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Water: CWA Methods

Approved General-Purpose Methods

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The analytical methods promulgated under the authority of Section 304(h) of the Clean Water Act are sometimes referred to as the "304(h)" or "Part 136" methods. The methods measure chemical and biological pollutants in media, such as wastewater, ambient water, sediment, and biosolids (sewage sludge). These various CWA methods are tested in a variety of labs and matrices. In addition to Part 136 methods, some approved methods are published or incorporated by reference at 40 CFR Parts 401-503, approved industry-specific methods.

CWA Methods of Interest Approved for use at 40 CFR 136
Number Method Title
120.1 Conductance, Specific Conductance (PDF) (3 pp, 14K)
130.1 Hardness, Total (mg/L as CaCO3), Colorimetric, Automated EDTA (PDF) (4 pp, 34K)
150.2 pH, Electrometric (Continuous Monitoring) (PDF) (4 pp, 18K)
160.4 Residue, Volatile, Gravimetric, Ignition at 550°C (PDF) (2 pp, 12K)
180.1 Determination of Turbidity by Nephelometry Revision 2.0 (PDF) (10 pp, 27K)
200.2 Sample Preparation Procedure for Spectrochemical Determination of Total Recoverable Elements Revision 2.8 (PDF) (12 pp, 38K)
200.5 Determination of Trace Elements in Drinking Water by Axially Viewed Inductively Coupled Plasma - Atomic Emission Spectrometry (PDF) (36 pp, 473K)
200.7 Determination of Metals and Trace Elements in Water and Wastes by Inductively Coupled Plasma-Atomic Emission Spectrometry Revision 4.4 (PDF) (58 pp, 223K)
200.8 Determination of Trace Elements in Water and Wastes by Inductively Coupled Plasma - Mass Spectrometry Revision 5.4 (PDF) (57 pp, 316K)
200.9 Determination of Trace Elements by Stabilized Temperature Graphite Furnace Atomic Absorption Spectrometry Revision 2.2 (PDF) (42 pp, 166K)
206.5 Arsenic, Sample Digestion Prior to Total Arsenic Analysis by Silver Diethyldithiocarbamate or Hydride Procedures (PDF) (2 pp, 11K)
218.6 Determination of Dissolved Hexavalent Chromium in Drinking Water, Groundwater, and Industrial Wastewater Effluents by Ion Chromatography Revision 3.3 (PDF) (10 pp, 33K)
231.2 Gold, Atomic Absorption, Furnace Technique (PDF) (2 pp, 12K)
235.2 Iridium, Atomic Absorption, Furnace Technique (PDF) (2 pp, 12K)
245.1 Determination of Mercury in Water by Cold Vapor Atomic Absorption Spectrometry Revision 3.0 (PDF) (18 pp, 119K)
245.2 Mercury, Cold Vapor Technique, Automated (PDF) (6 pp, 55K)
245.7 Mercury in Water by Cold Vapor Atomic Fluorescence Spectrometry Revision 2.0 (PDF) (33 pp, 195K)
252.2 Osmium, Atomic Absorption, Furnace Technique (PDF) (2 pp, 13K)
253.2 Palladium, Atomic Absorption, Furnace Technique (PDF) (2 pp, 13K)
255.2 Platinum, Atomic Absorption, Furnace Technique (PDF) (2 pp, 13K)
265.2 Rhodium, Atomic Absorption, Furnace Technique (PDF) (2 pp, 13K)
267.2 Ruthenium, Atomic Absorption, Furnace Technique (PDF) (2 pp, 13K)
279.2 Thallium, Atomic Absorption, Furnace Technique (PDF) (3 pp, 18K)
283.2 Titanium, Atomic Absorption, Furnace Technique (PDF) (2 pp, 13K)
289.2 Zinc, Atomic Absorption, Furnace Technique (PDF) (3 pp, 18K)
300.0 Determination of Inorganic Anions by Ion Chromatography Revision 2.1 (PDF) (28 pp, 74K)
300.1 Determination of Inorganic Anions in Drinking Water by Ion Chromatography Revision 1.0 (PDF) (40 pp, 398K)
310.2 Alkalinity, Colorimetric, Automated Methyl Orange (PDF) (4 pp, 28K)
335.4 Determination of Total Cyanide by Semi-Automated Colorimetry Revision 1.0 (PDF) (16 pp, 147K)
