To absolutely no one’s surprise, Canada’s oil-sands operations have been given poor environmental marks in a study by green groups Pembina Institute and the World Wildlife Fund. Ten oil-sands ventures in the province of Alberta, including seven that have not yet started producing, were rated on their pollution of (or potential to pollute) the land, air, and water, as well as their greenhouse-gas emissions and overall environmental management. The top-ranked oil-sands project, Royal Dutch Shell’s Muskeg River mine, garnered a score of merely 56 percent; the average score was 33 percent. If each company adopted the best practices of its rivals, the impact would be significant, say the green groups — especially as Alberta’s oil-sands output is expected to triple within a decade.