BOISE, Idaho (AP) — Federal officials say a small-scale version of a key component of an eastern Idaho radioactive waste treatment facility that has so far failed to operate will be tested in Colorado.

The U.S. Department of Energy on Thursday said Engineers at Hazen Research near Denver in January will start testing a smaller replica of the primary reaction vessel that's part of the $600 million Integrated Waste Treatment Unit at the Idaho National Laboratory.

The failure of the treatment facility to process 900,000 gallons of high-level nuclear waste has caused the federal agency to violate a 1995 agreement with Idaho. Idaho Attorney General Lawrence Wasden as a result is refusing to allow research quantities of spent nuclear fuel from entering the state to be tested at the laboratory.