PRINCE GEORGE, B.C. -- The man in charge of leak detection for the proposed Northern Gateway pipeline project says he's been under orders to build a world-class, industry-leading pipeline to deliver crude from Alberta to a tanker port on the B.C. coast.

Barry Callele, the director of pipeline control systems and leak detection at Enbridge (TSX:ENB) Inc., says the company is testing every spill detection technology available, and cost is no factor in ensuring the safety of the 1,100-kilometre twin lines proposed across the remote northern B.C. wilderness.

But while zero spills are the aim, Callele says leaks do happen.

Lawyers for the province of British Columbia are grilling Enbridge experts for the second day at environmental assessment hearings in Prince George.

Lawyer Chris Jones raised several questions about the pipeline's design and about spills along Enbridge pipelines in the Northwest Territories and in the Kalamazoo River in Michigan.

Callele says errors clearly occurred but many procedural and "cultural" changes have been put in place since the 2010 spill in Michigan.