Two City of Burlington Summer Students were taken to hospital in critical head injuries after they were hit by an SUV while on the job. Halton Regional Police say the 19 and 22 year old male workers are now in stable condition. Their 34 year old female supervisor was also struck and taken to hospital but has since been released.It happened around 9:30am Thursday on a centre island median on Walkers Line south of Berton Avenue. The employees were doing landscaping work when the driver of a Nissan Pathfinder lost control and mounted the curb. The 51 year old male driver was not hurt. Police are still investigating the cause of the crash but have ruled out alcohol and cell phone use as possible factors. Anyone with information is asked to call Detective Constable Greg Cormier at 905-825-4747 ext. 5066.