Document/ExhibitDescriptionPagesSize
1: S-1 Registration Statement (General Form) HTML 2.13M
2: EX-3.1 Articles of Incorporation/Organization or By-Laws HTML 18K
3: EX-3.3 Articles of Incorporation/Organization or By-Laws HTML 31K
4: EX-10.1 Material Contract HTML 49K
13: EX-10.10 Material Contract HTML 39K
14: EX-10.11 Material Contract HTML 44K
15: EX-10.12 Material Contract HTML 55K
16: EX-10.13 Material Contract HTML 61K
17: EX-10.14 Material Contract HTML 113K
18: EX-10.15 Material Contract HTML 36K
19: EX-10.16 Material Contract HTML 36K
20: EX-10.17 Material Contract HTML 37K
21: EX-10.18 Material Contract HTML 34K
22: EX-10.19 Material Contract HTML 303K
5: EX-10.2 Material Contract HTML 43K
23: EX-10.20 Material Contract HTML 21K
6: EX-10.3 Material Contract HTML 38K
7: EX-10.4 Material Contract HTML 41K
8: EX-10.5 Material Contract HTML 42K
9: EX-10.6 Material Contract HTML 37K
10: EX-10.7 Material Contract HTML 35K
11: EX-10.8 Material Contract HTML 58K
12: EX-10.9 Material Contract HTML 45K
24: EX-23.1 Consent of Experts or Counsel HTML 11K
25: EX-23.2 Consent of Experts or Counsel HTML 11K
26: EX-23.4 Consent of Experts or Counsel HTML 12K
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Exhibit 23.1
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We hereby consent to the use in this Registration Statement on Form S-1 of our reports dated August 12, 2009
relating to the financial statements of Rio Tinto Energy America Inc. and Subsidiaries and Cloud Peak Energy Inc. which appear in such Registration Statement. We also consent to the
reference to us under the heading "Experts" in such Registration Statement.
/s/
PricewaterhouseCoopers LLP
Denver, Colorado August 12, 2009