c/EPA National Primary Drinking Water Regulation Crosswalk United States Environmental Protection Agency Control of Per- and Polyfluoroalkyl Substances (PFAS) ------- Office of Water (4606M) EPA 815-B-24-015 October 2024 ------- Subpart A—General 1 40 CFR 141.2 Definitions 1 40 CFR 141.6 Effective dates 2 Subpart C—Monitoring and Analytical Requirements 2 40 CFR 141.24 Organic chemicals, sampling and analytical requirements 2 40 CFR 141.28 Certified laboratories 3 Subpart F—Maximum Contaminant Level Goals for Organic Contaminants 3 40 CFR 141.50 Maximum contaminant level goals for organic contaminants 3 Subpart G—National Primary Drinking Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels 4 40 CFR 141.60 Effective dates 4 40 CFR 141.61 Maximum contaminant levels for organic contaminants 5 Subpart O—Consumer Confidence Reports 10 40 CFR 141.151 Purpose and applicability of this subpart 10 40 CFR 141.153 Content of the reports 10 Appendices to Subpart O of Part 141 10 Subpart Q—Public Notification of Drinking Water Violations 15 Appendices to Subpart Q of Part 141 15 Appendix A to Subpart Q of Part 141—NPDWR Violations and Other Situations Requiring Public Notice1 16 Appendix B to Subpart Qof Part 141—Standard Health Effects Language for Public Notification 16 Appendix C to Subpart Q of Part 141—List of Acronyms Used in Public Notification Regulation 19 Subpart Z—Control of Per- and Polyfluoroalkyl Substances (PFAS) 19 40 CFR 141.900 General requirements 19 40 CFR 141.901 Analytical requirements 20 40 CFR 141.902 Monitoring requirements 22 40 CFR 141.903 Compliance requirements 29 40 CFR 141.904 Reporting and recordkeeping requirements 32 40 CFR 141.905 Violations 34 Part 142 - National Primary Drinking Water Regulations Implementation 36 Subpart B—Primary Enforcement Responsibility 36 40 CFR 142.16 Special primacy requirements 36 Subpart G—Identification of Best Technology, Treatment Techniques or Other Means Generally Available 37 ------- 40 CFR 142.62 Variances and exemptions from the maximum contaminant levels for organic and inorganic chemicals 37 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Part 141 National Primary Drinking Water Regulations Subpart A—General 40 CFR 141.2 Definitions. Hazard index (HI) is the sum of component hazard quotients (HQs), which are calculated by dividing the measured regulated PFAS component contaminant concentration in water (e.g., expressed as parts per trillion (ppt) or nanograms per liter (ng/l)) by the associated Health-Based Water Concentration (HBWC) expressed in the same units as the measured concentration (e.g., ppt or ng/l). For PFAS, a mixture Hazard Index greater than 1 (unitless) is an exceedance of the MCL. 40 CFR 141.2 Hazard quotient (HQ) means the ratio of the measured concentration in drinking water to the health-based water concentration (HBWC). 40 CFR 141.2 Health-based water concentration (HBWC) means level below which there are no known or anticipated adverse health effects over a lifetime of exposure, including sensitive populations and life stages, and allows for an adequate margin of safety. 40 CFR 141.2 HFPO-DA or GenX chemicals means Chemical Abstract Service registration number 122499-17-6, chemical formula C6F1103-, International Union of Pure and Applied Chemistry preferred name 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)propanoate, along with its conjugate acid and any salts, derivatives, isomers, or combinations thereof. 40 CFR 141.2 PFBS means Chemical Abstract Service registration number 45187-15-3, chemical formula C4F9S03-, perfluorobutane sulfonate, along with its conjugate acid and any salts, derivatives, isomers, or combinations thereof. 40 CFR 141.2 PFHxS means Chemical Abstract Service registration number 108427-53-8, chemical formula C6F13S03-, perfluorohexane sulfonate, along with its conjugate acid and any salts, derivatives, isomers, or combinations thereof. 40 CFR 141.2 PFNA means Chemical Abstract Service registration number 72007-68-2, chemical formula C9F1702-, perfluorononanoate, along with its conjugate acid and any salts, derivatives, isomers, or combinations thereof. 40 CFR 141.2 Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 1 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) PFOA means Chemical Abstract Service registration number 45285-51-6, chemical formula C8F1502-, perfluorooctanoate, along with its conjugate acid and any salts, derivatives, isomers, or combinations thereof. 40 CFR 141.2 PFOS means Chemical Abstract Service registration number 45298-90-6, chemical formula C8F17S03-, perfluorooctanesulfonate, along with its conjugate acid and any salts, derivatives, isomers, or combinations thereof. 40 CFR 141.2 40 CFR 141.6 Effective dates. Except as provided in paragraphs (b) through (1) of this section the regulations set forth in this part take effect on June 24, 1977. 40 CFR 141.6(a) The regulations pertaining to the per- and polyfluoroalkyl substances (PFAS) chemicals set forth in subpart Z of this part are effective June 25, 2024. See § 141.900 for the compliance dates for provisions under subpart Z. Compliance with reporting requirements under subpart Z, in accordance with subparts O (the consumer confidence rule) and Q (the public notification rule) of this part are required on April 26, 2027, except for notification requirements in § 141.203 related to violations of the MCLs. The compliance date for the PFAS MCLs in § 141.61, as specified in § 141.60, and for § 141.203 notifications of violations of the PFAS MCLs is April 26, 2029. 40 CFR 141.6(1) Subpart C—Monitoring and Analytical Requirements 40 CFR 141.24 Organic chemicals, sampling and analytical requirements. Analysis of the contaminants listed in § 141.61(c) for the purposes of determining compliance with the maximum contaminant level shall be conducted as follows, with the exceptions that this paragraph (h) does not apply to regulated PFAS (see § 141.902) and no monitoring is required for aldicarb, aldicarb sulfoxide or aldicarb sulfone: 40 CFR 141.24(h) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 2 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) 40 CFR 141.28 Certified laboratories. For the purpose of determining compliance with §§ 141.21 through 141.27, 141.40, 141.74, 141.89, 141.402, 141.901, and 141.902, samples may be considered only if they have been analyzed by a laboratory certified by EPA or the State except that measurements of alkalinity, disinfectant residual, orthophosphate, pH, silica, temperature, and turbidity may be performed by any person acceptable to the State. 40 CFR 141.28(a) Subpart F—Maximum Contaminant Level Goals for Organic Contaminants. 40 CFR 141.50 Maximum contaminant level goals for organic contaminants. PFOA. 40 CFR 141.50(a)(24) PFOS. 40 CFR 141.50(a)(25) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 3 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Contaminant MCLG in mg/l (unless otherwise noted) 40 CFR 141.50(b)(34-37) ***** * Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) 1 (unitless)1. HFPO-DA 0.00001. PFHxS 0.00001. PFNA 0.00001. 1. The PFAS Mixture Hazard Index (HI) is the sum of component hazard quotients (HQs), which are calculated by dividing the measured component PFAS concentration in water by the corresponding contaminant's health-based water concentration (HBWC) when expressed in the same units (shown in ng/l). The HBWC for PFHxS is 10 ng/l; the HBWC for HFPO-DA is 10 ng/l; the HBWC for PFNA is 10 ng/l; and the HBWC for PFBS is 2000 ng/l. A PFAS Mixture Hazard Index greater than 1 (unitless) indicates an exceedance of the health protective level and indicates potential human health risk from the PFAS mixture in drinking water. Hazard Index = ([HFPO-DAwater ng/l]/[10 ng/l]) + ([PFBSwaterng/l]/[2000 ng/l]) + ([PFNAwater ng/l]/[10 ng/l]]) + ([PFHxSwater ng/l]/[10 ng/l]) HBWC = health-based water concentration HQ = hazard quotient ng/l = nanograms per liter PFASwater = the concentration of a specific PFAS in water Subpart G—National Primary Drinking Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels 40 CFR 141.60 Effective dates. The effective date for § 141.61(c)(2)(i) through (vii) is April 26, 2029. 