Section 611.311 MCLs for Organic Chemical Contaminants

Section 611

TITLE 35: ENVIRONMENTAL PROTECTION

SUBTITLE F: PUBLIC WATER SUPPLIES

CHAPTER I: POLLUTION CONTROL BOARD

PART 611 PRIMARY DRINKING WATER STANDARDS

SECTION 611.311 MCLS FOR ORGANIC CHEMICAL CONTAMINANTS

Section 611.311  MCLs for

Organic Chemical Contaminants

a)         Maximum Contaminant Levels for Volatile Organic Chemical

Contaminants. The MCLs for VOCs apply to CWS suppliers and NTNCWS suppliers:

CAS No.

Contaminant

MCL (mg/L)

71-43-2

Benzene

0.005

56-23-5

Carbon tetrachloride

0.005

95-50-1

o-Dichlorobenzene

0.6

106-46-7

p-Dichlorobenzene

0.075

107-06-2

1,2-Dichloroethane

0.005

75-35-4

1,1-Dichloroethylene

0.007

156-59-2

cis-1,2-Dichloroethylene

0.07

156-60-5

trans-1,2-Dichloroethylene

0.1

75-09-2

Dichloromethane (methylene

chloride)

0.005

78-87-5

1,2-Dichloropropane

0.005

100-41-4

Ethylbenzene

0.7

108-90-7

Monochlorobenzene

0.1

100-42-5

Styrene

0.1

127-18-4

Tetrachloroethylene

0.005

108-88-3

Toluene

1

120-82-1

1,2,4-Trichlorobenzene

0.07

71-55-6

1,1,1-Trichloroethane

0.2

79-00-5

1,1,2-Trichloroethane

0.005

79-01-6

Trichloroethylene

0.005

75-01-4

Vinyl chloride

0.002

1330-20-7

Xylenes (total)

10

b)         USEPA, under section 1412 of SDWA identifies in this

subsection (b) granular activated carbon (GAC), packed tower aeration (PTA), or

oxidation (OX) as BAT, treatment technique, or other means available for

achieving compliance with the MCLs for VOCs, and SOCs in subsections (a) and

(c) except for per-and polyfluoroalkyl substances (PFAS), as indicated:

CAS No

20-7

Xylenes (total)

10

b)         USEPA, under section 1412 of SDWA identifies in this

subsection (b) granular activated carbon (GAC), packed tower aeration (PTA), or

oxidation (OX) as BAT, treatment technique, or other means available for

achieving compliance with the MCLs for VOCs, and SOCs in subsections (a) and

(c) except for per-and polyfluoroalkyl substances (PFAS), as indicated:

CAS No.

Contaminant

BAT

15972-60-8

Alachlor

GAC

116-06-3

Aldicarb*

GAC

1646-87-4

Aldicarb sulfone*

GAC

1646-87-3

Aldicarb sulfoxide*

GAC

1912-24-9

Atrazine

GAC

71-43-2

Benzene

GAC, PTA

50-32-8

Benzo(a)pyrene

GAC

1563-66-2

Carbofuran

GAC

56-23-5

Carbon tetrachloride

GAC, PTA

57-74-9

Chlordane

GAC

94-75-7

2,4-D

GAC

75-99-0

Dalapon

GAC

96-12-8

Dibromochloropropane

GAC, PTA

95-50-1

o-Dichlorobenzene

GAC, PTA

106-46-7

p-Dichlorobenzene

GAC, PTA

107-06-2

1,2-Dichloroethane

GAC, PTA

156-59-2

cis-1,2-Dichloroethylene

GAC, PTA

156-60-5

trans-1,2-Dichoroethylene

GAC, PTA

75-35-4

1,1-Dichloroethylene

GAC, PTA

75-09-2

Dichloromethane

PTA

78-87-5

1,2-Dichloropropane

GAC, PTA

103-23-1

Di(2-ethylhexyl)adipate

GAC, PTA

117-81-7

Di(2-ethylhexyl)phthalate

GAC

88-85-7

Dinoseb

GAC

85-00-7

Diquat

GAC

145-73-3

Endothall

GAC

72-20-8

Endrin

GAC

106-93-4

Ethylene dibromide (EDB)

