Ill. Admin. Code tit. 35, § 620.420 - Groundwater Quality Standards for Class II: General Resource Groundwater

Current through Vol. 46, No. 16, April 15, 2022

a) Inorganic Chemical Constituents
1) Except due to natural causes or as provided in Section 620.450 or subsection (a)(3) or (e) of this Section, concentrations of the following chemical constituents must not be exceeded in Class II groundwater:

Constituent

Standard

(mg/L)

Antimony

0.024

Arsenic*

0.2

Barium

2.0

Beryllium

0.5

Cadmium

0.05

Chromium

1.0

Cobalt

1.0

Cyanide

0.6

Fluoride

4.0

Lead

0.1

Mercury

0.01

Nitrate as N

100.0

Perchlorate

0.0049

Thallium

0.02

Vanadium

0.1

*Denotes a carcinogen.

2) Except as provided in Section 620.450 or subsection (a)(3) or (e) of this Section, concentrations of the following chemical constituents must not be exceeded in Class II groundwater:

Constituent

Standard

(mg/L)

Boron

2.0

Chloride

200.0

Copper

0.65

Iron

5.0

Manganese

10.0

Nickel

2.0

Selenium

0.05

Total Dissolved Solids

(TDS)

1,200.0

Sulfate

400.0

Zinc

10.0

3) The standard for any inorganic chemical constituent listed in subsection (a)(2) of this Section, for barium, or for pH does not apply to groundwater within fill material or within the upper 10 feet of parent material under such fill material on a site not within the rural property class for which:
A) Prior to November 25, 1991, surficial characteristics have been altered by the placement of such fill material so as to impact the concentration of the parameters listed in subsection (a)(3) of this Section, and any on-site groundwater monitoring of such parameters is available for review by the Agency.
B) On November 25, 1991, surficial characteristics are in the process of being altered by the placement of such fill material, that proceeds in a reasonably continuous manner to completion, so as to impact the concentration of the parameters listed in subsection (a)(3) of this Section, and any on-site groundwater monitoring of such parameters is available for review by the Agency.
4) For purposes of subsection (a)(3) of this Section, the term "fill material" means clean earthen materials, slag, ash, clean demolition debris, or other similar materials.
b) Organic Chemical Constituents
1) Except due to natural causes or as provided in Section 620.450 or subsection (b)(2) or (e) of this Section, concentrations of the following organic chemical constituents must not be exceeded in Class II groundwater:

Constituent

Standard

(mg/L)

Acenaphthene

2.1

Acetone

6.3

Alachlor*

0.010

Aldicarb

0.015

Anthracene

10.5

Atrazine

0.015

Benzene*

0.025

Benzo(a)anthracene*

0.00065

Benzo(b)fluoranthene*

0.0009

Benzo(k)fluoranthene*

0.006

Benzo(a)pyrene*

0.002

Benzoic acid

28.0

2-Butanone (MEK)

4.2

Carbon Disulfide

3.5

Carbofuran

0.2

Carbon Tetrachloride*

0.025

Chlordane*

0.01

Chloroform*

0.35

Chrysene*

0.06

Dalapon

2.0

Dibenzo(a,h)anthracene*

0.0015

Dicamba

0.21

Dichlorodifluoromethane

7.0

1,1-Dichloroethane

7.0

Dichloromethane*

0.05

Di(2-ethylhexyl)phthalate*

0.06

Diethyl Phthalate

5.6

Di-n-butyl Phthalate

3.5

Dinoseb

0.07

Endothall

0.1

Endrin

0.01

Ethylene Dibromide*

0.0005

Fluoranthene

1.4

Fluorene

1.4

Heptachlor*

0.002

Heptachlor Epoxide*

0.001

Hexachlorocyclopentadiene

0.5

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

0.0022

Isopropylbenzene (Cumene)

3.5

Lindane (Gamma-Hexachloro cyclophexane)

0.001

2,4-D

0.35

Ortho-Dichlorobenze

1.5

Para-Dichlorobenzene

0.375

1,2-Dibromo-3-Chloropropane*

0.002

1,2-Dichloroethane*

0.025

1,1-Dichloroethylene

0.035

cis-1,2-Dichloroethylene

0.2

Trans-1,2-Dichloroethylene

0.5

1,2-Dichloropropane*

0.025

Ehylbenzene

1.0

MCPP (Mecoprop)

0.007

Methoxychlor

0.2

2-Methylnaphthalene

0.14

2-Methylphenol

0.35

Methyl Tertiary-Butyl Ether (MTBE)

0.07

Monochlorobenzene

0.5

Naphthalene

0.22

P-Dioxane*

0.0077

Pentachlorophenol*

0.005

Phenols

0.1

Picloram

5.0

Pyrene

1.05

Polychlorinated Biphenyls (PCBs) (as decachloro-biphenyl)*

0.0025

alpha-BHC (alpha-Benzene

hexachloride)*

0.00055

Simazine

0.04

Styrene

0.5

2,4,5-TP

0.25

Tetrachloroethylene*

0.025

Toluene

2.5

Toxaphene*

0.015

1,1,1-Trichloroethane

1.0

1,2,4-Trichlorobenzene

0.7

1,1,2-Trichloroethane

0.05

Trichloroethylene*

0.025

Trichlorofluoromethane

10.5

Vinyl Chloride*

0.01

Xylenes

10.0

* Denotes a carcinogen.

2) The standards for pesticide chemical constituents listed in subsection (b)(1) of this Section do not apply to groundwater within 10 feet of the land surface, provided that the concentrations of such constituents result from the application of pesticides in a manner consistent with the requirements of the Federal Insecticide, Fungicide and Rodenticide Act ( 7 USC 136 et seq.) and the Illinois Pesticide Act [415 ILCS 60 ].
c) Explosive Constituents

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

Constituent

Standard

(mg/L)

Benzene*

0.025

BETX

13.525

*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 II groundwater that is within 5 feet of the land surface.

Notes

Ill. Admin. Code tit. 35, § 620.420

Amended at 37 Ill. Reg. 16529, effective October 7, 2013

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