The Globe and Mail reports in its Saturday edition that Ontario Hydro approved the Darlington Nuclear Generating Station in Clarington, Ont., in 1977. The Globe's Matthew McClearn writes that by completion in 1993, its cost had ballooned to $14.5-billion, nearly double initial estimates. Darlington supplies one-fifth of Ontario's electricity, and it is in the midst of a $12.8-billion refurbishment, now more than half complete. The work involves replacing crucial components such as pressure tubes, which have reached the end of their service lives, so that the station can remain in service for another 30 years. Although considerably less risky than building new reactors, refurbishment is nonetheless an enormously complex undertaking. Long timelines expose projects to unlikely but consequential events such as financial crises or pandemics, as well as ever-shifting political winds. "On this reactor [Unit 3 of 4), we finished the full dismantling of the core," said Justin Alizadeh, head of the Canatom Power Group, a joint venture between SNC and Aecon Construction. "We're in this month-and-a-half phase right now of checking all of the parts of the reactor we're going to reuse, before we start installing new components."