Alberta’s provincial government introduced legislation on Tuesday to cap annual greenhouse gas emissions from its tar sands/oil sands sector at 100 megatonnes—some 50% higher than today, and amounting to 19% of the country’s entire emission budget for 2030.

“Alberta got the oil out of the sand, we can now get the carbon out of the barrel,” Environment Minister Shannon Phillips said in tabling the legislation, promised a year ago, in Edmonton this week. If passed, the measure would make Alberta the first major oil-producing jurisdiction in the world to set a quantitative limit on its emissions.

It would nonetheless allow the industry’s emissions—and production—to grow by more than half from current levels. And provincial officials concede the province has yet to figure out how to enforce the limit.

“Alberta’s oil sands emit 66 megatonnes of GHGs, slightly more than the province of British Columbia,” the Globe and Mail reported, citing federal data. The bill’s proposed 100-MT cap, which provincial officials expect the industry to reach by 2030, is close to the 115 MT Ontario has targeted for its entire economy by that year. It would also account for nearly one-fifth of the 524 MT the federal government has set as a national emissions target for that year.

Alex Ferguson, vice-president of the Canadian Association of Petroleum Producers, called the cap “a stake in the ground that means we need to focus on this,” and insisted that his “membership is completely aligned” with its intent.

Simon Dyer, Alberta associate director for the Pembina Institute, who is among the government’s advisors on the tar sands/oil sands, suggested the new limit could spur improvements in cleaner production, a goal that has not much advanced in the last 10 years.