Liquids and sludges containing polychlorinated biphenyls (PCBs) can be treated to concentrate the PCBs in a solid residue. The latter can then be handled to destroy the PCBs. In the first part of this work, procedures are explored by which 2,3,4-trichlorobiphenyl (TCB) and 2,2',3,3',4,5,6-heptachlorobiphenyl (HeCB) are insolubilised, flocculated and removed from the water. The results demonstrate that application of Fe(III)-oxyhydroxide precipitation permits effective and reversible co-precipitation of TCB and HeCB. Fly ash from coal-fired thermal powerplants and CaO can be used as well for the rapid removal of TCB and HeCB. In the second part of this work, rapid insolubilisation followed by the degradation of TCB and HeCB by zero-valent iron powder in anaerobic batch systems is presented. Zero-valent iron was also used for the reductive dechlorination/remediation of TCB and HeCB sorbed on the fly ash and CaO particles. Overall, this paper describes a methodology to rapidly concentrate the PCBs from water and to concomitantly detoxify them in the concentrate by a chemical reductive process under ambient conditions of pH and temperature.