Environmental Protection Agency 

contaminant I MCLGn In 

m9 

(28) Endrin ............................................................. .002 

(27) Glyphosate ..................................................... .7 

(28) Nexachbrocydopentadiene ........................... .05 

(29) Oxamyl (Nydate) ............................................ .2 

(30) Ptdoram ......................................................... .5 

(31) Simazine ........................................................ .004 

(32) 1.2.4-TriChla'obenzene .................................. .07 

(33) 1,1,2-T6ohloroethane ..................................... .003 

[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] 

§ 141.51 Maximum contaminant level 

goals for inorganic contaminants. 

(a) [Reserved] 

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

Contaminant MCLG (mg+l) 

Antimony ...................................... 0.006 

Arsenic ......................................... zero+ 

Asbestos ...................................... 7 Mlllion fibersAiter 

(longer than 10 pm). 

Barium ......................................... 2 

Beryllium ...................................... .004 

Cadmium ..................................... 0.005 

Chromium .................................... 0.1 

Copper ......................................... 1.3 

Cyanide (as free CyarNde) .......... .2 

Fluonde ........................................ 4.0 

Lead ............................................. zero 

Mercury ........................................ 0.002 

Nitrate .......................................... 10 (as Nitrogen). 

NitAte ........................................... 1 (as Nitrogen). 

Total Nitr'ate+Nitnte ..................... 10 (as Nitrogen). 

Selerium ...................................... 0.05 

Thallium ....................................... .0005 

This value for arsenio is effective January 23, 2006. Untll 

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] 

§ 141.52 Maximum contaminant level 

goals for microbiological contaminants. 

MCLGs for the following contaminants are as indicated: 

Contaminant MCLG 

(1)Giardi8 lamblia ........................................ zero 

(2) Viruses .................................................... zero 

(3)Le9ionel/a ................................................ zero 

(4) Total odifonns (nduding fecal odiforms zero. 

and Eseheriehia colfj. 

(5)Cryptospo6dium ...................................... zero. 

[54 FR 27527, 27566, June 29, 1989; 55 FR 25064. 

Jtxne 19, 1990; 63 FR 69515, Dec. 16. 1998] 

§ 141.60 

§ 141.53 Maximum eontaminant level 

goals for disinfection byproducts. 

MCLGs for the following disinfection 

byproducts are as indica.ted: 

Disinfeclion byprodud ~G 

BromoAiddoromethane ............................................ zero 

Bromofonn ............................................................... zero 

Bromate ................................................................... zero 

Chlorite.................................................................... 0.8 

Chlorofonn............................................................... 0.07 

Dibromochloromethane ........................................... 0.08 

Dichloroaoetic acld .................................................. zero 

Monochloroaoetic add ............................................. 0.07 

Trichloroacetio acid .................................................. 0.02 

[63 FR 69465, Dec. 16, 1998, as amended at 65 

FR 34405, May 30, 2000; 71 FR 478, Jan. 4, 2006] 

§ 141.54 Maziruum residual disinfect• 

ant level goals for disinfectants. 

MRDLGs for disinfectants are as follows: 

Disinfectant residual MRDLG(mg4) 

ChloAne ................................................ 4 (as CI=). 

Chloramines ......................................... 4 (as C12). 

ChloAne dioxide ................................... 0.8 (as CIO2) 

[63 FR 69465, Dec. 16, 19981 

§ 141.55 Maximum contaminant level 

goals for radionuclides. 

MCLGs for radionuclides are as indica.ted in the following table: 

Contaminant MCLG 

1. Combined radium-228 and radium-228 .............. Zero. 

2. Gross alpha partlde activity (exduding radon Zero. 

and uranium). 

3. Beta partide and photon radoac6vity ................ Zero. 

4. Urar11un1 ............................................................... 7ero. 

[65 FR 76748, Dec. 7, 2000] 

Subpart C—National Primary 

Drinking Water Regulations: 

Maximum Contaminant Levels 

and Maximum Residual Disinfectant Levels 

§ 141.60 Effective dates. 

(a) The effective dates for § 141.61 are 

as follows: 

(1) The effective date for paragraphs 

(a)(1) through (a)(8) of § 141.61 is January 9, 1989. 

