Two officers with the Raleigh County Sheriff's Office stand guard in front of the Upper Big Branch coal mine several days after the April 5, 2010, explosion that killed 29 workers in Montcoal, W.Va.
Credit Mark Wilson / Getty Images
The first investigative report about last year's coal mine disaster in West Virginia blames a corporate "culture in which wrongdoing became acceptable, where deviation became the norm" for the deaths of 29 Massey Energy mine workers.
The report was produced by an independent team of investigators appointed by former West Virginia Gov. Joe Manchin and led by Davitt McAteer, a former federal mine safety chief who has investigated other mine disasters in the state.