CHARLOTTE, N.C. (AP) — A Charlotte engineering firm estimates repairs to a nuclear reactor in Florida could cost more than $3 billion and take eight years to complete.

The Charlotte Observer reported (http://bit.ly/SAey1K) estimates by Zapata Inc. came at the request of Duke Energy, which inherited the plant in Crystal River, Fla., when it completed a merger in July with Raleigh-based Progress Energy.