Evaluation of NOM Characteristics and Disinfection By-Products (DBPs) Formation Potential in Nakdong River Basin

Abstract

In this study, NOM characteristics and disinfection by-products (DBPs) formation potential using LC-OCD were evaluated for main stream and tributaries from upstream to downstream of Nakdong River basin by season and sampling site. The concentration of chlorophyll-a (Chl-a) at the main stream tended to increase gradually from upstream to downstream, however the correlation with DOC concentration was not high. The DOC concentration of main stream is considered to be influenced by the adjacent tributary rather than Chl-a. In the case of NOM in the main stream, HS was dominant with 51.2~59.3%, followed by BB (17.5~19.1%), LMWs (13.4~17.6%) and BP (8.4~14.3%), respectively. The aromacity and average molecular weight of HS, the dominant NOM compound, were investigated, and the aromacity and average molecular weight were higher in the downstream than in the upstream and decreased in the midstream where sewage effluent was introduced. In the case of DBPs, THMFP and HAAFP were relatively higher in the mid-and down-stream than in the upstream. The correlation between DOC component concentration and DBPFP concentration showed the highest correlation with HS and THMFP concentration of 0.70.