Mediation shall terminate:
- (a) At any time the Federal and State agencies agree to a resolution of the serious disagreement,
- (b) If one of the agencies withdraws from mediation,
- (c) In the event the agencies fail to reach a resolution of the disagreement within 15 days following Secretarial conference efforts, and the agencies do not agree to extend mediation beyond that period, or
- (d) For other good cause.