((a)) To the extent that any provision of this subchapter applies to any act or omission, no State or any political subdivision thereof may adopt or continue in effect, except as provided in subsection (b), any provision of law or regulation with respect to such act or omission, unless such provision of such law or regulation is the same as the applicable provision of this subchapter.
((b)) A State or political subdivision thereof may provide for any investigative or enforcement action, remedy, or penalty (including procedural actions necessary to carry out such investigative or enforcement actions, remedies, or penalties) with respect to any provision of law or regulation permitted by subsection (a).