(a) The commission will specify in the facility permit the point of compliance at which the groundwater protection standard of §335.158 of this title (relating to Groundwater Protection Standard) applies and at which monitoring must be conducted. The point of compliance is a vertical surface located at the hydraulically downgradient limit of the waste management area that extends down into the uppermost aquifer underlying the regulated units.      
        (b) The waste management area is the limit projected in the horizontal plane of the area on which waste will be placed during the active life of a regulated unit.        
          (1) The waste management area includes horizontal space taken up by any liner, dike, or other barrier designed to contain waste in a regulated unit.          
            (2) If the facility contains more than one regulated unit, the waste management area may be described in the following manner:                          (A) by animaginary line circumscribing the several regulated units;                              (B) by an imaginary line circumscribing geographically proximate regulated units;                                  (C) by an imaginary line circumscribing individually regulated units; or                                      (D) a combination of subparagraphs (B) and (C) of this paragraph.                   
     Source Note:        The provisions of this §335.161 adopted to be effective May 28, 1986, 11 TexReg 2347.