Just key intersections, as I've said, where traffic volume is high and the train crosses traffic lanes in an odd way. At 28 Avenue it cuts across multiple lanes at an angle, so gates are going to be needed there. At 82 Avenue it not only crosses a major east-west artery but does so while simultaneously changing sides from the centre of the traffic lanes to the west side of the road. And the line will cross traffic lanes from the centre to the north side along Stony Plain Road in Glenora (around 139 St).
The City made a HUGE mistake in not elevating the line at 82 Avenue, and that intersection is going to be a problem for years. But as usual the Transportation department and City Council went for an el cheapo approach as if they hadn't learned a thing from the Metro Line Kingsway/NAIT debacle. They saved by keeping the line at grade but we're already seeing accidents in the area and the train isn't even running regular operations. Seems to me crossing gates are a small price to pay after such a major screwup.