Table 17. Grade comparison of benthic animal index and water quality by survey site in Yangjaecheon

Site	Benthic Macroinvertebrate		Water Quality
	BMI		BOD*		TOC*		TP*
	Value	Grade	Con. (mg/L)	Grade	Con. (mg/L)	Grade	Con. (mg/L)	Grade
Juam bridge	55.1	C(usually)	0.7	Ia(very good)	2.0	Ia(very good)	0.040	II(slightly good)
Bodo bridge	61.1	C(usually)	0.6	Ia(very good)	1.9	Ia(very good)	0.040	Ib(good)
Daechi bridge	59.5.1	C(usually)	0.6	Ia(very good)	2.0	Ia(very good)	0.036	Ib(good)

Water quality and aquatic ecosystem standards are applied, and DO, SS and pH are all rated Ia (very good).