(2)The effective date for paragraphs 

(a)(9) through (a)(18) a.nd (c)(1) through 

(c)(18) of §141.61 is July 30, 1992. 

449 

§ 141.61 

(3) The effective date for paragraphs 

(a)(19) through (a)(21), (c)(19) through 

(c)(25), and (c)(27) through (c)(33) of 

§ 141.61 is January 17, 1994. The effective 

date of § 141.61(c)(26) is August 17, 1992. 

(b) The effective dates for § 141.62 are 

as follows: 

(1) The effective date of paragraph 

(b)(1) of §141.62 is October 2, 1987. 

(2) The effective date for paragraphs 

(b)(2) and (b)(4) through (b)(10) of 

11141.62 is July 30, 1992. 

(3)The effective date for paragraphs 

(b)(11) through (b)(15) of §141.62 is January 17, 1994. 

40 CFR Ch. 1(7-1-09 Edition) 

(4) The effective date for § 141.62(b)(16) 

is January 23, 2006. 

[56 FR 3593, Jan. 30, 1991, as amended at 57 

FR 31846, July 17, 1992; 59 FR 34324, July 1, 

1994; 66FR. 7063, Jan. 22, 2001) 

§ 141.61 Maximum contaminant levels 

for organic contaminants. 

(a) The following maximum contaminant levels for organic contaminants 

apply to community and non-transient, 

non-community water systems. 

CAS No. Contaminant MCL (mgO) 

(1) 75-01-4 ............................................................ Vinyl chbnde ............................................................. 0.002 

(2)71-43-2 ............................................................ Benzene .................................................................... 0.005 

(3)56-23j ............................................................ Carbon tetraoNortde .................................................. 0.005 

(4) 107-06-2 .......................................................... 1,2-Dichloroethane .................................................... 0.005 

(5)79-01-6 ............................................................ Trichloroethyfene ....................................................... 0.005 

(6) 108-46-7 .......................................................... para-0ichlorobenzene ............................................... 0.075 

(7)75-35-4 ............................................................ 1.1-D1cHoroethylene .................................................. 0.007 

(8)71-55-6 ............................................................ 1,1,1-Tfichloroethane ................................................ 0.2 

(9) 166v9-2 .......................................................... cls-1,2-Dichloroethylene ............................................ 0.07 

(10)78-87-5 .......................................................... 1,2-Dichloropropane .................................................. 0.005 

(11)100-41-4 ........................................................ Ethylbenzene ............................................................. 0.7 

(12)109-90-7 ........................................................ MonoCNorobenzene .................................................. 0.1 

(13)95-50-1 .......................................................... o-DicNorobenzene .................................................... 0.6 

(14)100-42-6 ........................................................ Styrene ...................................................................... 0.1 

(15)127-18-4 ........................................................ Tetrachloroethylene ................................................... 0.005 

(16) to6-88-3 ........................................................ Toluene ...................................................................... 1 

(17)156-4W-5 ........................................................ tranfr1,2-Dichloroethylene ........................................ 0.1 

(18)1330-20-7 ...................................................... Xylene5 (total) ........................................................... 10 

(19)75-09-2 .......................................................... Dichloromethane ....................................................... 0.005 

(20)120--82-1 ........................................................ 1,2,4-TricNoro- benzene ........................................... .07 

(21)79-00-5 .......................................................... 1,1,2-TricNoro- ethane .............................................. .005 

(b) The Administrator, pursuant to 

section 1412 of the Act, hereby identifies as indicated in the Table below 

granular activated carbon (GAC), 

packed tower aeration (PTA), or oxidation (OX) as the best technology treatment technique, or other means available for achieving compliance with the 

maximnm contaminant level for organic contaminants identified in paragraphs (a) and (c) of this section: 

BAT FOR ORGANIC CONTAMINANTS LISTED IN § 141.61 (a) AND (o) 

CAS No. Contaminant GAC PTA OX 

15972--60-8 .................................... Alachlor .............................................................................. X .............. .............. 

116-06-3 ........................................ Aldioatb .............................................................................. X .............. .............. 

