- Chapter 20-1 - AIR QUALITY - GENERAL RULES
- Chapter 20-2 - AIR QUALITY - GENERAL AND NON-ATTAINMENT AREA PERMITS
- Chapter 20-3 - AIR QUALITY - OPERATING PERMITS AND ACID RAIN PROGRAMS
- Chapter 20-4 - AIR QUALITY - AMBIENT MONITORING, EMERGENCY PROCEDURES, AND CHEMICAL ACCIDENT PREVENTION
- Chapter 20-5 - AIR QUALITY - SOURCE MONITORING AND TESTING
- Chapter 20-6 - AIR QUALITY - PARTICULATES
- Chapter 20-7 - AIR QUALITY - VOLATILE ORGANIC COMPOUNDS AND HAZARDOUS AIR POLLUTANTS
- Chapter 20-8 - AIR QUALITY - ASBESTOS, SULFUR, NITROGEN OXIDES, AND LEAD, AND CARBON DIOXIDE
- Chapter 20-9 - AIR QUALITY - MOTOR VEHICULAR POLLUTANTS, LEAD, ODORS, AND NUISANCE POLLUTANTS
- Chapter 20-10 - AIR QUALITY - NITROGEN OXIDES EMISSIONS BUDGET PROGRAM
- Chapter 20-12 - DEMAND RESPONSE GENERATING SOURCES
- Chapter 20-14 - AIR TOXICS AND HAZARDOUS AIR POLLUTANTS
- Chapter 20-15 - AIR QUALITY - GENERAL AND TRANSPORTATION CONFORMITY
- Chapter 20-21 - SMOKING REGULATIONS
- Chapter 20-22 - PESTICIDE CONTROL - GENERAL RULES
- Chapter 20-23 - PESTICIDE CONTROL - APPLICATORS
- Chapter 20-24 - PESTICIDE CONTROL - OPERATORS
- Chapter 20-25 - PESTICIDE CONTROL - ADMINISTRATION AND ENFORCEMENT
- Chapter 20-26 - FIRE-STANDARD-COMPLIANT CIGARETTES
- Chapter 20-27 - NOISE CONTROL
- Chapter 20-28 - MAXIMUM NOISE LEVELS
- Chapter 20-29 - NOISE MEASURING TEST PROCEDURES
- Chapter 20-31 - FLOOD HAZARD RULES
- Chapter 20-32 - MOLD AND RADON LICENSURE AND CERTIFICATION
- Chapter 20-33 - REGULATION OF LEAD-BASED PAINT ACTIVITIES
- Chapter 20-34 - ENERGY CONSERVATION DEMONSTRATION AWARDS PROGRAM
- Chapter 20-35 - GREEN BUILDING REQUIREMENTS
- Chapter 20-36 - ENERGY ASSISTANCE AND CONSERVATION PROGRAMS
- Chapter 20-38 - LEAD PIPE REPLACEMENT ASSISTANCE PROGRAM ELIGIBILITY DETERMINATIONS
- Chapter 20-39 - BATTERY STEWARDSHIP
- Chapter 20-40 - PAINT STEWARDSHIP
- Chapter 20-41 - ELECTRONICS STEWARDSHIP
- Chapter 20-42 - HAZARDOUS WASTE MANAGEMENT - STANDARDS FOR THE MANAGEMENT OF HAZARDOUS WASTE AND USED OIL
- Chapter 20-43 - HAZARDOUS WASTE MANAGEMENT - ADMINISTRATION AND ENFORCEMENT
- Chapter 20-55 - UNDERGROUND STORAGE TANKS - GENERAL PROVISIONS
- Chapter 20-56 - UNDERGROUND STORAGE TANKS - NOTIFICATION, REGISTRATION, RECORDKEEPING, AND PUBLIC INFORMATION
- Chapter 20-57 - UNDERGROUND STORAGE TANKS - NEW TANK PERFORMANCE STANDARDS
- Chapter 20-58 - UNDERGROUND STORAGE TANKS - UPGRADES OF EXISTING USTS
- Chapter 20-59 - UNDERGROUND STORAGE TANKS - OPERATION AND MAINTENANCE OF USTS
- Chapter 20-60 - UNDERGROUND STORAGE TANKS - RELEASE DETECTION
- Chapter 20-61 - UNDERGROUND STORAGE TANKS - CLOSURE
- Chapter 20-62 - UNDERGROUND STORAGE TANKS - REPORTING OF RELEASES, INVESTIGATION, CONFIRMATION, ASSESSMENT, AND CORRECTIVE ACTION
- Chapter 20-63 - UNDERGROUND STORAGE TANKS - RIGHT OF ENTRY FOR INSPECTIONS MONITORING, TESTING AND CORRECTIVE ACTION
- Chapter 20-64 - UNDERGROUND STORAGE TANKS - CORRECTIVE ACTION BY THE DISTRICT AND COST RECOVERY
- Chapter 20-65 - UNDERGROUND STORAGE TANKS - LICENSING, CERTIFICATION, OPERATOR REQUIREMENTS, AND OPERATOR TRAINING
- Chapter 20-66 - UNDERGROUND STORAGE TANKS - ENFORCEMENT
- Chapter 20-67 - UNDERGROUND STORAGE TANKS - FINANCIAL RESPONSIBILITY
- Chapter 20-70 - UNDERGROUND STORAGE TANKS - DEFINITIONS
- Chapter 20-72 - ENVIRONMENTAL POLICY ACT REGULATIONS