(1) Notwithstanding any other provision of this part, or rules promulgated under this part, the department shall allow for a mixing zone for discharges of venting groundwater in the same manner as the department provides for a mixing zone for point source discharges. Mixing zones for discharges of venting groundwater shall not be less protective of public health or the environment than the level of protection provided for mixing zones from point source discharges.

    (2) Notwithstanding any other provision of this part, if a discharge of venting groundwater is in compliance with the water quality standards provided for in this part and the rules promulgated under this part, a permit is not required under this part for the discharge if the discharge is provided for in either or both of the following:

    (a) A remedial action plan that is approved by the department under part 201.

    (b) A corrective action plan that is submitted to the department under part 213 that includes a mixing zone determination made by the department and that has been noticed in the department calendar.

    (3) As used in this section:

    (a) "Mixing zone" means that portion of a water body where a point source discharge or venting groundwater is mixed with receiving water.

    (b) "Venting groundwater" means groundwater that is entering a surface water of the state from a facility, as defined in section 20101.