Canadian National Railway faces one charge under Alberta's environmental protection act in connection with a train derailment at Lake Wabamun last summer.

Alberta Environment has charged the company with failing to take all reasonable measures to remedy and confine a spill, an offence punishable by a maximum penalty of $500,000.

On Aug. 3, 2005, 43 cars of a CN freight train derailed and spilled 730,000 litres of oil and other chemicals into the lake, which is located about 50 kilometres west of Edmonton.

After the incident, health officials issued a water use advisory that banned swimming, fishing and the use of boats on the lake.

CN said Monday that major cleanup activities are expected to be complete by the end of June. The railway said crews will be available through the summer to deal with any oil that appears on the shoreline of Wabamun Lake.

"As this matter is now before the courts, CN will have no further comment at this time," the company said in a release.

In late May, health officials told area residents they can use the lake again, with some restrictions. The officials saidthe lake is safe for swimming and boating, but they advised people not to use the water for washing dishes, watering vegetables or showering.