$rate= \frac{\left[X\right]\ast V}{SA\ast t\ast f_i}$
where
X is the	concentration of the analyte in the effluent, g/L;
V is the	volume of the collected effluent during the interval, L;
SA is the	surface area of the sample, m2;
t is the	duration of the interval, day; and
fi is the	normalization factor based on the mass % of analyte, unitless.