Hesperia Wd

PFAS monitoring results for a public water system in California

CA3610024UCMR 5EPA monitoring data
10.2Highest PFOA result, ppt
11.1Highest PFOS result, ppt
1.05Highest Hazard Index
900Results
PWSID
CA3610024
State
California
System type
community water system (CWS)
Population served
101,836
City
Hesperia
Counties
San Bernardino County
Primary source water
groundwater
UCMR 5 sampling
2023-07-12 to 2025-01-15 · 15 entry point(s) · water types: GW
Service-area boundary
authoritative

PFOS 1–3 × its limit highest single result
PFOS 1–3 × its limit worst entry-point average

These are monitoring results collected under EPA's Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) at entry points, where treated water enters the distribution system; they are not tap-water samples. They are not compliance determinations: compliance with EPA's 2024 PFAS limits is judged on running annual averages of compliance monitoring, required from 2029, so a single UCMR 5 result at or above a limit is not a violation. “< MRL” means the compound was not quantified at EPA's minimum reporting level; it does not mean zero.

Water purchased from

Seller results are the seller's own entry-point samples, not measurements of this system's water. This system's own samples (below) may reflect purchased water, its own sources, or both.

Compared with EPA's 2024 values

Highest single resultWorst entry-point average*Limit
PFOA (ppt)10.25.14
PFOS (ppt)11.15.554
Hazard Index1.050.5251.0†

“<MRL” = every result for the compound was below its reporting limit. * Mean of all samples at each entry point with non-detects = 0 (EPA compliance convention; the Hazard Index also uses non-detects = 0); a screening comparison, not a formal running annual average. † Rescission proposed May 2026. PFOA/PFOS MCL 4 ppt (2024 NPDWR, in effect). PFHxS, PFNA, HFPO-DA (10 ppt each) and the Hazard Index (1.0) are 2024 NPDWR values; EPA proposed rescinding them on 18 May 2026 (comment period closed 20 Jul 2026).

Compared with California guidance levels

Highest single resultWorst entry-point average*California
PFHxS (ppt)10.55.253 (guidance)
PFOA (ppt)10.25.14 (guidance)
PFOS (ppt)11.15.554 (guidance)
PFBS (ppt)00500 (guidance)
PFHxA (ppt)5.42.71,000 (guidance)

Sum standards add the listed compounds within each sample (non-detects = 0). State compliance is normally judged on averages over time; these are screening comparisons.

Sampling history

Sampled 2023-07-12 to 2025-01-15 · 15 entry point(s) · water types: GW · 40 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2023-07-12Well 18 (GW)SE1n/an/an/anone
2023-07-12Well 24 (GW)SE1n/an/an/anone
2023-07-12Well 25 (GW)SE1n/an/an/anone
2023-07-12Well 32 (GW)SE1n/an/an/anone
2023-07-12Well 4a (GW)SE1n/an/an/anone
2023-07-19Well 14b (GW)SE1<4<40none
2023-07-19Well 15a (GW)SE1<4<40none
2023-07-19Well 17 (GW)SE1<4<40none
2023-07-19Well 19a (GW)SE1<4<40none
2023-07-19Well 3a (GW)SE1<4<406:2 FTS 50.3
2023-07-26Well 14a (GW)SE1<4<40none
2023-07-26Well 20 (GW)SE1<4<40none
2023-07-26Well 29 (GW)SE1<4<40none
2023-07-26Well 5a (GW)SE1<4<40none
2023-08-09Well 18 (GW)SE1n/an/an/anone
2023-08-09Well 24 (GW)SE1n/an/an/anone
2023-08-09Well 25 (GW)SE1n/an/an/anone
2023-08-09Well 32 (GW)SE1n/an/an/anone
2023-08-09Well 4a (GW)SE1n/an/an/anone
2023-08-30Well 18 (GW)SE110.211.11.05PFHpA 3.1, PFHxA 5.4, PFPeA 4.2
2023-08-30Well 25 (GW)SE1<4<40none
2023-08-30Well 4a (GW)SE1<4<40none
2023-10-17Well 32 (GW)SE1<4<40none
2023-11-02Well 24 (GW)SE1<4<40none
2024-01-24Well 18 (GW)SE2<4<40none
2024-01-24Well 19a (GW)SE2<4<40none
2024-01-24Well 24 (GW)SE2<4<40none
2024-01-24Well 25 (GW)SE2<4<40none
2024-01-24Well 29 (GW)SE2<4<40none
2024-01-24Well 4a (GW)SE2<4<40none
2024-01-24Well 5a (GW)SE2<44.20.35none
2024-01-31Well 14a (GW)SE2<4<40none
2024-01-31Well 14b (GW)SE2<4<40none
2024-01-31Well 15a (GW)SE2<4<40none
2024-01-31Well 17 (GW)SE2<4<40none
2024-01-31Well 20 (GW)SE2<4<40none
2024-01-31Well 3a (GW)SE2<4<40none
2024-07-30Well 22a (GW)SE1<4<40none
2024-08-13Well 32 (GW)SE27.49.90.84PFHxA 3.7, lithium 10.2 µg/L
2025-01-15Well 22a (GW)SE2<4<40none

