By Nia Williams
CALGARY, Alberta, Aug 10 (Reuters) - Athabasca Oil Corp
ATH.TO has suspended the production of 4,200 barrels of oil
equivalent a day (boe/d) of light oil, becoming the latest
western Canadian producer to curb output due to the Alliance
Pipeline APLP.UP natural gas mainline shutdown.
Alliance declared force majeure on its 2,400-mile (3,850-
km) pipeline, which delivers gas and natural gas liquids from
western Canada and North Dakota's Williston Basin to the Chicago
market, last week after poisonous hydrogen sulphide entered the
system.
The pipeline company, a limited partnership owned by
affiliates of Enbridge Income Fund Holdings ENF.TO and Veresen
Inc VSN.TO , called on shippers to suspend injections into the
pipeline on Friday so the affected gas could be flared off.
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The Alliance mainline accounts for about a third of Canada's
daily net exports to the United States and the shutdown is
expected to last several more days.
Athabasca said on Monday it managed to shift a portion of
its production from the Kaybob region in west central Alberta to
other pipeline systems, but approximately 84 percent of its
light oil output was impacted nonetheless.
It joins a number of other oil and gas producers, including
Seven Generations Energy VII.TO and NuVista Energy Ltd
NVA.TO , that have been forced to trim some or all production.
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Athabasca said five days of downtime on the Alliance
pipeline would cut its third quarter light oil production
guidance of 5,000 boe/d by approximately 250 boe/d.
The hydrogen sulphide gas entered the pipeline system as a
result of complications experienced by an upstream operator that
Alliance did not name.
However, midstream company Keyera Corp KEY.TO said it had
a brief operational upset last Wednesday at its Simonette,
Alberta, gas plant, which resulted in gas that did not meet
sales gas specifications entering the Alliance Pipeline.
Keyera said it had offered assistance to Alliance and was
working with producer customers to divert their gas.
(Editing by Alan Crosby)