40 CFR 141.60(a)(4)3 a Note: Language was amended on June 11, 2024, pursuant to technical correction published at 89 FR 49101. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 4 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) 40 CFR 141.61 Maximum contaminant levels for organic contaminants. The following maximum contaminant levels for volatile organic contaminants apply to community and non-transient, non-community water systems. Table 1 to Paragraph (a)—Maximum Contaminant Levels for Volatile Organic Contaminants 40 CFR 141.61(a)b The Administrator, pursuant to section 1412 of the Act, hereby identifies as indicated in table 2 to paragraph (b) of this section granular activated carbon (GAC), packed tower aeration (PTA), or oxidation (OX) as the best technology, treatment technique, or other means available for achieving compliance with the maximum contaminant level for organic contaminants identified in paragraphs (a) and (c) of this section, except for per- and polyfluoroalkyl substances (PFAS). Table 2 to Paragraph (b)—BAT for Organic Contaminants in § 141.61 (a) and (c), Except for PFAS 40 CFR 141.61(b)c The following maximum contaminant levels (MCLs) in paragraphs (c)(1) and (2) of this section for synthetic organic contaminants apply to community water systems and non-transient, non- community water systems; paragraph (c)(2) of this section also contains health-based water concentrations (HBWCs) for selected per- and poly-fluoroalkyl substances (PFAS) used in calculating the Haard Index. 40 CFR 141.61(c)d b Note: The EPA added the word "volatile" to the first sentence and assigned a table name and number to the first table. c Note: The EPA only changed the end of the last quoted sentence and the table heading. d Note: The sentence introducing 40 CFR 141.61(c) was amended in a June 11, 2024, technical correction to introduce a second paragraph for PFAS. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 5 ------- Paragraph (c)(1)—MCLs for Synthetic Organic Contaminants, Except CAS No. Contaminant MCL (mg/l) (i) 15972-60-8 Alachlor 0.002 (ii) 116-06-3 Aldicarb 0.003 (iii) 1646-87-3 Aldicarb sulfoxide 0.004 (iv) 1646-87-4 Aldicarb sulfone 0.002 (v) 1912-24-9 Atrazine 0.003 (vi) 1563-66-2 Carbofuran 0.04 (vii) 57-74-9 Chlordane 0.002 (viii) 96-12-8 Dibromochloropropane 0.0002 (ix) 94-75-7 2,4-D 0.07 (x) 106-93-4 Ethylene dibromide 0.00005 (xi) 76-44-8 Heptachlor 0.0004 (xii) 1024-57-3 Heptachlor epoxide 0.0002 (xiii) 58-89-9 Lindane 0.0002 (xiv) 72-43-5 Methoxychlor 0.04 (xv) 1336-36-3 Polychlorinated biphenyls 0.0005 (xvi) 87-86-5 Pentachlorophenol 0.001 (xvii) 8001-35-2 Toxaphene 0.003 (xviii) 93-72-1 2,4,5-TP 0.05 (xix) 50-32-8 Benzo[a]pyrene 0.0002 (xx) 75-99-0 Dalapon 0.2 (xxi) 103-23-1 Di(2-ethylhexyl) adipate 0.4 (xxii) 117-81-7 Di(2-ethylhexyl) phthalate 0.006 (xxiii) 88-85-7 Dinoseb 0.007 (xxiv) 85-00-7 Diquat 0.02 (xxv) 145-73-3 Endothall 0.1 (xxvi) 72-20-8 Endrin 0.002 (xxvii) 1071-53-6 Glyphosate 0.7 (xxviii) 118-74-1 Hexacholorbenzene 0.001 (xxix) 77-47-4 Hexachlorocyclopentadiene 0.05 (xxx) 23135-22-0 Oxamyl (Vydate) 0.2 (xxxi) 1918-02-1 Picloram 0.5 Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 40 CFR 141.61(c)(1)6 6 ------- (xxxii) 122-34-9 Simazine 0.004 (xxxiii) 1746-01-6 2,3,7,8-TCDD (Dioxin) 3 x 10 "8 SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Paragraph (c)(2) MCLs and HBWCs for PFAS. CAS. No. Contaminant MCL (mg/l) (unless otherwise noted) HBWC (mg/l) for hazard index calculation (i) Not applicable Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) 1 (unitless)1 Not applicable (ii) 122499-17-6 HFPO-DA 0.00001 0.00001 (iii) 45187-15-3 PFBS No individual MCL 0.002 (iv) 108427-53-8 PFHxS 0.00001 0.00001 (v) 72007-68-2 PFNA 0.00001 0.00001 (vi) 45285-51-6 PFOA 0.0000040 Not applicable (vii) 45298-90-6 PFOS 0.0000040 Not applicable 40 CFR 141.61(c)(2)f 1. The PFAS Mixture Hazard Index (HI) is the sum of component hazard quotients (HQs), which are calculated by dividing the measured component PFAS concentration in water by the relevant health-based water concentration when expressed in the same units (shown in ng/l for simplification). The HBWC for PFHxS is 10 ng/l; the HBWC for HFPO-DA is 10 ng/l; the HBWC for PFNA is 10 ng/l; and the HBWC for PFBS is 2000 ng/l. Hazard Index = ([HFPO-DAwater ng/l]/[10 ng/l]) + ([PFBSwater ng/l]/[2000 ng/l]) + ([PFNAwater ng/l]/[10 ng/l]) + ([PFHxSwater ng/l]/[ 10 ng/l]) e Note: The MCLs listed in this portion of the CFR were not changed, but the designation was changed pursuant to 89 FR 49101 to subparagraph (c)(1). f Note: This new content was originally listed on April 26, 2024, as a new table, then redesignated subparagraph (c)(2) in the technical correction published on June 11, 2024. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 7 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) HBWC = health-based water concentration HQ= hazard quotient ng/l = nanograms per liter PFASwater = the concentration of a specific PFAS in water The Administrator, pursuant to section 1412 of the Act, hereby identifies in table 3 to this paragraph (d) the best technology, treatment technique, or other means available for achieving compliance with the maximum contaminant levels for all regulated PFAS identified in paragraph (c) of this section: Table 3 to Paragraph (d)—Best Available Technologies for PFAS Listed in Paragraph (c) of This Section 40 CFR 141.61(d)6 Contaminant BAT Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) Anion exchange, GAC, reverse osmosis, nanofiltration. HFPO-DA Anion exchange, GAC, reverse osmosis, nanofiltration. PFHxS Anion exchange, GAC, reverse osmosis, nanofiltration. PFNA Anion exchange, GAC, reverse osmosis, nanofiltration. PFOA Anion exchange, GAC, reverse osmosis, nanofiltration. PFOS Anion exchange, GAC, reverse osmosis, nanofiltration. g Note: The table number originally assigned to this new table on April 26, 2024, was amended on June 11, 2024 (see 89 FR 49101). Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 8 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) The Administrator, pursuant to section 1412 of the Act, hereby identifies in table 4 to this paragraph (e) the affordable technology, treatment technique, or other means available to systems serving 10,000 persons or fewer for achieving compliance with the maximum contaminant levels for all regulated PFAS identified in paragraph (c) of this section: Table 4 to Paragraph (e)—Small System Compliance Technologies (SSCTs) for PFAS 40 CFR 141.61(e) Small System Compliance Technology1 Affordable for Listed Small System Categories2 Granular Activated Carbon All size categories. Anion Exchange All size categories. Reverse Osmosis, Nanofiltration3 3,301-10,000. 1. Section 1412(b)(4)(E)(ii) of SDWA specifies that SSCTs must be affordable and technically feasible for small systems. 2. The Act (ibid.) specifies three categories of small systems: (i) those serving 25 or more, but fewer than 501, (ii) those serving more than 500, but fewer than 3,301, and (iii) those serving more than 3,300, but fewer than 10,001. 3. Technologies reject a large volume of water and may not be appropriate for areas where water quantity may be an issue. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 9 ------- DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Subpart O—Consumer Confidence Reports 40 CFR 141.151 Purpose and applicability of this subpart. For the purpose of this subpart, detected means: at or above the levels prescribed by § 141.23(a)(4) for inorganic contaminants, at or above the levels prescribed by § 141.24(f)(7) for the contaminants listed in § 141.61(a), at or above the levels prescribed by § 141.24(h)(18) for the contaminants listed in § 141.61(c) (except PFAS), at or above the levels prescribed by § 141.131(b)(2)(iv) for the contaminants or contaminant groups listed in § 141.64, at or above the levels prescribed by § 141.25(c) for radioactive contaminants, and at or above the levels prescribed in § 141.902(a)(5) for PFAS listed in § 141.61(c). 