TITLE 35: ENVIRONMENTAL PROTECTION SUBTITLE F: PUBLIC WATER SUPPLIES CHAPTER I: POLLUTION CONTROL BOARD PART 611 PRIMARY DRINKING WATER STANDARDS The General Assembly's Illinois Administrative Code database includes only those rulemakings that have been permanently adopted. This menu will point out the Sections on which an emergency rule (valid for a maximum of 150 days, usually until replaced by a permanent rulemaking) exists. The emergency rulemaking is linked through the notation that follows the Section heading in the menu. View Entire Part SUBPART A: GENERAL Section 611.100 Purpose, Scope, and Applicability Section 611.101 Definitions Section 611.102 Incorporations by Reference Section 611.103 Severability Section 611.105 Electronic Reporting Section 611.107 Agency Inspection of PWS Facilities (Repealed) Section 611.108 Delegation to Local Government Section 611.109 Enforcement Section 611.110 Special Exception Permits Section 611.111 Relief Equivalent to SDWA Section 1415(a) Variances Section 611.112 Relief Equivalent to SDWA Section 1416 Exemptions Section 611.113 Alternative Treatment Techniques Section 611.114 Siting Requirements Section 611.115 Source Water Quantity (Repealed) Section 611.120 Effective Dates (Repealed) Section 611.121 Maximum Contaminant Levels Section 611.125 Fluoridation Requirement Section 611.126 Using Lead-Free Pipes, Fittings, Fixtures, Solder, and Flux for Drinking Water Section 611.130 Special Requirements for Certain Variances and Adjusted Standards Section 611.131 Relief Equivalent to SDWA Section 1415(e) Small System Variance Section 611.160 Composite Correction Program Section 611.161 Case-by-Case Reduced Subpart Y Monitoring for Wholesale and Consecutive Systems SUBPART B: FILTRATION AND DISINFECTION Section 611.201 Requiring a Demonstration Section 611.202 Procedures for Agency Determinations (Repealed) Section 611.211 Filtration Required Section 611.212 Groundwater under Direct Influence of Surface Water Section 611.213 No Method of HPC Analysis Section 611.220 General Requirements Section 611.230 Filtration Effective Dates (Repealed) Section 611.231 Source Water Limitation Section 611.232 Site-Specific Conditions (Repealed) Section 611.233 Treatment Technique Violations Section 611.240 Disinfection Section 611.241 Unfiltered PWSs (Repealed) Section 611.242 Filtered PWSs Section 611.250 Filtration Section 611.261 Unfiltered PWSs: Reporting and Recordkeeping Section 611.262 Filtered PWSs: Reporting and Recordkeeping Section 611.271 Protection during Repair Work (Repealed) Section 611.272 Disinfection Following Repair (Repealed) Section 611.276 Recycle Provisions SUBPART C: USE OF NON-CENTRALIZED TREATMENT DEVICES Section 611.280 Point-of-Entry Devices Section 611.290 Point-of-Use Devices or Bottled Water SUBPART D: TREATMENT TECHNIQUES Section 611.295 General Requirements Section 611.296 Acrylamide and Epichlorohydrin Section 611.297 Corrosion Control (Repealed) SUBPART F: MAXIMUM CONTAMINANT LEVELS (MCLs) AND MAXIMUM RESIDUAL DISINFECTANT LEVELS (MRDLs) Section 611.300 State-Only MCLs for Inorganic Chemical Contaminants Section 611.301 Revised MCLs for Inorganic Chemical Contaminants Section 611.310 State-Only Maximum Contaminant Levels (MCLs) for Organic Chemical Contaminants Section 611.311 Revised MCLs for Organic Chemical Contaminants Section 611.312 Maximum Contaminant Levels (MCLs) for Disinfection Byproducts (DBPs) Section 611.313 Maximum Residual Disinfectant Levels (MRDLs) Section 611.320 Turbidity (Repealed) Section 611.325 Microbiological Contaminants Section 611.330 Maximum Contaminant Levels for Radionuclides Section 611.331 Beta Particle and Photon Radioactivity (Repealed) SUBPART G: LEAD AND COPPER Section 611.350 General Requirements Section 611.351 Applicability of Corrosion Control Section 611.352 Corrosion Control Treatment Section 611.353 Source Water Treatment Section 611.354 Lead Service Line Inventory and Replacing Lead Service Lines Section 611.355 Public Education and Supplemental Monitoring and Mitigation Section 611.356 Tap Water Monitoring for Lead and Copper Section 611.357 Monitoring for Water Quality Parameters Section 611.358 Monitoring for Lead and Copper in Source Water Section 611.359 Analytical Methods Section 611.360 Reporting Section 611.361 Recordkeeping Section 611.362 Monitoring for Lead in Schools and Child Care Facilities Section 611.363 Small Supplier Compliance