(a) This part applies to chemical facilities and to covered facilities as set out herein; and

(b) This part does not apply to a facility that is excluded as set forth in 6 U.S.C. 621(4):

(1) A facility regulated under the Maritime Transportation Security Act of 2002 (Pub. L. 107-295; 116 Stat. 2064);

(2) A public water system, as that term is defined in 42 U.S.C. 300f;

(3) A Treatment Works, as that term is defined in 33 U.S.C. 1292;

(4) A facility owned or operated by the Department of Defense or the Department of Energy; or

(5) A facility subject to regulation by the Nuclear Regulatory Commission, or by a State that has entered into an agreement with the Nuclear Regulatory Commission under 42 U.S.C. 2021(b) to protect against unauthorized access of any material, activity, or structure licensed by the Nuclear Regulatory Commission.