{"query":{"parameter":"nickel total","place":"US-MN","medium":null,"statistic":null,"kind":null},"searched":{"places":["US-MN","US"],"parameter_keys":["cas:7440-02-0","name:nickel - total","name:nickel, total","name:iron, nickel (h), zinc","cas:373-02-4","cas:3333-67-3","cas:13463-39-3","name:nickel extractible","cas:12054-48-7","cas:1313-99-1","name:nickel refinery dust","cas:12035-72-2","name:total nickel"],"names_matched":[["nickel total","cas:7440-02-0"],["nickel total","name:nickel - total"],["nickel total","name:nickel, total"],["iron nickel h zinc","name:iron, nickel (h), zinc","nickel"],["iron nickel h zinc h","name:iron, nickel (h), zinc","nickel"],["nickel acetate","cas:373-02-4","nickel"],["nickel carbonate","cas:3333-67-3","nickel"],["nickel carbonyl","cas:13463-39-3","nickel"],["nickel carbonyl ni co 4 t 4","cas:13463-39-3","nickel"],["nickel extractible","name:nickel extractible","nickel"],["nickel hydroxide","cas:12054-48-7","nickel"],["nickel hydroxide ni oh 2","cas:12054-48-7","nickel"],["nickel ii acetate","cas:373-02-4","nickel"],["nickel ii oxide","cas:1313-99-1","nickel"],["nickel oxide","cas:1313-99-1","nickel"],["nickel refinery dust","name:nickel refinery dust","nickel"],["nickel subsulfide","cas:12035-72-2","nickel"],["total nickel","name:total nickel","nickel"],["total nickel freshwater","name:total nickel","nickel"],["total nickel marine","name:total nickel","nickel"]],"match":"exact+contains","order":"The place's own instruments first, then each place above it, each in its register's order; rows for a marine receiving water after the rest, as none of the place's own rows names a marine, salt, estuarine, coastal or ocean water"},"total":2177,"offset":0,"returned":50,"next_offset":50,"rows":[{"id":"1eee916b9557bbd0","parameter":"Nickel, total","value":"297","value_num":297,"unit":"µg/L","statistic":"monthly_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","the human health-based CS, where the rule sets it: The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total hardness values less than 212 mg/L, the CS in μg/L is toxicity-based and shall not exceed: exp.(0.846[ln(total hardness mg/L)]+1.1645)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":112,"quote":"The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total​"}},{"id":"64c2157db6f3ce8a","parameter":"Nickel, total","value":"The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total hardness values less than 212 mg/L, the CS in μg/L is toxicity-based and shall not exceed: exp.(0.846[ln(total hardness mg/L)]+1.1645)","unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":112,"quote":"The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total​"}},{"id":"4eda180392f43be9","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/L)]+3.3612)","unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":112,"quote":"The MS in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/L)]+3.3612)​"}},{"id":"d0d973547c2b31a5","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/L)]+4.0543)","unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":112,"quote":"The FAV in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/L)]+4.0543)​"}},{"id":"f5f78bf9c698af4a","parameter":"Nickel, total","value":"88","value_num":88,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"b3a4f87fadc5c51f","parameter":"Nickel, total","value":"158","value_num":158,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"b27610e35205f533","parameter":"Nickel, total","value":"283","value_num":283,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"66f2d743dc5a75aa","parameter":"Nickel, total","value":"297","value_num":297,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"118e8c6715452680","parameter":"Nickel, total","value":"297","value_num":297,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"9ac2ba3b256a4a4c","parameter":"Nickel, total","value":"789","value_num":789,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"2100843273e3b8f8","parameter":"Nickel, total","value":"1,418","value_num":1418,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"838914adb2dc6b63","parameter":"Nickel, total","value":"2,549","value_num":2549,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"516affe01cf8b170","parameter":"Nickel, total","value":"3,592","value_num":3592,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"28bfd8a9a063c708","parameter":"Nickel, total","value":"4,582","value_num":4582,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"7c63ad0b12f78952","parameter":"Nickel, total","value":"1,578","value_num":1578,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"7838d74b9ef2af40","parameter":"Nickel, total","value":"2,836","value_num":2836,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"2ad264504623f11b","parameter":"Nickel, total","value":"5,098","value_num":5098,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"c27ffbc452e20fe1","parameter":"Nickel, total","value":"7,185","value_num":7185,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"bac2f01b664d12f1","parameter":"Nickel, total","value":"9,164","value_num":9164,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2A