(F/K/A Crowfoot Development, LLC) Limited Liability Company Agreement

Exhibit 10.61

SECOND AMENDMENT TO ADA CARBON SOLUTIONS, LLC

(f/k/a CROWFOOT DEVELOPMENT, LLC) LIMITED LIABILITY COMPANY AGREEMENT

This SECOND AMENDMENT (" Amendment" ), dated as of March 6, 2009, is made by and among the undersigned and amends the Limited Liability Company Agreement of ADA Carbon Solutions, LLC (f/k/a Crowfoot Development, LLC), a Delaware limited liability company (the " Company" ), entered into October 1, 2008 (as previously amended by that certain First Amendment to Crowfoot Development, LLC Limited Liability Company Agreement, entered into November 5, 2008, the " LLC Agreement" ), among the Company and the Members of the Company signatory hereto. This Amendment shall be effective as of March 1, 2009. Capitalized terms used and not otherwise defined in this Amendment will have the meanings set forth in the LLC Agreement.

RECITALS WHEREAS, the Members and the Company have heretofore entered into the LLC Agreement; and WHEREAS, the Members and the Company desire to amend the LLC Agreement in accordance with Section 16.6 thereof as provided herein. AGREEMENT

NOW, THEREFORE, in consideration of the premises and the mutual agreements herein contained, and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the Members hereby agree as follows: 1. Amendments . The LLC Agreement is hereby amended as follows: (a) Each reference to " Crowfoot Development, LLC" in the LLC Agreement, including, without limitation, Section 1.2, is deleted and replaced with " ADA Carbon Solutions, LLC."

(b) Section 3.2 is deleted in its entirety and replaced with the following:

3.2 Capital Contributions Generally . At such times as the Company requires Capital to meet the Capital Requirements of the Company, as reasonably determined by any Manager of the Company, the Company shall send to the Members a written notice (a " Capital Request Notice" ) advising the Members of such Capital requirements and specifying the individual Capital Contribution amount of each Member not less than 20 Business Days prior to the date on which the Capital Contributions are to be made (the " Required Funding Date" ). The ECP Members shall have the right to amend, modify and/or withdraw any or all of the terms of such Capital Request Notice in their sole discretion at any time on or prior to the tenth Business Day following delivery of such Capital Request Notice in accordance with Section 16.2 to the ECP Members. Any Capital Request Notice (including any Capital Request Notice amended or modified in accordance with the immediately preceding sentence) will be directed to Members in a manner consistent with such Members'

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