MATTAWA - An extensive effort to clean up more than 20,000 litres of spilled diesel fuel is underway in a remote area near Mattawa following a train derailment.

The Ottawa Valley Railway has deployed three environmental clean-up and water quality contractors to the area some 60 kilometres east of North Bay.

The crews have laid out an absorbent boom to contain any fuel remaining in the area, though most of the spill wound up in the Ottawa River.

Officials say drinking water taken from the river has not been affected. The diesel is not expected top advance past Rolphton.

The crews will direct that spilled fuel to shore and extract it at a site about eight kilometres east of the derailment.

The train went off the tracks early Wednesday when it encountered a washout caused by the collapse of three beaver dams.

The railway says so far, no effect on wildlife has been observed.

With a report from CTV Ottawa