The Calfhead stream (flow rate 0.05m3s-1) discharges into the Oxhead river (flow of 3.00 m3.s-1). It is proposed to discharge waste into the Calfhead stream but the EPA requires a stream mixing study be undertaken. A bromide tracer (conservative and not occurring naturally in either stream ) will be introduced into Calfhead stream. The detection limit for bromide is 1 mg.L-1. Calculate how much tracer must be introduced into Calfhead stream so that a detectable concentration is measured in Oxhead river downstream of their junction assuming complete mixing has occurred.