* June WCS last seen at $24.25/bbl under WTI
* June synthetic at $0.80/bbl discount to WTI
CALGARY, Alberta May 6 Canadian oil prices fell on Monday as a result of planned and unplanned refinery maintenance and the prospect of abundant supply.
Western Canada Select heavy blend for June delivery last traded at $24.25 per barrel below the West Texas Intermediate benchmark, according to Shorcan Energy Brokers.
That compares with a settlement price on Friday of $21.65 per barrel under WTI.
Light synthetic crude from the oil sands last traded at a discount of $0.80 per barrel under WTI, down from a settlement price on Friday of $3.00 per barrel over the benchmark.
Suncor Energy Inc's 140,000 barrel per day refinery in Edmonton, Alberta, was in full shutdown.
The company had expected to continue producing gasoline during a planned maintenance turnaround but the discovery of corrosion in a line leading to a flare forced the closure of the gasoline unit for repairs.
A trader also cited planned maintenance at Flint Hill Resources' 320,000 bpd Pine Bend refinery in Minnesota and a major turnaround at Exxon Mobil Corp's 238,600 bpd plant in Joliet, Illinois, as factors weighing on demand.
Meanwhile, the market was bracing for the arrival of new heavy oil supplies in coming weeks.
Canadian Natural Resources Ltd said it expected new oil from its Pelican Lake and Wodenhouse fields to hit the market in June, while Imperial Oil Ltd started production at its Kearl oil sands project in eastern Alberta in late April.
Those Kearl supplies could take as long as three months to reach Canadian markets however, analysts have said, as Imperial must first fill storage tanks and a pipeline to the facility.