Clean Water Act (CWA)
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.
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EPA Approved Methods for the Analysis of Multiple Metals in Wastewater
EPA Methods Approved for Conventional Pollutants in Wastewater
| Contaminant Group | Method | Instrumental Technique | Shimadzu Model |
|---|---|---|---|
| Cyanide | Standard Methods 4500 CN | Manual Spectrophotometry | UV-1900i Plus |
| Nitrate | Standard Methods 4500 NO3 | Manual Spectrophotometry | UV-1900i Plus |
| Nitrite | Standard Methods 4500 NO2 | Manual Spectrophotometry | UV-1900i Plus |
| Phosphate | Standard Methods 4500 P | Manual Spectrophotometry | UV-1900i Plus |
| Phenolics | EPA 420.1 | Manual Spectrophotometry | UV-1900i Plus |
| Sulfate | Standard Methods 4500 SO4 | Manual Spectrophotometry | UV-1900i Plus |
| Aggregate Organic Constituents | Standard Methods 5310B | Total Organic Carbon (TOC) | TOC-L |
EPA Approved Methods for Organics in Wastewater
| Contaminant Group | Method | Instrumental Technique | Shimadzu Model |
|---|---|---|---|
| Volatiles | EPA 624.1 | Purge & Trap GCMS (See Part 136.6 for allowed Flexibility) |
GCMS-QP2050 with EST |
| EPA 1624B | Purge & Trap isotope dilution GCMS | GCMS-QP2050 with EST | |
| Semi volatiles | EPA 625.1 | Liquid-Liquid Extraction Direct Injection GCMS | GCMS-QP2020 NX or GCMS-TQ8050 NX |
| EPA 1625B | Liquid-Liquid Extraction Direct Injection Isotope Dilution GCMS | GCMS-TQ8050 NX | |
| Dioxins | PAM-16130-SSI | GC-MS/MS | GCMS-TQ8050 NX |
| Organochlorine Pesticides and PCBs | EPA 608.3 | 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-2030 |
| PFAS | ASTM D8421 | LC-MS/MS | LCMS-8065XE |
| EPA 1633 | LC-MS/MS | LCMS-8065XE |
Other CWA Methods (not approved at 40 CFR Part 136)
| Contaminant Group | Method | Instrumental Technique | Shimadzu Model |
|---|---|---|---|
| Nitrosamines | ASTM D8456 | LC-MS/MS | LCMS-TQ RX Series |
| Organochlorine Pesticides and PCBs | ASTM D8543 | GC-MS/MS | GCMS-TQ8050 NX |
| Pesticides and Herbicides | ASTM D8574 | LC-MS/MS | LCMS-TQ RX Series |
| Total Nitrogen | ASTM D8083 | Total Organic Carbon Analysis (TOC) | TOC-L with TNM-L |
| Standard Methods 4500-N E | Total Organic Carbon Analysis (TOC) | TOC-L with TNM-L | |
| Total Nitrogen and Total Phosphorus | ASTM D8001 | Persulfate Digestion with Ion Chromatography | Nexera IC |