{"query":{"parameter":"silver","place":"US-CA","medium":null,"statistic":null,"kind":null},"searched":{"places":["US-CA","US"],"parameter_keys":["cas:7440-22-4","cas:93-72-1","cas:506-61-6","name:silver-108m","name:silver-110m","name:silver-111","cas:506-64-9","name:silver - total","name:silver, total","name:silver, total recoverable","name:total silver"],"names_matched":[["silver","cas:7440-22-4"],["2 4 5 tp silver","cas:93-72-1"],["potassium silver cyanide","cas:506-61-6"],["silver 108m","name:silver-108m"],["silver 110m","name:silver-110m"],["silver 111","name:silver-111"],["silver cyanide","cas:506-64-9"],["silver cyanide ag cn","cas:506-64-9"],["silver total","name:silver - total"],["silver total","name:silver, total"],["silver total recoverable","name:silver, total recoverable"],["total silver","name:total silver"],["total silver freshwater","name:total silver"],["total silver marine","name:total silver"],["plata total","name:total silver","plata"]],"match":"exact+contains","order":"The place's own instruments first, then each place above it, each in its register's order","not_sent":{"rows":9,"names":["Trichlorophenoxypropionic acid, -2,4,5","Chlorophenoxy Herbicide (2,4,5-TP) [Silvex]","2,4,5-TP (Silvex)"],"says":"9 rows share a parameter key with a longer name holding \"silver\" but are printed under names without these words (that key is wider than the name): not sent. Ask for one by its name or CAS number."}},"total":451,"offset":0,"returned":50,"next_offset":50,"rows":[{"id":"099a0eae8fbb95f0","parameter":"Silver","value":"3.4 e,i,m","value_num":3.4,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["receiving_water is freshwater","inland surface waters and enclosed bays and estuaries of California (not ocean waters, which the Ocean Plan covers) (40 CFR 131.38(a), (d)(1))","freshwater criteria: waters whose salinity is 1 part per thousand or less 95% or more of the time; between 1 and 10 ppt the more stringent of the freshwater and saltwater criteria applies (40 CFR 131.38(c)(3))","hardness 100 mg/L as CaCO3 (note e: the value displayed corresponds to a total hardness of 100 mg/L; other hardness takes the equations of 40 CFR 131.38(b)(2))"],"cite":{"instrument":"us_ca_ctr","title":"California Toxics Rule, 40 CFR 131.38: numeric criteria for priority toxic pollutants for California's inland surface waters and enclosed bays and estuaries (freshwater and saltwater CMC/CCC, human health)","issuer":"US Environmental Protection Agency (promulgated for the State of California)","edition":"40 CFR 131.38(b)(1) Table 1 as republished in full by the final rule 'Water Quality Standards; Establishment of a Numeric Criterion for Selenium for the State of California' (89 FR 101914, December 17, 2024), the table eCFR serves today (as images); paragraphs (c)-(d) from eCFR as of 2026-10-01","source_url":"https://www.govinfo.gov/content/pkg/FR-2024-12-17/pdf/2024-29483.pdf","source_sha256":"563001982d0d74d96f6eb7222df4c125bf5e9809c77ab2f84ff948a3b87edfe2","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 131.38(b)(1) Table 1","page":16,"quote":"11. Silver b 7440224 3.4 e,i,m 1.9 i,m","transcription":"OCR text layer of a printed table image (Federal Register); the image itself is the authority"}},{"id":"389aa6c759c1c970","parameter":"Silver","value":"1.9 i,m","value_num":1.9,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["receiving_water is marine","inland surface waters and enclosed bays and estuaries of California (not ocean waters, which the Ocean Plan covers) (40 CFR 131.38(a), (d)(1))","saltwater criteria: waters whose salinity is 10 parts per thousand or more 95% or more of the time; between 1 and 10 ppt the more stringent of the freshwater and saltwater criteria applies (40 CFR 131.38(c)(3))"],"cite":{"instrument":"us_ca_ctr","title":"California Toxics Rule, 40 CFR 131.38: numeric criteria for priority toxic pollutants for California's inland surface waters and enclosed bays and estuaries (freshwater and saltwater CMC/CCC, human health)","issuer":"US Environmental Protection Agency (promulgated for the State of California)","edition":"40 CFR 131.38(b)(1) Table 1 as republished in full by the final rule 'Water Quality Standards; Establishment of a Numeric Criterion for Selenium for the State of California' (89 FR 101914, December 17, 2024), the table eCFR serves today (as images); paragraphs (c)-(d) from eCFR as of 2026-10-01","source_url":"https://www.govinfo.gov/content/pkg/FR-2024-12-17/pdf/2024-29483.pdf","source_sha256":"563001982d0d74d96f6eb7222df4c125bf5e9809c77ab2f84ff948a3b87edfe2","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 131.38(b)(1) Table 1","page":16,"quote":"11. Silver b 7440224 3.4 e,i,m 1.9 i,m","transcription":"OCR text layer of a printed table image (Federal Register); the image itself is the authority"}},{"id":"a5cce581e47e514d","parameter":"Silver","value":"7.0E-01","value_num":0.7,"unit":"µg/L","direction":"max","kind":"guideline","medium":"groundwater","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["Tier 