In this subtitle the following words have the meanings indicated. “Maximum contaminant level” means a standard that is: Set by the U.S. Environmental Protection Agency or the Department for drinking water quality; and The legal threshold limit on the amount of a substance that is allowed in a public water system under the federal Safe Drinking Water Act. “Private well” means a private or domestic water supply well that is a source of potable water. “Water quality testing” means water quality sampling, testing, and analysis: Conducted by a State–approved water sampler and a State–approved laboratory for a private well; and Of which the minimum sampling criteria include bacteria, nitrate, and turbidity. “Water quality testing” includes water quality sampling of any contaminant of concern, as determined by the Department.