Most everyone knows the U.S. imports a large percentage of the oil we use each day. As recently as three decades ago, about 28% of our oil came from other countries, while today that number has climbed closer to 60%. About 200 million barrels of black gold annually come from our neighbor to the north, Canada, which has surpassed Saudi Arabia as our largest supplier.

Further, more than half of the Canadian oil coming into the U.S. originates from oil sands in Alberta. Oil sands are a mixture of a nearly solid form of crude oil called bitumen, along with silica sand, clay, and water. A joint venture called Syncrude constitutes the world's largest producer of synthetic crude. Its participants include Imperial Oil (AMEX: IMO), Suncor (NYSE: SU), Nexen (NYSE: NXY), and Murphy Oil (NYSE: MUR).

Environmentalists claim the crude from oil sands is more carbon-intensive than other forms of oil. However, a Canadian federal panel reported this week that data from oil sands production -- which are gathered by industry, academia, and government -- are insufficiently dependable to provide a realistic handle on how much more environmentally damaging oil sands crude is than conventional oil.

The panel was formed following a study by University of Alberta scientist David Schindler, who maintains that byproducts from oil sands production are contaminating Alberta's Athabasca River. The newly issued report calls for a single data collection source. Two other reports issued by the Canadian federal environment commission and the Royal Society of Canada -- an independent group of scientists -- also advocate more adequate data monitoring in Alberta.

Following the issuance of the latest report, Alberta Environment Minister Rob Renner has agreed to form a group of experts to study the feasibility of a single data-collection system. At the same time, U.S. environmentalists are seeking to block the construction of a new oil pipeline proposed by TransCanada Corp. (NYSE: TRP). The line would transport oil from Alberta to the Gulf of Mexico and boost U.S. imports from Canada by a third. A decision on the project by the Obama administration is expected early in 2011.

Meanwhile, the Canadian Association of Petroleum Producers, whose board is chaired by Chris Seasons, president of Devon's (NYSE: DVN) Canadian unit, is unopposed to the establishment of a more efficient data gathering system.

So, with Canada's importance in providing oil to the U.S. growing, and with oil prices creeping higher, my belief in the compelling nature of shares in oil-sands-related companies continues to strengthen.    

TransCanada is a Motley Fool Global Gains recommendation. The Fool owns shares of Devon Energy. Try any of our Foolish newsletter services free for 30 days.

We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Fool contributor David Lee Smith doesn't own shares in any of the companies named in this article. The Motley Fool has a disclosure policy.