Variables: dissolved_oygen pH Systems: groundwater Substances: 1-Naphthylacetic acid (PRPINYUDVPFIRX-UHFFFAOYSA-N) 5-Chloro-2-methyl-4-isothiazolin-3-on (CMI) (DHNRXBZYEKSXIM-UHFFFAOYSA-N) 1-Propanesulfonate (KCXFHTAICRTXLI-UHFFFAOYSA-N) 2 -2 -Difluorodeoxyuridin (FIRDBEQIJQERSE-QPPQHZFASA-N)