Big Bear Lake Dwp - Big Bear System

PFAS monitoring results for a public water system in California

CA3610044UCMR 5EPA monitoring data
5.5Highest PFOA result, ppt
6.1Highest PFOS result, ppt
0.66Highest Hazard Index
1,200Results
PWSID
CA3610044
State
California
System type
community water system (CWS)
Population served
26,164
City
Big Bear Lake
Counties
San Bernardino County
Primary source water
groundwater
UCMR 5 sampling
2023-11-15 to 2024-04-24 · 22 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.

Compared with EPA's 2024 values

Highest single resultWorst entry-point average*Limit
PFOA (ppt)5.52.754
PFOS (ppt)6.16.14
Hazard Index0.660.6071.0†

“<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)6.66.053 (guidance)
PFOA (ppt)5.52.754 (guidance)
PFOS (ppt)6.16.14 (guidance)
PFBS (ppt)9.68500 (guidance)
PFHxA (ppt)001,000 (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 2023-11-15 to 2024-04-24 · 22 entry point(s) · water types: GW · 42 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2023-11-15Division #2 Well (GW)SE1<4<40.412none
2023-11-15Division #5 Well (GW)SE1<4<40none
2023-11-15Division #6 Well (GW)SE1<4<40lithium 12.3 µg/L
2023-11-15Division #7 Well (GW)SE1<4<40lithium 10.8 µg/L
2023-11-15Division #8 Well (GW)SE1n/an/an/anone
2023-11-16Lake Plant #5 Well (GW)SE1<4<40.363none
2023-11-16Lake Plant #6 Well (GW)SE1<46.10.003none
2023-11-16McAllister Well (GW)SE1<4<40none
2023-11-16Middle School Well (GW)SE1<4<40none
2023-11-16Oak Well (GW)SE1<4<40none
2023-11-29Bow Canyon Well (GW)SE1<4<40none
2023-11-29La Crescenta Well (GW)SE1<4<40none
2023-11-29Sand Canyon Well (GW)SE1<4<40none
2023-11-29Sawmill Well (GW)SE1<4<40none
2023-11-29Sheephorn Well (GW)SE1<4<40none
2023-12-06Dogwood Slant Wells Composite (GW)SE1<4<40none
2023-12-06Lassen #4 Well (GW)SE1<4<40.592none
2023-12-06Lassen Slant Wells Composite (GW)SE1<4<40.5none
2023-12-06Magnolia Well (GW)SE1<4<40none
2023-12-06Maple Well (GW)SE1<4<40none
2023-12-13Lakewood #7 Well (GW)SE1<4<40none
2024-02-27Lassen #4 Well (GW)SE2n/an/an/anone
2024-04-10Goldmine Slant Wells Composite (GW)SE1<4<40.002none
2024-04-17Division #6 Well (GW)SE2<4<40lithium 12.5 µg/L
2024-04-17Division #7 Well (GW)SE2<4<40lithium 14.5 µg/L
2024-04-17Division #8 Well (GW)SE2<4<40.342none
2024-04-17Lake Plant #5 Well (GW)SE2<4<40.435lithium 10.8 µg/L
2024-04-17McAllister Well (GW)SE2<4<40none
2024-04-17Middle School Well (GW)SE2<4<40none
2024-04-17Oak Well (GW)SE2<4<40none
2024-04-18Bow Canyon Well (GW)SE2<4<40.003none
2024-04-18Dogwood Slant Wells Composite (GW)SE2<4<40none
2024-04-18Goldmine Slant Wells Composite (GW)SE25.5<40.003none
2024-04-18La Crescenta Well (GW)SE2<4<40none
2024-04-18Sand Canyon Well (GW)SE2<4<40none
2024-04-18Sheephorn Well (GW)SE2<4<40none
2024-04-24Lakewood #7 Well (GW)SE2<4<40none
2024-04-24Lassen #4 Well (GW)SE2<4<40.622none
2024-04-24Lassen Slant Wells Composite (GW)SE2<4<40.66none
2024-04-24Magnolia Well (GW)SE2<4<40none
2024-04-24Maple Well (GW)SE2<4<40none
2024-04-24Sawmill Well (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

1200 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.

Bow Canyon Well facility 10018 · sample point 18 · groundwater

CompoundMRL2023-11-29
SE1
2024-04-18
SE2
PFBS3 ppt< 36.6
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
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

Division #2 Well facility 10001 · sample point 01 · groundwater

CompoundMRL2023-11-15
SE1
PFBS3 ppt3.9
PFHxS3 ppt4.1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Division #5 Well facility 10002 · sample point 02 · groundwater

CompoundMRL2023-11-15
SE1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NEtFOSAA5 ppt< 5
NFDHA20 ppt< 20
NMeFOSAA6 ppt< 6
PFBA5 ppt< 5
PFBS3 ppt< 3
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFOS4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFTA8 ppt< 8
PFTrDA7 ppt< 7
PFUnA2 ppt< 2
lithium9 µg/L< 9

Division #6 Well facility 10003 · sample point 03 · groundwater

CompoundMRL2023-11-15
SE1
2024-04-17
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/L12.312.5

Division #7 Well facility 10004 · sample point 04 · groundwater

CompoundMRL2023-11-15
SE1
2024-04-17
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/L10.814.5