350.1 Determination of Ammonia Nitrogen by Semi-Automated Colorimetry Revision 2.0 (PDF) (15 pp, 180K)
351.1 Nitrogen, Kjeldahl, Total, Colorimetric, Automated Phenate (PDF) (7 pp, 83K)
351.2 Determination of Total Kjeldahl Nitrogen by Semi-Automated Colorimetry Revision 2.0 (PDF) (15 pp, 180K)
352.1 Nitrate, Colorimetric, Brucine (PDF) (4 pp, 18K)
353.2 Determination of Nitrate-Nitrite by Automated Colorimetry Revision 2.0 (PDF) (14 pp, 153K)
365.1 Determination of Phosphorus by Semi-Automated Colorimetry Revision 2.0 (PDF) (17 pp, 355K)
365.3 Phosphorus, All Forms, Colorimetric, Ascorbic Acid, Two Reagent (PDF) (4 pp, 17K)
365.4 Phosphorus, Total, Colorimetric, Automated, Block Digester, Automated Analyzer II (PDF) (5 pp, 58K)
375.2 Determination of Sulfate by Automated Colorimetry Revision 2.0 (PDF) (13 pp, 220K)
410.3 Chemical Oxygen Demand, Titrimetric, High-Level for Saline Waters (PDF) (3 pp, 26K)
410.4 Determination of Chemical Oxygen Demand by Semi-Automated Colorimetry Revision 2.0 (PDF) (12 pp, 139K)
420.1 Phenolics, Total Recoverable, Spectrophotometric, Manual 4-AAP With Distillation (PDF) (4 pp, 18K)
420.4 Determination of Total Recoverable Phenolics by Semi-Automated Colorimetry Revision 1.0 (PDF) (14 pp, 127K)
525.1 Determination of Organic Compounds in Drinking Water by Liquids-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry Revision 2.2 (PDF) (40 pp, 444K)
525.2 Methods for the Determination of Organic Compounds in Drinking Water (PDF) (62 pp, 160K)
601 Purgeable Halocarbons
602 Purgeable Aromatics
603 Acrolein and Acrylonitrile
604 Phenols
605 Benzidines
606 Phthalate Ester
607 Nitrosamines
608 Organochlorine Pesticides and PCBs
608.1 The Determination of Organochlorine Pesticides in Municipal and Industrial Wastewater (PDF) (20 pp, 81K)
608.2 The Determination of Certain Organochlorine Pesticides in Municipal and Industrial Wastewater (PDF) (18 pp, 79K)
609 Nitroaromatics and Isophorone
610 Polynuclear Aromatic Hydrocarbons
611 Haloethers
612 Chlorinated Hydrocarbons
613 2,3,7,8-Tetrachloro Dibenzo-p-Dioxin
614 The Determination of Organophosphorus Pesticides in Municipal and Industrial Wastewater (PDF) (20 pp, 82K)
614.1 The Determination of Organophosphorus Pesticides in Municipal and Industrial Wastewater (PDF) (17 pp, 74K)
615 The Determination of Chlorinated Herbicides in Municipal and Industrial Wastewater (PDF) (21 pp, 92K)
617 The Determination of Organohalide Pesticides and PCBs in Municipal and Industrial Wastewater (PDF) (32 pp, 195K)
619 The Determination of Triazine Pesticides in Municipal and Industrial Wastewater (PDF) (21 pp, 95K)
622 The Determination of Organophosphorus Pesticides in Municipal and Industrial Wastewater (PDF) (21 pp, 123K)
622.1 The Determination of Thiophosphate Pesticides in Municipal and Industrial Wastewater (PDF) (21 pp, 98K)
624 Purgeables
625 Base/Neutrals and Acids
632 The Determination of Carbamate and Urea Pesticides in Municipal and Industrial Wastewater (PDF) (19 pp, 85K)
900.0 Gross Alpha and Gross Beta Radioactivity in Drinking water (PDF) (9 pp, 53K)
903.0 Alpha-Emitting Radium Isotopes In Drinking Water (PDF) (7 pp, 31K)
903.1 Radium-226 in Drinking Water Radon Emanation Technique (PDF) (11 pp, 83K)
1000.0 Fathead Minnow, Pimephales promelas, Larval Survival and Growth Test Method (PDF) (page 48) (334 pp, 3.3MB)
1001.0 Fathead Minnow, Pimephales promelas, Embryo-larval Survival and Teratogenicity Test Method (PDF) (page 100) (334 pp, 3.3MB)