40 CFR 141.153 Content of the reports. Hazard Index or HI. The Hazard Index is an approach that determines the health concerns associated with mixtures of certain PFAS in finished drinking water. Low levels of multiple PFAS that individually would not likely result in adverse health effects may pose health concerns when combined in a mixture. The Hazard Index MCL represents the maximum level for mixtures of PFHxS, PFNA, HFPO-DA, and/or PFBS allowed in water delivered by a public water system. A Hazard Index greater than 1 requires a system to take action. Appendices to Subpart O of Part 141 Appendix A to Subpart O of Part 141—Regulated Contaminants Appendix A to Subpart O of Part 141h SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) 40 CFR 141.151(d) 40 CFR 141.153(c)(3)(v) Contaminant Traditional To MCL in MCLG Major sources Health effects language (units) MCL in convert CCR in drinking mg/L for CCR, units water multiply by h Note: Rows are added for PFAS contaminants in alphabetical order under Synthetic Organic Contaminants. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 10 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Synthetic organic contaminants including pesticides and herbicides: * * * * * * ***** Hazard Index PFAS (HFPODA, PFBS, PFHxS, and PFNA) (unitless) 1 (unitless) 1 1 Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities Per- and polyfluoroalkyl substances (PFAS) can persist in the human body and exposure may lead to increased risk of adverse health effects. Low levels of multiple PFAS that individually would not likely result in increased risk of adverse health effects may result in adverse health effects when combined in a mixture. Some people who consume drinking water containing mixtures of PFAS in excess of the Hazard Index (HI) MCL may have increased health risks such as liver, immune, and thyroid effects following exposure over many years and developmental and thyroid effects following repeated exposure during pregnancy and/or childhood. HFPO-DA (ng/l) 0.00001 1,000,000 10 10 Discharge from manufacturing and industrial Some people who drink water containing HFPODA in excess of the MCL over many years may Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 11 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities have increased health risks such as immune, liver, and kidney effects. There is also a potential concern for cancer associated with HFPO-DA exposure. In addition, there may be increased risks of developmental effects for people who drink water containing HFPODA in excess of the MCL following repeated exposure during pregnancy and/or childhood. ***** PFHxS (ng/l) 0.00001 1,000,000 10 10 Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities Some people who drink water containing PFHxS in excess of the MCL over many years may have increased health risks such as immune, thyroid, and liver effects. In addition, there may be increased risks of developmental effects for people who drink water containing PFHxS in excess of the MCL following repeated exposure during pregnancy and/or childhood. PFNA (ng/l) 0.00001 1,000,000 10 10 Discharge from manufacturing and industrial chemical facilities, use of certain Some people who drink water containing PFNA in excess of the MCL over many years may have increased health risks such as elevated cholesterol levels, immune effects, and liver effects. In addition, there Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 12 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) consumer products, occupational exposures, and certain firefighting activities may be increased risks of developmental effects for people who drink water containing PFNA in excess of the MCL following repeated exposure during pregnancy and/or childhood. PFOA (ng/l) 0.0000040 1,000,000 4.0 0 Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational exposures, and certain firefighting activities Some people who drink water containing PFOA in excess of the MCL over many years may have increased health risks such as cardiovascular, immune, and liver effects, as well as increased incidence of certain types of cancers including kidney and testicular cancer. In addition, there may be increased risks of developmental and immune effects for people who drink water containing PFOA in excess of the MCL following repeated exposure during pregnancy and/or childhood. PFOS (ng/l) 0.0000040 1,000,000 4.0 0 Discharge from manufacturing and industrial chemical facilities, use of certain consumer products, occupational Some people who drink water containing PFOS in excess of the MCL over many years may have increased health risks such as cardiovascular, immune, and liver effects, as well as increased incidence of certain types of cancers including liver cancer. In addition, there may be Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 13 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) exposures, and certain firefighting activities increased risks of developmental and immune effects for people who drink water containing PFOS in excess of the MCL following repeated exposure during pregnancy and/or childhood. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 14 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Subpart Q—Public Notification of Drinking Water Violations Appendices to Subpart Q of Part 1411 1 Note: Only rows added for PFAS contaminants are shown. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 15 ------- Appendix A to Subpart Q of Part 141—NPDWR Violations and Other Situations Requiring Public Notice1 Contaminant MCL/MRDL/TT violations2 Monitoring & testing procedure violations Tier of public notice required Citation Tier of public notice required Citation ***** D. Synthetic Organic Chemicals (SOCs) ***** 31. Hazard Index PFAS 223, * 141.61(c) 3 141.905(c) 32. HFPO-DA 2* 141.61(c) 3 141.905(c) 33. PFHxS 2* 141.61(c) 3 141.905(c) 34. PFNA 2* 141.61(c) 3 141.905(c) 35. PFOA 2* 141.61(c) 3 141.905(c) 36. PFOS 2* 141.61(c) 3 141.905(c) ***** Appendix A—Endnotes' *Beginning April 26, 2029. 1. Violations and other situations not listed in this table (e.g., failure to prepare Consumer Confidence Reports), do not require notice, unless otherwise determined by the primacy agency. Primacy agencies may, at their option, also require a more stringent public notice tier (e.g., Tier 1 instead of Tier 2 or Tier 2 instead of Tier 3) for specific violations and situations listed in this Appendix, as authorized under § 141.202(a) and § 141.203(a). 2. MCL—Maximum contaminant level, MRDL—Maximum residual disinfectant level, TT— Treatment technique. 23. Systems that violate the Hazard Index MCL and one or more individual MCLs based on the same contaminants may issue one notification to satisfy the public notification requirements for multiple violations pursuant to § 141.203. Appendix A to Subpart Q of Part 141 Appendix B to Subpart Q of Part 141—Standard Health Effects Language for Public Notification J Note: Endnotes 1 and 2 were not changed, but were reprinted in the Federal Register Notice. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 16 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Contaminant MCLG1 mg/L MCL2 mg/L Standard health effects language for public notification E. Synthetic Organic Chemicals (SOCs) ***** 55. Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) 1 (unitless) 1 (unitless) Per- and polyfluoroalkyl substances (PFAS) can persist in the human body and exposure may lead to increased risk of adverse health effects. Low levels of multiple PFAS that individually would not likely result in increased risk of adverse health effects may result in adverse health effects when combined in a mixture. Some people who consume drinking water containing mixtures of PFAS in excess of the Hazard Index (HI) MCL may have increased health risks such as liver, immune, and thyroid effects following exposure over many years and developmental and thyroid effects following repeated exposure during pregnancy and/or childhood. 