There are many forms of treatment technology, both new and old, that utilities use to treat water. Many are the same technologies that bottled water companies use for their products. Each contaminant, when regulated, has a Best Available Technology or BAT, determined for its removal, when necessary. The quality of the source water dictates what form of treatment, if any, is required. The types of BATs used for different contaminants are listed below. More specific information can be obtained on the DOHS or EPA web pages.