Studies have demonstrated that hydrophobic organic compounds (HOC) show strong sorption to black carbon (BC). Therefore presence of BC in HOC contaminated sediment reduces the in situ freely dissolved aqueous concentration hence decrease uptake in biota. In connection with the research project “stability of polluted sediment” by the Norwegian Geotechnical Institute (NGI), sediment remediation with use of activated carbon (AC), which is a type of BC, is investigated. This thesis concentrates on two issues related to AC amendment, a chemical part and a physical part. In the chemical part, laboratory experiments with passive samplers have been carried out to test the effectiveness of AC amendment through quantification of freely dissolved aqueous concentration of PAH and PCB with and without AC amendment. In the physical part, various AC quantification techniques were tested to find a reliable method to quantify AC in sediment after amendment. From the chemical experiments it was evident that PAH and PCB showed stronger sorption to powdered AC than to granular AC. In the physical experiments the chemical wet oxidation (WO) procedure gave high AC recovery and showed promising results. In the chemo-thermal oxidation (CTO) method and the rinsing and thermal oxidation (RTO) procedure a strong catalytic effect was observed.