56. HFPO-DA 0.00001 0.00001 Some people who drink water containing HFPO-DA in excess of the MCL over many years may have increased health risks such as immune, liver, and kidney effects. There is also a potential concern for cancer associated with HFPO-DA exposure. In addition, there may be increased risks of developmental effects for people who drink water containing HFPO-DA in excess of the MCL following repeated exposure during pregnancy and/or childhood. 57. PFHxS 0.00001 0.00001 Some people who drink water containing PFHxS in excess of the MCL over many years may have increased health risks such as immune, thyroid, and liver effects. In addition, there may be increased Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 17 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) risks of developmental effects for people who drink water containing PFHxS in excess of the MCL following repeated exposure during pregnancy and/or childhood. 58. PFNA 0.00001 0.00001 Some people who drink water containing PFNA in excess of the MCL over many years may have increased health risks such as elevated cholesterol levels, immune effects, and liver effects. In addition, there may be increased risks of developmental effects for people who drink water containing PFNA in excess of the MCL following repeated exposure during pregnancy and/or childhood. 59. PFOA Zero 0.0000040 Some people who drink water containing PFOA in excess of the MCL over many years may have increased health risks such as cardiovascular, immune, and liver effects, as well as increased incidence of certain types of cancers including kidney and testicular cancer. In addition, there may be increased risks of developmental and immune effects for people who drink water containing PFOA in excess of the MCL following repeated exposure during pregnancy and/or childhood. 60. PFOS Zero 0.0000040 Some people who drink water containing PFOS in excess of the MCL over many years may have increased health risks such as cardiovascular, immune, and liver effects, as well as increased incidence of certain types of cancers including liver cancer. In addition, there may be increased risks of developmental and immune effects for people who drink water containing PFOS in excess of the MCL following repeated exposure during pregnancy and/or childhood. ***** Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 18 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) 1. MCLG-Maximum contaminant level goal. 2. MCL-Maximum contaminant level. Appendix C to Subpart Q of Part 141—List of Acronyms Used in Public Notification Regulation HI Hazard Index PFAS Per-and Polyfluoroalkyl Substances Subpart Z—Control of Per- and Polyfluoroalkyl Substances (PFAS) 40 CFR 141.900 General requirements. The requirements of this subpart constitute the national primary drinking water regulations for PFAS. Each community water system (CWS) and non-transient, non-community water system (NTNCWS) must meet the requirements of this subpart including the maximum contaminant levels for the PFAS identified in § 141.61(c). 40 CFR 141.900(a) The deadlines for complying with the provisions of this subpart are as follows: 40 CFR 141.900(b) Each system must meet the analytical requirements in § 141.901 by June 25, 2024. 40 CFR 141.900(b)(1) Each system must report the results of initial monitoring, as described in § 141.902(b)(1), to the State by April 26, 2027. 40 CFR 141.900(b)(2) Each system must meet the compliance monitoring requirements in § 141.902(b)(2) by April 26, 2027. 40 CFR 141.900(b)(3) Each system must meet the MCL compliance requirements in § 141.903 by April 26, 2029. 40 CFR 141.900(b)(4) Each system must meet the reporting and recordkeeping requirements in § 141.904 by April 26, 2027. 40 CFR 141.900(b)(5) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 19 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Violations described in § 141.905 include monitoring and reporting violations and violations of MCLs. Monitoring and reporting violations may be assessed beginning on April 26, 2027. MCL violations may be assessed beginning on April 26, 2029. 40 CFR 141.900(b)(6) 40 CFR 141.901 Analytical requirements. General. 40 CFR 141.901(a) Systems must use only the analytical methods specified in this section to demonstrate compliance with the requirements of this subpart. 40 CFR 141.901(a)(1) The following documents are incorporated by reference with the approval of the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. This material is available for inspection at the EPA and at the National Archives and Records Administration (NARA). Contact the EPA's Drinking Water Docket at 1301 Constitution Avenue, NW., EPA West, Room 3334, Washington, DC 20460; phone: 202-566-2426. For information on the availability of this material at NARA, email: fr.inspection@nara.gov, or go to: www.archives.gov/federal- register/cfr/ibr-locations. The material may be obtained from the EPA at 1301 Constitution Avenue, NW., the EPA West, Room 3334, Washington, DC 20460; phone 202-566-2426; or go to: https://www.epa.gov/pfas/epa-pfas-drinking-water-laboratorymethods. 40 CFR 141.901(a)(2) EPA Method 533: Determination of Per- and Polyfluoroalkyl Substances in Drinking Water by Isotope Dilution Anion Exchange Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry, 815-B-19-020, November 2019. 40 CFR 141.901(a)(2)(i) Method 537.1, Version 2.0: Determination of Selected Per- and Polyfluorinated Alkyl Substances in Drinking Water by Solid Phase Extraction and Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS), EPA/600/R-20/006, March 2020. 40 CFR 141.901(a)(2)(ii) PFAS— 40 CFR 141.901(b) Analytical methods. Systems must measure regulated PFAS by the methods listed in the following table: 40 CFR 141.901(b)(1) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 20 ------- DIFFERENT STATE CITATION FROM FEDERAL SUMMARY OF FEDERAL REQUIREMENT FEDERAL (DOCUMENT TITLE, REQUIREMENT? CITATION PAGE NUMBER (EXPLAIN ON SECTION/PARAGRAPH) SEPARATE SHEET) Table 1 to Paragraph (b)(1)—Analytical Methods for PFAS Contaminants 40 CFR Contaminant Methodology EPA Method (incorporated by reference, see paragraph (a) of this section) 141.901(b)(1) Perfluorobutane Sulfonate (PFBS) SPE LC-MS/MS 533, 537.1 version 2.0 Perfluorohexane Sulfonate (PFHxS) SPE LC-MS/MS 533, 537.1 version 2.0 Perfluorononanoate (PFNA) SPE LC-MS/MS 533, 537.1 version 2.0 Perfluorooctanesulfonic Acid (PFOS) SPE LC-MS/MS 533, 537.1 version 2.0 Perfluorooctanoic Acid (PFOA) SPE LC-MS/MS 533, 537.1 version 2.0 2,3,3,3-Tetrafluoro-2- SPE LC-MS/MS 533, 537.1 version 2.0 (heptafluoropropoxy)propanoate (HFPO-DA or GenX Chemicals) Laboratory certification. Analyses under this section for regulated PFAS must only be conducted 40 CFR by laboratories that have been certified by EPA or the State. To receive certification to conduct 141.901(b)(2) analyses for the regulated PFAS, the laboratory must: Analyze Performance Evaluation (PE) samples that are acceptable to the State at least once 40 CFR during each consecutive 12-month period by each method for which the laboratory desires 141.901(b)(2)(i) certification. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 21 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Beginning June 25, 2024, achieve quantitative results on the PE sample analyses that are within the following acceptance limits: 40 CFR 141.901(b)(2)(ii) Table 2 to Paragraph (b)(2)(ii)—Acceptance Limits for PFAS Performance Evaluation Samples Contaminant Acceptance Limits (percent of true value) Perfluorobutane Sulfonate (PFBS) 70-130 Perfluorohexane Sulfonate (PFHxS) 70-130 Perfluorononanoate (PFNA) 70-130 Perfluorooctanesulfonic Acid (PFOS) 70-130 Perfluorooctanoic Acid (PFOA) 70-130 2,3,3,3-Tetrafluoro-2- (heptafluoropropoxy)propanoate (HFPO-DA or GenX Chemicals) 70-130 For all samples analyzed for regulated PFAS in compliance with § 141.902, beginning June 25, 2024, report data for concentrations as low as the trigger levels as defined in § 141.902(a)(5). 