Appendix 4 to the RBCRs
Groundwater Protection Criteria
| Substance | GWPC in µg/L (ppb) |
|---|
| Volatile Organic Substances |
|---|
| Acetone | 700 |
| Acrylonitrile | 0.5 |
| Benzene | 1 |
| Bromoform | 4 |
| 2-Butanone (MEK) | 400 |
| Carbon tetrachloride | 5 |
| Chlorobenzene | 100 |
| Chloroform | 6 |
| Dibromochloromethane | 0.5 |
| 1,2-Dichlorobenzene | 600 |
| 1,3-Dichlorobenzene | 600 |
| 1,4-Dichlorobenzene | 75 |
| 1,1-Dichloroethane | 70 |
| 1,2-Dichloroethane | 1 |
| 1,1-Dichloroethylene | 7 |
| cis-1,2-Dichloroethylene | 70 |
| trans-1,2-Dichloroethylene | 100 |
| 1,2-Dichloropropane | 5 |
| 1,3-Dichloropropene | 0.5 |
| Ethyl benzene | 700 |
| Ethylene dibromide (EDB) | 0.05 |
| Methyl-tert-butyl-ether | 100 |
| Substance | GWPC in µg/L (ppb) |
|---|
| Volatile Organic Substances |
|---|
| Methyl isobutyl ketone | 350 |
| Methylene chloride | 5 |
| Styrene | 100 |
| 1,1,1,2-Tetrachloroethane | 1 |
| 1,1,2,2-Tetrachloroethane | 0.5 |
| Tetrachloroethylene | 5 |
| Toluene | 1,000 |
| 1,1,1-Trichloroethane | 200 |
| 1,1,2-Trichloroethane | 5 |
| Trichloroethylene | 5 |
| Vinyl chloride | 2 |
| Xylenes | 530 |
| Substance | GWPC in µg/L (ppb) |
| Semi-volatile Organic Substances |
| Acenaphthylene | 420 |
| Anthracene | 2,000 |
| Benzo(a)anthracene | 0.06 |
| Benzo(b)fluoranthene | 0.08 |
| Benzo(k)fluoranthene | 0.5 |
| Benzo(a)pyrene | 0.2 |
| Bis(2-chloroethyl)ether | 12 |
| Bis(2-chloroisopropyl)ether | 12 |
| Bis(2-ethyl hexyl)phthalate | 2 |
| Butyl benzyl phthalate | 1,000 |
| 2-chlorophenol | 36 |
| Di-n-butyl phthalate | 700 |
| Di-n-octyl phthalate | 100 |
| 2,4-Dichlorophenol | 20 |
| Fluoranthene | 280 |
| Fluorene | 280 |
| Hexachloroethane | 3 |
| Hexachlorobenzene | 1 |
| Naphthalene | 280 |
| Pentachlorophenol | 1 |
| Phenanthrene | 200 |
| Phenol | 4,000 |
| Pyrene | 200 |
| Substance | GWPC in µg/L (ppb) |
| Inorganic Substances |
| Antimony | 6 |
| Arsenic | 50 |
| Asbestos (in mfl) | 7 |
| Barium | 1,000 |
| Beryllium | 4 |
| Cadmium | 5 |
| Chromium (total) | 50 |
| Copper | 1,300 |
| Cyanide | 200 |
| Lead | 15 |
| Mercury | 2 |
| Nickel | 100 |
| Selenium | 50 |
| Silver | 36 |
| Thallium | 5 |
| Vanadium | 50 |
| Zinc | 5,000 |
| Substance | GWPC in µg/L (ppb) |
| Pesticides, PCBs and Extractable Total Petroleum Hydrocarbons |
| Alachlor | 2 |
| Aldicarb | 3 |
| Atrazine | 3 |
| Chlordane | 0.3 |
| Dieldrin | 0.002 |
| 2-4 D | 70 |
| Heptachlor epoxide | 0.2 |
| Heptachlor | 0.4 |
| Lindane | 0.2 |
| Methoxychlor | 40 |
| Simazine | 4 |
| Toxaphene | 3 |
| PCBs | 0.5 |
| Total Petroleum Hydrocarbon by EPA Method 418.1 (This method shall not be used for the analysis of samples collected after June 30, 2009) | 500 |
| Extractable Total Petroleum Hydrocarbons by CT ETPH Analysis (This method may be used for the analysis of samples collected on or after June 22, 1999) | 250 |
(Effective March 1, 2026)