Sixth Amended and Restated Rent Supplement (CREZ Lease) March 13, 2015

Exhibit 10.13

Sixth Amended and Restated Rent Supplement

(CREZ Lease)

March 13, 2015

This Sixth Amended and Restated Rent Supplement (this “Sixth Amended Supplement”) between Sharyland Projects, L.L.C. (“Lessor”) and Sharyland Utilities, L.P. (“Lessee”) is executed and delivered on March 13, 2015, to memorialize supplements to the CREZ Lease (as defined below), effective as of January 1, 2015. Capitalized terms used herein that are not otherwise defined will have the meanings assigned to them in the CREZ Lease.

WHEREAS, Lessor and Lessee are Parties to a Second Amended and Restated Lease Agreement (CREZ Assets) dated as of December 1, 2014 (the “CREZ Lease”);

WHEREAS, the Parties executed a Fifth Amended and Restated Rent Supplement (CREZ Lease) effective as of January 1, 2015 (the “Fifth Amended Supplement”);

WHEREAS, the Incremental CapEx and Lessee CapEx for 2014 were different than expected and the Parties wish to effect a Rent Validation (as set forth in Section 3.2(c) of the CREZ Lease) to memorialize the effect of such difference;

WHEREAS, as a result of this Rent Validation, a one-time payment set forth below is owed and will be paid promptly upon execution hereof; and

WHEREAS, the Parties wish to amend and restate the Fifth Amended Supplement pursuant to Section 3.2(c) of the CREZ Lease.

NOW THEREFORE, in consideration of the premises and for other good and valuable consideration, the receipt of which is hereby acknowledged, the Parties hereto agree to the following:

1. The Fifth Amended Supplement is hereby amended and restated in its entirety as set forth below.

2. The CREZ Lease, except as supplemented by this Sixth Amended Supplement, shall remain in full force and effect.

Validation Payment: As a result of the validation described above, pursuant to Section 3.2(c) of the CREZ Lease, Lessor will pay Lessee $404,208.00 promptly following execution hereof.

Termination date of this Rent Supplement: December 31, 2020.

The Parties have executed this Sixth Amended Supplement to the CREZ Lease as of the date set forth above.