Flexibility SUBPART I: DISINFECTANT RESIDUALS, DISINFECTION BYPRODUCTS, AND DISINFECTION BYPRODUCT PRECURSORS Section 611.380 General Requirements Section 611.381 Analytical Requirements Section 611.382 Monitoring Requirements Section 611.383 Compliance Requirements Section 611.384 Reporting and Recordkeeping Requirements Section 611.385 Treatment Technique for Control of Disinfection Byproduct (DBP) Precursors SUBPART K: GENERAL MONITORING AND ANALYTICAL REQUIREMENTS Section 611.480 Alternative Analytical Techniques Section 611.490 Certified Laboratories Section 611.491 Laboratory Testing Equipment (Repealed) Section 611.500 Consecutive PWSs Section 611.510 Special Monitoring for Unregulated Contaminants (Repealed) SUBPART L: MICROBIOLOGICAL MONITORING AND ANALYTICAL REQUIREMENTS Section 611.521 Routine Coliform Monitoring (Repealed) Section 611.522 Repeat Coliform Monitoring (Repealed) Section 611.523 Invalidation of Total Coliform Samples (Repealed) Section 611.524 Sanitary Surveys (Repealed) Section 611.525 Fecal Coliform and E. Coli Testing (Repealed) Section 611.526 Analytical Methodology (Repealed) Section 611.527 Response to Violation (Repealed) Section 611.528 Transition from Subpart L to Subpart AA Requirements (Repealed) Section 611.531 Analytical Requirements Section 611.532 Unfiltered PWSs Section 611.533 Filtered PWSs SUBPART M: TURBIDITY MONITORING AND ANALYTICAL REQUIREMENTS Section 611.560 Turbidity (Repealed) SUBPART N: INORGANIC MONITORING AND ANALYTICAL REQUIREMENTS Section 611.591 Violation of a State-Only MCL Section 611.592 Frequency of State Monitoring Section 611.600 Applicability Section 611.601 Monitoring Frequency Section 611.602 Asbestos Monitoring Frequency Section 611.603 Inorganic Monitoring Frequency Section 611.604 Nitrate Monitoring Section 611.605 Nitrite Monitoring Section 611.606 Confirmation Samples Section 611.607 More Frequent Monitoring and Confirmation Sampling Section 611.608 Additional Optional Monitoring Section 611.609 Determining Compliance Section 611.610 Inorganic Monitoring Times Section 611.611 Inorganic Analysis Section 611.612 Monitoring Requirements for Old Inorganic MCLs Section 611.630 Special Monitoring for Sodium Section 611.631 Special Monitoring for Inorganic Chemicals (Repealed) SUBPART O: ORGANIC MONITORING AND ANALYTICAL REQUIREMENTS Section 611.640 Definitions Section 611.641 State-Only MCLs Section 611.645 Analytical Methods for Organic Chemical Contaminants Section 611.646 Phase I, Phase II, and Phase V Volatile Organic Contaminants Section 611.647 Sampling for Phase I Volatile Organic Contaminants (Repealed) Section 611.648 Phase II, Phase IIB, and Phase V Synthetic Organic Contaminants Section 611.650 Monitoring for 36 Contaminants (Repealed) Section 611.657 Analytical Methods for 36 Contaminants (Repealed) Section 611.658 Special Monitoring for Organic Chemicals (Repealed) SUBPART P: THM MONITORING AND ANALYTICAL REQUIREMENTS Section 611.680 Sampling, Analytical, and other Requirements (Repealed) Section 611.683 Reduced Monitoring Frequency (Repealed) Section 611.684 Averaging (Repealed) Section 611.685 Analytical Methods (Repealed) Section 611.686 Modification to System (Repealed) Section 611.687 Sampling for Maximum THM Potential (Repealed) Section 611.688 Applicability Dates (Repealed) SUBPART Q: RADIOLOGICAL MONITORING AND ANALYTICAL REQUIREMENTS Section 611.720 Analytical Methods Section 611.731 Gross Alpha Section 611.732 Beta Particle and Photon Radioactivity Section 611.733 General Monitoring and Compliance Requirements SUBPART R: ENHANCED FILTRATION AND DISINFECTION: SYSTEMS THAT SERVE 10,000 OR MORE PEOPLE Section 611.740 General Requirements Section 611.741 Standards for Filtration Section 611.742 Disinfection Profiling and Benchmarking Section 611.743 Filtration Section 611.744 Filtration Sampling Requirements Section 611.745 Reporting and Recordkeeping Requirements SUBPART S: GROUNDWATER RULE Section 611.800 General Requirements and Applicability Section 611.801 Sanitary Surveys for GWS Suppliers Section 611.802 Groundwater Source Microbial Monitoring and Analytical Methods Section 611.803 Treatment Technique Requirements for GWS Suppliers Section 611.804 Treatment Technique Violations for GWS Suppliers Section 611.805 Reporting and Recordkeeping for GWS Suppliers SUBPART T: REPORTING AND RECORDKEEPING Section 611.830 Applicability Section 611.831 Monthly Operating Report (Repealed) Section 611.832 Notice by Agency (Repealed) Section 611.833 Cross Connection Reporting (Repealed) Section 611.840 Reporting Section 611.851 Reporting MCL, MRDL, and other Violations (Repealed) Section 611.852 Reporting other Violations (Repealed) Section 611.853 Notice to New Billing Units (Repealed) Section 611.854 General Content of Public Notice (Repealed) Section 611.855 Mandatory Health Effects Language (Repealed) Section 611.856 Fluoride Notice (Repealed) Section 611.858 Fluoride Secondary Standard (Repealed) Section 611.860 Record Maintenance Section 611.870 List of 36 Contaminants (Repealed) SUBPART U: CONSUMER CONFIDENCE REPORTS Section 611.881 Purpose and Applicability Section 611.882 Compliance Dates Section 611.883 Content of the Reports Section 611.884 Required Additional Health Information Section 611.885 Report Delivery and Recordkeeping SUBPART V: PUBLIC NOTIFICATION OF DRINKING WATER VIOLATIONS Section 611.901 General Public Notification Requirements Section 611.902 Tier 1 Public Notice: Form, Manner, and Frequency of Notice Section 611.903 Tier 2 Public Notice: Form, Manner, and Frequency of Notice Section 611.904 Tier 3 Public Notice: Form, Manner, and Frequency of Notice Section 611.905 Content of the Public Notice Section 611.906 Notice to New Billing Units or New Customers Section 611.907 Special Notice of the Availability of Unregulated Contaminant Monitoring Results Section 611.908 Special Notice for Exceedance of the Fluoride Secondary Standard Section 611.909 Special Notice for Nitrate Exceedances above the MCL by a Non-Community Water System Section 611.910 Notice by the Agency on Behalf of a PWS Section 611.911 Special Notice for Cryptosporidium SUBPART W: INITIAL DISTRIBUTION SYSTEM EVALUATIONS Section 611.920 General Requirements Section 611.921 Standard Monitoring Section 611.922 System-Specific Studies Section 611.923 40/30 Certification Section 611.924 Very Small System Waivers Section 611.925 Subpart Y Compliance Monitoring Location Recommendations SUBPART X: ENHANCED FILTRATION AND DISINFECTION – SYSTEMS SERVING FEWER THAN 10,000 PEOPLE Section 611.950 General Requirements Section 611.951 Finished Water Reservoirs Section 611.952 Additional Watershed Control Requirements for Unfiltered Systems Section 611.953 Disinfection Profile Section 611.954 Disinfection Benchmark Section 611.955 Combined Filter Effluent Turbidity Limits Section 611.956 Individual Filter Turbidity Requirements Section 611.957 Reporting and Recordkeeping Requirements SUBPART Y: STAGE 2 DISINFECTION BYPRODUCTS REQUIREMENTS Section 611.970 General Requirements Section 611.971 Routine Monitoring Section 611.972 Subpart Y Monitoring Plan Section 611.973 Reduced Monitoring Section 611.974 Additional Requirements for Consecutive Systems Section 611.975 Conditions Requiring Increased Monitoring Section 611.976 Operational Evaluation Levels Section 611.977 Requirements for Remaining on Reduced TTHM and HAA5 Monitoring Based on Subpart I Results Section 611.978 Requirements for Remaining on Increased TTHM and HAA5 Monitoring Based on Subpart I Results Section 611.979 Reporting and Recordkeeping Requirements SUBPART Z: ENHANCED TREATMENT FOR CRYPTOSPORIDIUM Section 611.1000 General Requirements Section 611.1001 Source Water Monitoring Requirements: Source Water Monitoring Section 611.1002 Source Water Monitoring Requirements: Sampling Schedules Section 611.1003 Source Water Monitoring Requirements: Sampling Locations Section 611.1004 Source Water Monitoring Requirements: Analytical Methods Section 611.1005 Source Water Monitoring Requirements: Approved Laboratories Section 611.1006 Source Water Monitoring Requirements: Reporting Source Water Monitoring Results Section 611.1007 Source Water Monitoring Requirements: Grandfathering Previously Collected Data Section 611.1008 Disinfection Profiling and Benchmarking Requirements: Requirements When Making a Significant Change in Disinfection Practice Section 611.1009 Disinfection Profiling and Benchmarking Requirements: Developing the Disinfection Profile and Benchmark Section 611.1010 Treatment Technique Requirements: Bin Classification for Filtered System Suppliers Section 611.1011 Treatment Technique Requirements: Filtered System Additional Cryptosporidium Treatment Requirements Section 611.1012 Treatment Technique Requirements: Unfiltered System Cryptosporidium Treatment Requirements Section 