Investigations for a tank leaching test for PCB, OCB and EOX
Ontwikkeling van een diffusieproef voor PCB, OCB en EOX
van der Velde EG, Broekman MH, Orbons AJ
RIVM Report 771402025
Within the framework of the Terms of Reference Plan for normalization commission 39011 on "Leaching characteristics of building and waste materials", the National Institute of Public Health and the Environment (RIVM) is developing a set of leaching tests for various organic compounds. Laboratory investigations for the development of tank leaching tests PCB, organochlorine pesticides (OCB) and extractable organic halogenated compounds (EOX) were performed between 1994-1997 to assess the practical feasibility of the experimental set-up, the level of emissions, the reproducibility of the experiments and the mechanism of the leaching of PAH. Additional experiments were performed to investigate the losses of OCB due to adsorption during the tank leaching test. Tank leaching tests for PCB, OCB and EOX, based on Dutch NEN 7345 and modified according to an internal RIVM method, were performed on four different cement-stabilized contaminated materials. The materials contained high levels of contaminants because it is expected that an important use of the tank leaching test will be the environmental assessment of stabilized wastes, which often have a high degree of contamination. These high levels also ensure detectable leached quantities. With reference to the performance, the modified method shows a good and practical feasibility of the test. Leachates seemed to be homogeneous enough to allow for partial extraction and analysis of (filtered) leachates. Losses of OCB due to (reversible) adsorption to the surface of the tank used for leaching were low. The level of emissions from the (highly contaminated) materials investigated was high enough to discriminate between different building and waste materials. Standard deviations (n=2) were comparable to those reported in Appendix A of NEN 7345. The mechanism of leaching of PCB, OCB and EOX from the materials investigated is not clear; this leaching may be due to a combination of several different mechanisms.