Richland, will complete three main buildings, a test track and an underground laboratory for PNNL’s Physical Sciences Facility, according to a department news release. Work on the complex, northwest of Horn Rapids Road and George Washington Way, starts in July.

The Physical Sciences Facility will be the largest of three new facilities that will replace lab and office space PNNL occupies on the south end of the Hanford Nuclear Reservation that will be vacated by 2011 to prepare for environmental cleanup.

It will house about 450 employees working on national security and energy research, such as developing ways to detect and characterize radionuclides to help stop proliferation of weapons of mass destruction, according to the release. The track, for example, will be used to test equipment for identifying WMDs as part of a program to select and install radiation-detection devices at ports and borders, said Greg Koller, a PNNL spokesman.

Founded in 1956, Lydig Construction has built science buildings for Washington State and Gonzaga universities and Spokane Community Colleges. It constructed Schweitzer Engineering Laboratories Inc.’s world headquarters, according to its Web site. A company representative could not be reached for comment.

A Pasco company broke ground on the facility in August. The Department of Energy, National Nuclear Security Administration and the U.S. Department of Homeland Security are paying for the facility, expected to open in 2010.