Applicability

Section 611 Section 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) 0.0008 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 MFL 1 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 plasma 2 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, spectrophotometric 3 0.02 Automated distillation, spectrophotometric 3 0.005 Distillation, selective electrode 3 0.05 Distillation, amenable, spectrophotometric 4 0.02 UV, distillation, spectrophotometric 8 0.0005 Micro distillation, flow injection, spectrophotometric 3 0.0006 Ligand exchange with amperometry 4 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) 0.0006 5 Inductively coupled plasma 2 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)) resulted 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.