Division #8 Well facility 10005 · sample point 05 · groundwater

CompoundMRL2023-11-15
SE1
2024-04-17
SE2
PFBS3 ppt–3.9
PFHxS3 ppt–3.4
11Cl-PF3OUdS5 ppt–< 5
4:2 FTS3 ppt–< 3
6:2 FTS5 ppt–< 5
8:2 FTS5 ppt–< 5
9Cl-PF3ONS2 ppt–< 2
ADONA3 ppt–< 3
HFPO-DA5 ppt–< 5
NEtFOSAA5 ppt< 5< 5
NFDHA20 ppt–< 20
NMeFOSAA6 ppt< 6< 6
PFBA5 ppt–< 5
PFDA3 ppt–< 3
PFDoA3 ppt–< 3
PFEESA3 ppt–< 3
PFHpA3 ppt–< 3
PFHpS3 ppt–< 3
PFHxA3 ppt–< 3
PFMBA3 ppt–< 3
PFMPA4 ppt–< 4
PFNA4 ppt–< 4
PFOA4 ppt–< 4
PFOS4 ppt–< 4
PFPeA3 ppt–< 3
PFPeS4 ppt–< 4
PFTA8 ppt< 8< 8
PFTrDA7 ppt< 7< 7
PFUnA2 ppt–< 2
lithium9 µg/L< 9< 9

Dogwood Slant Wells Composite facility 10016 · sample point 16 · groundwater

CompoundMRL2023-12-06
SE1
2024-04-18
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

Goldmine Slant Wells Composite facility 10017 · sample point 17 · groundwater

CompoundMRL2024-04-10
SE1
2024-04-18
SE2
PFBS3 ppt3.76.6
PFOA4 ppt< 45.5
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
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
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

La Crescenta Well facility 10019 · sample point 19 · groundwater

CompoundMRL2023-11-29
SE1
2024-04-18
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

Lake Plant #5 Well facility 10007 · sample point 07 · groundwater

CompoundMRL2023-11-16
SE1
2024-04-17
SE2
PFBS3 ppt6.49.6
PFHxS3 ppt3.64.3
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
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
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< 910.8

Lake Plant #6 Well facility 10008 · sample point 08 · groundwater

CompoundMRL2023-11-16
SE1
PFBS3 ppt6.5
PFOS4 ppt6.1
11Cl-PF3OUdS5 ppt< 5
4:2 FTS3 ppt< 3
6:2 FTS5 ppt< 5
8:2 FTS5 ppt< 5
9Cl-PF3ONS2 ppt< 2
ADONA3 ppt< 3
HFPO-DA5 ppt< 5
NFDHA20 ppt< 20
PFBA5 ppt< 5
PFDA3 ppt< 3
PFDoA3 ppt< 3
PFEESA3 ppt< 3
PFHpA3 ppt< 3
PFHpS3 ppt< 3
PFHxA3 ppt< 3
PFHxS3 ppt< 3
PFMBA3 ppt< 3
PFMPA4 ppt< 4
PFNA4 ppt< 4
PFOA4 ppt< 4
PFPeA3 ppt< 3
PFPeS4 ppt< 4
PFUnA2 ppt< 2
lithium9 µg/L< 9

Lakewood #7 Well facility 10025 · sample point 25 · groundwater

CompoundMRL2023-12-13
SE1
2024-04-24
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

Lassen #4 Well facility 10014 · sample point 14 · groundwater

CompoundMRL2023-12-06
SE1
2024-02-27
SE2
2024-04-24
SE2
PFBS3 ppt3.3–3.4
PFHxS3 ppt5.9–6.2
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
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
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–

Lassen Slant Wells Composite facility 10015 · sample point 15 · groundwater

CompoundMRL2023-12-06
SE1
2024-04-24
SE2
PFHxS3 ppt56.6
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
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

Magnolia Well facility 10020 · sample point 20 · groundwater

CompoundMRL2023-12-06
SE1
2024-04-24
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

Maple Well facility 10022 · sample point 22 · groundwater

CompoundMRL2023-12-06
SE1
2024-04-24
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

McAllister Well facility 10009 · sample point 09 · groundwater

CompoundMRL2023-11-16
SE1
2024-04-17
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

Middle School Well facility 10011 · sample point 11 · groundwater

CompoundMRL2023-11-16
SE1
2024-04-17
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

Oak Well facility 10010 · sample point 10 · groundwater

CompoundMRL2023-11-16
SE1
2024-04-17
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

Sand Canyon Well facility 10012 · sample point 12 · groundwater

CompoundMRL2023-11-29
SE1
2024-04-18
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

Sawmill Well facility 10021 · sample point 21 · groundwater

CompoundMRL2023-11-29
SE1
2024-04-24
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

Sheephorn Well facility 10013 · sample point 13 · groundwater

CompoundMRL2023-11-29
SE1
2024-04-18
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

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFBS4025%9.6
2024-04-17
1.35–3.6<MRL<MRL6.46.6
PFHxS4020%6.6
2024-04-24
0.98–3.38<MRL<MRL4.35.9
lithium4012%14.5
2024-04-17
1.52–9.4<MRL<MRL10.812.3
PFOA402%5.5
2024-04-18
0.14–4.04<MRL<MRL<MRL<MRL
PFOS402%6.1
2023-11-16
0.15–4.05<MRL<MRL<MRL<MRL

Never detected (25): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFBA, PFDA, PFDoA, PFEESA, PFHpA, PFHpS, PFHxA, PFMBA, PFMPA, PFNA, PFPeA, 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.