Evaluation of organic carbon migration and biomass formation on polymeric pipes using the modified BioMig
Thi Huyen Duong, Ji Won Park, Jin Hyung Noh, Sung Kyu Maeng*
Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Republic of Korea.
* e-mail correspondence: smaeng@sejong.ac.kr
Preferred topic #: Assimilable organic carbon, biofilm formation, modified BioMig, pathogens.
To evaluate the materials that in contact with drinking water with respect to biological contamination, organic carbon migration and biomass formation assays are widely employed. In previous studies, to conduct the assays, the entire material was exposed to the test water by submerging the material into glass jars. However, these are not realistic conditions since the water contact only the inner surface of the pipe in the distribution system, which may be different from the outer surface with respect to the coating layers. Furthermore, the extra components such as the containers and holders may be the sources of organic carbon contamination. Here, we introduced a minor but essential modification to the BioMig test, which is the most current test on the migration potential and biomass formation. In this modified BioMig method, the outer surface and cutting edges, which are not in contact with water in practical water distribution systems, would not be exposed to the test water. Moreover, the assimilable organic carbon formation potential via chlorination in the leachates was observed and recommended as an additional test in the migration potential assay. The modified test results demonstrated that polyethylene (PE) material is the most unfavorable material, notably when used in chlorinated drinking water. This proposed test provided an alternative approach to the decision-makers with respect to evaluating the pipe material characteristics.