“<4” = not detected at the reporting limit shown; “n/a” = not analyzed in that sample. Highlighted = at or above the 4 ppt MCL. HI computed per sample with non-detects as 0. Other detections lists every other quantified compound (lithium in µg/L).

All results by entry point

900 results. Each column is one sampling visit (date and UCMR 5 sample event). A number is a measured concentration; “< 4” = below the minimum reporting level shown; “–” = not analyzed in that visit. PFAS in ppt (ng/L); lithium in µg/L.

Well 14a facility 90003 · sample point EP001 · groundwater

CompoundMRL2023-07-26
SE1
2024-01-31
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 14b facility 90004 · sample point EP001 · groundwater

CompoundMRL2023-07-19
SE1
2024-01-31
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 15a facility 90005 · sample point EP001 · groundwater

CompoundMRL2023-07-19
SE1
2024-01-31
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 17 facility 90006 · sample point EP001 · groundwater

CompoundMRL2023-07-19
SE1
2024-01-31
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 18 facility 90007 · sample point EP001 · groundwater

CompoundMRL2023-07-12
SE1
2023-08-09
SE1
2023-08-30
SE1
2024-01-24
SE2
PFHpA3 ppt––3.1< 3
PFHxA3 ppt––5.4< 3
PFHxS3 ppt––10.5< 3
PFOA4 ppt––10.2< 4
PFOS4 ppt––11.1< 4
PFPeA3 ppt––4.2< 3
11Cl-PF3OUdS5 ppt––< 5< 5
4:2 FTS3 ppt––< 3< 3
6:2 FTS5 ppt––< 5< 5
8:2 FTS5 ppt––< 5< 5
9Cl-PF3ONS2 ppt––< 2< 2
ADONA3 ppt––< 3< 3
HFPO-DA5 ppt––< 5< 5
NEtFOSAA5 ppt–< 5–< 5
NFDHA20 ppt––< 20< 20
NMeFOSAA6 ppt–< 6–< 6
PFBA5 ppt––< 5< 5
PFBS3 ppt––< 3< 3
PFDA3 ppt––< 3< 3
PFDoA3 ppt––< 3< 3
PFEESA3 ppt––< 3< 3
PFHpS3 ppt––< 3< 3
PFMBA3 ppt––< 3< 3
PFMPA4 ppt––< 4< 4
PFNA4 ppt––< 4< 4
PFPeS4 ppt––< 4< 4
PFTA8 ppt–< 8–< 8
PFTrDA7 ppt–< 7–< 7
PFUnA2 ppt––< 2< 2
lithium9 µg/L< 9––< 9

Well 19a facility 90008 · sample point EP001 · groundwater

CompoundMRL2023-07-19
SE1
2024-01-24
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 20 facility 90009 · sample point EP001 · groundwater

CompoundMRL2023-07-26
SE1
2024-01-31
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 22a facility 90014 · sample point EP001 · groundwater

CompoundMRL2024-07-30
SE1
2025-01-15
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 24 facility 90011 · sample point EP001 · groundwater

CompoundMRL2023-07-12
SE1
2023-08-09
SE1
2023-11-02
SE1
2024-01-24
SE2
11Cl-PF3OUdS5 ppt––< 5< 5
4:2 FTS3 ppt––< 3< 3
6:2 FTS5 ppt––< 5< 5
8:2 FTS5 ppt––< 5< 5
9Cl-PF3ONS2 ppt––< 2< 2
ADONA3 ppt––< 3< 3
HFPO-DA5 ppt––< 5< 5
NEtFOSAA5 ppt–< 5–< 5
NFDHA20 ppt––< 20< 20
NMeFOSAA6 ppt–< 6–< 6
PFBA5 ppt––< 5< 5
PFBS3 ppt––< 3< 3
PFDA3 ppt––< 3< 3
PFDoA3 ppt––< 3< 3
PFEESA3 ppt––< 3< 3
PFHpA3 ppt––< 3< 3
PFHpS3 ppt––< 3< 3
PFHxA3 ppt––< 3< 3
PFHxS3 ppt––< 3< 3
PFMBA3 ppt––< 3< 3
PFMPA4 ppt––< 4< 4
PFNA4 ppt––< 4< 4
PFOA4 ppt––< 4< 4
PFOS4 ppt––< 4< 4
PFPeA3 ppt––< 3< 3
PFPeS4 ppt––< 4< 4
PFTA8 ppt–< 8–< 8
PFTrDA7 ppt–< 7–< 7
PFUnA2 ppt––< 2< 2
lithium9 µg/L< 9––< 9