40 CFR 141.901(b)(2)(iii) 40 CFR 141.902 Monitoring requirements. General requirements. 40 CFR 141.902(a) Systems must take all samples during normal operating conditions at all entry points to the distribution system. 40 CFR 141.902(a)(1) If the system draws water from more than one source and the sources are combined before distribution, the system must sample at an entry point to the distribution system during periods of representative operating conditions. 40 CFR 141.902(a)(2) Systems must use only data collected under the provisions of this subpart to qualify for reduced monitoring. 40 CFR 141.902(a)(3) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 22 ------- DIFFERENT STATE CITATION FROM FEDERAL SUMMARY OF FEDERAL REQUIREMENT FEDERAL (DOCUMENT TITLE, REQUIREMENT? CITATION PAGE NUMBER (EXPLAIN ON SECTION/PARAGRAPH) SEPARATE SHEET) All new systems that begin operation after, or systems that use a new source of water after April 40 CFR 26, 2027, must demonstrate compliance with the MCLs within a period of time specified by the 141.902(a)(4) State. A system must also comply with initial sampling frequencies required by the State to ensure that the system can demonstrate compliance with the MCLs. Compliance monitoring frequencies must be conducted in accordance with the requirements in this section. For purposes of this section, the trigger levels are defined as shown in the following table. 40 CFR 141.902(a)(5) Table 1 to Paragraph (a)(5)—Trigger Levels for PFAS Contaminants Contaminant Trigger level Hazard Index PFAS (HFPO-DA, 0.5 (unitless). PFBS, PFHxS, PFNA) HFPO-DA 5 nanograms per liter (ng/l). PFHxS 5 ng/l. PFNA 5 ng/l. PFOA 2.0 ng/l. PFOS 2.0 ng/l. Based on initial monitoring results, for each sampling point at which a regulated PFAS listed in 40 CFR § 141.61(c) is detected at a level greater than or equal to the trigger level, the system must 141.902(a)(6) monitor quarterly for all regulated PFAS beginning April 26, 2027, in accordance with paragraph (b)(2) of this section. For purposes of this section, each water system must ensure that all results provided by a 40 CFR laboratory are reported to the State and used for determining the required sampling 141.902(a)(7) frequencies. This includes values below the practical quantitation levels defined in § 141.903(f)(l)(iv); zero must not be used in place of reported values. Monitoring requirements for PFAS. 40 CFR 141.902(b) Initial monitoring. 40 CFR 141.902(b)(1) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 23 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Groundwater CWS and NTNCWS serving greater than 10,000 persons and all surface water CWS and NTNCWS must take four consecutive samples 2 to 4 months apart within a 12-month period (quarterly samples) for each regulated PFAS listed in § 141.61(c). 40 CFR 141.902(b)(l)(i) All groundwater CWS and NTNCWS serving 10,000 or fewer persons must take two samples for each regulated PFAS listed in § 141.61(c) five to seven months apart within a 12-month period. 40 CFR 141.902(b)(l)(ii) All groundwater under the direct influence of surface water (GWUDI) CWS and NTNCWS must follow the surface water CWS and NTNCWS monitoring schedule in paragraph (b)(l)(i) of this section. 40 CFR 141.902(b)(l)(iii) All systems that use both surface water and groundwater must apply the requirements in paragraphs (b)(l)(i) through (iii) of this section depending on the source(s) of water provided at a given entry point to the distribution system (EPTDS). If the EPTDS provides surface water, the requirements for a surface water CWS/NTNCWS apply. If the EPTDS provides groundwater, the requirements for a groundwater CWS/NTNCWS apply, based on system size. If an EPTDS provides a blend of surface water and groundwater, the requirements for a surface water system apply. For systems that change the source water type at an EPTDS during the initial monitoring period (i.e., one part of the year it is surface water and the remaining part of the year it is groundwater), the sampling requirements for a surface water system apply. 40 CFR 141.902(b)(l)(iv) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 24 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Systems must monitor at a frequency indicated in the following table, though a State may require more frequent monitoring on a system-specific basis: Table 2 to Paragraph (b)(l)(v)—Initial Monitoring Requirements 40 CFR 141.902(b)(l)(v) Type of System Minimum Monitoring Frequency Sample Location Groundwater CWS and NTNCWS serving greater than 10,000 persons, all surface water CWS and NTNCWS, and all GWUDI systems Four consecutive quarters of samples per entry point to the distribution system (EPTDS) within a 12-month period, unless the exception in paragraph (b)(l)(viii) of this section applies. Samples must be taken two to four months apart. Sampling point for EPTDS. Groundwater CWS and NTNCWS serving 10,000 or fewer persons Two consecutive samples per EPTDS within a 12-month period, unless the exception in paragraph (b)(l)(viii) of this section applies. Samples must be taken five to seven months apart. Sampling point for EPTDS. A State may accept data that has been previously acquired by a water system to count toward the initial monitoring requirements if the data meet the requirements of § 141.901(b)(1), samples were collected starting on or after January 1, 2019, and otherwise meet the timing requirements specified in table 2 to paragraph (b)(l)(v) of this section. For the purposes of satisfying initial monitoring requirements, acceptable data may be reported to a concentration no greater than the MCLs. However, a system is only eligible for triennial monitoring at the start of the compliance monitoring period if the system demonstrates that concentrations in all samples it uses to satisfy the initial monitoring requirements are below the trigger levels as defined in paragraph (a)(5) of this section. 40 CFR 141.902(b)(l)(vi) If systems have multiple years of data, the most recent data must be used. 40 CFR 141.902(b)(l)(vii) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 25 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) For systems using previously acquired data that have fewer than the number of samples required in a continuous 12-month period for initial monitoring as listed in table 2 to paragraph (b)(l)(v) of this section: All surface water systems, GWUDI systems, and groundwater systems serving greater than 10,000 persons must collect in a calendar year one sample in each quarter that was not represented, two to four months apart from the months with available data; All groundwater systems serving 10,000 or fewer persons must collect one sample in the month that is five to seven months apart from the month in which the previous sample was taken. 40 CFR 141.902(b)(l)(viii) In determining the most recent data to report, a system must include all results provided by a laboratory whether above or below the practical quantitation levels. These results must be used for the purposes of determining the frequency with which a system must monitor at that sampling point at the start of the compliance monitoring period. 40 CFR 141.902(b)(l)(ix) States may delete results of obvious sampling errors. If the State deletes a result because of an obvious sampling error and the system fails to collect another sample this is a monitoring violation as described in § 141.905(c). 40 CFR 141.902(b)(l)(x) Initial monitoring requirements, including reporting results to the State, must be completed by April 26, 2027. 40 CFR 141.902(b)(l)(xi) Compliance monitoring. 40 CFR 141.902(b)(2) Based on initial monitoring results, at the start of the monitoring period that begins on April 26, 2027, systems may reduce monitoring at each sampling point at which all reported sample concentrations were below all trigger levels defined in paragraph (a)(5) of this section, unless otherwise provided for by the State. At eligible sampling points, each water system must analyze one sample for all regulated PFAS during each three-year monitoring period, at a time specified by the State, in the quarter in which the highest analytical result was detected during the most recent round of quarterly or semi-annual monitoring. If a sampling point is not eligible for triennial monitoring, then the water system must monitor quarterly at the start of the compliance monitoring period. 