An industrial plant is proposing to discharge treated effluent at an average flowrate of 55 L s into a nearby watercourse which has the following upstream characteristics:- 95% ile flowrate BODS Nitrate (NO3-N) Ortho Phosphate (PO-P) It has been stipulated by the licensing authority that the maximum allowable concentrations in the watercourse downstream of the discharge point are as follows:- BOD, Nitrate (NO3-N) Ortho Phosphate (PO4-P) 2.5 m s 0.5 mg L- 4.0 mg L- 0.5 g L (i) BODS: (ii) NO3-N; (iii) PO-P. 1.0 mg L- 5.0 mg L- 1.5 g L- Assuming conservation of mass and complete transverse mixing across the width of the watercourse, determine the required treated effluent emission standards in terms of the following:- A subsequent review of the receiving water quality by the EPA has concluded that the annual PO-P load should be limited to 20 kg. Establish the revised treated effluent PO4-P discharge standard to comply with this requirement. Describe briefly how the reduced PO-P discharge standard might be achieved.