According to a source familiar with the probe , the grand jury investigation has been under way since just after the spill at the Freedom Industries chemical storage facility on the Elk River in Charleston . Tests find trace levels of contaminant remain in West Virginia water . Federal grand jury investigated chemical spill . The July 9 leak prompted a do - not - use order for up to 300,000 people . The chemicals leaked into the Elk River from a storage tank near the treatment facility .
Tests find trace levels of contaminant remain in West Virginia water . Federal grand jury investigated chemical spill . The July 9 leak prompted a do - not - use order for up to 300,000 people . The chemicals leaked into the Elk River from a storage tank near the treatment facility .