"Fort Hall town site residents were advised to use bottled water through the holiday weekend, following the discovery of elevated levels of the pesticide ethylene dibromide in drinking water. Officials say an existing plume of the insecticide periodically breaches a filter maintained by the Fort Hall Water and Sewer District. A replacement carbon for the filter was expected to arrive July 3. "Every 12 to 15 months they have a breakthrough, and people get exposed," said Lisa DeJongh, Shoshone-Bannock water quality manager. The toxin has been linked to liver, kidney, nervous system and testicular disease and is a suspected carcinogen. DeJongh has been working to build a water delivery system here for several years. The Bureau of Reclamation will release a comprehensive feasibility study for a full water system to cover 140 miles on the reservation. Meanwhile, Fort Hall resident Ron Edmo is leading a campaign against the district, alleging years of neglect. Paul Murphy, the district's chairman, denied the agency has been negligent. "Right now all we're trying to do is provide clean water," he said. Residents will decide in August whether to nullify the Fort Hall Water and Sewer District.