Massey Energy owned and operated Upper Big Branch Mine where 29 miners were killed in April 2010 . The Mine Safety and Health Administration found that the company 's culture of favoring production over safety contributed to flagrant safety violations that caused the coal dust explosion . It assessed $ 10.8 million in fines for 369 citations and orders , the largest for any mine disaster in U.S. history . Alpha Natural Resources additionally settled Massey 's potential criminal liabilities for $ 209 million
Upper Big Branch Mine
Upper Big Branch Mine disaster
Massey Energy