40 CFR 141.902(b)(2)(i) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 26 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) If, during the compliance monitoring period, a system is monitoring triennially and a PFAS listed in § 141.61(c) is detected at a level equal to or exceeding the trigger levels defined in paragraph (a)(5) of this section in any sample, then the system must monitor quarterly for all regulated PFAS beginning in the next quarter at the sampling point. The triggering sample must be used as the first quarter of monitoring for the running annual average calculation. 40 CFR 141.902(b)(2)(i For all source water types, a State may determine that all regulated PFAS at a sampling point are reliably and consistently below the MCL after considering, at a minimum, four consecutive quarterly samples collected during the compliance monitoring period. A sampling point that a State has determined to be reliably and consistently below the MCL is required to collect annual samples for at least the first three years after that determination is made. Annual samples must be collected in the quarter in which detected concentrations were highest during the most recent year of quarterly monitoring. If, after three consecutive years, annual samples all contain results that are below the trigger levels defined in paragraph (a)(5) of this section, the State may allow a system to begin triennial monitoring at the sampling point. The water system must collect triennial samples in the quarter with the highest concentrations during the most recent round of quarterly sampling. If an annual sample meets or exceeds an MCL or the State determines that the result is not reliably and consistently below the MCL for all regulated PFAS, then the system must monitor quarterly for all regulated PFAS beginning in the next quarter at the sampling point. 40 CFR 141.902(b)(2)(i The three different compliance monitoring sampling schedules that may be assigned and the criteria for each are summarized in the following table: Table 3 to Paragraph (b)(2)(iv)—Compliance Monitoring Schedules and Requirements 40 CFR 141.902(b)(2)(iv) Sampling frequency Eligibility requirements1 Sample timing requirements Triennial At an individual sampling point, either: (1) All initial monitoring results demonstrate concentrations of all regulated PFAS below trigger levels; (2) The most recent three consecutive annual monitoring results all Sample must be collected at a time within the three-year period designated by the State, in the quarter that yielded the highest analytical Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 27 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) demonstrated concentrations of all regulated PFAS below trigger levels; or (3) The previous triennial sample demonstrated all regulated PFAS concentrations below trigger levels. Note: After beginning compliance monitoring, a system may not transition directly from quarterly monitoring to triennial monitoring. result during the most recent round of quarterly sampling (or the most recent semi- annual sampling, if no quarterly sampling has occurred). Annual A State makes a determination that all regulated PFAS concentrations at the sampling point are reliably and consistently below PFAS MCLs, after considering, at a minimum, 4 consecutive quarterly samples collected during the compliance monitoring period. Sample must be collected at a time designated by the State, within the quarter that yielded the highest analytical result during the most recent round of quarterly sampling. Quarterly At an individual sampling point, either: (1) Any regulated PFAS concentration meets or exceeds a trigger level during initial monitoring; (2) Sampling is occurring quarterly during compliance monitoring and a State has not made a determination that all levels of regulated PFAS at the sampling point are reliably and consistently below the regulated PFAS MCLs; or (3) A sample collected by a system required to conduct triennial monitoring contains regulated PFAS concentrations that meet or exceed trigger levels. The first of these samples meeting or exceeding the trigger level is considered the first quarterly sample. (4) A sample collected by a system required to conduct annual monitoring contains regulated PFAS concentrations that meet or exceed an MCL. The first of these samples Samples must be collected in four consecutive quarters, on dates designated by the State. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 28 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) meeting or exceeding the MCL is considered the first quarterly sample. 1. The monitoring frequency at a sampling point must be the same for all regulated PFAS and is determined based on the most frequent sampling required for any regulated PFAS detected at a level at or exceeding the trigger level. The State may require a confirmation sample for any sampling result. If a confirmation sample is required by the State, the system must average the result with the first sampling result and the average must be used for the determination of compliance with MCLs as specified by § 141.903. A State may delete results of obvious sampling errors from the MCL compliance calculations described in § 141.903. If the State deletes a result because of an obvious sampling error and the system fails to collect another sample this is a monitoring violation as described in § 141.905(c). 40 CFR 141.902(b)(2)(v) The State may increase the required monitoring frequency, where necessary, to detect variations within the system (e.g., fluctuations in concentration due to seasonal use, changes in water source). 40 CFR 141.902(b)(2)(vi) Each public water system must monitor at the time designated by the State within each monitoring period. 40 CFR 141.902(b)(2)(vii) When a system reduces its sampling frequency to annual or triennial sampling, the next compliance sample must be collected in the monitoring period that begins the calendar year following State approval of a reduction in monitoring frequency. 40 CFR 141.902(b)(2)(viii) 40 CFR 141.903 Compliance requirements. Compliance with MCLs for regulated PFAS in § 141.61(c) must be determined based on the analytical results obtained at each sampling point. 40 CFR 141.903(a) For systems monitoring quarterly, compliance with the MCL is determined by the running annual average at each sampling point. 40 CFR 141.903(b) If a system fails to collect the required number of samples specified in § 141.902, this is a monitoring violation as described in § 141.905(c), and compliance calculations must be based on the total number of samples collected. 40 CFR 141.903(c) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 29 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Systems monitoring triennially whose sample result equals or exceeds the trigger level of 2.0 ng/l for either PFOS or PFOA, 5 ng/l for HFPO-DA, PFHxS, or PFNA, or a Hazard Index of 0.5 for the Hazard Index PFAS, must begin quarterly sampling for all regulated PFAS in the next quarter at the sampling point. Systems monitoring annually whose sample result equals or exceeds the MCL of 4.0 ng/l for either PFOS or PFOA, 10 ng/l for HFPO-DA, PFHxS, or PFNA, or a Hazard Index of 1 for the Hazard Index PFAS, must begin quarterly sampling for all regulated PFAS in the next quarter at the sampling point. 