Exhibit 10.59

EXECUTION VERSION

SITE WORK AGREEMEN T

between

R ED R IVER E NVIRONMENTAL P RODUCTS , LLC

Owner

and

BE&K C ONSTRUCTION C OMPANY , LLC

Contractor

January 23, 2009

List of Annexes

Page i

SITE WORK AGREEMENT

This SITE WORK AGREEMENT (this “ Site Work Agreement ”) is entered into as of the 23rd day of January, 2009, by and between Red River Environmental Products, LLC, a Delaware limited liability company (“ Owner ”), and BE&K Construction Company, LLC, a Delaware limited liability company (“ Contractor ”). Owner and Contractor are sometimes collectively referred to herein as the “ Parties. ” Capitalized terms used but not defined herein will have the meaning set forth in the Preliminary EPC Agreement (defined below).

W I T N E S S E T H :

WHEREAS, Owner is developing, constructing and intends to operate and maintain the Project located at the Project Site in order to produce activated carbon and electricity from the processing of lignite coal;

WHEREAS, Owner and Contractor are parties to an Engineering, Procurement and Construction Agreement dated as of January 29, 2008 (the “ Preliminary EPC Agreement ”) pursuant to which the Parties agreed upon the terms and conditions for providing certain preliminary engineering, design and long lead procurement activities and certain terms and conditions to be included in the Full EPC Agreement and this Site Work Agreement;

WHEREAS, the Parties entered into a Letter Agreement, dated as of August 15, 2008, as supplemented by a Supplemental Letter Agreement, dated as of August 25, 2008 (collectively, the “ Letter Agreement ”), providing for the performance of certain procurement services for the Project, to include procurement of certain site work and other related services;

WHEREAS, the Parties entered into an Amended and Restated Engineering, Procurement and Construction Agreement dated as of September 8, 2008 (the “ Full EPC Agreement ”) providing for the performance of certain engineering, design, procurement, construction, construction management, testing, commissioning and related services for the Project;

WHEREAS, pursuant to this Site Work Agreement, the Parties intend to amend the Preliminary EPC Agreement so as to provide for the performance of certain site work and other related services described in the Preliminary EPC Agreement, commenced pursuant to the Letter Agreement;

WHEREAS, the Parties desire for this Site Work Agreement to be the complementary amendment to the Preliminary EPC Agreement, such that the Full EPC Agreement and this Site Work Agreement reflect the complete agreement of the Parties and explicitly replace the Preliminary EPC Agreement and the Letter Agreement;

Page 1 of 5

NOW, THEREFORE, in consideration of the foregoing premises and the mutual covenants and agreements contained herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties covenant and agree as follows:

ARTICLE 1

GENERAL

1.1 Preliminary EPC Agreement . Unless specifically amended or excluded pursuant to the provisions below, the provisions of the Preliminary EPC Agreement relating to “Phase 1” shall be applicable to and govern the performance of the Site Work (defined below) under this Site Work Agreement.

1.2 Scope of Work . The Scope of Work to be performed pursuant to this Site Work Agreement shall be as set forth in Annex 1 (the “ Site Work ”).

1.3 Payment for the Site Work; Scheduling of the Site Work.

1.3.1 Payment . Payments for performance of the Site Work to be performed pursuant to this Site Work Agreement shall be made in the same manner as provided for payment of the Phase 1 Work under the Preliminary EPC Agreement, with the exceptions provided in Annex 2. Contractor covenants to use its commercially reasonable good faith efforts in a timely fashion during prosecution of the Site Work (i) to verify the performance of the Subcontractors under the Contractor Subcontracts listed in Annex 3, (ii) to reconcile the estimated costs provided in such Contractor Subcontracts with actual costs incurred pursuant to such Contractor Subcontracts and (iii) to anticipate any cost over