GAC, PTA

100-41-4

Ethylbenzene

GAC, PTA

1071-53-6

Glyphosate

OX

76-44-8

Heptachlor

GAC

1024-57-3

Heptachlor epoxide

GAC

118-74-1

Hexachlorobenzene

GAC

77-47-3

Hexachlorocyclopentadiene

GAC, PTA

58-89-9

Lindane

GAC

72-43-5

Methoxychlor

GAC

108-90-7

Monochlorobenzene

GAC, PTA

23135-22-0

Oxamyl

GAC

87-86-5

Pentachlorophenol

GAC

1918-02-1

Picloram

GAC

1336-36-3

Polychlorinated biphenyls

(PCB)

GAC

122-34-9

Simazine

GAC

100-42-5

Styrene

GAC, PTA

1746-01-6

2,3,7,8-TCDD

GAC

127-18-4

Tetrachloroethylene

GAC, PTA

108-88-3

Toluene

GAC, PTA

8001-35-2

Toxaphene

GAC

120-82-1

1,2,4-trichlorobenzene

GAC, PTA

71-55-6

1,1,1-Trichloroethane

GAC, PTA

79-00-5

1,1,2-trichloroethane

GAC, PTA

79-01-6

Trichloroethylene

GAC, PTA

93-72-1

2,4,5-TP

GAC

75-01-4

Vinyl chloride

PTA

1330-20-7

Xylene

GAC, PTA

(PCB)

GAC

122-34-9

Simazine

GAC

100-42-5

Styrene

GAC, PTA

1746-01-6

2,3,7,8-TCDD

GAC

127-18-4

Tetrachloroethylene

GAC, PTA

108-88-3

Toluene

GAC, PTA

8001-35-2

Toxaphene

GAC

120-82-1

1,2,4-trichlorobenzene

GAC, PTA

71-55-6

1,1,1-Trichloroethane

GAC, PTA

79-00-5

1,1,2-trichloroethane

GAC, PTA

79-01-6

Trichloroethylene

GAC, PTA

93-72-1

2,4,5-TP

GAC

75-01-4

Vinyl chloride

PTA

1330-20-7

Xylene

GAC, PTA

*See the Board

note at the end of this Section.

c)         The following maximum contaminant levels (MCLs) in Tables 1

and 2 to subsection (c) for synthetic organic contaminants apply to CWS and NTNCWS

suppliers; Table 2 also contains health-based water concentrations (HBWCs) for

selected per-and poly-fluoroalkyl substances (PFAS) used in calculating the

Hazard Index.

1)         MCLs for SOCs (except for PFAS) apply to CWS and NTNCWS

suppliers:

CAS Number

Contaminant

MCL (mg/L)

15972-60-8

Alachlor

0.002

116-06-3

Aldicarb*

0.003

1646-87-4

Aldicarb sulfone*

0.002

1646-87-3

Aldicarb sulfoxide*

0.004

1912-24-9

Atrazine

0.003

50-32-8

Benzo(a)pyrene

0.0002

1563-66-2

Carbofuran

0.04

57-74-9

Chlordane

0.002

94-75-7

2,4-D

0.07

75-99-0

Dalapon

0.2

96-12-8

Dibromochloropropane

0.0002

103-23-1

Di(2-ethylhexyl)adipate

0.4

117-81-7

Di(2-ethylhexyl)phthalate

0.006

88-85-7

Dinoseb

0.007

85-00-7

Diquat

0.02

145-73-3

Endothall

0.1

72-20-8

Endrin

0.002

106-93-4

Ethylene dibromide

0.00005

1071-53-6

Glyphosate

0.7

76-44-8

Heptachlor

0.0004

1024-57-3

Heptachlor epoxide

0.0002

118-74-1

Hexachlorobenzene

0.001

77-47-4

Hexachlorocyclopentadiene

0.05

58-89-9

Lindane

0.0002

72-43-5

Methoxychlor

0.04

23135-22-0

Oxamyl (Vydate)

