The government has said it cost $190 million to cancel the gas plant, which was halted in mid-construction just days before the Oct. 6 2011 election in a move the opposition parties called a Liberal seat saver program.
However, the Progressive Conservatives and New Democrats suspect the actual cost to taxpayers will be much higher than the government is admitting.
Premier Kathleen Wynne has admitted it was a political decision by the Liberals to cancel the Mississauga project, which was widely opposed by local residents.
Wynne has also asked McCarter to examine the Liberals' move in 2010 to cancel another gas plant in neighbouring Oakville, which the government says will cost taxpayers $40 million, but that report won't be ready for several months.
The legislature's justice committee continued hearings Tuesday into the gas plants, with former energy ministry officials facing questions about the hundreds of millions of dollars the government apparently offered the developers of the cancelled projects.
PC energy critic Vic Fedeli was fuming when Craig MacLennan, former chief of staff to then energy minister Brad Duguid, testified he couldn't recall offers in the hundreds of millions of dollars for the cancelled Oakville project.
"I know you told me you didn't know about the $1.4 billion number until I showed you the email, are you telling me again ... a settlement offer was put together and rejected of $712 million that you were not aware of," asked Fedeli.
"I believe that's my recollection sir," MacLennan said under repeated questioning.
"I'm afraid the coverup continues," a frustrated Fedeli fired back.
NDP energy critic Peter Tabuns said he was astounded that the minister of energy's office did not turn over any documents on the cancelled gas plants as requested by the committee.
"Did you all delete your emails so there was no paper trail," asked an exasperated Tabuns.
"The fact that no staff in the minister's office would have a single email that would be responsive makes no sense to me, particularly when everyone knew politically how explosive this was."
MacLennan testified it was his habit to regularly delete emails so he would have a "clean" inbox.
"I regret that I didn't have any responsive documents," he said.
The Tories also complained Tuesday that the government was spending $600 an hour for lawyers to prepare executives at the Ontario Power Authority to testify at the committee, and said there were another two lawyers' bills for the cancelled gas plants that totalled $1 million.
"What’s wrong with simply putting your hand on the bible, swearing an oath and then telling the truth when you’re asked a question," wondered Fedeli.
"Can’t you just tell the truth?"
Energy Minister Bob Chiarelli wouldn't comment on the Tories' allegations about the big legal bills because he was unaware of where they got the figures.
"The Opposition referred to some leaked document," he said.
"Until I see the document I can’t comment on it."
The opposition parties estimate the cost of cancelling the two gas plants and instead building new generating stations in the Sarnia and Kingston areas will top $1 billion.
One energy consultant who testified at the justice committee hearings into the cancelled gas plants estimated the cost for the Oakville plant alone would be about $638 million.