First Nations and environmentalists say they are angry the federal and British Columbia governments continue to stonewall American requests for a joint investigation of cross-border contamination from coal mining as meetings of the panel that mediates such issues wrap up. "They can sit on every fence they want, but at the end of the day, we're going to do what's right," said Heidi Gravelle, chief of the Tobacco Plains First Nation, one of several bands upset over selenium contamination in southeastern B.C.'s Elk Valley from coal mines.