Title 22 Chapter 15

Chapter 15 is the largest and most important chapter in Title 22 for the T-5 exam. It is where California implements the federal drinking water standards and adds its own, more stringent requirements. Every MCL table, every monitoring frequency, every operator certification requirement that applies to your plant traces back to this chapter.

I am not going to pretend this is exciting reading. It is a reference chapter, and studying it feels like studying a regulatory encyclopedia. However, the exam draws heavily from it, and knowing where to find things within Chapter 15 is as important as knowing the specific numbers.

I organized this guide by article, the same way the chapter itself is organized, and I highlighted the MCLs and requirements that are most likely to appear on the exam. If a value is California-specific (more stringent than the federal standard), I called it out. Those are the ones the exam tests most frequently, because they are the ones that differentiate California operators from everyone else.

What Does Chapter 15 Cover?

Chapter 15 spans sections 64400 through 64483 and is the core drinking water quality chapter for all public water systems in California. It covers system definitions, MCLs for inorganic chemicals, radioactivity, and organic chemicals, monitoring requirements, treatment techniques, secondary standards, public notification, consumer confidence reports, and recordkeeping.

Several articles within Chapter 15 are covered in detail in their own study guides on this site. The RTCR requirements (Article 3, sections 64421 through 64427), the Ground Water Rule (Article 3.5, section 64430), and public notification (Article 18, sections 64463 through 64465) all have dedicated guides. This guide focuses on the MCL tables, facility classification, and California-specific requirements that are not covered elsewhere.

What Are the California-Specific Inorganic Chemical MCLs?

These MCLs are established under Article 4 (sections 64431 through 64432). Several are more stringent than the federal standards. The California-specific values are the ones the exam is most likely to test, because they demonstrate California's use of primacy to exceed federal minimums.

Perchlorate and hexavalent chromium are entirely California-specific. There are no federal MCLs for these contaminants. The fluoride MCL is half the federal standard (2.0 versus 4.0 mg/L), reflecting California's more conservative approach.

Inorganic chemicals are monitored at each source or entry point. Monitoring frequency depends on system type and compliance history. Nitrate has a special provision: if the MCL is exceeded, a confirmation sample must be collected within 24 hours and Tier 1 public notification is required.

What Are the Radioactivity MCLs?

Radioactivity MCLs are established under Article 5 (sections 64442 through 64443). These apply at each source or representative entry point and are monitored once per compliance period, which ranges from every 4 to 9 years.

The long monitoring intervals reflect the fact that radioactivity in ground water sources tends to be stable over time. However, new sources or changed conditions can alter these levels, which is why periodic monitoring continues.

What Are the Key Organic Chemical MCLs?

Article 5.5 (sections 64444 through 64445) covers MCLs for more than 60 organic chemicals. These are the values most likely to appear on the T-5 exam, including the California-specific standards.

The 1,2,3-TCP MCL at 5 parts per trillion is one of the lowest MCLs in the entire regulatory framework. It is entirely California-specific and frequently tested.

Ground water sources are monitored every compliance period. Surface water sources are monitored annually. Waivers from monitoring may be available based on vulnerability assessments.

What Are the Treatment Technique Requirements?

Article 14 (section 64448) establishes treatment techniques for two chemicals that cannot be effectively monitored in finished water: acrylamide and epichlorohydrin. These are not MCLs. They are limits on the amount of monomer residual allowed in treatment chemicals.

Acrylamide is limited to 0.05% monomer in polyacrylamide polymers dosed at 1 mg/L (or the equivalent combination). Epichlorohydrin is limited to 0.01% residual in products dosed at 20 mg/L (or the equivalent). Systems using these chemicals must certify compliance to the State Board annually.

How Do California's Secondary Standards Differ from Federal?

This is a critical distinction for the T-5 exam. At the federal level, secondary drinking water standards are non-enforceable guidelines for aesthetic qualities. In California, secondary standards under Article 16 (section 64449) are enforceable.

The three-tier system for TDS, chloride, and sulfate (recommended, upper, short-term) is unique to California and is testable. The recommended level is the target. The upper level is acceptable. The short-term level is allowed only temporarily.

How Does Facility Classification and Operator Certification Work?

Facility classification under section 64413.1 uses a point system based on source complexity, treatment processes, and population served. The total points determine the facility grade from T1 through T5 for treatment and D1 through D5 for distribution.

The certification requirement is direct: shift operators must hold a certificate at or above the facility grade. The chief operator must also hold a certificate at or above the facility grade. If you are studying for the T-5, it is because you operate or plan to operate a T-5 classified facility, which represents the most complex treatment systems in the state.

All water quality samples must be analyzed by a State-certified laboratory. Field personnel collecting samples must be trained in proper collection techniques.

What Are the Consumer Confidence Report Requirements?

Article 20 (sections 64480 through 64483) requires community water systems to produce an annual Consumer Confidence Report (CCR) and deliver it to customers by July 1 for the previous calendar year.

The CCR must include source water information, all detected contaminants with MCL comparisons, any violations that occurred, information about variances or exemptions, and educational material about drinking water quality. A copy must be retained for 3 years.

Only community water systems are required to produce CCRs. Noncommunity systems are not subject to this requirement.

Chapter 15 is the regulatory backbone of California's drinking water program. It covers more ground than any other chapter in Title 22, and the T-5 exam draws from it heavily. The California-specific MCLs, the enforceable secondary standards, and the facility classification system are the areas where California diverges from federal requirements, and those are the areas the exam focuses on.

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Frequently Asked Questions

What California-specific MCLs should T-5 candidates know?

California has several MCLs more stringent than federal standards. Key CA-specific values include perchlorate at 0.006 mg/L (no federal MCL), hexavalent chromium at 0.010 mg/L (no separate federal MCL), 1,2,3-TCP at 0.000005 mg/L (no federal MCL), fluoride at 2.0 mg/L (federal is 4.0), and barium at 1.0 mg/L (federal is 2.0). These reflect California's use of primacy to set standards exceeding federal minimums.

What determines the required operator grade for a water treatment facility?

Facility classification uses a point system based on source complexity, treatment processes, and population served. Total points determine the facility grade (T1 through T5 for treatment, D1 through D5 for distribution). Shift operators must hold a certificate at or above the facility grade, as must the chief operator.

Are secondary standards enforceable in California?

Yes. Unlike federal secondary standards, which are non-enforceable guidelines, California's secondary standards under section 64449 are enforceable. These include standards for iron (0.3 mg/L), manganese (0.05 mg/L), color (15 units), odor (3 threshold units), TDS, and other aesthetic parameters. A system can be cited for exceeding these standards in California.