Variables: total_organic_carbon pH Systems: groundwater Substances: 18-beta-Glycyrrhetinic acid (MPDGHEJMBKOTSU-YKLVYJNSSA-N) 2 -2 -Difluorodeoxyuridin (FIRDBEQIJQERSE-QPPQHZFASA-N) 1-Propanesulfonate (KCXFHTAICRTXLI-UHFFFAOYSA-N)