Table Z
Reduced Stage 2 Monitoring Frequency and Number of Sites
Source Water Type | Population Size Category | Monitoring Frequency | Distribution System Monitoring Location Total per Monitoring Period |
Surface Water or GWUDI | less than 500 | Annual | Monitoring may not be reduced. |
500 to 3,300 | Annual | 1 TTHM and 1 HAA5 at the respective locations and quarters with the highest individual DBP; 1 dual sample set per year if the highest TTHM and HAA5 measurements occurred at the same location and quarter. | |
3,301 to 9,999 | Annual | 2 dual sample sets: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement. | |
10,000 to 49,999 | quarterly | 2 dual sample sets at the locations with the highest TTHM and highest HAA5 LRAAs | |
50,000 to 249,999 | quarterly | 4 dual sample sets at the locations with the two highest TTHM and two highest HAA5 LRAAs | |
250,000 to 999,999 | quarterly | 6 dual sample sets at the locations with the three highest TTHM and three highest HAA5 LRAAs | |
1,000,000 to 4,999,999 | quarterly | 8 dual sample sets at the locations with the four highest TTHM and four highest HAA5 LRAAs | |
5,000,000 or more | quarterly | 10 dual sample sets at the locations with the five highest TTHM and five highest HAA5 LRAAs | |
Groundwater | less than 500 | every third year (triennial) | 1 TTHM and 1 HAA5 at the respective locations and quarters with the highest individual DBP; 1 dual sample set per year if the highest TTHM and HAA5 measurements occurred at the same location and quarter. |
500 to 9,999 | Annual | 1 TTHM and 1 HAA5 at the respective locations and quarters with the highest individual DBP; 1 dual sample set per year if the highest TTHM and HAA5 measurements occurred at the same location and quarter. | |
10,000 to 99,999 | Annual | 2 dual sample sets: one at the location and during the quarter with the highest TTHM single measurement, one at the location and during the quarter with the highest HAA5 single measurement | |
100,000 to 499,999 | quarterly | 2 dual sample sets at the locations with the highest TTHM and highest HAA5 LRAAs | |
500,000 or more | quarterly | 4 dual sample sets at the locations with the two highest TTHM and two highest HAA5 LRAAs |
Wis. Admin. Code Department of Natural Resources § NR 809.63