CLEVELAND -- The Nuclear Regulatory Commission released Tuesday its preliminary findings on how bad problems at the Davis-Besse nuclear power plant were.

NewsChannel5's Ted Hart reported that the NRC classifies performance deficiencies on a scale of four colors: green, white, yellow and red.

Davis-Besse was a red, indicating high-safety significance.

A month after being shut down for maintenance, inspectors found that leaking boric acid had eaten a six-inch hole in the lid of the reactor vessel.

Under the NRC's guidelines, a red finding results in strong action by the commission to improve plant performance.

First Energy said it's still hoping to restart the plant in April. But it's up to the NRC as to when that happens, and officials said it might be much longer before the agency is willing to say that First Energy has corrected all the deficiencies.

Keeping the plant closed longer could cost First Energy $10 million to $12 million a month.

The utility company now has 10 days to respond to the NRC's finding of a high-safety significance.