1 ESLs: one level per chemical and medium for a generic site (residential land use, groundwater a drinking-water resource, shallow soil); a screening level is not a cleanup standard"],"cite":{"instrument":"us_ca_esl_groundwater","title":"California, San Francisco Bay RWQCB — Environmental Screening Levels (ESLs), Tier 1, 2025 (Rev. 4) — groundwater","issuer":"San Francisco Bay Regional Water Quality Control Board","edition":"2025 (Rev. 4)","source_url":"https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/ESL_Summary_Tables_Rev4.pdf","source_sha256":null,"fetched_at":"2026-09-30","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":null,"page":null,"quote":null,"table":"eau","column":"tier1"}},{"id":"5fb24a027c3fe0d4","parameter":"Silver","value":"2.5E+01","value_num":25,"unit":"mg/kg","direction":"max","kind":"guideline","medium":"soil","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["Tier 1 ESLs: one level per chemical and medium for a generic site (residential land use, groundwater a drinking-water resource, shallow soil); a screening level is not a cleanup standard"],"cite":{"instrument":"us_ca_esl_soil","title":"California, San Francisco Bay RWQCB — Environmental Screening Levels (ESLs), Tier 1, 2025 (Rev. 4) — soil","issuer":"San Francisco Bay Regional Water Quality Control Board","edition":"2025 (Rev. 4)","source_url":"https://www.waterboards.ca.gov/sanfranciscobay/water_issues/programs/ESL/ESL_Summary_Tables_Rev4.pdf","source_sha256":null,"fetched_at":"2026-09-30","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":null,"page":null,"quote":null,"table":"sols","column":"tier1"}},{"id":"4f01b3bc6845ecce","parameter":"Silver","value":"0.7","value_num":0.7,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["receiving_water is marine","ocean waters of California (the territorial sea and the waters beyond the enclosed bays, estuaries and coastal lagoons): the Ocean Plan's jurisdiction","in the receiving water upon completion of initial dilution (chapter III.C.3)"],"cite":{"instrument":"us_ca_ocean_plan","title":"Water Quality Control Plan for Ocean Waters of California (California Ocean Plan, 2019): Table 3 water quality objectives, Table 4 effluent limitations, and the salinity limitation for desalination brine","issuer":"State of California, State Water Resources Control Board","edition":"California Ocean Plan 2019, effective February 4, 2019 (State Water Resources Control Board; includes the 2015 desalination amendment, effective January 28, 2016), as the State Water Board serves it 2026-10-14","source_url":"https://www.waterboards.ca.gov/water_issues/programs/ocean/docs/oceanplan2019.pdf","source_sha256":"cbff9eaf5b7df1c9b818190851d4196e26c53b56b1860ce11fc44bdf125a5d6c","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Ocean Plan chapter II.D, Table 3, objectives for protection of marine aquatic life","page":17,"quote":null}},{"id":"7a5cf302a77c5e88","parameter":"Silver","value":"2.8","value_num":2.8,"unit":"µg/L","statistic":"daily_max","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["receiving_water is marine","ocean waters of California (the territorial sea and the waters beyond the enclosed bays, estuaries and coastal lagoons): the Ocean Plan's jurisdiction","in the receiving water upon completion of initial dilution (chapter III.C.3)"],"cite":{"instrument":"us_ca_ocean_plan","title":"Water Quality Control Plan for Ocean Waters of California (California Ocean Plan, 2019): Table 3 water quality objectives, Table 4 effluent limitations, and the salinity limitation for desalination brine","issuer":"State of California, State Water Resources Control Board","edition":"California Ocean Plan 2019, effective February 4, 2019 (State Water Resources Control Board; includes the 2015 desalination amendment, effective January 28, 2016), as the State Water Board serves it 2026-10-14","source_url":"https://www.waterboards.ca.gov/water_issues/programs/ocean/docs/oceanplan2019.pdf","source_sha256":"cbff9eaf5b7df1c9b818190851d4196e26c53b56b1860ce11fc44bdf125a5d6c","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Ocean Plan chapter II.D, Table 3, objectives for protection of marine aquatic life","page":17,"quote":null}},{"id":"2abf9e571cbeb6af","parameter":"Silver","value":"7.","value_num":7,"unit":"µg/L","statistic":"instant","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"cas:7440-22-4","place":["US-CA"],"conditions":["receiving_water is marine","ocean waters of California (the territorial sea and the waters beyond the enclosed bays, estuaries and coastal lagoons): the Ocean Plan's jurisdiction","in the receiving water upon completion of initial dilution (chapter III.C.3)"],"cite":{"instrument":"us_ca_ocean_plan","title":"Water Quality Control Plan for Ocean Waters of California (California Ocean Plan, 2019): Table 3 water quality objectives, Table 4 effluent limitations, and the salinity limitation for desalination brine","issuer":"State of California, State Water Resources Control