Illinois Administrative Code › Title 35 - ENVIRONMENTAL PROTECTION › Part 611 - PRIMARY DRINKING WATER STANDARDS › Subpart N - INORGANIC MONITORING AND ANALYTICAL REQUIREMENTS › Section 611.600 - Applicability

Current through Register Vol. 48, No. 28, July 12, 2024
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)
0.0008
														5
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)
0.00005
														6
Atomic absorption - gaseous hydride technique
0.001
Inductively coupled plasma-mass spectrometry
0.0014
														7
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)
0.00002
														5
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)
0.0007
														5
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.
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.