1002.0 Daphnid, Ceriodaphnia dubia, Survival and Reproduction Test Method (PDF) (page 128) (334 pp, 3.3MB)
1003.0 Green Alga, Selenastrum capricornutum, Growth Test Method (PDF) (page 181) (334 pp, 3.3MB)
1004.0 Sheepshead Minnow, Cryprinodon variegatus, Larval Survival and Growth Test Method (PDF) (page 53) (470 pp, 5.8MB)
1005.0 Sheepshead Minnow, Cryprinodon variegatus, Embryo-larval Survival and Teratogenicity Test Method (PDF) (page 110) (470 pp, 5.8MB)
1006.0 Inland Silverside, Menidia beryllina, Larval Survival and Growth Method (PDF) (page 146) (470 pp, 5.8MB)
1007.0 Mysid, Mysidopsis bahia, Survival, Growth, and Fecundity Test Method (PDF) (page 201) (470 pp, 5.8MB)
1008.0 Sea Urchin, Arbacia punctulata, Fertilization Test Method (PDF) (page 275) (470 pp, 5.8MB)
1103.1 Escherichia coli (E. coli) in Water by Membrane Filtration Using membrane-Thermotolerant Escherichia coli Agar (mTEC) 
1106.1 Enterococci in Water by Membrane Filtration Using membrane-Enterococcus-Esculin Iron Agar (mE-EIA) 
1600 Membrane Filter Test Method for Enterococci in Water 
1601 Male-specific (F+) and Somatic Coliphage in Water by Two-step Enrichment Procedure (PDF) (40 pp, 259K)
1602 Male-specific (F+) and Somatic Coliphage in Water by Single Agar Layer (SAL) Procedure (PDF) (38 pp, 207K)
1603 Escherichia coli (E. coli) in Water by Membrane Filtration Using Modified membrane-Thermotolerant Escherichia coli Agar (Modified mTEC)
1604 Total Coliforms and Escherichia coli in Water by MembraneFiltration Using a Simultaneous DetectionTechnique (MI Medium) (PDF) (18 pp, 384K)
1605 Aeromonas in Finished Water by Membrane Filtration using Ampicillin-Dextrin Agar withVancomycin (ADA-V) (PDF) (36 pp, 141K)
1613B Tetra-through Octa-Chlorinated Dioxins and Furans by Isotope Dilution High Resolution Gas Chromatography/High Resolution Mass Spectrometry Revision B
1622 Cryptosporidium in Water by Filtration/ Immunomagnetic Separation/Immunofluorescence Assay Microscopy
1623 Cryptosporidium and Giardia in Water by Filtration/IMS/FA
1624B Volatile Organic Compounds by Isotope Dilution Gas Chromatography-Mass Spectrometry Revision B
1625B Semivolatile Organic Compounds by Isotope Dilution Gas Chromatography-Mass Spectrometry Revision B
1627 Method 1627: Kinetic Test Method for the Prediction of Mine Drainage Quality (PDF) (37 pp, 650K) 
1631E Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence Spectrometry Revision E
1664A n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry Revision A
1664B Method 1664, Revision B: n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry (PDF) (35 pp, 495K)
OIA-1677 Available Cyanide by Flow Injection with Ligand Exchange
1680 Fecal Coliforms in Sewage Sludge (Biosolids) by Multiple-Tube Fermentation using Lauryl Tryptose Broth (LTB) and EC Medium
1681 Fecal Coliforms in Sewage Sludge (Biosolids) by Multiple-Tube Fermentation using A-1 medium
1682 Salmonella in Sewage Sludge (Biosolids) by Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium

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[1] There are several series of wastewater methods published under 40 CFR Part 136, including the 200 series, the 600 series, and the 1600 series. In addition to the wastewater methods, there are methods for other environmental media: the 300 series for air (MACT standards), the 500 series for drinking water, and the 8000 series for solid waste. ↩Back


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