Less than two weeks after Alberta enacted legally enforceable pollution limits for its oilsands region, industry figures already suggest they will soon be breached by emissions of two major gases causing acid rain.

Regulatory documents for Shell's proposed Jackpine mine expansion say annual levels of sulphur dioxide and nitrogen dioxide will push past limits contained in the province's Lower Athabasca Regional Plan if all currently planned developments proceed.

'It's the first real test of the [plan].'—Simon Dyer, Pembina Institute

The documents, filed late last week, also provide what may be the clearest picture yet of what impact two decades of development have had on northeastern Alberta.

"It validates the concern that many stakeholders have raised about the cumulative pace and scale of development," said Simon Dyer of the Pembina Institute. "It's the first real test of the [plan]."

Shell filed the papers after the Canadian Environmental Assessment Agency asked the company to give a clearer account of how the environment of the oilsands region has changed since development began and what part the Jackpine expansion would play.

Written by environmental consultants Golder Associates, the document estimates how levels of the two gases have grown over the years.

Acid rain gases exceed 'trigger' levels

Average annual levels of sulphur dioxide are now about 20 times what they would naturally be over a large area from Fort McMurray to about 100 kilometres north.

Nitrogen dioxide is at least 10 times pre-development levels — although the report acknowledges hard data from that time is spotty.

The report finds that both gases already exceed "trigger" levels at which some form of regulatory action is supposed to kick in under the government's plan.

And if all the projects that have been announced publicly or are in the regulatory process go ahead, the pollutants are projected to exceed what are supposed to be absolute caps.

Sulphur dioxide will reach average annual concentrations of 21.1 micrograms per cubic metre of air, just over the plan's limit of 20 micrograms.

Nitrogen dioxide will reach 59.5 micrograms, well over the limit of 45.

The government is obliged to act if pollutants exceed either the "trigger" levels or the absolute caps — an obligation that Environment Minister Diana McQueen has underlined.

"It is a legally binding commitment that holds government accountable to Albertans," she said when announcing the plan Aug. 22.

Levels highest closest to mines

Spokespersons for the Alberta government or Shell weren't available for comment.

In the document, Shell points out the sulphur dioxide levels are concentrated in areas closest to its mines, regions that should be treated differently.

Levels in "non-developed areas" remain below the government's cap, it says.

It also says elevated nitrogen dioxide levels are a result of "over-predicted" emissions from giant trucks used in the mines and suggests those emissions are being reduced as the vehicles are upgraded.

Dyer says the government's plan makes no provision for treating some areas differently than others.

He also says contaminants in one area do ultimately spread throughout the region.

An earlier Shell document acknowledges 23 small, mostly unnamed lakes, have already passed their critical load for acid.

The document also lists cumulative effects that aren't yet governed by the regional plan, such as wildlife impacts.

Out of 22 indicator species — including birds, mammals and amphibians — 16 will suffer high or moderate negative consequences even under the current amount of development, it says.

Some areas will suffer "moderate" biodiversity loss, even after reclamation efforts.

Shell argues species will rebound as the area is returned to a more natural state and adds there should be enough undisturbed regions to maintain a healthy ecosystem.