New book - 'Building a Better World in Your Backyard' - on Kickstarter (sponsored friend)
Best Available Technology
Best Available Technology (BAT) is a system used for policies regarding regulations on the discharge of pollutants. It forces treatment plants to keep their equipment up to date so that the effluent is as clean as possible. It does not mean best available technology in a literal sense but more best technology that is economically feasible. In the US it is used primarily in the Clean Air Act and the Clean Water Act.