0.2

87-86-5

Pentachlorophenol

0.001

1918-02-1

Picloram

0.5

1336-36-3

Polychlorinated biphenyls (PCBs)

0.0005

122-34-9

Simazine

0.004

1746-01-6

2,3,7,8-TCDD (Dioxin)

0.00000003

8001-35-2

Toxaphene

0.003

93-72-1

2,4,5-TP

0.05

* See the Board note at the end of this Section

benzene

0.001

77-47-4

Hexachlorocyclopentadiene

0.05

58-89-9

Lindane

0.0002

72-43-5

Methoxychlor

0.04

23135-22-0

Oxamyl (Vydate)

0.2

87-86-5

Pentachlorophenol

0.001

1918-02-1

Picloram

0.5

1336-36-3

Polychlorinated biphenyls (PCBs)

0.0005

122-34-9

Simazine

0.004

1746-01-6

2,3,7,8-TCDD (Dioxin)

0.00000003

8001-35-2

Toxaphene

0.003

93-72-1

2,4,5-TP

0.05

* See the Board note at the end of this Section.

2)         MCLs and HBWCs for PFAS apply to CWS and NTNCWS suppliers:

CAS Number

Contaminant

MCL (mg/ L)

HBWC (mg/l)

Not applicable

Hazard Index PFAS

(HFPO-DA, PFBS, PFHxS, and PFNA)

1 (unitless)

1

Not applicable

122499-17-6

HFPO-DA

0.00001

0.00001

45187-15-3

PFBS

No Individual MCL

0.002

108427-53-8

PFHxS

0.00001

0.00001

72007-68-2

PFNA

0.00001

0.00001

45285-51-6

PFOA

0.0000040

Not applicable

45298-90-6

PFOS

0.0000040

Not applicable

1

The PFAS Mixture

Hazard Index (HI) is the sum of component hazard quotients (HQs), which are

calculated by dividing the measured component PFAS concentration in water by

the relevant health-based water concentration when expressed in the same units

(shown in ng/l for simplification). The HBWC for PFHxS is 10 ng/l; the HBWC for

HFPO-DA is 10 ng/l; the HBWC for PFNA is 10 ng/l; and the HBWC for PFBS is 2000

ng/l.  A PFAS Mixture Hazard Index greater than 1 (unitless) indicates an

exceedance of the health protective level and indicates potential human health

risk from the PFAS mixture in drinking water.

Hazard Index = ([HFPO-DA

water

ng/l]/[10 ng/l]) + ([PFBS

water

ng/l]/[2000 ng/l]) + ([PFNA

water

ng/l]/[10 ng/l]) + ([PFHxS

water

ng/l]/[10 ng/l])

HBWC = health-based water

concentration

HQ = hazard quotient

ng/l = nanograms per liter

PFAS

water

= the concentration of a specific PFAS in water

d)         USEPA,

under section 1412 of SDWA identifies in Table 1 to subsection (d) the BAT,

treatment technique, or other means available for achieving compliance with the

maximum contaminant levels for all regulated PFAS identified in subsection (c)

C = health-based water

concentration

HQ = hazard quotient

ng/l = nanograms per liter

PFAS

water

= the concentration of a specific PFAS in water

d)         USEPA,

under section 1412 of SDWA identifies in Table 1 to subsection (d) the BAT,

treatment technique, or other means available for achieving compliance with the

maximum contaminant levels for all regulated PFAS identified in subsection (c).

Table 1 to Subsection (d) BAT for

PFAS Listed in Subsection (c)(2)

CAS No.

