Wildrose party critic Jason Hale says the money is at risk because the project has already hit cost overruns and delays at a time when other refinery developments are being mothballed.
On Friday, Premier Alison Redford's cabinet agreed to put up $1 billion in provincially backed loans or other guarantees for the $8.5-billion North West Redwater refinery project near Edmonton.
Last month, the project announced a $2-billion cost overrun and its opening date was pushed back to the fall of 2017.
Hale says North West Upgrading Inc. has donated more than $36,000 to Redford's Progressive Conservative party since 2008.
He says he worries cabinet signed off on the $1-billion loan to appease a donor, but in doing so has risked millions of dollars in potential losses to taxpayers.
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