Fram and Jason Chenier died in 2011 at Vale's Stobie Mine in Sudbury, Ontario.
The union, Steelworkers Local 6500, is trying to build momentum for safety probes after earlier refusals by the Ontario government to conduct an inquiry of the Fram and Chenier deaths.
The Fram family participate in the work of the Mining Inquiry Needs Everyone's Support (MINES) committee, who also seek prince-wide safety probes.
“There hasn't been a review of mining safety for many years, and that needs to happen,” Wynne said.
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