The February 2024 regulation text amends California Code of Regulations section 64431, Table 64431-A, for primary maximum contaminant levels for inorganic chemicals in public water systems. HMI records the metal and metalloid MCL rows in the table, including the newly adopted hexavalent chromium MCL.
Update history
The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.
| Commit | Date | Change | Description |
|---|---|---|---|
| a8052bb | 2026-08-09 | minor | Narrative text revised |