Kiewit/Aecon joint venture awarded $1.7 billion contract for Lower Mattagami
Hydroelectric Complex

- Aecon to hold 20% of construction joint venture -

TORONTO, June 7 /CNW/ - Aecon Group Inc. (TSX: ARE) announced today that its Infrastructure Division has partnered with Peter Kiewit Sons Co. for a $1.7 billion design build contract awarded by Ontario Power Generation for the construction of the Lower Mattagami Hydroelectric Complex, about 70 km northeast of Kapuskasing.

Under the agreement, Aecon holds a 20% interest in the construction joint venture that will redevelop four generating stations on the Mattagami River.

Completion of this project is expected in 2015.

"This is an important project and we are committed to working safely, and completing the work on time, and on budget, said Teri McKibbon, CEO of Aecon Infrastructure. "We are very pleased to be partnered with Kiewit, a company acknowledged as a world class leader in hydro development projects".

Aecon Group Inc. is Canada's largest, publicly traded construction and infrastructure development company. Aecon and its subsidiaries provide services to private and public sector clients throughout Canada and on a selected basis internationally. Aecon is pleased to be recognized as one of the 50 Best Employers in Canada as published by Report on Business Magazine.

Peter Kiewit Sons Co. is the Canadian construction arm of the Kiewit Construction Company (KCC), a diversified, employee owned contracting corporation operating throughout North America and internationally. KCC has been in business since 1884 and ranks among the largest and most successful construction companies in North America.

The information in this presentation includes certain forward-looking statements. These "forward-looking" statements are based on currently available competitive, financial and economic data and operating plans but are subject to risks and uncertainties. In addition to general global events outside Aecon's control, there are factors which could cause actual results, performance or achievements to vary from those expressed or inferred herein. Risk factors are discussed in greater detail in the section on "Risk Factors" in the Annual Information Form filed on March 31, 2010 and available at www.sedar.com. Forward-looking statements include information concerning possible or assumed future results of operations or financial position of Aecon, as well as statements preceded by, followed by, or that include the words "believes," "expects," "anticipates," "estimates," "projects," "intends," "should" or similar expressions. Important factors, in addition to those discussed in this document, could affect the future results of Aecon and could cause those results to differ materially from those expressed in any forward-looking statements.

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For further information: Mitch Patten, Senior Vice President, Corporate Affairs, Aecon Group Inc., [phone], [email protected], www.aecon.com