Non-Transient Non-Community · PWSID MT0003089

Rau School District No 21

Serves 80 peopleGroundwaterOwner: Local GovernmentSidney, MontanaServes a school or daycare
1 open treatment violation.

Open for: Lead and Copper Rule. EPA counts treatment-technique violations as health-based: a required protective step was not done. It is not a measurement of contamination.

On record since 1994: 95 violations. 3 treatment lapses · 88 missed or late tests · 4 notices or reports. Most recent began 2025-04-01.

None of them is a measurement of contaminated water.

For this year's test results, ask the utility for its annual Consumer Confidence Report. Every community system must publish one.

0Over the limit
3Treatment lapse1 open
88Missed or late test10 open
4Notice or report

More violations on record than 98% of active water systems in Montana. Small systems with no staff chemist often rack up missed-test violations; big utilities rarely do.

The record, year by year

1994 · Treatment lapse: 119951997 · Missed or late test: 12000 · Missed or late test: 120002001 · Missed or late test: 22002 · Treatment lapse: 12002 · Missed or late test: 12003 · Missed or late test: 22004 · Missed or late test: 22005 · Missed or late test: 120052006 · Missed or late test: 12007 · Missed or late test: 12010 · Missed or late test: 1201020152016 · Missed or late test: 32016 · Notice or report: 12017 · Treatment lapse: 12017 · Missed or late test: 242017 · Missed or late test: 242017 · Missed or late test: 242017 · Missed or late test: 242017 · Missed or late test: 242017 · Missed or late test: 242017 · Missed or late test: 242017 · Missed or late test: 242017 · Notice or report: 12018 · Notice or report: 12019 · Missed or late test: 22020 · Missed or late test: 232020 · Missed or late test: 232020 · Missed or late test: 232020 · Missed or late test: 232020 · Missed or late test: 232020 · Missed or late test: 232020 · Missed or late test: 232020 · Missed or late test: 2320202021 · Missed or late test: 162021 · Missed or late test: 162021 · Missed or late test: 162021 · Missed or late test: 162021 · Missed or late test: 162021 · Missed or late test: 162021 · Notice or report: 12022 · Missed or late test: 22023 · Missed or late test: 12024 · Missed or late test: 22025 · Missed or late test: 22025
One square ≈ 3 violations (rounded up), by the year they began. Empty columns are years with nothing on EPA's record.
3% treatment lapse · 393% missed or late test · 884% notice or report · 4

Across Montana, 85% of violations are missed or late tests and 3% are water over a limit.

What you can do

  • Lead: Run cold water for 30 seconds to 2 minutes before using it for drinking or cooking, especially after the water has been sitting for several hours. Use only cold water for cooking and baby formula. Consider a water filter certified to remove lead (look for NSF/ANSI Standard 53 certification). Have your water tested if you live in an older home.

Lead & copper at the tap

Utilities sample taps in homes most likely to have lead pipes, and report the 90th-percentile result: 9 in 10 homes sampled came in at or below this number. Above the red line (the action level) the utility must act. The action level is not a safe level; EPA's health goal for lead is zero. EPA's file does not date these results, so they are shown highest first.

Lead, 90th percentile 7 results on file · action level 15 ppb

21 ppb
7 ppb
1 ppb
1 ppb
0 ppb
0 ppb
0 ppb

Copper, 90th percentile 1 result on file · action level 1.3 mg/L

1.7 mg/L

Open now (11)

  1. 2019-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  2. 2007-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  3. 2006-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  4. 2005-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  5. 2004-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  6. 2004-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  7. 2003-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  8. 2002-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  9. 2002-01-01Lead and Copper RuleOCCT/SOWT Study/RecommendationOpen
  10. 2001-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  11. 2000-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen

