Forensic evidence record · ev-ca1610003-f-hanford-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
Non-Detect (ND)Reported measurementSource observations (26)
- PFOS — Sample date: 2025-05-21
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 AIE2710-01 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-01 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-03 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-03 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-05 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-05 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-07 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-07 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-09 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-09 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-11 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-11 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-13 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-13 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-15 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-15 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-17 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-17 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-19 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-19 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-21 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-21 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-23 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-23 · Method EPA 533
- PFOS — Sample date: 2025-05-21
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 AIE2710-25 · Method EPA 533
- PFOS — Sample date: 2025-11-19
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 AIK2477-25 · Method EPA 533
Measurement evidence
- Analyte
- Perfluorooctanesulfonic acid (PFOS)
- Result qualifier
- ND
- Reference basis
- 4.0 ng/L federal MCL (2024)
- Sampling location
- Entry Point to Distribution
- Water system ID
- CA1610003
- 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.
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