THIRD AMENDMENT TO CREDIT AGREEMENT

Exhibit 10.1

THIRD AMENDMENT TO CREDIT AGREEMENT

Recitals:

A. Bank and each Borrower have entered into that certain 2005 Amended and Restated Credit Agreement dated as of July 29, 2005, that certain First Amendment to Credit Agreement dated October 22, 2007, and that certain Second Amendment to Credit Agreement dated October 2, 2010 (as amended, and as amended, modified, or supplemented from time to time in the future, the “Credit Agreement”) pursuant to which the Lender has extended certain credit facilities to Borrower under the terms and conditions set forth in the Credit Agreement.

B. Borrower has requested that the Bank extend the term of the loan, which the Bank is willing to do under the terms and conditions as set forth in this Third Amendment to Credit Agreement (“Third Amendment”).

Agreement:

Now, therefore, in consideration of the mutual covenants and agreements herein contained and other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the parties hereto hereby agree as follows:

1. Amendments to Credit Agreement. The Credit Agreement is amended as of the Effective Date as follows:

1.1 Section 1.90 is amended to read as follows:

1.90 Revolving Maturity Date: means November 16, 2012.

2. Conditions to Effectiveness of this Third Amendment. The effectiveness of this Third Amendment is subject to satisfaction, in the Bank’s sole discretion, of each of the following conditions precedent (the date on which all such conditions precedent are so satisfied shall be the “Effective Date”):

2.1 Delivery of Executed Documents. Borrower shall have delivered to the Bank the following document:

A. This Third Amendment, duly executed by each Borrower.

2.2 Representations and Warranties. The representations and warranties of Borrower in the Credit Agreement shall be true and correct in all material respects on and as of the Effective Date as though made on and as of such date.

2.3 No Event of Default. No Event of Default shall have occurred and be continuing under the Credit Agreement as of the Effective Date of this Third Amendment.

2.4 Payment of Fees and Expenses. Borrower shall have paid the Bank, by wire transfer of immediately available federal funds (a) all fees presently due under the Credit Agreement (as amended by this Third Amendment); and (b) all expenses owing as of the Effective Date pursuant to Section 13.1 of the Credit Agreement.

3. General Provisions.

3.1 No Other Modifications. The Credit Agreement, as expressly modified herein, shall continue in full force and effect and be binding upon the parties thereto.

3.2 Successors and Assigns. This Third Amendment shall be binding upon and inure to the benefit of each Borrower and the Bank, and their respective successors and assigns, except that Borrower may not assign or transfer its rights or obligations hereunder without the prior written consent of the Bank.

3.3 Definitions. Capitalized terms used, but not defined, in this Third Amendment shall have the meaning set forth in the Credit Agreement.

3.4 Severability. Should any provision of this Third Amendment be deemed unlawful or unenforceable, said provision shall be deemed several and apart from all other provisions of this Third Amendment and all remaining provision of this Third Amendment shall be fully enforceable.

3.5 Governing Law. To the extent not governed by federal law, this Third Amendment and the rights and obligations of the parties hereto shall be governed by, interpreted and enforced in accordance with the laws of the State of Colorado.

3.6 Headings. The captions or headings in this Third Amendment are for convenience only and in no way define, limit or describe the scope or intent of any provision of this Third Amendment.

3.7 Counterparts. This Third Amendment may be executed by the parties hereto in separate counterparts, each of which, when so executed and delivered, shall be an original, but all such counterparts shall together constitute one and the same instrument. Each counterpart may consist of a number of copies hereof, each signed by less than all, but together signed by all, of the parties hereto. Copies of documents or signature pages bearing original signatures, and executed documents or signature pages delivered by a party by telefax, facsimile, or e-mail transmission of an Adobe^® file format document (also known as a PDF

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file) shall, in each such instance, be deemed to be, and shall constitute and be treated as, an original signed document or counterpart, as applicable. Any party delivering an executed counterpart of this Third Amendment by telefax, facsimile, or e-mail transmission of an Adobe^® file format document also shall deliver an original executed counterpart of this Third Amendment, but the failure to deliver an original executed counterpart shall not affect the validity, enforceability, and binding effect of this Third Amendment.

[Signatures to follow on next page.]

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IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment to be executed as of the Effective Date.

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