Every violation on record

  1. 2025-04-01Lead and Copper RuleLead Consumer NoticeBack in compliance
  2. 2025-01-01OrthophosphateWater Quality Parameter M/RPeriod ended · no return to compliance on file
  3. 2024-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  4. 2024-01-01OrthophosphateWater Quality Parameter M/RPeriod ended · no return to compliance on file
  5. 2023-11-29Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  6. 2022-10-01Revised Total Coliform RuleMONBack in compliance
  7. 2022-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  8. 2021-09-02Revised Total Coliform RuleRPTBack in compliance
  9. 2021-09-01Revised Total Coliform RuleMONBack in compliance
  10. 2021-07-01Orthophosphate ×2Water Quality Parameter M/RBack in compliance
  11. 2021-02-01Revised Total Coliform RuleMONBack in compliance
  12. 2021-01-01Total Haloacetic Acids (HAA5)Monitoring and Reporting (DBP)Period ended · no return to compliance on file
  13. 2021-01-01Trihalomethanes (TTHM)Monitoring and Reporting (DBP)Period ended · no return to compliance on file
  14. 2021-01-01Calcium ×2Water Quality Parameter M/RBack in compliance
  15. 2021-01-01Temperature (Centigrade) ×2Water Quality Parameter M/RBack in compliance
  16. 2021-01-01Alkalinity, Total ×2Water Quality Parameter M/RBack in compliance
  17. 2021-01-01pH ×2Water Quality Parameter M/RBack in compliance
  18. 2021-01-01Conductivity @ 25 C Umhos/Cm ×2Water Quality Parameter M/RBack in compliance
  19. 2020-01-01ChlordaneMonitoring, RegularBack in compliance
  20. 2020-01-01PentachlorophenolMonitoring, RegularBack in compliance
  21. 2020-01-01Benzo(a)pyreneMonitoring, RegularBack in compliance
  22. 2020-01-01HexachlorobenzeneMonitoring, RegularBack in compliance
  23. 2020-01-012, 4, 5-TpMonitoring, RegularBack in compliance
  24. 2020-01-012, 4-DMonitoring, RegularBack in compliance
  25. 2020-01-01Heptachlor epoxideMonitoring, RegularBack in compliance
Show the other 64 entries
  1. 2020-01-01HeptachlorMonitoring, RegularBack in compliance
  2. 2020-01-01LassoMonitoring, RegularBack in compliance
  3. 2020-01-01AtrazineMonitoring, RegularBack in compliance
  4. 2020-01-01CarbofuranMonitoring, RegularBack in compliance
  5. 2020-01-01HexachlorocyclopentadieneMonitoring, RegularBack in compliance
  6. 2020-01-01DinosebMonitoring, RegularBack in compliance
  7. 2020-01-01PicloramMonitoring, RegularBack in compliance
  8. 2020-01-01Di(2-ethylhexyl) phthalateMonitoring, RegularBack in compliance
  9. 2020-01-01SimazineMonitoring, RegularBack in compliance
  10. 2020-01-01OxamylMonitoring, RegularBack in compliance
  11. 2020-01-01Di(2-ethylhexyl) adipateMonitoring, RegularBack in compliance
  12. 2020-01-01DalaponMonitoring, RegularBack in compliance
  13. 2020-01-01ToxapheneMonitoring, RegularBack in compliance
  14. 2020-01-01MethoxychlorMonitoring, RegularBack in compliance
  15. 2020-01-01Bhc-GammaMonitoring, RegularBack in compliance
  16. 2020-01-01EndrinMonitoring, RegularBack in compliance
  17. 2019-09-06E. ColiMonitoring, Source Water (GWR)Back in compliance
  18. 2019-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  19. 2018-09-02Revised Total Coliform RuleRPTBack in compliance
  20. 2017-09-02Revised Total Coliform RuleRPTBack in compliance
  21. 2017-08-01Revised Total Coliform RuleMONBack in compliance
  22. 2017-04-10Lead and Copper RuleOCCT/SOWT Study/RecommendationBack in compliance
  23. 2017-02-01Revised Total Coliform RuleMONBack in compliance
  24. 2017-01-01StyreneMonitoring, RegularBack in compliance
  25. 2017-01-01EthylbenzeneMonitoring, RegularBack in compliance
  26. 2017-01-01TolueneMonitoring, RegularBack in compliance
  27. 2017-01-01BenzeneMonitoring, RegularBack in compliance
  28. 2017-01-01ChlorobenzeneMonitoring, RegularBack in compliance
  29. 2017-01-01TetrachloroethyleneMonitoring, RegularBack in compliance
