Florida’s Senate passed a measure on Wednesday that would relax environmental rules and allow untreated, partly contaminated water to be pumped into the state’s underground aquifers. Florida Gov. Jeb Bush (R) has asked the U.S. EPA for a waiver from the Safe Drinking Water Act, which requires any water pumped into the ground to be treated first to meet drinking-water standards. State officials say they need to move ahead with the plan because the aquifers, the state’s main source of fresh water, are already dangerously low. They say the bacteria in the tainted water could not survive underground or would not spread through groundwater. But opponents say pumping the water could put the state’s water supply at grave risk.