waters: coldwater aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 2; each water's class is listed in 7050.0470)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 2","page":113,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"18d12b9a7e31bae8","parameter":"Nickel, total","value":"297","value_num":297,"unit":"µg/L","statistic":"monthly_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","the human health-based CS, where the rule sets it: The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total hardness values less than 212 mg/L, the CS in μg/L is toxicity-based and shall not exceed: exp.(0.846[ln(total hardness mg/L)]+1.1645)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total​"}},{"id":"07222b1938c38cd2","parameter":"Nickel, total","value":"The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total hardness values less than 212 mg/L, the CS in μg/L is toxicity-based and shall not exceed: exp.(0.846[ln(total hardness mg/L)]+1.1645)","unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"The CS shall not exceed the human health-based standard of 297 μg/L. For waters with total​"}},{"id":"6500fec7ef425df1","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/L)]+3.3612)","unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"The MS in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/L)]+3.3612)​"}},{"id":"a0a69e427a7458d5","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/L)]+4.0543)","unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"The FAV in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/L)]+4.0543)​"}},{"id":"e793413033bf7e83","parameter":"Nickel, total","value":"88","value_num":88,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"e80a47105ec68a11","parameter":"Nickel, total","value":"158","value_num":158,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"c7fe8a68c5f7e483","parameter":"Nickel, total","value":"283","value_num":283,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"006eeffb89902ad8","parameter":"Nickel, total","value":"297","value_num":297,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"197eb91cff02b114","parameter":"Nickel, total","value":"297","value_num":297,"unit":"µg/L","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":127,"quote":"CS μg/L​ 88​ 158​ 283​ 297​ 297​"}},{"id":"9304d9330fbf105d","parameter":"Nickel, total","value":"789","value_num":789,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"497a4f9fad97a2df","parameter":"Nickel, total","value":"1,418","value_num":1418,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"d9990a54d0859a05","parameter":"Nickel, total","value":"2,549","value_num":2549,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"41e75b73a7e7bddc","parameter":"Nickel, total","value":"3,592","value_num":3592,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"8928a002079b9937","parameter":"Nickel, total","value":"4,582","value_num":4582,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"5e436aeda92f7dbb","parameter":"Nickel, total","value":"1,578","value_num":1578,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"026817bc312219db","parameter":"Nickel, total","value":"2,836","value_num":2836,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"0c4e7c7b43317178","parameter":"Nickel, total","value":"5,098","value_num":5098,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2Bd waters: cool or warm water aquatic life and habitats, also protected as a source of drinking water (Minn. R. 7050.0222 subp. 3)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. 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R. 7050.0222 subp. 3)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. 