Variables: total_organic_carbon pH Systems: groundwater Substances: 2 -2 -Difluorodeoxyuridin (FIRDBEQIJQERSE-QPPQHZFASA-N) 4-Hydroxy-1-(2-hydroxyethyl)-2-2-6-6-tetramethylpiperidine (STEYNUVPFMIUOY-UHFFFAOYSA-N)