Transient Non-Community Water System · PWS WA5388382
Shadow Mountain
Sequim, Washington 98382 - drinking water served from groundwater sources to 656 people, tracked in EPA SDWIS and UCMR5.
- 656
- People served
- 38
- EPA violations
- 5
- Health-based
- Untested
- UCMR5 result
The verdict
EPA records 38 drinking-water violations at Shadow Mountain, 13% of them health-based - below the Washington per-system average.
- 38
- Total EPA violations on record
- 13%
- Health-based (MCL / treatment failure)
- 656
- People served by this system
- N/A
- PFAS compounds detected (UCMR5)
Water Quality Snapshot: Shadow Mountain
Shadow Mountain is a private-owned transient non-community water system that delivers drinking water to 656 residents in Sequim, Washington (Clallam County) through 63 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 38 total violations for this system , of which 5 (13%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 32 monitoring and reporting violations are on file. The most recent violation on record dates to 2020.
The most frequently cited contaminant at this system is Nitrate, recorded in 14 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.
Across Washington, EPA tracks 4,557 public water systems serving 9,736,844 people, with 314,648 cumulative violations and 20,590 health-based violations on record. About 92% of systems in the state carry at least one violation, and state-wide the average per system is 69 violations. Statewide, 98 of 247 UCMR5-tested systems have reported PFAS detections (39.7%).
Shadow Mountain's 38 violations sit below the Washington average.
All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.
System Details
- System Type
- Transient Non-Community
- Owner Type
- Private
- Connections
- 63
- County
- Clallam
- School/Daycare
- No
- MCL Violations
- 5
- Monitoring Violations
- 32
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Nitrate | MR | 14 | 2020 |
| Revised Total Coliform Rule | MON | 11 | 2019 |
| Coliform (TCR) | MR | 7 | 2014 |
| Coliform (TCR) | MCL | 5 | 2006 |
Verify This Water System
The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Shadow Mountain.
EPA SDWIS, Federal Reports
EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:
View PWS ID WA5388382 on SDWISSource: EPA SDWIS Federal Reports Search
Washington Drinking Water Authority
Washington State Department of Health, Office of Drinking Water is the primacy agency that licenses and inspects Shadow Mountain under EPA-delegated authority.
Open WA regulator portalSource: Washington State Department of Health, Office of Drinking Water
Violation Timeline
Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.
| Year (latest) | Contaminant | Category | Count | EPA Record |
|---|---|---|---|---|
| 2020 | Nitrate | MR | 14 | SDWIS / WA5388382 / 1040 |
| 2019 | Revised Total Coliform Rule | MON | 11 | SDWIS / WA5388382 / 8000 |
| 2014 | Coliform (TCR) | MR | 7 | SDWIS / WA5388382 / 3100 |
| 2006 | Coliform (TCR) | MCL | 5 | SDWIS / WA5388382 / 3100 |
How Shadow Mountain Compares
Cross-reference this system's record against state averages and the federal MCL framework for context.
| Metric | Shadow Mountain | Washington avg | Federal benchmark |
|---|---|---|---|
| Total violations | 38 | 69 | SDWA compliance, any non-zero count is a recorded breach |
| Health-based violations | 5 | 4.5 | Indicates a contaminant exceeded a federal MCL |
| PFAS detection | None | 39.7% | EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt |
| Population served | 656 | 2,137 | Sizing context for compliance burden |
Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 4,557 regulated public water systems in Washington.
Federal MCL reference, Safe Drinking Water Act thresholds ▼
| Contaminant | Federal MCL / Action Level | Note |
|---|---|---|
| Lead | 0 mg/L (Action Level: 0.015 mg/L) | Lead and Copper Rule treatment technique |
| Arsenic | 0.010 mg/L (10 ppb) | Health-based MCL since 2006 |
| Total Coliform | Treatment technique (RTCR) | Indicator organism, monitoring trigger |
| PFOA / PFOS (PFAS) | 4.0 ppt each (final 2024 rule) | Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026) |
| Nitrate (as N) | 10 mg/L | Acute health risk for infants |
Frequently Asked Questions
Is Shadow Mountain water safe to drink? ▼
How many people does Shadow Mountain serve? ▼
What type of violations does Shadow Mountain have? ▼
Has PFAS been detected in Shadow Mountain water? ▼
What water source does Shadow Mountain use? ▼
Where does this data come from? ▼
Read our methodology - how this data is sourced, computed, and verified.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.