X0204 3 2012-03-05 1 0001441849 CLOUD PEAK ENERGY INC. CLD 0001543888 Condon Patrick J. 505 S. GILLETTE AVE. GILLETTE WY 82716 1 Exhibit 99.1 - Power of Attorney /s/ Amy J. Stefonick, attorney-in-fact for Mr. Condon 2012-03-06