Board","edition":"California Ocean Plan 2019, effective February 4, 2019 (State Water Resources Control Board; includes the 2015 desalination amendment, effective January 28, 2016), as the State Water Board serves it 2026-10-14","source_url":"https://www.waterboards.ca.gov/water_issues/programs/ocean/docs/oceanplan2019.pdf","source_sha256":"cbff9eaf5b7df1c9b818190851d4196e26c53b56b1860ce11fc44bdf125a5d6c","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Ocean Plan chapter II.D, Table 3, objectives for protection of marine aquatic life","page":17,"quote":null}},{"id":"fc3a9e37c51807d0","parameter":"Silver","value":"5.0","value_num":5,"unit":"mg/L","direction":"max","kind":"threshold","medium":"leachate","level":"national","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["(a) A solid waste (except manufactured gas plant waste) exhibits the characteristic of toxicity if, using the Toxicity Characteristic Leaching Procedure, test Method 1311 in “Test Methods for Evaluating Solid Waste, Physical/Chemical Methods,” EPA Publication SW-846, as incorporated by reference in § 260.11 of this chapter, the extract from a representative sample of the waste contains any of the contaminants listed in table 1 at the concentration equal to or greater than the respective value given in that table. Where the waste contains less than 0.5 percent filterable solids, the waste itself, after filtering using the methodology outlined in Method 1311, is considered to be the extract for the purpose of this section."],"cite":{"instrument":"us_40cfr261_24","title":"40 CFR 261.24 — Toxicity characteristic: Table 1, maximum concentration of contaminants for the toxicity characteristic (TCLP regulatory levels)","issuer":"U.S. Environmental Protection Agency (EPA)","edition":"eCFR, 40 CFR 261.24 as of 2026-10-13 (title 40 up to date as of that day)","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-13/title-40.xml?part=261&section=261.24","source_sha256":"3a1ec9b0d3051c70e471e359275657b0fa6d98e80927d2217e82b2dbbca60961","fetched_at":"2026-10-15","section":"40 CFR 261.24, Table 1","page":null,"quote":"D011 Silver 7440-22-4 5.0"}},{"id":"d59ca9cffa240308","parameter":"Ag","value":"1.2","value_num":1.2,"unit":"mg/L","statistic":"daily_max","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"sewer","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is sewer","cites is 40 CFR 413","the discharge is of the Subpart B—Electroplating of Precious Metals Subcategory","existing sources (PSES)","(c) For plants discharging 38,000 liters (10,000 gal) or more per calendar day of electroplating process wastewater the following limitations shall apply:","table: Subpart B—Precious Metals Facilities Discharging 38,000 Liters or More Per Day PSES Limitations (mg/l)"],"cite":{"instrument":"us_40cfr413","title":"40 CFR Part 413 — PART 413—ELECTROPLATING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 2026-10-05","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-05/title-40.xml?part=413","source_sha256":"9c6c38baf048e0e1ed5f2c05df397ea581d48822b23c4b294e52b960b2d547f9","fetched_at":"2026-10-09","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 413.24 (PSES)","page":null,"quote":"Ag 1.2 0.7"}},{"id":"16d95930ac34512e","parameter":"Ag","value":"0.7","value_num":0.7,"unit":"mg/L","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"sewer","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is sewer","cites is 40 CFR 413","the discharge is of the Subpart B—Electroplating of Precious Metals Subcategory","existing sources (PSES)","(c) For plants discharging 38,000 liters (10,000 gal) or more per calendar day of electroplating process wastewater the following limitations shall apply:","table: Subpart B—Precious Metals Facilities Discharging 38,000 Liters or More Per Day PSES Limitations (mg/l)"],"cite":{"instrument":"us_40cfr413","title":"40 CFR Part 413 — PART 413—ELECTROPLATING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 2026-10-05","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-05/title-40.xml?part=413","source_sha256":"9c6c38baf048e0e1ed5f2c05df397ea581d48822b23c4b294e52b960b2d547f9","fetched_at":"2026-10-09","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 413.24 (PSES)","page":null,"quote":"Ag 1.2 0.7"}},{"id":"fa9ff27d054253b2","parameter":"Ag","value":"47","value_num":47,"unit":"mg/sq m-Operation","statistic":"daily_max","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"sewer","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is sewer","cites is 40 CFR 413","the discharge is of the Subpart B—Electroplating of Precious Metals Subcategory","existing sources (PSES)","(d) Alternatively, the following mass-based standards are equivalent to and may apply in place of those limitations specified under paragraph (c) of this section upon prior agreement between a source subject to these standards and the publicly owned treatment works receiving such regulated wastes:","table: Subpart B—Precious Metals Facilities Discharging 38,000 Liters or More Per Day