40 CFR 141.903(d) Except as provided in this paragraph (e), if a sample result exceeds an MCL, the system will not be considered in violation of the MCL until it has completed one year of quarterly sampling at the sampling point with the triggering sample used as the first quarter of monitoring for the running annual average calculation. However, whenever a sample result in any quarter (or quarterly average, if more than one compliance sample is available in a quarter because a confirmation sample was required by the State) causes the running annual average to exceed the MCL at a sampling point regardless of the subsequent quarterly monitoring results required to complete a full year of monitoring (e.g., the results from a single sample are more than 4 times the MCL), the system is out of compliance with the MCL immediately. 40 CFR 141.903(e) Systems must calculate compliance using the following method to determine MCL compliance at each sampling point: 40 CFR 141.903(f) For each PFAS regulated by an individual MCL: 40 CFR 141.903(f)(1) For systems monitoring quarterly, divide the sum of the measured quarterly concentrations for each analyte by the number of quarters samples were collected for that analyte during the consecutive quarters included in the calculation. If more than one compliance sample for that analyte is available in a quarter because a confirmation sample was required by the State, systems must average all the results in a quarter then average the quarterly averages. Rounding does not occur until the end of the calculation. If the running annual average exceeds the MCL, the system is not in compliance with the MCL requirements. 40 CFR 141.903(f)(l)(i) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 30 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) For systems monitoring annually, if the concentration measured is equal to or exceeds an MCL for regulated PFAS, the system is required to initiate quarterly monitoring for all regulated PFAS beginning in the next quarter at the sampling point, with the triggering sample result used as the first quarter of monitoring for the running annual average calculation. 40 CFR 141.903 (f)( l)(ii) For systems monitoring triennially, if the concentration measured is equal to or exceeds the trigger level, the system is required to initiate quarterly monitoring for all regulated PFAS beginning in the next quarter at the sampling point, with the triggering sample result used as the first quarter of monitoring for the running annual average calculation. 40 CFR 141.903 (f)( l)(iii) For the purpose of calculating MCL compliance, if a sample result is less than the practical quantitation level (PQL) for a regulated PFAS, in accordance with the following table, zero is used for that analyte solely to calculate the running annual average. 40 CFR 141.903 (f)( l)(iv) Table 1 to Paragraph (f)(l)(iv)—Practical Quantitation Levels (PQLs) for PFAS Contaminants Contaminant PQL (in parts per trillion) HFPO-DA 5.0 PFBS 3.0 PFHxS 3.0 PFNA 4.0 PFOA 4.0 PFOS 4.0 For each PFAS regulated under the Hazard Index MCL: 40 CFR 141.903(f)(2) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 31 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) For systems monitoring quarterly, divide the observed sample analytical result for each analyte included in the Hazard Index by the corresponding HBWC listed in § 141.61(c) to obtain a hazard quotient for each analyte for each sampling event at each sampling point. Sum the resulting hazard quotients together to determine the Hazard Index for the quarter. If the State requires a confirmation sample for an analyte in the quarter, systems must average these results for each analyte in that quarter and then determine the hazard quotient(s) from those average values, then sum the hazard quotients. Once the Hazard Indices for the individual quarters are calculated, they are averaged to determine a running annual average. If the running annual average Hazard Index exceeds the MCL and two or more Hazard Index analytes had an observed sample analytical result at or above the PQL in any of the quarterly samples collected to determine the running annual average, the system is in violation of the Hazard Index MCL. No rounding occurs until after the running annual average Hazard Index is calculated. 40 CFR 141.903 (f)(2)(i) If the Hazard Index calculated using the results of an annual sample equals or exceeds the Hazard Index MCL, the system must initiate quarterly sampling for all regulated PFAS beginning in the next quarter at the sampling point, with the triggering sample result used as the first quarter of monitoring. 40 CFR 141.903 (f)(2)(ii) If the Hazard Index calculated using the results of a triennial sample equals or exceeds the Hazard Index trigger level, the system must initiate quarterly sampling for all regulated PFAS beginning in the next quarter at the sampling point, with the triggering sample result used as the first quarter of monitoring. 40 CFR 141.903 (f)(2)(iii) If a sample result is less than the practical quantitation level for a regulated PFAS, in accordance with the table 1 to paragraph (f)(l)(iv) of this section, zero is used for that analyte solely to calculate the running annual average. 40 CFR 141.903 (f)(2)(iv) 40 CFR 141.904 Reporting and recordkeeping requirements. Systems required to sample must report to the State according to the timeframes and provisions of § 141.31 and retain records according to the provisions in § 141.33. 40 CFR 141.904 Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 32 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Systems must report the information from initial monitoring specified in the following table: Table 1 to Paragraph (a)—Data To Report From Initial Monitoring 40 CFR 141.904(a) If you are a ... You must report... System monitoring for regulated PFAS under the requirements of § 141.902(b)(1) on a quarterly basis 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations reported. 2. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples. System monitoring for regulated PFAS under the requirements of § 141.902(b)(1) less frequently than quarterly 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations reported. 2. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 33 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Systems must report the information collected during the compliance monitoring period specified in the following table: 40 CFR 141.904(b) Table 2 to Paragraph (b)—Data To Report From Compliance Monitoring If you are a ... You must report... System monitoring for regulated PFAS under the requirements of § 141.902(b)(2) on a quarterly basis 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations during the previous quarter. 2. The running annual average at each sampling point of all compliance samples. 3. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples. 4. Whether an MCL for a regulated PFAS in § 141.61(c) was met or exceeded in any samples. 5. Whether, based on § 141.903, an MCL was violated. System monitoring for regulated PFAS under the requirements of § 141.902(b)(2) less frequently than quarterly 1. All sample results, including the locations, number of samples taken at each location, dates, and concentrations during the previous monitoring period. 2. Whether a trigger level, defined in § 141.902(a)(5), was met or exceeded in any samples. 3. Whether an MCL for a regulated PFAS in § 141.61(c) was met or exceeded in any samples. 4. Whether, based on § 141.903, an MCL was violated (e.g., the results from a single sample are more than 4 times the MCL). 40 CFR 141.905 Violations. PFAS MCL violations, both for the individual PFOA, PFOS, HFPO-DA, PFHxS, and PFNA MCLs, as well as the Hazard Index MCL, as listed in § 141.61(c), are based on a running annual average, as outlined under § 141.903. 40 CFR 141.905(a) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 34 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION STATE CITATION (DOCUMENT TITLE, PAGE NUMBER SECTION/PARAGRAPH) DIFFERENT FROM FEDERAL REQUIREMENT? (EXPLAIN ON SEPARATE SHEET) Compliance with § 141.61(c) must be determined based on the analytical results obtained at each sampling point. If one sampling point is in violation of an MCL, the system is in violation of the MCL. 40 CFR 141.905(b) Each failure to monitor in accordance with the requirements under § 141.902 is a monitoring violation. 