Well 25 facility 90013 · sample point EP001 · groundwater

CompoundMRL2023-07-12
SE1
2023-08-09
SE1
2023-08-30
SE1
2024-01-24
SE2
11Cl-PF3OUdS5 ppt––< 5< 5
4:2 FTS3 ppt––< 3< 3
6:2 FTS5 ppt––< 5< 5
8:2 FTS5 ppt––< 5< 5
9Cl-PF3ONS2 ppt––< 2< 2
ADONA3 ppt––< 3< 3
HFPO-DA5 ppt––< 5< 5
NEtFOSAA5 ppt–< 5–< 5
NFDHA20 ppt––< 20< 20
NMeFOSAA6 ppt–< 6–< 6
PFBA5 ppt––< 5< 5
PFBS3 ppt––< 3< 3
PFDA3 ppt––< 3< 3
PFDoA3 ppt––< 3< 3
PFEESA3 ppt––< 3< 3
PFHpA3 ppt––< 3< 3
PFHpS3 ppt––< 3< 3
PFHxA3 ppt––< 3< 3
PFHxS3 ppt––< 3< 3
PFMBA3 ppt––< 3< 3
PFMPA4 ppt––< 4< 4
PFNA4 ppt––< 4< 4
PFOA4 ppt––< 4< 4
PFOS4 ppt––< 4< 4
PFPeA3 ppt––< 3< 3
PFPeS4 ppt––< 4< 4
PFTA8 ppt–< 8–< 8
PFTrDA7 ppt–< 7–< 7
PFUnA2 ppt––< 2< 2
lithium9 µg/L< 9––< 9

Well 29 facility 90015 · sample point EP001 · groundwater

CompoundMRL2023-07-26
SE1
2024-01-24
SE2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 32 facility 90016 · sample point EP001 · groundwater

CompoundMRL2023-07-12
SE1
2023-08-09
SE1
2023-10-17
SE1
2024-08-13
SE2
PFHxA3 ppt––< 33.7
PFHxS3 ppt––< 38.4
PFOA4 ppt––< 47.4
PFOS4 ppt––< 49.9
11Cl-PF3OUdS5 ppt––< 5< 5
4:2 FTS3 ppt––< 3< 3
6:2 FTS5 ppt––< 5< 5
8:2 FTS5 ppt––< 5< 5
9Cl-PF3ONS2 ppt––< 2< 2
ADONA3 ppt––< 3< 3
HFPO-DA5 ppt––< 5< 5
NEtFOSAA5 ppt–< 5–< 5
NFDHA20 ppt––< 20< 20
NMeFOSAA6 ppt–< 6–< 6
PFBA5 ppt––< 5< 5
PFBS3 ppt––< 3< 3
PFDA3 ppt––< 3< 3
PFDoA3 ppt––< 3< 3
PFEESA3 ppt––< 3< 3
PFHpA3 ppt––< 3< 3
PFHpS3 ppt––< 3< 3
PFMBA3 ppt––< 3< 3
PFMPA4 ppt––< 4< 4
PFNA4 ppt––< 4< 4
PFPeA3 ppt––< 3< 3
PFPeS4 ppt––< 4< 4
PFTA8 ppt–< 8–< 8
PFTrDA7 ppt–< 7–< 7
PFUnA2 ppt––< 2< 2
lithium9 µg/L< 9––10.2

Well 3a facility 90001 · sample point EP001 · groundwater

CompoundMRL2023-07-19
SE1
2024-01-31
SE2
6:2 FTS5 ppt50.3< 5
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFHxS3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFOS4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Well 4a facility 90017 · sample point EP001 · groundwater

