The federal government recently doled out two “green findings” to the Northwest’s only commercial nuclear reactor.

The Columbia Generating Station, near Richland, is run by the utility Energy Northwest.

Green findings are the lowest infractions for the nuclear industry, but it’s not the only time the plant’s been in trouble. The plant has also been warned by the Nuclear Regulatory Commission (NRC) in the last few years for several unplanned shutdowns, or scrams.

Now the NRC says 15 out of 51 control room operators failed a portion of their re-qualification examinations on a recent inspection. And two of eight crews failed testing on plant simulators -- the computerized system that mimics the control room where the workers have to respond to made-up challenges.

DOCUMENT: NRC letter to Energy Northwest

The plant successfully addressed the issue by retraining, retesting and requalifying those operators before they were allowed to return to their control room duties.

Energy Northwest got another green finding when security officers failed to perform some required hourly fire inspections of a pump room for as long as two days.

Victor Dricks , an NRC spokesman, says that the agency's rigorous inspection program is designed to identify performance deficiencies before they become significant enough to affect plant safety -- and green findings are common. These two findings are the lowest of four-different levels the NRC records.

Energy Northwest has taken corrective actions to address both issues, mostly by retraining operators. The NRC has checked off on that work.

An Energy Northwest spokesman says the NRC allows for a 20 percent failure rate of the operator tests -- and the utility exceeded that by 5 percent. And no one who fails the tests can be in the operator room of the plant -- sort of like having your driver’s license suspended.

DOCUMENT: NRC letter to Energy Northwest

CORRECTION: This story has been updated to correct the spelling of Victor Dricks' name.