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R. 7050.0222 subp. 3)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 3","page":128,"quote":"FAV μg/L​ 1,578​ 2,836​ 5,098​ 7,185​ 9,164​"}},{"id":"b04f07042ee09658","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/L)]+1.1645)","unit":"µg/L","statistic":"four_day_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"The CS in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/L)]+1.1645)​"}},{"id":"8dbd925a23969736","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/L)]+3.3612)","unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"The MS in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/L)]+3.3612)​"}},{"id":"1b51851e54bfbddc","parameter":"Nickel, total","value":"exp.(0.846[ln(total hardness mg/l)]+4.0543)","unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness-dependent: the printed equation; not evaluated"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"The FAV in μg/L shall not exceed: exp.(0.846[ln(total hardness mg/l)]+4.0543)​"}},{"id":"0c25d4b52de1a91c","parameter":"Nickel, total","value":"88","value_num":88,"unit":"µg/L","statistic":"four_day_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"CS μg/L​ 88​ 158​ 283​ 399​ 509​"}},{"id":"294fb7aa623cc942","parameter":"Nickel, total","value":"158","value_num":158,"unit":"µg/L","statistic":"four_day_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"CS μg/L​ 88​ 158​ 283​ 399​ 509​"}},{"id":"545cbaaad4b5fa11","parameter":"Nickel, total","value":"283","value_num":283,"unit":"µg/L","statistic":"four_day_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 200 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"CS μg/L​ 88​ 158​ 283​ 399​ 509​"}},{"id":"10d9da6717a393d3","parameter":"Nickel, total","value":"399","value_num":399,"unit":"µg/L","statistic":"four_day_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"CS μg/L​ 88​ 158​ 283​ 399​ 509​"}},{"id":"f3d21df89a93f5b5","parameter":"Nickel, total","value":"509","value_num":509,"unit":"µg/L","statistic":"four_day_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 400 mg/L or above (above 400 mg/L, 400 mg/L is used)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"CS μg/L​ 88​ 158​ 283​ 399​ 509​"}},{"id":"a49c15c1c97fb20c","parameter":"Nickel, total","value":"789","value_num":789,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 50 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"aea0c802836fab12","parameter":"Nickel, total","value":"1,418","value_num":1418,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 100 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. 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R. 7050.0222 subp. 4","page":146,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}},{"id":"f29ce21d8743f236","parameter":"Nickel, total","value":"3,592","value_num":3592,"unit":"µg/L","statistic":"daily_avg","direction":"max","kind":"guideline","medium":"surface_water","level":"regional","parameter_key":"name:nickel, total","place":["US-MN"],"conditions":["receiving_water is freshwater","class 2B waters: cool or warm water aquatic life and habitats, not protected as a source of drinking water (Minn. R. 7050.0222 subp. 4); class 2D wetlands take these standards save dissolved oxygen, pH, temperature and chloride (subp. 6)","total hardness 300 mg/L (the rule's example)"],"cite":{"instrument":"us_mn_wqs","title":"Minnesota Rules ch. 7050 class 2 (2A, 2Bd, 2B/2D), class 4 and class 5 water quality standards, and ch. 7052 Lake Superior basin standards for GLI pollutants","issuer":"State of Minnesota, Pollution Control Agency","edition":"ch. 7050 as US EPA posts it in effect for CWA purposes (effective July 23, 2025; posting cover July 29, 2025), and ch. 7052 (effective June 26, 2018; Revisor publication 2017)","source_url":"https://www.epa.gov/sites/default/files/2014-12/documents/mnwqs-chapter-7050.pdf","source_sha256":"1d4e781bf7b39a79bf6ea8ce64daaa05bb6c4bd5b04a98219d606ae88dbac150","fetched_at":"2026-10-14","source_status":{"checked":"2026-10-15","status":"unchanged"},"section":"Minn. R. 7050.0222 subp. 4","page":146,"quote":"MS μg/L​ 789​ 1,418​ 2,549​ 3,592​ 4,582​"}}],"next":[{"tool":"check_values","says":"Has your user measured this? check_values sets each of their results beside every row held here, with a verdict and the row's cite.","arguments":{"place":"US-MN"},"needs":{"rows":"Your user's measured results, as their table prints them: [{parameter: \"nickel total\", value, unit}, ...], any other parameters too."},"post":"/api/v1/check"},{"tool":"read_certificate","says":"Has your user a laboratory certificate? read_certificate reads every row it prints, each with its page, and checks them against these limits.","arguments":{"place":"US-MN"},"needs":{"content_base64":"The laboratory's certificate (PDF) or its XLSX, XLS or CSV export, as base64; or file_url, a public https address of it."},"post":"/api/v1/certificate"}]}