| Chemical Sampling Schedule Status | |||||||||||
| Facility ID |
Analyte or Group | Sampling Interval |
Monitoring Period | Days Until End |
Samples Required |
Samples Received |
Last Sample Date |
||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Start | End | ||||||||||
| CH-A COMMON HEADER FOR WTP-A | TOC & ALKALINITY | notes | Quarterly | 01/01/2026 - 03/31/2026 | 9 | 1 | done | 03/04/2026 | |||
| DIST-A DISTRIBUTION SYSTEM | STAGE 2 DBP | notes | Yearly | 01/01/2026 - 12/31/2026 | 284 | 1 | incomplete | 07/09/2025 | |||
| Seasonal sampling period: 07/01 thru 07/31 | |||||||||||
| EP-A EP FOR TUALATIN RIVER | HEXACHLOROCYCLOPENTADIENE | Quarterly | 01/01/2026 - 03/31/2026 | 9 | 1 | done | 01/07/2026 | ||||
| EP-A EP FOR TUALATIN RIVER | ARSENIC | notes | 9 Years | 01/01/2020 - 12/31/2028 | 1,015 | 1 | done | 11/05/2025 | |||
| EP-A EP FOR TUALATIN RIVER | IOC | notes | 9 Years | 01/01/2020 - 12/31/2028 | 1,015 | 1 | done | 11/05/2025 | |||
| EP-A EP FOR TUALATIN RIVER | NITRATE | Yearly | 01/01/2026 - 12/31/2026 | 284 | 1 | incomplete | 04/02/2025 | ||||
| EP-A EP FOR TUALATIN RIVER | NITRITE | notes | 9 Years | 01/01/2020 - 12/31/2028 | 1,015 | 1 | done | 04/02/2025 | |||
| EP-A EP FOR TUALATIN RIVER | RAD - GROSS ALPHA | notes | 9 Years | 01/01/2026 - 12/31/2034 | 3,206 | 1 | incomplete | 04/07/2021 | |||
| EP-A EP FOR TUALATIN RIVER | RAD - RADIUM 226/228 | 9 Years | 01/01/2023 - 12/31/2031 | 2,110 | 1 | incomplete | 04/07/2021 | ||||
| EP-A EP FOR TUALATIN RIVER | RAD - URANIUM | notes | 9 Years | 01/01/2026 - 12/31/2034 | 3,206 | 1 | incomplete | 04/07/2021 | |||
| EP-A EP FOR TUALATIN RIVER | SOC | notes | 3 Years | 01/01/2026 - 12/31/2028 | 1,015 | 2 | incomplete | 11/05/2025 | |||
| EP-A EP FOR TUALATIN RIVER | VOLATILE ORGANICS | Yearly | 01/01/2026 - 12/31/2026 | 284 | 1 | incomplete | 11/05/2025 | ||||
| SRC-AA TUALATIN RIVER | CYANOTOXINS | 2 Weeks | -- | -- | -- | -- | -- | 10/20/2025 | |||
| Seasonal sampling period: 05/01 thru 10/31 | |||||||||||
| WTP-A TP FOR TUALATIN RIVER | TOTAL ORGANIC CARBON | notes | Monthly | 03/01/2026 - 03/31/2026 | 9 | 1 | done | 03/04/2026 | |||
6 secs | |||||||||||
| Expired Schedules | |||||||||
| Facility ID |
Analyte or Group | Sampling Interval |
Start | End | Samples Required |
Notes | |||
| CH-A COMMON HEADER FOR WTP-A | TOC & ALKALINITY | Monthly | 01/01/2002 | 12/31/2005 | 1 | Raw and filtered TOC and alkalinity | |||
| DIST-A DISTRIBUTION SYSTEM | HAA5 & TTHM | Quarterly | 01/01/2002 | 06/30/2008 | 4 | Reflects 4 RT Samples Per QT Per WTP | |||
| EP-A EP FOR TUALATIN RIVER | ARSENIC | Yearly | 01/01/2002 | 12/31/2010 | 1 | ||||
| EP-A EP FOR TUALATIN RIVER | HEXACHLOROCYCLOPENTADIENE | Quarterly | 01/01/2019 | 12/31/2019 | 1 | ||||
| EP-A EP FOR TUALATIN RIVER | HEXACHLOROCYCLOPENTADIENE | Quarterly | 01/01/2022 | 12/31/2022 | 1 | ||||
| EP-A EP FOR TUALATIN RIVER | HEXACHLOROCYCLOPENTADIENE | Yearly | 01/01/2020 | 12/31/2021 | 1 | Collect sample between October 1 and December 31. | |||
| EP-A EP FOR TUALATIN RIVER | HEXACHLOROCYCLOPENTADIENE | Yearly | 01/01/2023 | 12/31/2025 | 1 | Sample in 4th quarter Oct - Dec | |||
| EP-A EP FOR TUALATIN RIVER | PFAS | Quarterly | 01/01/2023 | 12/31/2025 | 1 | ||||
| EP-A EP FOR TUALATIN RIVER | RAD - RADIUM 226/228 | 6 Years | 01/01/2008 | 12/31/2013 | 1 | ||||
| WTP-A TP FOR TUALATIN RIVER | TOTAL ORGANIC CARBON | Monthly | 01/01/2002 | 12/31/2005 | 1 | Post Filtration TOC | |||
| WTP-A TP FOR TUALATIN RIVER | TOTAL ORGANIC CARBON | Quarterly | 01/01/2006 | 12/31/2019 | 1 | Post Filtration TOC | |||