The Environmental Quality Commission shall establish a goal to reduce excess lifetime risk of cancer due to exposure to diesel engine emissions to no more than one case per million individuals by 2017. In setting the goal, the commission shall include a target to substantially reduce the risk to school children from diesel engine emissions produced by Oregon school buses by the end of 2013. The Department of Environmental Quality is directed to track and report to the Legislative Assembly on the progress in meeting this goal. [2007 c.855 § 2]