The Clean Water Act (CWA) regulates discharge of pollutants into the waters of the United States and regulates water quality standards for surface water.

Under the CWA it is unlawful to discharge any pollutant from a point source into navigable waters without a permit. The National Pollutant Discharge Elimination System (NPDES) issues permits to industrial, municipal, and other facilities that discharge directly to surface waters.

EPA publishes laboratory analytical methods, or test procedures, that must be used by industries and municipalities to analyze regulated pollutants in wastewater and other environmental samples. Most of these methods are published as regulations in the Code of Federal Regulations (CFR) at Title 40 Part 136.


​EPA Approved Methods for the Analysis of Multiple Metals in Waste Water

Method Instrumental Technique Shimadzu Model
EPA 200.5 ICP Axial ICPE-9800
EPA 200.7 ICP Radial
Axial allowed at Part 136.6
EPA 200.8 ICPMS Collision cells allowed at Part 136.6 ICPMS-2030
EPA 200.9 GFAAS AA-7000G


EPA approved Methods for Anions and in Waste Water

Anions Method Instrumental Technique Shimadzu Model
Cyanide Standard Methods 4500 CN Manual Spectrophotometry UV-1280
Nitrate Standard Methods 4500 NO3 Manual Spectrophotometry UV-1280
Nitrite Standard Methods 4500 NO2 Manual Spectrophotometry UV-1280
Phosphate Standard Methods 4500 P Manual Spectrophotometry UV-1280
Phenolics EPA 420.1 Manual Spectrophotometry UV-1280
Sulfate Standard Methods 4500 SO4 Manual Spectrophotometry UV-1280


EPA Approved Methods for Organics in Waste Water

Contaminant Group Method Instrumental Technique Shimadzu Model
Volatiles EPA 624 Purge & Trap GCMS
(See Part 136.6 for allowed Flexibility)
GCMS-QP2010SE with EST
EPA 1624B Purge & Trap isotope dilution GCMS GCMS-QP2010SE with EST
Semi volatiles EPA 625 Liquid-Liquid Extraction Direct Injection GCMS GCMS-QP2010SE or GCMS-QP2020
EPA 1625B Liquid-Liquid Extraction Direct Injection Isotope Dilution GCMS GCMS-QP2010SE or GCMS-QP2020
Dioxins EPA 1613
Solvent Extraction direct injection HRGC/HRMS GCMS-TQ8040
Screening only not for compliance testing
Organochlorine Pesticides and PCBs EPA 608 Liquid-Liquid Extraction Direct Injection GC with ECD GC-2030
Organophosphorus and organonitrogen pesticides EPA 507 Liquid-Liquid Extraction Direct Injection GC with NPD GC-2030
Organophosphorus Pesticides EPA 614 Liquid-Liquid Extraction Direct Injection GC with FPD GC-2030
EPA 622 Liquid-Liquid Extraction Direct Injection GC with NPD GC-2030
Triazine pesticides EPA 619 Liquid-Liquid Extraction Direct Injection GC with NPD GC-2030
Chlorinated Acids (Herbicides) EPA 615 Liquid-Liquid Extraction, Derivatization and GC with ECD GC-2010 Plus with ECD


Contaminant of Concern Method Shimadzu Instrument
Total Organic Carbon (TOC) Standard Methods 5310B TOC-L


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