1646-66-4 ...................................... Aldicaib sulfone ................................................................. x .............. .............. 

1646 87-3 ...................................... Aldicarb sulroxide .............................................................. x .............. .............. 

1912-24-9 ...................................... Atrazine ............................................................................. X .............. .............. 

71-43-2 .......................................... 8enzene ............................................................................ X X .............. 

50-32-8 .......................................... Benzofalpyrene ................................................................. X .............. .............. 

156"6-2 ...................................... Carbofuran ......................................................................... X .............. .............. 

56-23-6 .......................................... Carbon tetrachloride .......................................................... X X .............. 

57-74-9 .......................................... Chlordane .......................................................................... X .............. .............. 

75-99-0 .......................................... Dalapon ............................................................................. X .............. .............. 

94-75-7 .......................................... 2,4-D .................................................................................. X .............. .............. 

103-23r1 ........................................ Di (2-ethN") adipate ................................................... X X .............. 

117-81-7 ........................................ Df (2-ethylheXyi) phthdlale ................................................ X .............. .............. 

96-12--8 .......................................... Dibromochloropropane (DBCP) ........................................ X X .............. 

95~i0~ -1 .......................................... o-DicNorobenzene ............................................................ X X .............. 

108-46-7 ........................................ oara-DicNorobenzene ....................................................... X X ............., 

450 

Environrnental Protection Agency § 141.61 

BAT FOR ORGANiC CONTAMINANTS LISTED IN § 141.61 (a) AND (C)—(:ontlnued 

CAS No. Contaminant GAC PTA OX 

107--06-2 ........................................ 1.2-Dichloroethane ............................................................ x x .............. 

75-95-4 .......................................... 1.1-Diohloroethylene .......................................................... X X .............. 

156-59-2 ........................................ cts-1,20chloroe1hytene .................................................... X X .............. 

156--60-5 ........................................ trans-1.2-DiOhloroethylene ................................................ X X .............. 

75 -09-2 .......................................... DichloromeMane ............................................................... .............. X .............. 

78-87-5 .......................................... 1,2-Didtloropropane .......................................................... X X .............. 

88-85-7 .......................................... Oinoseb ............................................................................. X .............. .............. 

85-00-7 .......................................... Olquat ................................................................................ X .............. .............. 

145-73-3 ........................................ Endothall............................................................................ X .............. .............. 

72-20-8 .......................................... Endrin ................................................................................ x .............. .............. 

100-41-4 ........................................ Ethylbeniene ..................................................................... X X .............. 

106-93-4 ........................................ Eth ene Dibromide EDB ........... YI ( ..................................... X X .............. 

1071 -83-6 ...................................... Gylphosate ........................................................................ .............. .............. x 

7634-8 .......................................... Hepta0hl0r ......................................................................... X .............. .............. 

1024-57-3 ...................................... Heptachlor epoxide ........................................................... X .............. .............. 

118-74-1 ........................................ Hexachlorobenzene ........................................................... X .............. .............. 

77-47-3 .......................................... FiexaOhlorOCydopentadiene .............................................. X x .............. 

58-89-9 .......................................... Lindane .............................................................................. X .............. .............. 

72-43-5 .......................................... Methoxychlor ..................................................................... x .............. .............. 

108-90-7 ........................................ Monochlorobenzene .......................................................... X X .............. 

23135-22-0 .................................... Oxamyl (vydate) ................................................................ X .............. .............. 

87-86-5 .......................................... Pentachlorophend ............................................................. X .......... .............. 

1918-02-1 ...................................... Pidoram ............................................................................. x .............. .............. 

1336-36-3 ...................................... Polyohlorinated biphenyta (PCB) ....................................... x .............. .............. 

12234-9 ........................................ Sima2lne ............................................................................ X .............. .............. 

100-42-5 ........................................ Styrene .............................................................................. X X .............. 

1746-01 ~'i ...................................... 2.3.7.8-TCDD (Dloxin) ....................................................... X .............. .............. 

127-18-4 ........................................ TeVaOhlorOethylene ........................................................... x X .............. 

