The company and directors Shay Ben-Moshe and Valery Belahov were found guilty in June 2013 of a total of nine provincial offences related to the fiery 2008 blast that forced thousands from their homes and resulted in the deaths of two people.
The court ruled Sunrise failed to provide safety training and a safe working environment, discharged a contaminant and contravened a number of directives in a provincial order related to the cleanup after the blast.
The court also found that Ben-Moshe and Belahov failed to take all reasonable care to prevent the company from flouting those directives.
The company was cleared, however, of one count of failing to comply with a directive which involved notifying the Environment Ministry if it couldn't or was unable to clean up after the blast.
At a sentencing hearing for the company and its two directors, defence lawyer Leo Adler argued that given that finding, Justice Leslie Chapin should revisit six related offences in the case — one each against Ben-Moshe and Belahov, and four against Sunrise.
"Your Honour found that they had given the requisite notice that they were not going to comply with the order. That requisite notice having been found, the other subsections within the order are subsumed within that," he said.
Adler suggested that Chapin could either enter acquittals on those counts, or declare a mistrial on those offences.
Crown prosecutors argued there was no basis for the case to be reopened and said Adler was "simply trying to take another kick at the can."
From their perspective, Adler had not shown that there were any "exceptional circumstances" to warrant revisiting the convictions.
Twenty-five-year-old employee Parminder Saini died in the blast and a 55-year-old firefighter who responded to the emergency on his day off died of a heart attack.
Crown prosecutors are seeking millions of dollars in fines from Sunrise, and $100,000 in fines from each of the two directors.
Adler's arguments to revisit the convictions in the case centred around an order issued to the company by an officer from Ontario's Ministry of the Environment and Climate Change.
That order listed several requirements related to the ministry's expectations for the cleanup of debris and waste that had been scattered as a result of the explosion, as well as the cleanup of the blast site itself.
One of the directives in that order was that Sunrise needed to notify the officer if they could not or were unwilling to continue to comply with the requirements of the order. The company was charged with failing to comply with that part of the order, but was found not guilty.
Consequently, Adler argued, the rest of the directives in the order, and the charges related to them, were affected.
"To continue the cleanup work is redundant because they gave notice that they are not going to continue with the order," he said. "The various directives only come into play if you're going to comply with the order."
Crown prosecutors argued, however, that there was no specific language in the order indicating that a notification of an inability to comply with the order would "subsume" all the other directives.
"My friend's interpretation of the order defies both logic and common sense," said Justin Jacob, a lawyer for Ontario's environment ministry.
"It's very clear that the order contains eight separate distinct requirements. There's no basis in law or on the circumstances of this case to reopen this conviction"
The trial heard that, according to the government, the initial blast took place when propane vapours ignited during a risky truck-to-truck propane transfer.
The explosion launched fireballs into the sky, filled the air with smoke, shattered windows and coated lawns in toxic asbestos.
Following the blast, the government shut down all three of Sunrise Propane’s facilities.