611.1013 Treatment Technique Requirements: Schedule for Compliance with Cryptosporidium Treatment Requirements Section 611.1014 Treatment Technique Requirements: Requirements for Uncovered Finished Water Storage Facilities Section 611.1015 Requirements for Microbial Toolbox Components: Microbial Toolbox Options for Meeting Cryptosporidium Treatment Requirements Section 611.1016 Requirements for Microbial Toolbox Components: Source Toolbox Components Section 611.1017 Requirements for Microbial Toolbox Components: Pre-Filtration Treatment Toolbox Components Section 611.1018 Requirements for Microbial Toolbox Components: Treatment Performance Toolbox Components Section 611.1019 Requirements for Microbial Toolbox Components: Additional Filtration Toolbox Components Section 611.1020 Requirements for Microbial Toolbox Components: Inactivation Toolbox Components Section 611.1021 Reporting and Recordkeeping Requirements: Reporting Requirements Section 611.1022 Reporting and Recordkeeping Requirements: Recordkeeping Requirements Section 611.1023 Requirements to Respond to Significant Deficiencies Identified in Sanitary Surveys Performed by USEPA or the Agency SUBPART AA: REVISED TOTAL COLIFORM RULE Section 611.1051 General Section 611.1052 Analytical Methods and Laboratory Certification Section 611.1053 General Monitoring Requirements for all PWSs Section 611.1054 Routine Monitoring Requirements for Non-CWSs That Serve 1,000 or Fewer People Using Only Groundwater Section 611.1055 Routine Monitoring Requirements for CWSs That Serve 1,000 or Fewer People Using Only Groundwater Section 611.1056 Routine Monitoring Requirements for Subpart B Systems That Serve 1,000 or Fewer People Section 611.1057 Routine Monitoring Requirements for PWSs That Serve More Than 1,000 People Section 611.1058 Repeat Monitoring and E. coli Requirements Section 611.1059 Coliform Treatment Technique Triggers and Assessment Requirements for Protection Against Potential Fecal Contamination Section 611.1060 Violations Section 611.1061 Reporting and Recordkeeping SUBPART AG: INTERIM LEAD AND COPPER RULES Section 611.1350 General Requirements Section 611.1351 Applicability of Corrosion Control Section 611.1352 Corrosion Control Treatment Section 611.1353 Source Water Treatment Section 611.1354 Lead Service Line Replacement Section 611.1355 Public Education and Supplemental Monitoring Section 611.1356 Tap Water Monitoring for Lead and Copper Section 611.1357 Monitoring for Water Quality Parameters Section 611.1358 Monitoring for Lead and Copper in Source Water Section 611.1359 Analytical Methods Section 611.1360 Reporting Section 611.1361 Recordkeeping Section 611.APPENDIX A Regulated Contaminants Section 611.APPENDIX B Percent Inactivation of G. Lamblia Cysts Section 611.APPENDIX C Common Names of Organic Chemicals Section 611.APPENDIX D Defined Substrate Method for the Simultaneous Detection of Total Coliforms and Escherichia Coli from Drinking Water (Repealed) Section 611.APPENDIX E Mandatory Lead Public Education Information for Community Water Systems Section 611.APPENDIX F Mandatory Lead Public Education Information for Non-Transient Non-Community Water Systems Section 611.APPENDIX G NPDWR Violations and Situations Requiring Public Notice Section 611.APPENDIX H Standard Health Effects Language for Public Notification Section 611.APPENDIX I Acronyms Used in Public Notification Regulation Section 611.TABLE A Total Coliform Monitoring Frequency (Repealed) Section 611.TABLE B Fecal or Total Coliform Density Measurements Section 611.TABLE C Frequency of RDC Measurement Section 611.TABLE D Number of Lead and Copper Monitoring Sites Section 611.TABLE E Lead and Copper Monitoring Start Dates (Repealed) Section 611.TABLE F Number of Water Quality Parameter Sampling Sites Section 611.TABLE G Summary of Section 611.357 Monitoring Requirements for Water Quality Parameters (Repealed) Section 611.TABLE H CT Values (mg·min/l) for Cryptosporidium Inactivation by Chlorine Dioxide Section 611.TABLE I CT Values (mg·min/l) for Cryptosporidium Inactivation by Ozone Section 611.TABLE J UV Dose Table for Cryptosporidium, Giardia lamblia, and Virus Inactivation Credit Section 611.TABLE R Radionuclide Conversion Factors Section 611.TABLE Z Federal Effective Dates

AUTHORITY: Implementing Sections 7.2, 17, and 17.5 and authorized by Section 27 of the Environmental Protection Act [415 ILCS 5/7.2, 17, 17.5, and 27].