PSES Limitations (mg/sq m-Operation)"],"cite":{"instrument":"us_40cfr413","title":"40 CFR Part 413 — PART 413—ELECTROPLATING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 2026-10-05","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-05/title-40.xml?part=413","source_sha256":"9c6c38baf048e0e1ed5f2c05df397ea581d48822b23c4b294e52b960b2d547f9","fetched_at":"2026-10-09","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 413.24 (PSES)","page":null,"quote":"Ag 47 29"}},{"id":"dff57f98eaf0a460","parameter":"Ag","value":"29","value_num":29,"unit":"mg/sq 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2026-10-05","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-05/title-40.xml?part=413","source_sha256":"9c6c38baf048e0e1ed5f2c05df397ea581d48822b23c4b294e52b960b2d547f9","fetched_at":"2026-10-09","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 413.24 (PSES)","page":null,"quote":"Ag 47 29"}},{"id":"531e7c287de9c099","parameter":"Silver","value":"0.0090","value_num":0.009,"unit":"Kg/kkg (or pounds per 1,000 lb) of product","statistic":"daily_max","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"direct","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is direct","cites is 40 CFR 415","the discharge is of the Subpart BA—Silver Nitrate Production Subcategory","existing sources (BPT)","table: Subpart BA—Silver Nitrate"],"cite":{"instrument":"us_40cfr415","title":"40 CFR Part 415 — PART 415—INORGANIC CHEMICALS MANUFACTURING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection 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0.164 0.068"}},{"id":"01807f84ca347258","parameter":"Silver","value":"0.068","value_num":0.068,"unit":"mg/troy ounce of silver reduced in solution","statistic":"monthly_avg","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"direct","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is direct","cites is 40 CFR 421","the discharge is of the Subpart W—Primary Precious Metals and Mercury Subcategory","existing sources (BPT)","(b) Silver chloride reduction spent solution.","table: BPT Limitations for the Primary Precious Metals and Mercury Subcategory"],"cite":{"instrument":"us_40cfr421","title":"40 CFR Part 421 — PART 421—NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 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CFR Part 421 — PART 421—NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 2026-10-05","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-05/title-40.xml?part=421","source_sha256":"d7cfd73b5bcf0e961e02ec53264492b2371277280003192841b7166b2a5012cf","fetched_at":"2026-10-09","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 421.252 (BPT)","page":null,"quote":"Silver 81.180 33.660"}},{"id":"942f2634ca3fd2c8","parameter":"Silver","value":"33.660","value_num":33.66,"unit":"mg/troy ounce of gold refined electrolytically","statistic":"monthly_avg","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"direct","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is direct","cites is 40 CFR 421","the discharge is of the Subpart W—Primary Precious Metals and Mercury Subcategory","existing sources (BPT)","(c) Electrolytic cells wet 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(BPT)","page":null,"quote":"Silver 0.021 0.009"}},{"id":"ceb0e3d42d609c42","parameter":"Silver","value":"76.340","value_num":76.34,"unit":"mg/kg (pounds per million pounds) of mercury condensed","statistic":"daily_max","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"direct","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is direct","cites is 40 CFR 421","the discharge is of the Subpart W—Primary Precious Metals and Mercury Subcategory","existing sources (BPT)","(e) Calciner wet air pollution control.","table: BPT Limitations for the Primary Precious Metals and Mercury Subcategory"],"cite":{"instrument":"us_40cfr421","title":"40 CFR Part 421 — PART 421—NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 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CFR Part 421 — PART 421—NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY","issuer":"U.S. Environmental Protection Agency","edition":"eCFR as of 2026-10-05","source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-10-05/title-40.xml?part=421","source_sha256":"d7cfd73b5bcf0e961e02ec53264492b2371277280003192841b7166b2a5012cf","fetched_at":"2026-10-09","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"40 CFR 421.252 (BPT)","page":null,"quote":"Silver 76.340 31.650"}},{"id":"204cb32b3b2d81b3","parameter":"Silver","value":"7.216","value_num":7.216,"unit":"mg/kg (pounds per million pounds) of mercury condensed","statistic":"daily_max","direction":"max","kind":"limit","medium":"water_discharge","level":"national","route":"direct","parameter_key":"cas:7440-22-4","place":["US"],"conditions":["route is direct","cites is 40 CFR 421","the discharge is of the Subpart W—Primary Precious Metals and Mercury Subcategory","existing sources (BPT)","(f) Calcine quench 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