· (6) pHffi -NJ (Na+) (Ca2+) (Fe2+) Mn (A13+) (H2Si03) (HBO) 20 El 17.4 20 ) 59.6 9.0 208 0.9996 9.01 1.32 (mval) 23.8 0.02 0.02 0.07 0.00 0.00 0.00 23.9 (mg) 12.3 19.5 31.8 0.003