The figure was laid before the House of Commons defence committee this week as it considered a request by the Department of National Defence for a budget top-up.
Defence Minister Peter MacKay says the total operational estimate for the 950 soldier contingent, over four years, is expected to be $522 million by the time the mission comes to an end next year.
The figure, like all Defence estimates, represents the incremental cost — the amount of money the department spends over and above the routine expense of maintaining an army.
It pales in comparison to the projected $7.9 billion spent fighting Taliban militants in the southern province of Kandahar between 2006 and 2011.
The Canadian training mission, based in Kabul, is slated to end in March 2014 with the last of the troops and equipment out of the country by the following August.
But there has been an intense debate among NATO nations in Brussels about the size of the Afghan security force to be left behind.
The alliance's stated goal had been to train 352,000 soldiers and police by the time western troops withdrew in 2014, but at last year's summit in Chicago the figure being used was 280,000.
Last month, just prior to a meeting of NATO defence ministers in Brussels, the U.S. began insisting the strength should be 350,000 — a demand that's at odds with other war-weary nations eager to pack up and go home.
Sources at NATO said Thursday there is also consternation about how much each nation will be asked to pay after 2014 to fund Afghan forces. The current budget is $4 billion and most observers agree it will be substantially higher with the proposed increase.
Douglas Bland, a former military officer and chair of defence studies at Queen's University in Kingston, Ont., said the public will wonder what it got for the extra $500 million spent on training, especially if allies leave before the job is done.
"Western governments are not keen on fighting indeterminate wars," said Bland. "You say to your people, 'We fought all of that way and what you see is what you get.' And that's not victory."
In Canada, the message will be even harder to deliver.
Prior to the end of the Kandahar deployment, Prime Minister Stephen Harper had insisted that all troops would be out of Afghanistan and only a couple of guards would be left at the embassy in Kabul.
But that abruptly changed in November 2010 when Harper announced Canada would stay on in Kabul to give classroom instruction to Afghan forces.
NDP defence critic Jack Harris said it might turn out to be a huge waste of money, especially if ill-trained Afghan forces are unable to hold the country together after 2014.
"I'm not sure we got very much because our position was we should have ended the military mission and focused our attention on governance and civil society," Harris said.
He said his fear is that when NATO forces leave there's going to be a vacuum and Afghan society will be unable to sustain itself.
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