Forensic evidence record · ev-ca4910013-f-valley-moon-district-pfos
Perfluorooctanesulfonic acid (PFOS)
A single published measurement record with its qualifier, sampling context, source identifier, method note, and stated limitations kept together.
Published evidence record
5.4 ng/LReported measurementSource observations (14)
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-11 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-11 · Method EPA 533
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-09 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-09 · Method EPA 533
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-01 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-01 · Method EPA 533
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-07 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-07 · Method EPA 533
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-13 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-13RE1 · Method EPA 533
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-05 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-05 · Method EPA 533
- PFOS — Sample date: 2024-10-08
Below reporting limit. < Result value not available µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 4J11071-03 · Method EPA 533
- PFOS — Sample date: 2025-04-08
Detected above reporting limit. = 0.0054 µg/L
Reporting limit: 0.004 µg/L. Detection limit: Not available. Benchmark unavailable
Source: src-ucmr5-2024 · UCMR5_All.txt · Sample 5D11052-03 · Method EPA 533
Measurement evidence
- Analyte
- Perfluorooctanesulfonic acid (PFOS)
- Result qualifier
- =
- Reference basis
- 4.0 ng/L federal MCL (2024)
- Sampling location
- Entry Point to Distribution
- Water system ID
- CA4910013
- Source ID
- src-ucmr5-2024
Laboratory context
No laboratory method note was published with this record.
Sampling context
This result represents a entry point to distribution sample. It does not establish the condition at every distribution point or household tap.
Record limitation
System-level entry-point monitoring; not a measurement of the water at an individual household tap.
Source provenance
UCMR5 Analytical Results
Fifth Unregulated Contaminant Monitoring Rule (UCMR5) — PFAS occurrence data
U.S. Environmental Protection Agency · Published 2024
Nationwide entry-point monitoring for 29 PFAS and lithium under the fifth UCMR cycle. Results are entry-point-to-distribution samples, not household-tap measurements.
How to interpret this record
This page preserves one measurement. Interpretation requires its qualifier, reporting limit, reference basis, date, sampling location, and limitations; the number alone is not a safety verdict.
Review finding states →