The general duty under s17 to avoid, remedy or mitigate any adverse effects on the environment applies to any activity carried out by or on behalf of a requiring authority under a designation.  Section 322 provides for an enforcement officer to serve an abatement notice on persons who undertake unauthorised works on designated land.  Alternatively, under s316 any person may apply to the Environment Court for an enforcement order to be made against persons who are undertaking unauthorised works on designated land.