40 CFR 141.905(c) Failure to notify the State following a MCL violation and failure to submit monitoring data in accordance with the requirements of §§ 141.904 and 141.31 are reporting violations. 40 CFR 141.905(d) Results for PFAS with individual MCLs as listed in § 141.61(c) are compared to their respective MCLs, and results for mixtures of two or more of the Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) are compared to the Hazard Index MCL as listed in § 141.61(c). For determining compliance with the Hazard Index MCL, if only PFBS is reported at any concentration and no other regulated PFAS are in the mixture, it is not violation of the Hazard Index MCL. If only one of the other PFAS within the Hazard Index (HFPO-DA, PFHxS, and PFNA) is detected and the level of this PFAS exceeds its MCL as determined by § 141.903(f)(l)(i), only an individual MCL violation is assessed for the individual PFAS detected, and it is not a violation of the Hazard Index MCL. Exceedances of the Hazard Index caused by two or more of the Hazard Index PFAS (HFPO-DA, PFBS, PFHxS, and PFNA) and exceedances of one or more individual MCLs can result in multiple MCL exceedances. However, in this instance, for purposes of public notification under appendix A to subpart Q of this part, a PWS must only report the Hazard Index MCL exceedance. 40 CFR 141.905(e) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 35 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION EXPLANATION OF STATE POLICIES AND PROCEDURES Part 142- National Primary Drinking Water Regulations Implementation Subpart B—Primary Enforcement Responsibility 40 CFR 142.16 Special primacy requirements. Requirements for States to adopt 40 CFR part 141, subpart Z, PFAS. In addition to the general primacy requirements elsewhere in this part, including the requirements that State regulations be at least as stringent as Federal requirements, an application for approval of a State program revision that adopts 40 CFR part 141, subpart Z, must contain the following, in lieu of meeting the requirements of paragraph (e) of this section: 40 CFR 142.16(r) The State's procedures for reviewing the water system's use of pre-existing data to meet the initial monitoring requirements specified in § 141.902, including the criteria that will be used to determine if the data are acceptable. This paragraph (r)(l) is no longer applicable after the initial monitoring period ends on April 26, 2027. 40 CFR 142.16(r)(l) The State's procedures for ensuring all systems complete the initial monitoring period requirements that will result in a high degree of monitoring compliance by the regulatory deadlines. This paragraph (r)(2) is no longer applicable after the initial monitoring period ends on April 26, 2027. 40 CFR 142.16(r)(2) After the initial monitoring period, States establish the initial monitoring requirements for new public water systems and existing public water systems that plan to use a new source. States must explain their initial monitoring schedules and how these monitoring schedules ensure that new public water systems and existing public water systems that plan to use new sources comply with MCLs and monitoring requirements. States must also specify the time frame in which a new system or existing system that plans to use a new source must demonstrate compliance with the MCLs. 40 CFR 142.16(r)(3) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 36 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION EXPLANATION OF STATE POLICIES AND PROCEDURES Subpart G—Identification of Best Technology, Treatment Techniques or Other Means Generally Available 40 CFR 142.62 Variances and exemptions from the maximum contaminant levels for organic and inorganic chemicals. The Administrator, pursuant to section 1415(a)(1)(A) of the Act, hereby identifies the technologies listed in tables 1 and 2 to this paragraph (a) as the best available technology, treatment techniques, or other means available for achieving compliance with the maximum contaminant levels for the organic chemicals, including per- and polyfluoroalkyl substances (PFAS), listed in § 141.61 (a) and (c) of this chapter, for the purposes of issuing variances and exemptions. A list of small system compliance technologies for the regulated PFAS for the purposes of providing variances and exemptions is provided in table 3 to this paragraph (a); for the purpose of this paragraph (a), small system is defined as a system serving 10,000 persons or fewer. 40 CFR 142.62(a) Table 1 to Paragraph (a)—BATs for PFAS Listed in § 141.61(c) Contaminant BAT Hazard Index PFAS (HFPO- DA, PFBS, PFHxS, and PFNA) Anion exchange, GAC, reverse osmosis, nanofiltration. HFPO-DA Anion exchange, GAC, reverse osmosis, nanofiltration. PFHxS Anion exchange, GAC, reverse osmosis, nanofiltration. PFNA Anion exchange, GAC, reverse osmosis, nanofiltration. PFOA Anion exchange, GAC, reverse osmosis, nanofiltration. PFOS Anion exchange, GAC, reverse osmosis, nanofiltration. Table 2 to paragraph (a)—BATs for Other Synthetic Organic Contaminants Listed in § 141.61(c) and Volatile Organic Chemicals Listed in § 141.61(a) 40 CFR 142.62(a)(1)- Contaminant Best available technologies (54)k PTA1 GAC2 ox3 (1)Benzene X X (2) Carbon tetrachloride X X k Note: The EPA only added a table number and title to this table. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 37 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL EXPLANATION OF STATE POLICIES AND CITATION PROCEDURES (3) 1,2-Dichloroethane X X (4) Trichloroethylene X X (5) para-Dichlorobenzene X X (6) 1,1-Dichloroethylene X X (7) 1,1,1-Trichloroethane X X (8) Vinyl chloride X (9) cis-l,2-Dichloroethylene X X (10) 1,2-Dichloropropane X X (11) Ethylbenzene X X (12) Monochlorobenzene X X (13)o-Dichlorobenzene X X (14) Styrene X X (15) Tetrachloroethylene X X (16) Toluene X X (17) trans-l,2-Dichloroethylene X X (18) Xylense (total) X X (19) Alachlor X (20) Aldicarb X (21) Aldicarb sulfoxide X (22) Aldicarb sulfone X (23) Atrazine X (24) Carbofuran X (25) Chlordane X (26) Dibromochloropropane X X (27) 2,4-D X (28) Ethylene dibromide X X (29) Heptachlor X (30) Heptachlor epoxide X (31) Lindane X (32) Methoxychlor X (33) PCBs X Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 38 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL EXPLANATION OF STATE POLICIES AND CITATION PROCEDURES (34) Pentachlorophenol X (35)Toxaphene X (36) 2,4,5-TP X (37) Benzo[a]pyrene X (38) Dalapon X (39) Dichloromethane X (40) Di(2-ethylhexyl)adipate X X (41) Di(2-ethylhexyl)phthalate X (42) Dinoseb X (43) Diquat X (44) Endothall X (45) Endrin X (46) Glyphosate X (47) Hexachlorobenzene X (48) Hexachlorocyclopentadiene X X (49) Oxamyl (Vydate) X (50) Picloram X (51) Simazine X (52) 1,2,4-Trichlorobenzene X X (53) 1,1,2-Trichloroethane X X (54) 2,3,7,8-TCDD (Dioxin) X 1. Packed Tower Aeration. 2. Granular Activated Carbon. 3. Oxidation (Chlorination or Ozonation) Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 39 ------- SUMMARY OF FEDERAL REQUIREMENT FEDERAL CITATION EXPLANATION OF STATE POLICIES AND PROCEDURES Table 3 to Paragraph (a)—List of Small System Compliance Technologies (SSCTs)1 for PFAS Listed in § 141.61(c) 40 CFR 142.62(a) Small system compliance technologies Affordable for listed small system categories2 Anion Exchange All size categories. GAC All size categories. Reverse Osmosis,3 Nanofiltration3 3,301-10,000. 1. Section 1412(b)(4)(E)(ii) of SDWA specifies that SSCTs must be affordable and technically feasible for small systems. 2. The Act (ibid.) specifies three categories of small systems: (i) those serving 25 or more, but fewer than 501, (ii) those serving more than 500, but fewer than 3,301, and (iii) those serving more than 3,300, but fewer than 10,001. 3. Technologies reject a large volume of water and may not be appropriate for areas where water quantity may be an issue. Control of Per- and Polyfluoroalkyl Substances (PFAS) - Primacy Crosswalk 40 ------- |