ecoRI: Massachusetts motorists will soon be filling their tanks with gas increasingly derived from Canadian tar sands oil, according to a new report from the Natural Resources Defense Council (NRDC). A flood of dirty fuel into Massachusetts would undercut the states efforts to reduce carbon pollution, according to the NRDC. The report found that under current plans, tar sands-derived gasoline supplies in 11 Northeast and Mid-Atlantic states would soar from less than 1 percent in 2012 to 11.5 percent of...