Contaminant

BAT

Not Applicable

Hazard Index PFAS

GAC, HPAE, RO, NF

122499-17-6

HFPO-DA

GAC, HPAE, RO, NF

108427-53-8

PHFxS

GAC, HPAE, RO, NF

72007-68-2

PFNA

GAC, HPAE, RO, NF

45285-51-6

PFOA

GAC, HPAE, RO, NF

45298-90-6

PFOS

GAC, HPAE, RO, NF

Abbreviations (BAT)

GAC

Granular Activated Carbon

HPAE

Anion Exchange

NF

Nanofiltration

PTA

Packed Tower Aeration

RO

Reverse Osmosis

e)         USEPA,

under section 1412 of SDWA, identifies in Table 1 to subsection (e) the

affordable technology, treatment technique, or other means available to

suppliers serving 10,000 persons or fewer for achieving compliance with the

MCLs for all regulated PFAS identified in subsection (c)(2)

Section 611.311(e) List of SSCTs

for PFAS.

Small System Compliance Technologies

1

Affordable for Listed Small System Categories

2

Anion Exchange

All size categories.

GAC

All size categories.

Reverse Osmosis,

3

Nanofiltration

3

3,301-10,000.

1

Section

1412(b)(4)(E)(ii) of SDWA specifies that small system compliance technologies

(SSCTs) must be affordable and technically feasible for small systems.

2

SDWA specifies three

categories of small systems: (i) those serving 25 or more, but fewer than 501,

mall System Categories

2

Anion Exchange

All size categories.

GAC

All size categories.

Reverse Osmosis,

3

Nanofiltration

3

3,301-10,000.

1

Section

1412(b)(4)(E)(ii) of SDWA specifies that small system compliance technologies

(SSCTs) must be affordable and technically feasible for small systems.

2

SDWA specifies three

categories of small systems: (i) those serving 25 or more, but fewer than 501,

(ii) those serving more than 500, but fewer than 3,301, and (iii) those serving

more than 3,300, but fewer than 10,001.

3

Technology rejects a

large volume of water and may not be appropriate for areas where water quantity

may be an issue.

BOARD NOTE:

This Section derives

from 40 CFR 141.61.

More stringent state MCLs for 2,4-D, heptachlor, and heptachlor epoxide appear

at Section 611.310.  In 40 CFR 141.6(g), USEPA postponed the effectiveness of

the MCLs for aldicarb, aldicarb sulfone, and aldicarb sulfoxide until it took

further action on those MCLs. See 40 CFR 141.6(g) and 57 Fed. Reg. 22178 (May

27, 1992).  USEPA later stated that it anticipated taking no action until 2005

on a federal national primary drinking water regulation (NPDWR) applicable to

the aldicarbs. 68 Fed. Reg. 31108 (May 27, 2003).  In 2005, USEPA indicated no

projected date for final action on the aldicarbs.

See

70 Fed. Reg.

27501, 671 (May 16, 2005). An entry for the aldicarbs last appeared in USEPA's

Spring 2007 semiannual regulatory agenda, indicating no projected dates for

further action.

See

72 Fed. Reg. 23156, 97 (Apr. 30, 2007);

see also

72 Fed. Reg. 70118, 23 (Dec. 10, 2007) (the first USEPA regulatory agenda that

included no entry for the aldicarbs).  As of early 2022, USEPA did not include

the aldicarbs among the NPDWRs on its webpage.  USEPA, Ground Water and

Drinking Water, National Primary Drinking Water Regulations

(www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations;

accessed February 16, 2022)

70118, 23 (Dec. 10, 2007) (the first USEPA regulatory agenda that

included no entry for the aldicarbs).  As of early 2022, USEPA did not include

the aldicarbs among the NPDWRs on its webpage.  USEPA, Ground Water and

Drinking Water, National Primary Drinking Water Regulations

(www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations;

accessed February 16, 2022).  While the Board must maintain entries for

aldicarb, aldicarb sulfoxide, and aldicarb sulfone to maintain consistency with

the literal text of the federal rules (

see

Sections 7.2 and 17.5 of the

Act; 42 U.S.C. 300g-2; 40 CFR 142.10), the Board intends that no aldicarb

requirements apply in Illinois until after USEPA adopts such requirements, and

the Board removes this statement.