An oil spill that went undetected for days has released 22,000 barrels of oil into northeastern Alberta’s muskeg, news sources report.

The spill, an emulsion composed of oil and water, came from a waste disposal line owned by Pace Oil and Gas, and was evidently only discovered when an aircraft from another oil company made a routine flyover in the area on May 19, the Calgary Herald reports.

The spill is “among the largest in North America in recent years,” reports the Globe and Mail.

Pace Oil and Gas has set up a 50-person camp near the spill, which is located about 20 kilometres southwest of Rainbow Lake, in northern Alberta, the Globe reports. The company has built trenches around the site and oil-skimming equipment has so far recovered about 11 per cent of the emulsion, according to company spokespeople.

This is the second major oil spill in Alberta in a year. Last year, the Rainbow pipeline, owned by Plains All American Pipeline, spilled 28,000 barrels of oil into northern Alberta’s forests.

Also last year, Alberta-based Enbridge struggled with an oil leak from a pipeline in Michigan, after a two-vehicle collision damaged an above-ground portion of the pipe.

Regulators told the Herald that spills like the one at Rainbow Lake are infrequent, despite the large volume of oil that moves out of the province every day.

"These types of spills are rare," Darin Barter of Alberta's Energy Resources Conservation Board told the Herald.

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  • 10. Oil And Gas Accounts For 4.8 Per Cent Of GDP

    The oil and gas industries accounted for around $65 billion of economic activity in Canada annually in recent years, or slightly less than 5 per cent of GDP. Source: <a href="http://www.ceri.ca/docs/2010-10-05CERIOilandGasReport.pdf" target="_hplink">Canada Energy Research Institute</a>

  • 9. Oil Exports Have Grown Tenfold Since 1980

    Canada exported some 12,000 cubic metres of oil per day in 1980. By 2010, that number had grown to 112,000 cubic metres daily. Source: <a href="http://membernet.capp.ca/SHB/Sheet.asp?SectionID=9&SheetID=224" target="_hplink">Canadian Association of Petroleum Producers</a>

  • 8. Refining Didn't Grow At All As Exports Boomed

    Canada refined 300,000 cubic metres daily in 1980; in 2010, that number was slightly down, to 291,000, even though exports of oil had grown tenfold in that time. Source: <a href="http://membernet.capp.ca/SHB/Sheet.asp?SectionID=7&SheetID=104" target="_hplink">Canadian Association of Petroleum Producers</a>

  • 7. 97 Per Cent Of Oil Exports Go To The U.S.

    Despite talk by the federal government that it wants to open Asian markets to Canadian oil, the vast majority of exports still go to the United States -- 97 per cent as of 2009. Source: <a href="http://www.nrcan.gc.ca/statistics-facts/energy/895" target="_hplink">Natural Resources Canada</a>

  • 6. Canada Has World's 2nd-Largest Proven Oil Reserves

    Canada's proven reserves of 175 billion barrels of oil -- the vast majority of it trapped in the oil sands -- is the second-largest oil stash in the world, after Saudi Arabia's 267 billion. Source: <a href="http://www.ogj.com/index.html" target="_hplink">Oil & Gas Journal</a>

  • 5. Two-Thirds Of Oil Sands Bitumen Goes To U.S.

    One-third of Canada's oil sands bitumen stays in the country, and is refined into gasoline, heating oil and diesel. Source: <a href="http://www.nrcan.gc.ca/statistics-facts/energy/895" target="_hplink">Natural Resources Canada</a>

  • 4. Alberta Is Two-Thirds Of The Industry

    Despite its reputation as the undisputed centre of Canada's oil industry, Alberta accounts for only two-thirds of energy production. British Columbia and Saskatchewan are the second and third-largest producers. Source: <a href="http://www.nrcan.gc.ca/statistics-facts/energy/895" target="_hplink">Natural Resources Canada</a>

  • 3. Alberta Will Reap $1.2 Trillion From Oil Sands

    Alberta' government <a href="http://www.huffingtonpost.ca/2012/03/27/alberta-oil-sands-royalties-ceri_n_1382640.html" target="_hplink">will reap $1.2 trillion in royalties from the oil sands over the next 35 years</a>, according to the Canadian Energy Research Institute.

  • 2. Canadian Oil Consumption Has Stayed Flat

    Thanks to improvements in energy efficiency, and a weakening of the country's manufacturing base, oil consumption in Canada has had virtually no net change in 30 years. Consumption went from 287,000 cubic metres daily in 1980 to 260,000 cubic metres daily in 2010. Source: Source: <a href="http://membernet.capp.ca/SHB/Sheet.asp?SectionID=6&SheetID=99" target="_hplink">Canadian Association of Petroleum Producers</a>

  • 1. 250,000 Jobs.. Plus Many More?

    The National Energy Board says oil and gas employs 257,000 people in Canada, not including gas station employees. And the Canadian Association of Petroleum Producers says the oil sands alone <a href="http://www.capp.ca/aboutUs/mediaCentre/NewsReleases/Pages/OilsandsaCanadianjobcreator.aspx" target="_hplink">will grow from 75,000 jobs to 905,000 jobs by 2035</a> -- assuming, of course, the price of oil holds up.