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e-CFR data is current as of September 24, 2020

Title 40Chapter ISubchapter DPart 141Subpart F → §141.51


Title 40: Protection of Environment
PART 141—NATIONAL PRIMARY DRINKING WATER REGULATIONS
Subpart F—Maximum Contaminant Level Goals and Maximum Residual Disinfectant Level Goals


§141.51   Maximum contaminant level goals for inorganic contaminants.

(a) [Reserved]

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

ContaminantMCLG (mg/l)
Antimony0.006
Arseniczero1
Asbestos7 Million fibers/liter (longer than 10 µm).
Barium2
Beryllium.004
Cadmium0.005
Chromium0.1
Copper1.3
Cyanide (as free Cyanide).2
Fluoride4.0
Leadzero
Mercury0.002
Nitrate10 (as Nitrogen).
Nitrite1 (as Nitrogen).
Total Nitrate + Nitrite10 (as Nitrogen).
Selenium0.05
Thallium.0005

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

[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]

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