Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 620 - GROUNDWATER QUALITY
Subpart D - GROUNDWATER QUALITY STANDARDS
Section 620.410 - Groundwater Quality Standards for Class I: Potable Resource Groundwater

Universal Citation: 35 IL Admin Code ยง 620.410

Current through Register Vol. 48, No. 38, September 20, 2024

a) Inorganic Chemical Constituents

Except due to natural causes or as provided in Section 620.450, concentrations of the following chemical constituents must not be exceeded in Class I groundwater:

Constituent

Units

Standard

Antimony

mg/L

0.006

Arsenic*

mg/L

0.010

Barium

mg/L

2.0

Beryllium

mg/L

0.004

Boron

mg/L

2.0

Cadmium

mg/L

0.005

Chloride

mg/L

200.0

Chromium

mg/L

0.1

Cobalt

mg/L

1.0

Copper

mg/L

0.65

Cyanide

mg/L

0.2

Fluoride

mg/L

4.0

Iron

mg/L

5.0

Lead

mg/L

0.0075

Manganese

mg/L

0.15

Mercury

mg/L

0.002

Nickel

mg/L

0.1

Nitrate as N

mg/L

10.0

Perchlorate

mg/L

0.0049

Radium-226

pCi/l

20.0

Radium-228

pCi/l

20.0

Selenium

mg/L

0.05

Silver

mg/L

0.05

Sulfate

mg/L

400.0

Thallium

mg/L

0.002

Total Dissolved

Solids (TDS)

mg/L

1,200

Vanadium

mg/L

0.049

Zinc

mg/L

5.0

*Denotes a carcinogen.

b) Organic Chemical Constituents

Except due to natural causes or as provided in Section 620.450 or subsection (d), concentrations of the following organic chemical constituents shall not be exceeded in Class I groundwater:

Constituent

Standard (mg/L)

Acenaphthene

0.42

Acetone

6.3

Alachlor*

0.002

Aldicarb

0.003

Anthracene

2.1

Atrazine

0.003

Benzene*

0.005

Benzo(a)anthracene*

0.00013

Benzo(b)fluoranthene*

0.00018

Benzo(k)fluoranthene*

0.00017

Benzo(a)pyrene*

0.0002

Benzoic acid

28.0

2-Butanone (MEK)

4.2

Carbofuran

0.04

Carbon Disulfide

0.7

Carbon Tetrachloride*

0.005

Chlordane*

0.002

Chloroform*

0.07

Chrysene*

0.012

Dalapon

0.2

Dibenzo(a,h)anthracene*

0.0003

Dicamba

0.21

Dichlorodifluoromethane

1.4

1,1-Dichloroethane

1.4

Dichloromethane*

0.005

Di(2-ethylhexyl)phthalate*

0.006

Diethyl Phthalate

5.6

Di-n-butyl Phthalate

0.7

Dinoseb

0.007

Endothall

0.1

Endrin

0.002

Ethylene Dibromide*

0.00005

Fluoranthene

0.28

Fluorene

0.28

Heptachlor*

0.0004

Heptachlor Epoxide*

0.0002

Hexachlorocyclopentadiene

0.05

Indeno(1,2,3-cd)pyrene*

0.00043

Isopropylbenzene (Cumene)

0.7

Lindane (Gamma-Hexachlorocyclohexane)

0.0002

2,4-D

0.07

ortho-Dichlorobenzene

0.6

para-Dichlorobenzene

0.075

1,2-Dibromo-3-Chloropropane*

0.0002

1,2-Dichloroethane*

0.005

1,1-Dichloroethylene

0.007

cis-1,2-Dichloroethylene

0.07

trans-1,2-Dichloroethylene

0.1

1,2-Dichloropropane*

0.005

Ethylbenzene

0.7

MCPP (Mecoprop)

0.007

Methoxychlor

0.04

2-Methylnaphthalene

0.028

2-Methylphenol

0.35

Methyl Tertiary-Butyl Ether (MTBE)

0.07

Monochlorobenzene

0.1

Naphthalene

0.14

P-Dioxane*

0.0077

Pentachlorophenol*

0.001

Phenols

0.1

Picloram

0.5

Pyrene

0.21

Polychlorinated

Biphenyls (PCBs)

(as decachloro-biphenyl)*

0.0005

alpha-BHC (alpha-Benzene hexachloride)*

0.00011

Simazine

0.004

Styrene

0.1

2,4,5-TP (Silvex)

0.05

Tetrachloroethylene*

0.005

Toluene

1.0

Toxaphene*

0.003

1,1,1-Trichloroethane

0.2

1,1,2-Trichloroethane

0.005

1,2,4-Trichlorobenzene

0.07

Trichloroethylene*

0.005

Trichlorofluoromethane

2.1

Vinyl Chloride*

0.002

Xylenes

10.0

*Denotes a carcinogen.

c) Explosive Constituents

Concentrations of the following explosive constituents must not exceed the Class I groundwater standard:

Constituent

Standard (mg/L)

1,3-Dinitrobenzene

0.0007

2,4-Dinitrotoluene*

0.0001

2,6-Dinitrotoluene*

0.00031

HMX (High Melting

Explosive, Octogen)

1.4

Nitrobenzene

0.014

RDX (Royal Demolition

Explosive, Cyclonite)

0.084

1,3,5-Trinitrobenzene

0.84

2,4,6-Trinitrotoluene (TNT)

0.014

*Denotes a carcinogen.

d) Complex Organic Chemical Mixtures

Concentrations of the following chemical constituents of gasoline, diesel fuel, or heating fuel must not be exceeded in Class I groundwater:

Constituent

Standard (mg/L)

Benzene*

0.005

BETX

11.705

*Denotes a carcinogen.

e) pH

Except due to natural causes, a pH range of 6.5 - 9.0 units must not be exceeded in Class I groundwater.

f) Beta Particle and Photon Radioactivity

1) Except due to natural causes, the average annual concentration of beta particle and photon radioactivity from man-made radionuclides shall not exceed a dose equivalent to the total body organ greater than 4 mrem/year in Class I groundwater. If two or more radionuclides are present, the sum of their dose equivalent to the total body, or to any internal organ shall not exceed 4 mrem/year in Class I groundwater except due to natural causes.

2) Except for the radionuclides listed in subsection (f)(3), the concentration of man-made radionuclides causing 4 mrem total body or organ dose equivalent must be calculated on the basis of a 2 liter per day drinking water intake using the 168-hour data in accordance with the procedure set forth in NCRP Report Number 22, incorporated by reference at Section 620.125(a).

3) Except due to natural causes, the average annual concentration assumed to produce a total body or organ dose of 4 mrem/year of the following chemical constituents shall not be exceeded in Class I groundwater:

Critical

Standard

Constituent

Organ

(pCi/L)

Tritium

Total body

20,000.0

Strontium-90

Bone marrow

8.0

Disclaimer: These regulations may not be the most recent version. Illinois may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.