  30. 2017-01-011,1,2-TrichloroethaneMonitoring, RegularBack in compliance
  31. 2017-01-01TrichloroethyleneMonitoring, RegularBack in compliance
  32. 2017-01-011,2-DichloropropaneMonitoring, RegularBack in compliance
  33. 2017-01-01Carbon tetrachlorideMonitoring, RegularBack in compliance
  34. 2017-01-011,1,1-TrichloroethaneMonitoring, RegularBack in compliance
  35. 2017-01-011,2-DichloroethaneMonitoring, RegularBack in compliance
  36. 2017-01-01trans-1,2-DichloroethyleneMonitoring, RegularBack in compliance
  37. 2017-01-011,1-DichloroethyleneMonitoring, RegularBack in compliance
  38. 2017-01-01Vinyl chlorideMonitoring, RegularBack in compliance
  39. 2017-01-01p-DichlorobenzeneMonitoring, RegularBack in compliance
  40. 2017-01-01o-DichlorobenzeneMonitoring, RegularBack in compliance
  41. 2017-01-01DichloromethaneMonitoring, RegularBack in compliance
  42. 2017-01-01Xylenes, TotalMonitoring, RegularBack in compliance
  43. 2017-01-01cis-1,2-DichloroethyleneMonitoring, RegularBack in compliance
  44. 2017-01-011,2,4-TrichlorobenzeneMonitoring, RegularBack in compliance
  45. 2017-01-01Nitrate-NitriteMonitoring, RegularBack in compliance
  46. 2016-12-01Revised Total Coliform RuleMONBack in compliance
  47. 2016-11-01Revised Total Coliform RuleMONBack in compliance
  48. 2016-10-01ChlorineMonitoring and Reporting (DBP)Back in compliance
  49. 2016-04-02Revised Total Coliform RuleOtherBack in compliance
  50. 2010-09-30Lead and Copper RuleLead Consumer NoticeBack in compliance
  51. 2007-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  52. 2006-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  53. 2005-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  54. 2004-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  55. 2004-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  56. 2003-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  57. 2003-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  58. 2002-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  59. 2002-01-01Lead and Copper RuleOCCT/SOWT Study/RecommendationOpen
  60. 2001-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  61. 2001-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  62. 2000-07-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/ROpen
  63. 1997-01-01Lead and Copper RuleFollow-up Or Routine LCR Tap M/RBack in compliance
  64. 1994-03-01Lead and Copper RulePublic EducationBack in compliance

System details

Population served80
Service connections1
Water sourceGroundwater
System typeNon-Transient Non-Community
OwnerLocal Government
StatusActive
CitySidney
EPA ZIP on file59270

Areas served

  • Sidney, Richland County

Reading this record

Rau School District No 21 is a non-transient non-community that draws from groundwater and serves about 80 people in Sidney, Montana. Everything above comes from the EPA's Safe Drinking Water Information System (SDWIS), where states report every violation by every public water system.

Four kinds of violation. Only one is a measurement of the water: over the limit means a test came back above a legal maximum (an MCL). A treatment lapse means a required protective step was not done, such as disinfection, filtration, fixing a defect an inspector found, or filing a lead-pipe inventory. A missed or late test means a required test was skipped or never reported. That is the most common kind, and the most misread: it does not mean the water was bad, and it does not mean the water was fine. Notices and reports covers public notices and the annual Consumer Confidence Report.

Status. “Back in compliance” means the state recorded a return to compliance. “Period ended” means the violation's compliance period is over but no return to compliance was ever filed, which is common in older records. EPA's federal copy lags state records by months, so call the utility for anything current.