**Exhibit 21.1**

** **

**List of Subsidiaries**

 

The following is a complete list of the direct and indirect subsidiaries of Cloud Peak Energy Resources LLC, a Delaware corporation, including their respective states of incorporation, as of March 1, 2011:

 
| **Name**                                       | ** ** | **Jurisdiction** | ** ** | **Ownership** | ** ** |
|------------------------------------------------|------------|------------------|------------|---------------|------------|
|                                           |       |             |       |          |       |
| Antelope Coal LLC                         |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Caballo Rojo Holdings LLC                 |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Caballo Rojo LLC                          |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Cloud Peak Energy Finance Corp.                |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Cloud Peak Energy Services Company             |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Cordero Mining Holdings LLC               |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Cordero Mining LLC                        |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Cordero Oil and Gas LLC                        |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Decker Coal Company                            |       | Unincorporated   |       | 50            | %          |
|                                           |       |             |       |          |       |
| Kennecott Coal Sales LLC                  |       | Oregon           |       | 100           | %          |
|                                           |       |             |       |          |       |
| Montana Royalty Company Ltd.              |       | Unincorporated   |       | 50            | %          |
|                                           |       |             |       |          |       |
| NERCO Coal LLC                            |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| NERCO Coal Sales LLC                      |       | Tennessee        |       | 100           | %          |
|                                           |       |             |       |          |       |
| NERCO LLC                                 |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Northern Coal Transportation LLC          |       | Oregon           |       | 100           | %          |
|                                           |       |             |       |          |       |
| Prospect Land and Development LLC         |       | Oregon           |       | 100           | %          |
|                                           |       |             |       |          |       |
| Resource Development LLC                  |       | Washington       |       | 100           | %          |
|                                           |       |             |       |          |       |
| Sequatchie Valley Coal Corporation             |       | Tennessee        |       | 100           | %          |
|                                           |       |             |       |          |       |
| Spring Creek Coal LLC                     |       | Delaware         |       | 100           | %          |
|                                           |       |             |       |          |       |
| Venture Fuels Partnership                      |       | Colorado         |       | 50            | %          |
|                                           |       |             |       |          |       |
| Western Minerals LLC                      |       | Oregon           |       | 100           | %          |
|                                           |       |             |       |          |       |
| Wyoming Quality Healthcare Coalition, LLC |       | Delaware         |       | 33.3          | %          |

 

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