PacifiCorp Awards Contract to Construct Second Energy Gateway Transmission Expansion Project

February 14, 2011

100 mile high-voltage line from Mona to Oquirrh will benefit utility's customers and regional system

SALT LAKE CITY, Feb, 14, 2011 /PRNewswire via COMTEX/ --

PacifiCorp today announced it has awarded a multi-year contract to build its Mona-Oquirrh transmission line in Utah, a key section of PacifiCorp's regional investment program to meet the current and projected needs of its electric customers.

The contract has been awarded to EC Source, a MasTec, Inc. (NYSE: MTZ)affiliate. EC Source will provide engineering, procurement and construction services for this major transmission project, which will deliver additional power to serve customers of PacifiCorp's retail operating companies, Rocky Mountain Power and Pacific Power. Together, these companies serve more than 1.7 million customers in six western states.

"This segment, and our overall Energy Gateway transmission investment, is a fundamental part of PacifiCorp's plans and the region's plans to ensure long-term supply of reliable and affordable energy to meet the growing needs of our existing and future customers," said John Cupparo, vice president, transmission, PacifiCorp.

The Mona-Oquirrh segment is approximately 100 miles in length, consisting of a new single circuit 500/345-kilovolt transmission line from an existing substation in Juab County to a future Limber substation to be built in Tooele County, and a double-circuit 345-kilovolt line from Limber to the existing Oquirrh substation in West Jordan, Utah.

"We're pleased to begin construction of this important addition to the transmission system we all depend on," said Richard Walje, president of Rocky Mountain Power. "We look forward to completing it on time and within budget to provide the safe, reliable electric service that is essential to the economies of all the states we serve. We appreciate the efforts of federal agencies and county and city officials in working through the many extensive details of this project."

During construction, EC Source will have multiple project facilities along the transmission line route with its main facility near Tooele, Utah, and will utilize extensively the local Utah labor force. Construction is scheduled to begin this summer, and the Mona-Oquirrh segment is expected to be in service for customers by mid-year 2013.

"All members of the project team are focused on delivering technical excellence and industry-leading resources to another successful major transmission project for our industry," said Martin Maslonka, founding principal of EC Source. "The team's dedication to safety and environmental stewardship, demanded by the significant scale of the Mona-Oquirrh segment, will achieve optimal results for the Energy Gateway program and PacifiCorp's customers."

About Energy Gateway

In May 2007, PacifiCorp launched Energy Gateway, a significant transmission expansion investment program that will add approximately 2,000 miles of new transmission lines across the West. Siting and permitting processes now are underway for many segments of the planned expansion, and major segments of the multi-billion dollar project are scheduled to come on-line by 2014. One segment - the 135-mile Populus to Terminal line between Idaho and Utah - is already completed and on line, serving customers. More information can be found at www.pacificorp.com/energygateway.

About PacifiCorp

PacifiCorp operates as Rocky Mountain Power in Utah, Wyoming and Idaho and as Pacific Power in Oregon, Washington and California. PacifiCorp is one of the lowest-cost electricity producers in the United States, serving the energy needs of more than 1.7 million customers. The company works to meet growing energy demand while protecting and enhancing the environment. PacifiCorp has a net generation capacity of 10,607 megawatts from coal, hydro, gas-fired combustion turbines and renewable wind and geothermal power, and owns and operates 16,200 miles of transmission lines across the West.

About EC Source

EC Source, an affiliate of MasTec, Inc. (NYSE: MTZ), is a nationally recognized full-service EPC program management entity focused on deploying extra high voltage electrical systems in North America. ECS is staffed with recognized industry leaders in project planning and execution of large-scale electric transmission projects, including full service environmental planning, engineering, procurement and construction. ECS has completed major transmission projects for Arizona Public Service and American Electric Power, and is currently constructing a transmission project for Electric Transmission Texas as part of the Texas CREZ transmission build-out program.

SOURCE MasTec, Inc.