Emmanuel Villalobos Forward Marketer, Long-Term Trading El Paso Electric Company September 17, 2014 Mr. Don Stoneberger Freeport-McMoRan Copper & Gold Energy Services

Exhibit 10.42-06

Xxxxxxxx Xxxxxxxxxx

Forward Marketer, Long-Term Trading

El Paso Electric Company

September 17, 2014

Xx. Xxx Xxxxxxxxxxx

Freeport-McMoRan Copper & Gold Energy Services

000 Xxxxx Xxxxxxx Xxxxxx Xxxxx 00.000

Xxxxxxx, XX 00000

Re: Power Purchase and Sale Agreement between Freeport-McMoRan Copper & Gold Energy Services, LLC And El Paso Electric Company

Dear Xx. Xxxxxxxxxxx,

Pursuant to Section 3.4 of the Power Purchase and Sale Agreement (“Agreement”) between Freeport-McMoRan Copper & Gold Energy Services, LLC (“FMES”) (formerly, Xxxxxx Dodge Energy Services, LLC) and El Paso Electric Company (“EPE”), FMES and EPE (collectively the “Parties”) hereby agree to maintain the quantity for energy to be purchased and sold under Sections 3.1 and 3.2 of the Agreement at 125 MW per hour through 11:59 p.m. Mountain Standard Time on December 31, 2015. This is in accordance with our recent phone conversations, and subsequent acceptance of FMES’ offer for an additional 25 MW for the period of one year. The parties further agree that the quantity of firm energy that may be dispatched by EPE pursuant to Section 3.6 of the Agreement is 125 MW per hour, less the quantity of energy sold and delivered by FMES pursuant to Section 3.1. The amount of energy to be purchased and sold under the Agreement was set to revert to the original base contract amount of 100 MW per hour, on 11:59 p.m. Mountain Standard Time on December 31, 2014, based on a May 13, 2013 agreement between the Parties.

Please indicate FMES’ acknowledgement of the foregoing agreement by signing this letter in the place indicated below and returning the original or a copy thereof to my attention at your earliest convenience.

Sincerely,

Xxxxxxxx Xxxxxxxxxx

/s/ Xxxxxxxx Xxxxxxxxxx

[AUTHORIZING SIGNATURES]

El Paso Electric Company

APPROVED AS TO FORM

OFFICE OF THE GENERAL COUNSEL /s/ Xxxxxxx Xxxxx

/s/ Xxxxx X. Xxxxxxx

VP System Operations Resource Planning & Management

Freeport-McMoRan Copper & Gold Energy Services, LLC

/s/ Don Stoneberger____________________

President, Freeport-McMoRan Copper & Gold Energy Services, LLC