Fig. 4. Comparison of measured concentrations of propanil in the Axios River in 1994 with (a) the average daily predicted environmental concentrations of propanil in the simulated river for the 20-yr simulation period and (b) the daily predicted environmental concentrations of propanil in years when the minimum and maximum daily predicted environmental concentrations were observed. Error bars represent the standard deviation of the mean (n = 20 yr).