One substance acquired for the project did not meet federal standards and "could have resulted in a spill of up to 15,000 gallons of high-level radioactive waste," says the report, which was based on a five-month audit of the site’s activities.

Contractors purchased 9,500 tons of steel reinforcement bars that proved unusable when one of the bars broke during construction of the MOX facility. Workers had already installed 14 tons of steel bars at the facility, wasting $680,000 and delaying the site’s completion.

Energy Department auditors also uncovered problems with pipes, steel plates, and a $12 million "glovebox" that did not meet the site’s needs for dealing with radioactive material, the McClatchy Newspapers reported.

"The department did not provide adequate oversight of the prime contractors’ quality-assurance programs at Savannah River," the report says. "Particularly, the department did not adequately establish and implement processes to detect and/or prevent quality problems."

The National Nuclear Security Administration, the semiautonomous Energy Department agency that oversees the nation’s nuclear weapons complex, opposed the report’s conclusions "concerning the safety of the facilities" and "related cost impacts," NNSA Principal Deputy Administrator William Ostendorff wrote. The Nuclear Regulatory Commission had completed a more thorough safety review of the MOX site that deemed lapses to be of "low significance," he added