The results of experiments concerning iron and manganese removal from groundwater at a treatment facility in the first and second stage of filtration through pressure experimental filters with different filter beds are presented. Research was carried out on three parallel filters with the following filter beds: quartz sand+Hydrolit-Mn, quartz sand+pyrolusite and single medium mature quartz sand.
It was revealed that the effectiveness of iron and manganese removal from groundwater at the Sieradzka facility in Gdynia can be increased by one-stage filtering through oxidation beds of mature quartz sand or two-layered quartz sand+pyrolusite. As a result of filtration, the concentrations of both elements decreased from the average level in untreated water of 1.10 mg Fe/dm3 and 0.14 mg Mn/dm3 to below 0.2 mg Fe/dm3 and 0.05 mg Mn/dm3 in the outflow. These levels meet both the current Polish and European Union standards.