Cal. Code Regs. Tit. 22, § 64534.6 - Disinfection Byproduct Precursors Monitoring

(a) Systems that use approved surface water and conventional filtration treatment (as defined in section 64651.23) shall take one paired TOC sample (source water and treated water) and one source water alkalinity sample per month per treatment plant at a time representative of normal operating conditions and influent water quality. TOC and alkalinity in the source water shall be monitored prior to any treatment and at the same time as TOC monitoring in the treated water. TOC in the treated water shall be monitored no later than the point of combined filter effluent turbidity monitoring and shall be representative of the treated water.

(b) Systems using approved surface water with an annual average treated water TOC of less than 2.0 mg/L for two consecutive years, or less than 1.0 mg/L for one year, may reduce monitoring for both TOC and alkalinity to one paired sample and one source water alkalinity sample per plant per quarter. The system shall revert to monitoring pursuant to subsection (a) in the first month following the quarter that the annual average treated water TOC is equal to or greater than 2.0 mg/L.

(c) Systems using approved surface water and not monitoring pursuant to subsection (a) or (b):

(1) To qualify for reduced TTHM and HAA5 monitoring pursuant to table 64534.2-B or 64534.2-D, shall take monthly TOC samples every 30 days at a location prior to any treatment; and

(2) Once qualified for reduced TTHM and HAA5 monitoring pursuant to table 64534.2-B or 64534.2-D, may reduce source water TOC monitoring to quarterly TOC samples taken every 90 days at a location prior to any treatment. The system shall revert to source water TOC monitoring pursuant to paragraph (1) in the first month following the quarter that the annual average source water TOC is greater than 4.0 mg/L.

Notes

Cal. Code Regs. Tit. 22, § 64534.6

1. New section filed 5-18-2006; operative 6-17-2006 (Register 2006, No. 20).
2. Amendment of section heading, new subsections (c)-(c)(2) and amendment of NOTE filed 5-22-2012; operative 6-21-2012 (Register 2012, No. 21).

Note: Authority cited: Sections 116350, 116375, 131052 and 131200, Health and Safety Code. Reference: Sections 116350, 116385 and 116555, Health and Safety Code.

1. New section filed 5-18-2006; operative 6-17-2006 (Register 2006, No. 20).
2. Amendment of section heading, new subsections (c)-(c)(2) and amendment of Note filed 5-22-2012; operative 6-21-2012 (Register 2012, No. 21).