Another possibility for future U.S. Natural Gas supplies lies in northern Canada, which contains around one third of that countrys recoverable gas reserves. The Mackenzie Valley Pipeline, for instance, could carry as much as 1.2 Bcf/d of gas from Canadas far north to southern Canada and the United States, possibly beginning in 2008 (assuming satisfactory completion of a regulatory and environmental review; currently, the project appears stalled). However, Canada is consuming increasing volumes of gas itself for such activities as Oil sands extraction and processing. Accordingly, Canada may export less natural gas to the United States than is now expected. A competing pipeline would transport natural gas from Alaskas North Slope to the lower-48 states, with possible capacity as high as 4-5 Bcf/d, potentially beginning sometime around 2012.