Figure: 30 TAC §290.117(e)(5)

Reduced Water Quality Parameter (WQP) Entry Point and Distribution Monitoring
Monitoring Period Reduced WQP List Location  Frequency
Reduced
monitoring
pH, alkalinity, orthophosphate or
silica1, calcium2
Reduced number of
distribution sites
 Quarterly,
 annually5, or
 every 3 years6
pH, alkalinity dosage rate and
concentration3, inhibitor dosage
rate and inhibitor residual4
All entry point(s)  Every two weeks

1Orthophosphate must be measured if an inhibitor containing a phosphate compound is used. Silica must be measured if an inhibitor containing silicate compound is used.
2Calcium must be measured if calcium carbonate stabilization is used as part of corrosion control.
3Alkalinity must be measured if alkalinity is adjusted as part of corrosion control.
4Inhibitor dosage rates and inhibitor residual concentrations (orthophosphate or silica) must be measured if an inhibitor is used.
5In accordance with subparagraph (B) of this paragraph, the executive director may allow a system to sample WQPs in distribution annually if it has operated within approved Optimal Water Quality Parameters (OWQPs) three consecutive years of monitoring.
6In accordance with subparagraph (C) of this paragraph, the executive director may allow systems to sample WQP in distribution once every three years if the system has operated within approve OWQP ranges during three consecutive years of annual monitoring. The executive director may allow a system to sample WQPs in the distribution once every three years if it has maintained 90th percentile lead levels less than or equal to 0.005 milligrams per liter (mg/L), 90th percentile copper levels less than or equal to 0.65 mg/L, and has operated within approved OWQP ranges during two consecutive six-month monitoring periods.