BC Hydro has selected its main contractor to construct the third dam on the Peace River, and is finalizing a $1.5 billion contract for a dam and river diversion that is the largest in the utility's history.

The three members of Peace River Hydro Partners are Korean engineering and electronics giant Samsung, Spanish dam and infrastructure specialist ACCIONA and Petrowest Corp., a Calgary-based company that has expanded from oil and gas construction to large infrastructure in northeast B.C. and Alberta.

Petrowest and ACCIONA worked on the recently completed Fort St. John hospital, and ACCIONA has built hydro dams in Spain and Chile. Samsung has built hydro dams, roads, buildings, tunnels, bridges and airports.

Energy Minister Bill Bennett said the contract will be for a fixed price to build the main "civil works," which include excavation, river diversion tunnels, intake and outlet structures, a kilometre-long earth-filled dam, a 70-metre-high concrete buttress and a road network.

Bennett said work can proceed in winter, and he is confident BC Hydro can stay within its estimated project cost of $8.3 billion.

When the decision to proceed was made a year ago, oil and gas activity was high and there were concerns about labour shortages. But with a continuing slump in oil, natural gas and mineral prices, there are idled workers and equipment in Fort McMurray and other sites in Western Canada.

"Mining is really slow right now and LNG has not yet taken off, so you actually have almost a perfect circumstance for BC Hydro to be entering into its major contracts on Site C," Bennett said.

Petrowest CEO Rick Quigley said the project will hire locally first, from around B.C. second and elsewhere in Canada third before looking outside the country for skilled labour.

BC Hydro also identified Peace River Hydro Partners' labour agreements with Christian Labour Association Canada and Construction Maintenance and Allied Workers' Canada, which broke away from the U.S. international carpenters' union in 2007.

B.C. Building Trades executive director Tom Sigurdson issued a statement protesting the choice.

"Premier Clark has long said that B.C. workers should be the first in line for Site C work," Sigurdson said. "This has not been the case so far under the first major contract, awarded to a large Alberta company which has one of four workers on site from out of province."