SEASONAL-VARIATIONS IN HUMIC SUBSTANCES AND THEIR REDUCTION THROUGH WATER-TREATMENT PROCESSES

The apparent molecular mass concentrations of dissolved humic substanc es from the Detroit River and treated water from the Windsor Water Tre atment Plant were determined by gel permeation chromatography over a 1 -year period. The results of this research show significant seasonal v ariations in humic substance concentrations and these values are influ enced by the turnover of water bodies. The gel permeation chromatogram s of the samples indicate that there is a gradual reduction in the con centration of humic substances during the treatment process, the great est change occurring after coagulation-sedimentation process. In this process, 76%, 40%, and 30% of the high. intermediate, and low molecula r mass compounds, respectively, were either transformed in chemical co mposition or removed. Other parameters such as turbidity, chlorine dem and (during prechlorination), and trihalomethanes concentration in the treated water were also analyzed and there appears to be a relationsh ip between them. When the humic substance concentrations are high, gen erally the turbidity, chlorine demand, and total trihalomethanes conce ntrations in the drinking water are also high.