Appendix H - Water Quality Classifications and Standards The natural clarity shall not be conspicuously changed due to sediment or sediment laden discharge originating from the site of a land disturbance operation. There shall be no greater than 20% reduction in the visual clarity of the receiving water as measured by the horizontal sighting of a black disk; and/ or There shall be no greater than 15% increase in the turbidity of the receiving water as measured in NTU. Measurements are to be made immediately above or upstream of the discharge and below the discharge after reasonable mixing. For a description of the two methods refer to the Ministry for the Environment Water Quality Guidelines No. 2, Guidelines for the Management of Water Colour and Clarity, June 1994. See Chapter 25 Definitions for the definition of Reasonable Mixing. + Objectionable odour Shall not be emitted No numeric interpretation available + Suitability for consumption Shall not be rendered No numeric interpretation available by farm animals unsuitable + Aquatic life Shall not be any significant Light Penetration adverse effects In water deeper than half the euphotic depth, the euphotic depth shall not be changed by more than 10%. In waters shallower than half the euphotic depth, the lighting at the bed shall not be reduced by more than 20%. Ammonia Toxicity The four-day average concentration of total ammonia shall not exceed the following values Total Ammonia, NH4-N - (g/m³) pH <15°C 20° 25° 7.50 1.81 1.2 3 0.8 6 7.7 5 1.6 4 1.1 5 0.81 8.00 1.0 9 0.7 6 0.54 8.25 0.62 0.4 4 0.32 8.50 0.36 0.2 6 0.19 Note that daily average based on single sample taken noon - 2pm (NZST) Particulate Organic Material The daily average concentration of particate organic matter shall not exceed 4g/m³ Temperature Shall not be changed by more N/ A than 3°C. Shall not exceed 20°C. (Note that this is more stringent than the 25°C in the RMA Third Sched ule) Dissolved Oxygen Shall exceed 80% of saturation N/ A App H - 3