O Β¨rserum Bay is a semienclosed small bay on the Swedish east coast. A paper mill for recycled paper, situated by the bay, has released several hundred kilograms of polychlorinated biphenyls (PCBs) into the bay. A large part of the sediment was later dredged and placed in a deposit site on land. In the present investigation, the inventories of PCBs in the sediments outside the mill and various other matrices on the estate have been estimated. The release of PCBs to the surrounding environment via air, water in the bay, and groundwater was also assessed. The two major processes were volatilization from the deposit of contaminated sediments and release from bay sediments with subsequent advective water transport and volatilization. Estimates of the rate of removal in percent per year for different homolog groups clearly demonstrated that fluxes rather than concentrations should be considered in risk assessments of contaminated sites. The properties and location of the contaminated matrix governed the magnitude of the PCB leakage. In addition, the impact of physicochemical properties of the different PCB homolog groups on their environmental behavior was clear. The rate of removal from the deposit reached a maximum for tetrachlorobiphenyls (tetra-CBs), for which the rate was 0.03%/year. Measured volatilization transfer velocities in the soil at the deposit ranged from 3 Ο« 10 Οͺ11 to 1 Ο« 10 Οͺ8 cm/s. In the bay, the PCBs were much more mobile, even though there were smaller differences between the homolog groups. The dichlorobiphenyls (di-CBs) showed a rate of removal from the bay of 1.6 %/year. The rate decreased with increasing degree of chlorination up to pentachlorobiphenyls (penta-CBs). Pentachlorobiphenyls to octachlorobiphenyls (octa-CBs) were removed from the bay at a rate of 0.4 to 0.6%/year.