Simazine is one of the most heavily used herbicides and has been reported in drinking water in the United States. It is considered a priority chemical for testing in drinking water. Therefore, there is much interest in removing simazine from water runoff prior to its entering lakes, rivers and ponds. This study was conducted to delineate removal of simazine from water by adsorption using peat moss. The adsorption capacity of autoclaved sphagnum peat screenings, which are used primarily for heavy metals removal at industrial sites (HMP), was studied for the removal of simazine. Approximately 35% of the simazine was adsorbed by the peat moss. The solid-water simazine distribution ratio and rate constant for the HMP peat were determined from batch isotherm and kinetic studies, respectively. From column studies, the breakthrough curve of simazine was obtained. The solid-water simazine distribution ratio, Kd,was determined from the column study by proposing a linear equilibrium transport model. Studies showed that simazine was adsorbed within 3 hr to the available peat moss surfaces and reached equilibrium in a short time (<4 hr). In addition to adsorption of simazine by peat moss, microbial degradation of simazine in peat moss is being studied. By combining both simazine adsorption and degradation in peat moss filters, the filters can properly be designed for field use.