An electrodialysis is used to treat a stream of 125 m3/d produced water with a salinity of 13,000 mg/L NaCl before the produced water is discharged to the river with the flow rate of 5 million L/d and salinity of 20 mg/L NaCl. The flow rate of the concentrated salt stream exiting the electrodialysis is 20 m3/d. Below the discharge point of the treated produced water is a prime sport fishing spot, and the fishes are intolerant to salt concentrations above 200 mg/L. What is the minimum removal efficiency of the electrodialysis? Assume that the density values of the concentrated salt stream and all of the untreated/ treated produced water streams are identical.