Edmonton Journal

Inquiry into steam use demanded

Environmen­talists call for study of oilsands extraction method

- LAUREN KRUGEL

CALGARY — More than 20 groups are calling for a public inquiry into the safety of oilsands extraction techniques that use steam.

The organizati­ons made their demand to the Alberta Energy Regulator on Tuesday as bitumen continues to ooze out of the ground at a project owned by Canadian Natural Resources Ltd.

The groups say CNRL’s Primrose East project, 250 kilometres northeast of Edmonton, isn’t the first example of an unexplaine­d failure of an oilsands operation like Primrose.

“It is time for a broader discussion of the safety and regulation of steam injection given these recurring events,” said Greenpeace campaigner Mike Hudema in a news release.

“The AER needs to reassure the Alberta public and other stakeholde­rs that it has the regulation­s in place to prevent similar incidents from occurring in the future.”

About half of current oilsands production comes from in-situ methods that pump steam deep undergroun­d to soften the tarry bitumen and enable it to flow through to the surface. The rest comes from open-pit mining of the oilsands.

The depth of the oilsands deposit is one of the factors that determines which method is used, but the trend has been toward more in-situ extraction methods.

The in-situ method will eventually account for about 80 per cent of the oilsands extraction­s, said Carolyn Campbell, of the Alberta Wilderness Associatio­n.

“Therefore, it’s important that we get this right,” Campbell said in the groups’ statement.

To extract bitumen at Primrose, CNRL uses a method called high pressure cyclic steam stimulatio­n, sometimes described as “huff and puff.” It involves injecting steam into a reservoir through a well, letting it soak for awhile and then drawing the softened bitumen to the surface through the same well.

The extraction method, which companies have used for decades, involves fracturing the rock to let the steam through, but not so much that it allows bitumen to flow to the surface.

A more common technique is steam-assisted gravity drainage, or SAGD, which pumps steam into one well and uses another well below it to bring the bitumen to the surface.

Though cyclic steam stimulatio­n has grabbed the most headlines recently, the environmen­tal coalition wants the Alberta Energy Regulator to examine both techniques.

CNRL says faulty old well bores are to blame for the Primrose East leak, though the AER says it still doesn’t know the cause.

An investigat­ion by Alberta’s energy watchdog into a similar 2009 leak at Primrose said a potential cause could have been “geologic weaknesses in combinatio­n stresses induced by high-pressure steam injection.”

But CNRL has said it’s unlikely damaged caprock was behind that spill and the more recent one, which was first detected in late June, about the time heavy rains caused severe flooding further south.

The damage at Primrose East has been contained to a 13.5-hectare area and the company has been cleaning up an estimated 20 barrels — nearly 3,200 litres — that continues to seep out every day at everdeclin­ing rates.

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