FORT MCMURRAY, Alta. — A man has died while working on a giant bulldozer in Alberta’s oilsands.The provincial government says the 37-year-old was doing maintenance work on the machine at a Suncor (TSX:SU) mine site near Fort McMurray.The government says a reservoir or sump pan fell on the worker’s head. The man, who worked for the North American Construction Group, was taken to hospital in Fort McMurray, where he died of his injuries.This is the fourth fatality at Suncor’s oil-sands site near Fort McMurray and the deadliest stretch for oil workers in Alberta since 2009, according to the Wall Street Journal.Edmonton-based North American Construction Group said in a statement that the man was an out-of-province employee, but did not release his name. “We are devastated by this news and deeply saddened by the terrible and unexpected lose of our co-worker and friend,” Martin Ferron, company president, said Monday.“We will do everything within our power to provide the support they need during this extremely difficult time.”Suncor told the Wall Street Journal that is was taking every step possible to ensure its oil-sands complex near Fort McMurray is safe. “Safety is absolutely the No. 1 priority, and it is feeling more critical now,” Suncor spokeswoman Kelli Stevens said Tuesday.Lauren Welsh with Alberta’s Occupational Health and Safety department said officers are at the site investigating the death.Three other workers have died at Suncor job sites this year. Most recently, Lorna Weafer was killed by a black bear while working at the company’s base camp. Co-workers tried to scare the animal off the instrument technician but were unsuccessful.In April, an electrician was fatally injured while working near some electrical panels. Tailings operator Jerry Cooper’s body was found submerged in a sand dump in January.