Tests find trace levels of contaminant remain in West Virginia water . Federal grand jury investigates chemical spill . The January 9 leak prompted a do-not-use order for up to 300,000 people . The results by TestAmerica found the chemical is within the safe level of 1 part per million set by the Centers for Disease Control and Prevention ; whether that level is safe is disputed . Comment:
Tests find trace levels of contaminant remain in West Virginia water . Federal grand jury investigates chemical spill . The January 9 leak prompted a do-not-use order for up to 300,000 people . Comment: