40 CFR Part 257, Appendix I
Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
| Chemical | CAS No. | MCL (mg/l) |
|---|---|---|
| Arsenic | 7440-38-2 | 0.05 |
| Barium | 7440-39-3 | 1 |
| Benzene | 71-343-2 | 0.005 |
| Cadmium | 7440-43-9 | 0.01 |
| Carbon tetrachloride | 56-23-5 | 0.005 |
| Chromium (hexavalent) | 7440-47-3 | 0.05 |
| 2,4-Dichlorophenoxy acetic acid | 94-75-7 | 0.1 |
| 1,4-Dichlorobenzene | 106-46-7 | 0.075 |
| 1,2-Dichloroethane | 107-06-2 | 0.005 |
| 1,1-Dichloroethylene | 75-35-4 | 0.007 |
| Endrin | 75-20-8 | 0.0002 |
| Fluoride | 7 | 4 |
| Lindane | 58-89-9 | 0.004 |
| Lead | 7439-92-1 | 0.05 |
| Mercury | 7439-97-6 | 0.002 |
| Methoxychlor | 72-43-5 | 0.1 |
| Nitrate | | 10 | |
| Selenium | 7782-49-2 | 0.01 |
| Silver | 7440-22-4 | 0.05 |
| Toxaphene | 8001-35-2 | 0.005 |
| 1,1,1-Trichloroethane | 71-55-6 | 0.2 |
| Trichloroethylene | 79-01-6 | 0.005 |
| 2,4,5-Trichlorophenoxy acetic acid | 93-76-5 | 0.01 |
| Vinyl chloride | 75-01-4 | 0.002 |
[56 FR 51016, Oct. 9, 1991]