Ill. Admin. Code tit. 35, § 611.600 - Applicability

Certain suppliers must monitor to determine compliance with the State-only MCLs in Section 611.300 and the revised MCLs in 611.301, as appropriate, as this Subpart N requires:

a) CWS suppliers.

b) NTNCWS suppliers.

c) Transient non-CWS suppliers to determine compliance with the nitrate and nitrite MCLs.

d) Detection Limits. Specific detection limits apply for this Subpart N (this list includes MCLs from Section 611.301 are for information purposes only):

Contaminant		MCL (mg/L, except asbestos)	Method	Detection Limit (mg/L)
Antimony		0.006	Atomic absorption - furnace technique	0.003
			Atomic absorption - furnace technique (stabilized temperature)	0.00085
			Inductively coupled plasma-mass spectrometry	0.0004
			Atomic absorption - gaseous hydride technique	0.001
Arsenic		0.010	Atomic absorption - furnace technique	0.001
			Atomic absorption - furnace technique (stabilized temperature)	0.000056
			Atomic absorption - gaseous hydride technique	0.001
			Inductively coupled plasma-mass spectrometry	0.00147
Asbestos		7 MFL1	Transmission electron microscopy	0.01 MFL
Barium		2	Atomic absorption - furnace technique	0.002
			Atomic absorption - direct aspiration technique	0.1
			Inductively coupled plasma arc furnace	0.002
			Inductively coupled plasma	0.001
Beryllium		0.004	Atomic absorption - furnace technique	0.0002
			Atomic absorption - furnace technique (stabilized temperature)	0.000025
			Inductively coupled plasma2	0.0003
			Inductively coupled plasma-mass spectrometry	0.0003
Cadmium		0.005	Atomic absorption - furnace technique	0.0001
			Inductively coupled plasma	0.001
Chromium		0.1	Atomic absorption - furnace technique	0.001
			Inductively coupled plasma	0.007
			Inductively coupled plasma	0.001
Cyanide		0.2	Distillation, spectrophotometric3	0.02
			Automated distillation, spectrophotometric3	0.005
			Distillation, selective electrode3	0.05
			Distillation, amenable, spectrophotometric4	0.02
			UV, distillation, spectrophotometric8	0.0005
			Micro distillation, flow injection, spectrophotometric3	0.0006
			Ligand exchange with amperometry4	0.0005
Mercury		0.002	Manual cold vapor technique	0.0002
			Automated cold vapor technique	0.0002
Nickel		No MCL	Atomic absorption - furnace technique	0.001
			Atomic absorption - furnace technique (stabilized temperature)	0.00065
			Inductively coupled plasma2	0.005
			Inductively coupled plasma-mass spectrometry	0.0005
Nitrate (as N)		10	Manual cadmium reduction	0.01
			Automated hydrazine reduction	0.01
			Automated cadmium reduction	0.05
			Ion-selective electrode	1
			Ion chromatography	0.01
			Capillary ion electrophoresis	0.076
Nitrite (as N)		1	Spectrophotometric	0.01
			Automated cadmium reduction	0.05
			Manual cadmium reduction	0.01
			Ion chromatography	0.004
			Capillary ion electrophoresis	0.103
Selenium		0.05	Atomic absorption - furnace technique	0.002
			Atomic absorption - gaseous hydride technique	0.002
Thallium		0.002	Atomic absorption - furnace technique	0.001
			Atomic absorption - furnace technique (stabilized temperature)	0.00075
			Inductively coupled plasma-mass spectrometry	0.0003
Footnotes.
1	"MFL" means millions of fibers per liter less than 10 µm.
2	Using a 2x preconcentration step as noted in USEPA 200.7(94). Lower MDLs are possible when using a 4x preconcentration.
3	Screening method for total cyanides.
4	Measures "free" cyanides when omitting distillation, digestion, or ligand exchange.
5	Lower MDLs are possible using stabilized temperature graphite furnace atomic absorption.
6	The MDL for USEPA 200.9(94) (atomic absorption-platform furnace (stabilized temperature)) possible using a 2x concentration step during sample digestion. The MDL using direct analyses (i.e., no sample digestion) is higher. Using multiple depositions, USEPA 200.9(94) can obtain an MDL of 0.0001 mg/L.
7	Using selective ion monitoring, USEPA 200.8(94) (ICP-MS) is capable of obtaining an MDL of 0.0001 mg/L.
8	Measures total cyanides when using UV-digestor, and "free" cyanides when bypassing UV-digestor.

Notes

Ill. Admin. Code tit. 35, § 611.600

Amended at 37 Ill. Reg. 1978, effective February 4, 2013

Amended at 39 Ill. Reg. 3713, effective 2/24/2015 Amended at 42 Ill. Reg. 1140, effective 1/4/2018 Amended at 44 Ill. Reg. 6996, effective 4/17/2020 Amended at 47 Ill. Reg. 16486, effective 11/2/2023

BOARD NOTE: Subsections (a) through (c) derive from 40 CFR 141.23 preamble, and subsection (d) derives from 40 CFR 141.23 (a)(4)(i) and appendix A to subpart C of 40 CFR 141 . See the Board Note at Section 611.301(b) relating to the MCL for nickel.