(a) MCLGs are zero for the following contaminants:
(1) Benzene.
(2) Vinyl chloride.
(3) Carbon tetrachloride.
(4) 1,2-dichloroethane.
(5) Trichloroethylene.
(6) Acrylamide.
(7) Alachlor.
(8) Chlordane.
(9) Dibromochloropropane.
(10) 1,2-Dichloropropane.
(11) Epichlorohydrin.
(12) Ethylene dibromide.
(13) Heptachlor.
(14) Heptachlor epoxide.
(15) Pentachlorophenol.
(16) Polychlorinated biphenyls (PCBs).
(17) Tetrachloroethylene.
(18) Toxaphene.
(19) Benzo[a]pyrene.
(20) Dichloromethane (methylene chloride).
(21) Di(2-ethylhexyl)phthalate.
(22) Hexachlorobenzene.
(23) 2,3,7,8-TCDD (Dioxin).
(24) PFOA.
(25) PFOS.
(b) MCLGs for the following contaminants are as indicated:
Contaminant
| MCLG in mg/l
(unless otherwise noted)
|
---|
(1) 1,1-Dichloroethylene | 0.007
|
(2) 1,1,1-Trichloroethane | 0.20
|
(3) para-Dichlorobenzene | 0.075
|
(4) Aldicarb | 0.001
|
(5) Aldicarb sulfoxide | 0.001
|
(6) Aldicarb sulfone | 0.001
|
(7) Atrazine | 0.003
|
(8) Carbofuran | 0.04
|
(9) o-Dichlorobenzene | 0.6
|
(10) cis-1,2-Dichloroethylene | 0.07
|
(11) trans-1,2-Dichloroethylene | 0.1
|
(12) 2,4-D | 0.07
|
(13) Ethylbenzene | 0.7
|
(14) Lindane | 0.0002
|
(15) Methoxychlor | 0.04
|
(16) Monochlorobenzene | 0.1
|
(17) Styrene | 0.1
|
(18) Toluene | 1
|
(19) 2,4,5-TP | 0.05
|
(20) Xylenes (total) | 10
|
(21) Dalapon | 0.2
|
(22) Di(2-ethylhexyl)adipate | .4
|
(23) Dinoseb | .007
|
(24) Diquat | .02
|
(25) Endothall | .1
|
(26) Endrin | .002
|
(27) Glyphosate | .7
|
(28) Hexachlorocyclopentadiene | .05
|
(29) Oxamyl (Vydate) | .2
|
(30) Picloram | .5
|
(31) Simazine | .004
|
(32) 1,2,4-Trichlorobenzene | .07
|
(33) 1,1,2-Trichloroethane | .003
|
(34) Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) | 1 (unitless).
1
|
(35) HFPO-DA | 0.00001.
|
(36) PFHxS | 0.00001.
|
(37) PFNA | 0.00001.
|
Hazard Index = ([HFPO-DAwater ng/l]/[10 ng/l]) + ([PFBSwater ng/l]/[2000 ng/l]) + ([PFNAwater ng/l]/[10 ng/l]]) + ([PFHxSwater ng/l]/[10 ng/l])
HBWC = health-based water concentration
HQ = hazard quotient
ng/l = nanograms per liter
PFASwater = the concentration of a specific PFAS in water
[50 FR 46901, Nov. 13, 1985, as amended at 52 FR 20674, June 2, 1987; 52 FR 25716, July 8, 1987; 56 FR 3592, Jan. 30, 1991; 56 FR 30280, July 1, 1991; 57 FR 31846, July 17, 1992; 89 FR 32744, April 25, 2024]
(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
|
[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]
(a) MCLGs for the following contaminants are as indicated:
Contaminant
| MCLG
|
---|
(1) Giardia lamblia | zero
|
(2) Viruses | zero
|
(3) Legionella | zero
|
(4) Total coliforms (including fecal) | zero
|
coliforms and Escherichia coli
| |
(5) Cryptosporidium | zero
|
(6) Escherichia coli (E. coli) | zero |
(b) The MCLG identified in paragraph (a)(4) of this section is applicable until March 31, 2016. The MCLG identified in paragraph (a)(6) of this section is applicable beginning April 1, 2016.
[78 FR 10347, Feb. 13, 2013]
MCLGs for the following disinfection byproducts are as indicated:
Disinfection byproduct
| MCLG
(mg/L)
|
---|
Bromodichloromethane | zero
|
Bromoform | zero
|
Bromate | zero
|
Chlorite | 0.8
|
Chloroform | 0.07
|
Dibromochloromethane | 0.06
|
Dichloroacetic acid | zero
|
Monochloroacetic acid | 0.07
|
Trichloroacetic acid | 0.02 |
[63 FR 69465, Dec. 16, 1998, as amended at 65 FR 34405, May 30, 2000; 71 FR 478, Jan. 4, 2006]
MRDLGs for disinfectants are as follows:
Disinfectant residual
| MRDLG(mg/L)
|
---|
Chlorine | 4 (as Cl 2).
|
Chloramines | 4 (as Cl 2).
|
Chlorine dioxide | 0.8 (as ClO2) |
[63 FR 69465, Dec. 16, 1998]
MCLGs for radionuclides are as indicated in the following table:
Contaminant
| MCLG
|
---|
1. Combined radium-226 and radium-228 | Zero.
|
2. Gross alpha particle activity (excluding radon and uranium) | Zero.
|
3. Beta particle and photon radioactivity | Zero.
|
4. Uranium | Zero. |
[65 FR 76748, Dec. 7, 2000]