CN says repairs have started on the collapsed rail bridge east of Fort Frances.
Damage to the lift bridge continues to prevent the movement of trains between Fort Frances and Thunder Bay.
It also restricts the movement of large vessels between the north and south ends of Rainy Lake.
In an email to Acadia News, CN says environmental crews did contain and have started to recover biodegradable, non-toxic hydraulic oil from the bridge.
It adds the bridge will remain closed until further notice.
CN offers no timetable as to when the bridge may be operational again.
The bridge collapsed Wednesday afternoon.
Much of the twisted metal lies on the tracks at the west end of the bridge.
Some of the tracks were also damaged.
The cause of the collapse has not been identified.