CompoundMRL2023-07-12
SE1
2023-08-09
SE1
2023-08-30
SE1
2024-01-24
SE2
11Cl-PF3OUdS5 ppt––< 5< 5
4:2 FTS3 ppt––< 3< 3
6:2 FTS5 ppt––< 5< 5
8:2 FTS5 ppt––< 5< 5
9Cl-PF3ONS2 ppt––< 2< 2
ADONA3 ppt––< 3< 3
HFPO-DA5 ppt––< 5< 5
NEtFOSAA5 ppt–< 5–< 5
NFDHA20 ppt––< 20< 20
NMeFOSAA6 ppt–< 6–< 6
PFBA5 ppt––< 5< 5
PFBS3 ppt––< 3< 3
PFDA3 ppt––< 3< 3
PFDoA3 ppt––< 3< 3
PFEESA3 ppt––< 3< 3
PFHpA3 ppt––< 3< 3
PFHpS3 ppt––< 3< 3
PFHxA3 ppt––< 3< 3
PFHxS3 ppt––< 3< 3
PFMBA3 ppt––< 3< 3
PFMPA4 ppt––< 4< 4
PFNA4 ppt––< 4< 4
PFOA4 ppt––< 4< 4
PFOS4 ppt––< 4< 4
PFPeA3 ppt––< 3< 3
PFPeS4 ppt––< 4< 4
PFTA8 ppt–< 8–< 8
PFTrDA7 ppt–< 7–< 7
PFUnA2 ppt––< 2< 2
lithium9 µg/L< 9––< 9

Well 5a facility 90002 · sample point EP001 · groundwater

CompoundMRL2023-07-26
SE1
2024-01-24
SE2
PFHxS3 ppt< 33.5
PFOS4 ppt< 44.2
11Cl-PF3OUdS5 ppt< 5< 5
4:2 FTS3 ppt< 3< 3
6:2 FTS5 ppt< 5< 5
8:2 FTS5 ppt< 5< 5
9Cl-PF3ONS2 ppt< 2< 2
ADONA3 ppt< 3< 3
HFPO-DA5 ppt< 5< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt< 20< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt< 5< 5
PFBS3 ppt< 3< 3
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 ppt< 3< 3
PFHpA3 ppt< 3< 3
PFHpS3 ppt< 3< 3
PFHxA3 ppt< 3< 3
PFMBA3 ppt< 3< 3
PFMPA4 ppt< 4< 4
PFNA4 ppt< 4< 4
PFOA4 ppt< 4< 4
PFPeA3 ppt< 3< 3
PFPeS4 ppt< 4< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt< 2< 2
lithium9 µg/L< 9< 9

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFHxS3010%10.5
2023-08-30
0.75–3.45<MRL<MRL<MRL8.4
PFOS3010%11.1
2023-08-30
0.84–4.44<MRL<MRL<MRL9.9
PFHxA307%5.4
2023-08-30
0.3–3.1<MRL<MRL<MRL3.7
PFOA307%10.2
2023-08-30
0.59–4.32<MRL<MRL<MRL7.4
6:2 FTS303%50.3
2023-07-19
1.68–6.51<MRL<MRL<MRL<MRL
PFHpA303%3.1
2023-08-30
0.1–3<MRL<MRL<MRL<MRL
PFPeA303%4.2
2023-08-30
0.14–3.04<MRL<MRL<MRL<MRL
lithium303%10.2
2024-08-13
0.34–9.04<MRL<MRL<MRL<MRL

Never detected (22): 11Cl-PF3OUdS, 4:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFBA, PFBS, PFDA, PFDoA, PFEESA, PFHpS, PFMBA, PFMPA, PFNA, PFPeS, PFTA, PFTrDA, PFUnA.

Left-censored Kaplan–Meier statistics (Helsel 2005; Helsel & Lee 2006, NADA for R). Units: ppt; lithium µg/L. Each compound has one reporting limit, so the Kaplan–Meier mean equals the upper mean bound (non-detects at the MRL); the lower bound sets non-detects to 0. “<MRL” = the percentile falls below the reporting limit and cannot be estimated. These describe this system's UCMR 5 samples, not population estimates.

Sources

  • EPA UCMR 5 occurrence data text files (UCMR5_All.txt; samples 2023-01-09 to 2026-06-17; data summary dated Jul 2026)
  • EPA SDWIS via ECHO SDWA downloads, quarter 2026Q3
  • EPA Public Water System Service Areas v3 (Mar 2026)
  • US Census Bureau cartographic boundary counties 1:500k, 2024
  • EPA/USGS NHDPlus V2 (medium resolution) flowlines, Strahler order 2+

Data build 90f0922cd84f · 2026-10-18T04:12Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.