Abstract

In this study, we evaluated the impact of inland pollution sources on the sanitary status of seawater and shellfish (Short neck Clam) in the Narodo Area after 33.0 mm and 116.1 mm rainfall events. We analyzed the sanitary indicator microorganism such as coliform group, fecal coliform, Escherichia coli (E. coli) and Male-specific coliphage (MSC) in the discharge waters from the waste water treatment plants (WWTPs) and major inland pollution sources and also in seawater and shellfish for 3 or 4 days after 33.0 mm and 116.1mm rainfall events to determine how rainfall events increase the adverse impact of inland pollution sources on shellfish growing area . In the discharges from WWTPs, the range of coliform group and fecal coliform was 13-17,000 and 11-1,300 MPN/100 mL after 33.0 mm rainfall and was 490-35,000 and 330-13,000 MPN/100 mL after 116.1 mm rainfall events. Also, the range of fecal coliform and the radius of calculated impacted area of 5 major inland pollution sources contaminants was from 7.8 to 130,000 MPN/100 mL and from 4 to 960 m after 33.0mm rainfall and was from 79 to 540,000 MPN/100 mL and from 10 to 1,100 m after 116.1 mm rainfall events. The fecal coliform of seawaters from 16 stations in the designated area and 15 stations in the adjacent area ranged from < 1.8 to 17 and from < 1.8 to 14 MPN/100 mL, respectively. The E. coli level of shellfish at 4 stations in the designated area ranged from < 18 to 230 MPN/100 g.