Aecon Group, Canada largest construction firm, announced Monday it has signed a letter of intent with the Potash Corporation of Saskatchewan for a project valued at over $250 million to install the interior of a new process mill at the PotashCorp mine site near Rocanville, Saskatchewan. The project will create approximately 800 jobs at the construction site said Aecon in a press statement.  Site preparation is expected to begin in early 2012 and this portion of the project is scheduled for completion in the fall of 2013. Monday's deal brings the total value of projects announced by Aecon since September to over $850 million which has given its share price in Toronto an almost 30% boost over the period.