108,88-8 ........................................ Toiuene .............................................................................. X x .............. 

800145-2 ...................................... Toxaphene ......................................................................... x .............. .............. 

93-72-1 .......................................... 2,4,5-TP (Silvex) ................................................................ X .............. .............. 

120-82-1 ........................................ 1,2,4-Trichlorobenzene ...................................................... X X .............. 

71 -55-6 .......................................... 1,1,1-TrI0hl0roethane ........................................................ x X .............. 

79-00-6 .......................................... 1,1.2-Trichloroethane ........................................................ X X .............. 

79-01-6 .......................................... Trichloroethylene ............................................................... X x .............. 

75-01-4 .......................................... Vinyl chloride ..................................................................... .............. x .............. 

1330-20-7 ...................................... Xylene ................................................................................ x X .............. 

(c) The following magimum contami- systems and non-transient, non-comnant levels for synthetic organic con- munity water systems: 

taminants apply to community water 

CAS No. Contaminent MCL (mgA) 

(1) 15972-.60--8 ...................................................... AlacNor .................................. .................................... 0.002 

(2) 116-06-3 ........................................................... Aldicarb ...................................................................... 0.003 

(3) 164s-87-3 ......................................................... Aldicatb sulfoxide ...................................................... 0.004 

(4) 1646-87-4 ......................................................... Aldicaib Sultonb ......................................................... 0.002 

(5) 1912-24 9 ........................................................ Atrazine ..................................................................... 0.003 

(6) 1563-66-2 ........................................................ Carboturan ................................................................. 0.04 

(7) 57-74-9 ............................................................ Chbrdane .................................................................. 0.002 

(8) 96-12-8 ............................................................ Dibromochloropropene .............................................. 0.0002 

(9) 94-75-7 ............................................................ 2.4-D .......................................................................... 0.07 

(10) 106-93-4 .......................................................... Ethylene dibromide .................................................... 0.00005 

(11) 76-44-8 ............................................................ Heptachlor ................................................................. 0.0004 

(12) 1024-57-3 ........................................................ Heptachlor epoxide ................................................... 0.0002 

(13) 58-89-9 ............................................................ Lindane ...................................................................... 0.0002 

(14) 72-43-5 ............................................................ MethOxyChlOr ............................................................. 0.04 

(15) 1336-06-3 ........................................................ POlyOt>forinated biphenyls .......................................... 0.0005 

(16) 87-86r5 ............................................................ Pentachlorophand ..................................................... 0.001 

(17) 8001-05-2 ........................................................ Toxaphene ................................................................. 0.003 

(18) 93-72-1 ............................................................ 2.4.5-TP ..................................................................... 0.05 

(19) 50-32-8 ............................................................ Benzaalplaene ......................................................... 0.0002 

(20) 75-99-0 ............................................................ Dalapon ..................................................................... 0.2 

(21) 103-23-1 .......................................................... Di(2-ethylhexyl) adipate ............................................. 0.4 

(22) 117,81 7 .......................................................... Di(2-ethy1hexyl) phthalate .......................................... 0.006 

(23) 88-85-7 ............................................................ Dinoseb ..................................................................... 0.007 

(24) 85-00-7 ............................................................ Diquat ........................................................................ 0.02 

(25) 145-73-3 .......................................................... Endothall .................................................................... 0.1 

451 

§ 141.62 40 CFR Ch. 1(7-1-09 Edition) 

CAS No. Contaminant MCL (mg4) 

(26)72-20-8 ............................................................ Endrin ........................................................................ 0.002 

(27)1071-53-6 ........................................................ Glyphosate ................................................................ 0.7 

(28) 118-74-1 .......................................................... Hexachotorbenzene ................................................... 0.001 

(29) 77-47-4 ............................................................ Hexachlorocydopentadiene ...................................... 0.05 

(30) 23135-22-0 ...................................................... OxamN (Vydate) ........................................................ 0.2 

(31) 1918-02-1 ........................................................ Pidoram ..................................................................... 0.5 

(32) 122 34-9 .......................................................... Simazine .................................................................... 0.004 

(33) 1746-01~i ' ........................................................ 2.3,7,8-TCDD (Dlo) in) ............................................... 3x10V e 

[56 FR 3593, Jan. $0, 1991, as amended at 56 FR 30280, July 1, 1991; 57 FR 31846, July 17, 1992; 

59 FR 34324, July 1, 1994] 

§ 141.62 Maximum contaminant levels 

for inorganic contaminants. 

