Table 2
Total Coliform Monitoring Frequency
Population served | Minimum number of samples per month |
1 to 1,000* | 1 |
1,001 to 2,500 | 2 |
2,501 to 3,300 | 3 |
3,301 to 4,100 | 4 |
4,101 to 4,900 | 5 |
4,901 to 5,800 | 6 |
5,801 to 6,700 | 7 |
6,701 to 7,600 | 8 |
7,601 to 8,500 | 9 |
8,501 to 12,900 | 10 |
12,901 to 17,200 | 15 |
17,201 to 21,500 | 20 |
21,501 to 25,000 | 25 |
25,001 to 33,000 | 30 |
33,001 to 41,000 | 40 |
41,001 to 50,000 | 50 |
50,001 to 59,000 | 60 |
59,001 to 70,000 | 70 |
70,001 to 83,000 | 80 |
83,001 to 96,000 | 90 |
96,001 to 130,000 | 100 |
130,001 to 220,000 | 120 |
220,001 to 320,000 | 150 |
320,001 to 450,000 | 180 |
450,001 to 600,000 | 210 |
600,001 to 780,000 | 240 |
780,001 to 970,000 | 270 |
970,001 to 1,230,000 | 300 |
1,230,001 to 1,520,000 | 330 |
1,520,001 to 1,850,000 | 360 |
1,850,001 to 2,270,000 | 390 |
2,270,001 to 3,020,000 | 420 |
3,020,001 to 3,960,000 | 450 |
3,960,001 or more | 480 |
*Noncommunity systems using only protected groundwater sources and serving less than twenty-five individuals, may collect and submit for analysis, one sample every three months per WAC 246-290-300(3)(e)(ii).
40 C.F.R. 141.600 | General requirements. |
40 C.F.R. 141.601 | Standard monitoring. |
40 C.F.R. 141.602 | System specific studies. |
40 C.F.R. 141.603 | 40/30 certification. |
40 C.F.R. 141.604 | Very small system waivers. |
40 C.F.R. 141.605 | Subpart V compliance monitoring location recommendations. |
TABLE 3
SAL MONITORING
Contaminant or Group of Contaminants | Applicable Water System Classification | Initial Sampling | Routine Sampling Frequency | Sampling Location |
Organic Contaminants | ||||
Per- and polyfluoroalkyl substances (PFAS) | Community and NTNC, and if applicable, TNC | One sample on or before December 31, 2025 | Once every three years | Per the locations described in WAC 246-290-300(7)(b) and Table 4 of this section |
TABLE 4
MONITORING LOCATION
Sample Type | Sample Location |
Asbestos | One sample from distribution system or if required by department, from the source. |
Bacteriological | From representative points throughout distribution system. |
Cryptosporidium and E. coli (Source Water) - WAC 246-290-630(16) | Under 40 C.F.R. 141.703. |
Complete Inorganic Chemical & Physical | From a point representative of the source, after treatment, and prior to entry to the distribution system. |
Lead/Copper | From the distribution system at targeted sample tap locations. |
Nitrate/Nitrite | From a point representative of the source, after treatment, and prior to entry to the distribution system. |
Disinfection Byproducts - TTHMs and HAA5 - WAC 246-290-300(6) | Under 40 C.F.R. 141.132(b)(1) (Subpart L of the C.F.R.). |
Disinfection Byproducts - TTHMs and HAA5 - WAC 246-290-300(6) | Under 40 C.F.R. 141.600 - 629 (IDSE and LRAA in Subparts U and V of the C.F.R.). |
Disinfection Byproducts - Chlorite (Systems adding chlorine dioxide) | Under 40 C.F.R. 141.132(b)(2). |
Disinfection Byproducts - Bromate (Systems adding ozone) | Under 40 C.F.R. 141.132(b)(3). |
Disinfectant Residuals - Chlorine and Chloramines | Under 40 C.F.R. 141.132(c)(1). |
Disinfectant Residuals - Chlorine dioxide | Under 40 C.F.R. 141.132(c)(2). |
Disinfection Precursors - Total Organic Carbon (TOC) | Under 40 C.F.R. 141.132(d). |
Disinfection Precursors - Bromide (Systems using ozone) | From the source before treatment. |
Radionuclides | From a point representative of the source, after treatment and prior to entry to distribution system. |
Organic Chemicals (VOCs, SOCs, & PFAS) | From a point representative of the source, after treatment and prior to entry to distribution system. |
Other contaminants without As directed by the department. an MCL, MRDL, TT or SAL
Wash. Admin. Code § 246-290-300
Statutory Authority: RCW 43.20.050(2) and 70.119A.080. 11-17-062, § 246-290-300, filed 8/15/11, effective 10/1/11. Statutory Authority: RCW 43.20.050 and 70.119A.080. 10-20-068, § 246-290-300, filed 9/29/10, effective 11/1/10. Statutory Authority: RCW 43.20.050. 09-21-045, § 246-290-300, filed 10/13/09, effective 1/4/10. Statutory Authority: RCW 70.119A.180 and 43.20.050. 08-03-061, § 246-290-300, filed 1/14/08, effective 2/14/08. Statutory Authority: RCW 43.20.050 and 70.119A.080. 04-04-056, § 246-290-300, filed 1/30/04, effective 3/1/04. Statutory Authority: RCW 43.20.050(2) and (3) and 70.119A.080. 03-08-037, § 246-290-300, filed 3/27/03, effective 4/27/03. Statutory Authority: RCW 43.02.050 [43.20.050]. 99-07-021, § 246-290-300, filed 3/9/99, effective 4/9/99. Statutory Authority: RCW 43.20.050. 94-14-001, § 246-290-300, filed 6/22/94, effective 7/23/94; 93-08-011 (Order 352B), § 246-290-300, filed 3/25/93, effective 4/25/93; 92-04-070 (Order 241B), § 246-290-300, filed 2/4/92, effective 3/6/92. Statutory Authority: Chapter 43.20 RCW. 91-07-031 (Order 150B), § 246-290-300, filed 3/15/91, effective 4/15/91. Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-290-300, filed 12/27/90, effective 1/31/91. Statutory Authority: P.L. 99-339. 89-21-020 (Order 336), § 248-54-165, filed 10/10/89, effective 11/10/89. Statutory Authority: RCW 34.04.045. 88-05-057 (Order 307), § 248-54-165, filed 2/17/88. Statutory Authority: RCW 43.20.050. 83-19-002 (Order 266), § 248-54-165, filed 9/8/83.