Definitions for "Mixing zone"
That portion of a water body adjacent to an effluent outfall where mixing results in the dilution of the effluent with the receiving water. Water quality criteria may be exceeded in a mixing zone as conditioned and provided for in WAC 173-201A-100.
A limited area or volume of water where initial dilution of a point source pollutant discharge takes place. The zone is extended to cover the secondary mixing in the surrounding waterbody. Numeric water quality criteria can be exceeded, but acutely toxic conditions are prevented from occurring in this zone. Also see "Clean Water Act," "National Pollutant Discharge Elimination System."
a defined area or volume of a receiving water surrounding by or adjacent to a wastewater discharge where the receiving water, as a result of the discharge, may not meet all applicable water quality criteria standards