40 CFR 141.51 : Protection Of Environment (§ 1.1 To Parts 1851-1899) — (§ 136.1 To § 149.111) — Environmental Protection Agency (Continued) (§ 136.1 To § 149.111) — Water Programs (Continued) (§ 136.1 To § 149.111) — National Primary Drinking Water Regulations (§ 141.1 To § 141.861) — Maximum Contaminant Level Goals And Maximum Residual Disinfectant Level Goals (§ 141.50 To § 141.55) — Maximum contaminant level goals for inorganic contaminants.

4 Aug 2016

(a) [Reserved]

(b) MCLGs for the following contaminants are as indicated:

Contaminant	MCLG (mg/l)
Antimony	0.006
Arsenic	zero ¹
Asbestos	7 Million fibers/liter (longer than 10 µm).
Barium	2
Beryllium	.004
Cadmium	0.005
Chromium	0.1
Copper	1.3
Cyanide (as free Cyanide)	.2
Fluoride	4.0
Lead	zero
Mercury	0.002
Nitrate	10 (as Nitrogen).
Nitrite	1 (as Nitrogen).
Total Nitrate + Nitrite	10 (as Nitrogen).
Selenium	0.05
Thallium	.0005

¹ This value for arsenic is effective January 23, 2006. Until then, there is no MCLG.

40 CFR 141.51

[50 FR 47155, Nov. 14, 1985, as amended at 52 FR 20674, June 2, 1987; 56 FR 3593, Jan. 30, 1991; 56 FR 26548, June 7, 1991; 56 FR 30280, July 1, 1991; 57 FR 31846, July 17, 1992; 60 FR 33932, June 29, 1995; 66 FR 7063, Jan. 22, 2001]