Calgary, December 15, 2004 (TSX – COS.UN) —Canadian Oil Sands Trust (the “Trust” or “Canadian Oil Sands”) advises that there was an electrical power interruption in Syncrude’s owned utilities which resulted in a temporary shut down of several units.  While the investigation as to the impact and cause of the power failure continues, it appears that only the LC Finer, an upgrading unit at Syncrude’s oil sands facility, will need to be shut down for approximately three weeks for the reloading of catalyst and the startup sequence resulting from the circulation loss caused by the sudden shutdown. 

In its current guidance for 2004, the Trust had budgeted for some unscheduled maintenance in its production estimate, which now has materialized.  Accordingly, the Trust’s 2004 production outlook remains at 87 million barrels for Syncrude, or 31 million barrels net to the Trust, with slightly higher operating costs.    Year to date shipments of Syncrude Sweet Blend (SSB) as at November 30, 2004 were 80.5 million barrels.  

Canadian Oil Sands provides monthly updates on production volumes and outlook on the Trust’s Web site at www.cos-trust.com under “the Syncrude Asset”, “SSB Production”. This press release is to remind investors and the media to consult the Web site in the future for information of this nature.

 Canadian Oil Sands Trust is an open-ended investment trust that generates income from its indirect 35.49 per cent working interest in the Syncrude Joint Venture. The Trust currently has approximately 91.4 million units outstanding, which trade on the Toronto Stock Exchange under the symbol COS.UN. The Trust is managed by Canadian Oil Sands Limited.

 
Advisory: in the interest of providing Canadian Oil Sands Trust (“Canadian Oil Sands” or the “Trust”) unitholders and potential investors with information regarding the Trust, including management’s assessment of the Trust’s future plans and operations, certain statements throughout this release contain “forward-looking statements” under applicable securities law.  Forward-looking statements in this release include, but are not limited to, statements with respect to: the expected production and operating costs for 2004. You are cautioned not to place undue reliance on forward-looking statements, as there can be no assurance that the plans, intentions or expectations upon which they are based will occur.  By their nature, forward-looking statements involve numerous assumptions, known and unknown risks and uncertainties, both general and specific, that contribute to the possibility that the predictions, forecasts, projections and other forward-looking statements will not occur.  Although the Trust believes that the expectations represented by such forward-looking statements are reasonable, there can be no assurance that such expectations will prove to be correct.  Some of the risks and other factors which could cause results to differ materially from those expressed in the forward-looking statements contained in this release include, but are not limited to: labour productivity; general economic, business and market conditions; commodity prices; and such other risks and uncertainties described from time to time in the reports and filings made with securities regulatory authorities by the Trust. You are cautioned that the foregoing list of important factors is not exhaustive.  Furthermore, the forward-looking statements contained in this release are made as of the date of this release, and the Trust does not undertake any obligation to update publicly or to revise any of the included forward-looking statements, whether as a result of new information, future events or otherwise.  The forward-looking statements contained in this release are expressly qualified by this cautionary statement.

-30-