(a) [Reserved] 

(b) The maximum contaminant levels 

for inorganic contaminants specified in 

paragraphs (b) (2)-(6), (b)(10), and (b) 

(11){16) of this section apply to community water systems and non-transient, non-Oommunity water systems. 

The maximum contaminant level specifled in paragraph (b)(1) of this section 

only applies to commtulity water systems. The maximum contaminant levels specified in (b)(7), (b)(8), and (b)(9) 

of this section apply to community 

water systems; non-transient, noncommunity wa.ter systems; and transient non-community water systems. 

Contaminant I MCL (mgA) 

(1) Fluoride ............................ 4.0 

(2) Asbeetoe .......................... 7 Million Fibersfliter (longer 

tlian 10 μm). 

(3) Bariun .............................. 2 

(4) Cadmium .......................... 0.005 

(5) Chromium ......................... 0.1 

(6) Merary ............................ 0.002 

(7) Nitrate ............................... 10 (as Nitrogen) 

(8) Nitrite ................................ 1 (as Nitrogen) 

(9)Total Nitrate and Nitrite .... 10 (as NiVogen) 

(10) Selenium ........................ 0.05 

(11)Antimony ........................ 0.006 

(12) Beryllium ........................ 0.004 

(13)Cyanide (as free Cya- 0.2 

nlde). 

(14)(Reserved). 

(15) Thaltium .......................... 0.002 

(16) Arsenic ........................... 0.010 

(c) The Administrator, pursuant to 

section 1412 of the Act, hereby identifies the following as the best technology, treatment technique, or other 

means available for aehieving compliance with the maximum contaminant 

levels for inorganic contaminants identified in paragraph (b) of this section, 

except fluoride: 

BAT FOR INORGANIC COMPOUNDS LISTED IN 

SECTION 141.62(b) 

ChemiCBl Name BAT(s) 

Antimony........................................................ 2.7 

Arserge 4 ......................................................... 1. 2, 5, 6. 7. 9, 

12 6 

Asbestos ........................................................ 2.3.8 

BaAum ........................................................... 5,6.7.9 

Beryllium ........................................................ 1,2.5.6.7 

Cadmlum ....................................................... 2.5.6.7 

Chromlum ...................................................... 2.5.6 2,7 

Cyanide .......................................................... 5,7.13 

Meraury .......................................................... 2 1 ,4,6 1 .7' 

Nickel............................................................. 5.6,7 

Nitrate............................................................ 5,7,9 

Nitrite............................................................. 5.7 

SeleNum ........................................................ 1.2 3,6.7,9 

Thalllum ......................................................... 1,5 

BAT onty if influent Hg eonoentrations 51099+1. 

z BAT for Chromium III only. 

3 BAT for Selenlum IV only. 

^ BATs for Arsenic V. Prewxidation may be required to oonvert ArSenic 111 to ArseniC V. 

bTo obtain hlgh removals, iron to arsenic ratio must be at 

least 20:1. 

Key to BATS in Table 

1 = Activated Alumina 

2= CoagulatiorVFiltration (not BAT for Syst,ems < 500 service connections) 

3= Direct and Diatomite Filt.ration 

4 = (3ranular Activated Carbon 

5 = Ion Exchange 

6= Lime Softening (not BAT for systems 

<500 service connections) 

7 = Reverse Osmosis 

8 = Corrosion Control 

9 = Electrodialysis 

10 = Chlorine 

11 = Ult.raviolet 

12 = Oxidation/Filtration 

13 = Alkaline Chlorination (pH Z8.5) 

(d) The Administrator, pursuant to 

section 1412 of the Act, hereby identifies in the following table the affordable technology, treatment technique, 

or other means available to systems 

serving 10,000 persons or fewer for 

aehieving compliance with the maximum contaminant level for arsenic: 

452