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* March WCS trades at $21.00/bbl below WTI
* March synthetic trades at $1.50/bbl below WTI
CALGARY, Alberta, Feb 5 (Reuters) - Canadian cash crudeprices fell on Wednesday, with some traders saying recent gainshad gone too far given the looming refinery maintenance seasonthat will likely crimp demand.
Western Canada Select heavy blend for March delivery lasttraded at $21.00 per barrel below the West Texas Intermediatebenchmark, according to Shorcan Energy brokers.
That compares with a settlement price on Tuesday of $19.35per barrel below the benchmark, and marked a drop from Monday'ssix-month high settlement of $18.05 per barrel below thebenchmark.
"Going into turnaround (season), it's often weaker at thistime of year," said one Calgary crude trader, who also notedheavy crude prices were much stronger than this time in 2013when they traded around $30 per barrel below WTI.
Analysts have in part attributed more resilient prices thisyear to a relatively light maintenance turnaround schedule,which will get underway towards the end of this month.
Despite the maintenance, demand is likely to remain healthywith BP Plc's 405,000 barrel per day Whiting, Indiana,refinery switching over to processing more heavy Canadian crude.
Citgo Petroleum Corp also said the vacuum distillation unitat its 174,500 bpd Lemont, Illinois, refinery was restarted onTuesday and was at full production capacity after being shutsince an Oct. 23 fire.
Light synthetic crude from the oil sands for March deliveryalso fell to $1.50 per barrel below WTI, compared with asettlement price on Tuesday of 25 cents below the benchmark.