SOURCE: Adopted in R88-26 at 14 Ill. Reg. 16517, effective September 20, 1990; amended in R90-21 at 14 Ill. Reg. 20448, effective December 11, 1990; amended in R90-13 at 15 Ill. Reg. 1562, effective January 22, 1991; amended in R91-3 at 16 Ill. Reg. 19010, effective December 1, 1992; amended in R92-3 at 17 Ill. Reg. 7796, effective May 18, 1993; amended in R93-1 at 17 Ill. Reg. 12650, effective July 23, 1993; amended in R94-4 at 18 Ill. Reg. 12291, effective July 28, 1994; amended in R94-23 at 19 Ill. Reg. 8613, effective June 20, 1995; amended in R95-17 at 20 Ill. Reg. 14493, effective October 22, 1996; amended in R98-2 at 22 Ill. Reg. 5020, effective March 5, 1998; amended in R99-6 at 23 Ill. Reg. 2756, effective February 17, 1999; amended in R99-12 at 23 Ill. Reg. 10348, effective August 11, 1999; amended in R00-8 at 23 Ill. Reg. 14715, effective December 8, 1999; amended in R00-10 at 24 Ill. Reg. 14226, effective September 11, 2000; amended in R01-7 at 25 Ill. Reg. 1329, effective January 11, 2001; amended in R01-20 at 25 Ill. Reg. 13611, effective October 9, 2001; amended in R02-5 at 26 Ill. Reg. 3522, effective February 22, 2002; amended in R03-4 at 27 Ill. Reg. 1183, effective January 10, 2003; amended in R03-15 at 27 Ill. Reg. 16447, effective October 10, 2003; amended in R04-3 at 28 Ill. Reg. 5269, effective March 10, 2004; amended in R04-13 at 28 Ill. Reg. 12666, effective August 26, 2004; amended in R05-6 at 29 Ill. Reg. 2287, effective January 28, 2005; amended in R06-15 at 30 Ill. Reg. 17004, effective October 13, 2006; amended in R07-2/R07-11 at 31 Ill. Reg. 11757, effective July 27, 2007; amended in R08-7/R08-13 at 33 Ill. Reg. 633, effective December 30, 2008; amended in R10-1/R10-17/R11-6 at 34 Ill. Reg. 19848, effective December 7, 2010; amended in R12-4 at 36 Ill. Reg. 7110, effective April 25, 2012; amended in R13-2 at 37 Ill. Reg. 1978, effective February 4, 2013; amended in R14-8 at 38 Ill. Reg. 3608, effective January 27, 2014; amended in R14-9 at 38 Ill. Reg. 9792, effective April 21, 2014; amended in R15-6 at 39 Ill. Reg. 3713, effective February 24, 2015; amended in R15-23 at 39 Ill. Reg. 15144, effective November 9, 2015; amended in R16-4 at 39 Ill. Reg. 15352, effective November 13, 2015; amended in R17-12 at 42 Ill. Reg. 1140, effective January 4, 2018; amended in R18-9 at 42 Ill. Reg. 9316, effective May 29, 2018; amended in R18-17 at 43 Ill. Reg. 8206, effective July 26, 2019; amended in R19-16 at 44 Ill. Reg. 6996, effective April 17, 2020; amended in R18-26 at 47 Ill. Reg. 7556, effective May 16, 2023; amended in R21-10/R22-2 at 47 Ill. Reg. 16486, effective November 2, 2023; amended in R23-9 at 47 Ill. Reg. 18996, effective December 7, 2023.