Cal. Code Regs. Tit. 22, § 64431 - Maximum Contaminant Levels-Inorganic Chemicals

Public water systems shall comply with the primary MCLs in table 64431-A as specified in this article.

Table 64431-A

Maximum Contaminant Levels Inorganic Chemicals

	Chemical	Maximum Contaminant Level, mg/L
	Aluminum	1.
	Antimony	0.006
	Arsenic	0.010
	Asbestos	7 MFL*
	Barium	1.
	Beryllium	0.004
	Cadmium	0.005
	Chromium	0.05
	Cyanide	0.15
	Fluoride	2.0
	Hexavalent chromium	0.010
	Mercury	0.002
	Nickel	0.1
	Nitrate (as nitrogen)	10.
	Nitrate+Nitrite (sum as nitrogen)	10.
	Nitrite (as nitrogen)	1.
	Perchlorate	0.006
	Selenium	0.05
	Thallium	0.002

* MFL=million fibers per liter; MCL for fibers exceeding 10 µm in length.

Notes

Cal. Code Regs. Tit. 22, § 64431

1. Amendment of article heading, repealer of section and renumbering and amendment of former section 64435 to section 64431 filed 9-8-94 as an emergency; operative 9-8-94 (Register 94, No. 36). A Certificate of Compliance must be transmitted to OAL by 1-6-95 or emergency language will be repealed by operation of law on the following day. For prior history, see Register 88, No. 51.
2. Amendment of article heading, repealer of section and renumbering and amendment of former section 64435 to section 64431 refiled 1-3-95 as an emergency; operative 1-3-95 (Register 95, No. 1). A Certificate of Compliance must be transmitted to OAL by 5-3-95 or emergency language will be repealed by operation of law on the following day.
3. Amendment of article heading, repealer of section, and renumbering and amendment of former section 64435 to section 64431 refiled 4-26-95 as an emergency; operative 4-26-95 (Register 95, No. 17). A Certificate of Compliance must be transmitted to OAL by 8-24-95 or emergency language will be repealed by operation of law on the following day.
4. Certificate of Compliance as to 4-26-95 order transmitted to OAL 5-5-95 and filed 6-19-95 (Register 95, No. 25).
5. Amendment of subsection (a) and table 64431-A, repealer of table 64431-B and subsection (b) and amendment of NOTE filed 3-23-98; operative 4-22-98 (Register 98, No. 13).
6. Amendment of Table 64431-A and amendment of NOTE filed 5-13-2003; operative 6-12-2003 (Register 2003, No. 20).
7. Amendment of section and NOTE filed 9-18-2007; operative 10-18-2007 (Register 2007, No. 38).
8. Amendment of subsection (a) -- Table 64431-A and amendment of NOTE filed 10-29-2008; operative 11-28-2008 (Register 2008, No. 44).
9. Amendment of section and NOTE filed 5-28-2014; operative 7-1-2014 (Register 2014, No. 22).
10. Change without regulatory effect amending Table 64431-A and NOTE filed 7-16-2015 pursuant to section 100, title 1, California Code of Regulations (Register 2015, No. 29).
11. Change without regulatory effect amending Table 64431-A filed 9-11-2017 pursuant to section 100, title 1, California Code of Regulations (Register 2017, No. 37).

Note: Authority cited: Sections 116271, 116293(b), 116350, 116365, 116365.5 and 116375, Health and Safety Code. Reference: Sections 116365, 116365.5 and 116470, Health and Safety Code.

1. Amendment of article heading, repealer of section and renumbering and amendment of former section 64435 to section 64431 filed 9-8-94 as an emergency; operative 9-8-94 (Register 94, No. 36). A Certificate of Compliance must be transmitted to OAL by 1-6-95 or emergency language will be repealed by operation of law on the following day. For prior history, see Register 88, No. 51.
2. Amendment of article heading, repealer of section and renumbering and amendment of former section 64435 to section 64431 refiled 1-3-95 as an emergency; operative 1-3-95 (Register 95, No. 1). A Certificate of Compliance must be transmitted to OAL by 5-3-95 or emergency language will be repealed by operation of law on the following day.
3. Amendment of article heading, repealer of section, and renumbering and amendment of former section 64435 to section 64431 refiled 4-26-95 as an emergency; operative 4-26-95 (Register 95, No. 17). A Certificate of Compliance must be transmitted to OAL by 8-24-95 or emergency language will be repealed by operation of law on the following day.
4. Certificate of Compliance as to 4-26-95 order transmitted to OAL 5-5-95 and filed 6-19-95 (Register 95, No. 25).
5. Amendment of subsection (a) and table 64431-A, repealer of table 64431-B and subsection (b) and amendment of Note filed 3-23-98; operative 4-22-98 (Register 98, No. 13).
6. Amendment of Table 64431-A and amendment of Note filed 5-13-2003; operative 6-12-2003 (Register 2003, No. 20).
7. Amendment of section and Note filed 9-18-2007; operative 10-18-2007 (Register 2007, No. 38).
8. Amendment of subsection (a) - Table 64431-A and amendment of Note filed 10-29-2008; operative 11-28-2008 (Register 2008, No. 44).
9. Amendment of section and Note filed 5-28-2014; operative 7/1/2014 (Register 2014, No. 22).
10. Change without regulatory effect amending Table 64431-A and Note filed 7-16-2015 pursuant to section 100, title 1, California Code of Regulations (Register 2015, No. 29).

The amended version of this section by Register 2024, No. 31, effective 10/1/2024 is not yet available.