ATCO Power already operates a gas fired power station in the region.

Bord Gáis and Canadian multinational ATCO Power withdrew from the project late last year.

Atco Chief Financial Officer Brian Bale said he did not expect any regulatory snags.

Atco affiliate Canadian Utilities CU.TO will operate the assets.

Corporate & Other segment includes ATCO Energy, a retail electricity and natural gas business in Alberta.

ATCO said the unnamed client was considering whether to go ahead with a planned mining project.

About ATCO Ltd. Atco Ltd is a Canada-based company, which offers infrastructure solutions to customers around the world.

The Atco group operates utilities, structures and logistics businesses and its energy segments include coal- and gas-fired power plants and distribution networks.

Atco said in a statement overnight it was in exclusive negotiations with AET&D Holdings and any deal was subject to board and regulatory approvals.

Atco Ltd ACOx.TO was awarded a contract for worker accommodations, while privately held German company Voith Hydro won a contract for turbines and generators.

Australian utility firm Duet Group, which owns equity interests in the assets up for sale, confirmed on Thursday it was in talks with Atco.

Atco shares fell 6 Canadian cents to close at C$62.40 on the Toronto Stock Exchange on Thursday.

It will eventually house 3,500 people, making it one of Atco Structures' largest such projects, division president Michael Shaw said.

Canadian Utilities, which is more than 82 percent owned by Atco, closed at C$55.75, down 15 Canadian cents.

Atco said its structures division will build a 600 person housing and core facility complex at the $3.8 billion mine.

Under the deal, expected to close in the third quarter, Atco will buy a 74.1 percent interest in WAGN from WestNet Infrastructure.