Mahwah Water Department

PFAS monitoring results for a public water system in New Jersey

NJ0233001UCMR 5EPA monitoring data
12.5Highest PFOA result, ppt
4.5Highest PFOS result, ppt
0.002Highest Hazard Index
360Results
PWSID
NJ0233001
State
New Jersey
System type
community water system (CWS)
Population served
26,777
City
Mahwah
Counties
Bergen County
Primary source water
surface water
UCMR 5 sampling
2024-10-02 to 2026-01-21 · 5 entry point(s) · water types: GW;SW
Service-area boundary
EPA-modeled (Random Forest) — approximate: estimated by EPA with a statistical model, not a surveyed service area

PFOA ≥ 3 × its limit highest single result
PFOA 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)12.510.854
PFOS (ppt)4.54.44
Hazard Index0.0020.0011.0†

“<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 New Jersey standards

Highest single resultWorst entry-point average*New Jersey
PFNA (ppt)0013
PFOA (ppt)12.510.8514
PFOS (ppt)4.54.413

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 2024-10-02 to 2026-01-21 · 5 entry point(s) · water types: GW;SW · 14 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2024-10-02Ford Wells TP (GW)SE1<4<40lithium 33.1 µg/L
2024-10-02Veolia Water Consecutive Connection (SW)SE18.7<40PFHxA 4.4, PFPeA 4.4
2024-10-02Well 16 TP (GW)SE1n/an/an/anone
2024-10-02Well 17 TP (GW)SE1n/an/an/anone
2024-10-29Well 16 TP (GW)SE18.44.30PFHxA 3.7, PFPeA 3.8
2024-10-29Well 17 TP (GW)SE18.24.30PFBA 5.1, PFHxA 3.5, PFPeA 3.9
2025-01-14Veolia Water Consecutive Connection (SW)SE210.4<40.002PFBA 5.6, PFHpA 3.6, PFHxA 5.5, PFPeA 5.4
2025-04-09Ford Wells TP (GW)SE2<4<40none
2025-04-09Veolia Water Consecutive Connection (SW)SE311.8<40.002PFBA 6, PFHpA 3.6, PFHxA 5.7, PFPeA 5.6
2025-04-09Well 17 TP (GW)SE28.14.50PFBA 5, PFHxA 3.3, PFPeA 3.7
2025-05-28Well 16 TP (GW)SE27.24.10PFHxA 3, PFPeA 3.3
2025-07-08Veolia Water Consecutive Connection (SW)SE412.5<40.002PFBA 6, PFHpA 3.9, PFHxA 6.1, PFPeA 6.1
2025-08-12Well 19 TP (GW)SE1<4<40none
2026-01-21Well 19 TP (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

360 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.

Ford Wells TP facility 11012 · sample point TP011012 · groundwater

CompoundMRL2024-10-02
SE1
2025-04-09
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/L33.1< 9

Veolia Water Consecutive Connection facility 30001 · sample point CC230001 · surface water

CompoundMRL2024-10-02
SE1
2025-01-14
SE2
2025-04-09
SE3
2025-07-08
SE4
PFBA5 ppt< 55.666
PFBS3 ppt< 33.63.54.1
PFHpA3 ppt< 33.63.63.9
PFHxA3 ppt4.45.55.76.1
PFOA4 ppt8.710.411.812.5
PFPeA3 ppt4.45.45.66.1
11Cl-PF3OUdS5 ppt< 5< 5< 5< 5
4:2 FTS3 ppt< 3< 3< 3< 3
6:2 FTS5 ppt< 5< 5< 5< 5
8:2 FTS5 ppt< 5< 5< 5< 5
9Cl-PF3ONS2 ppt< 2< 2< 2< 2
ADONA3 ppt< 3< 3< 3< 3
HFPO-DA5 ppt< 5< 5< 5< 5
NEtFOSAA5 ppt< 5< 5< 5< 5
NFDHA20 ppt< 20< 20< 20< 20
NMeFOSAA6 ppt< 6< 6< 6< 6
PFDA3 ppt< 3< 3< 3< 3
PFDoA3 ppt< 3< 3< 3< 3
PFEESA3 ppt< 3< 3< 3< 3
PFHpS3 ppt< 3< 3< 3< 3
PFHxS3 ppt< 3< 3< 3< 3
PFMBA3 ppt< 3< 3< 3< 3
PFMPA4 ppt< 4< 4< 4< 4
PFNA4 ppt< 4< 4< 4< 4
PFOS4 ppt< 4< 4< 4< 4
PFPeS4 ppt< 4< 4< 4< 4
PFTA8 ppt< 8< 8< 8< 8
PFTrDA7 ppt< 7< 7< 7< 7
PFUnA2 ppt< 2< 2< 2< 2
lithium9 µg/L< 9< 9< 9< 9

Well 16 TP facility 16025 · sample point TP016025 · groundwater

CompoundMRL2024-10-02
SE1
2024-10-29
SE1
2025-05-28
SE2
PFHxA3 ppt–3.73
PFOA4 ppt–8.47.2
PFOS4 ppt–4.34.1
PFPeA3 ppt–3.83.3
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
PFHpA3 ppt–< 3< 3
PFHpS3 ppt–< 3< 3
PFHxS3 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 17 TP facility 17027 · sample point TP017027 · groundwater

CompoundMRL2024-10-02
SE1
2024-10-29
SE1
2025-04-09
SE2
PFBA5 ppt–5.15
PFHxA3 ppt–3.53.3
PFOA4 ppt–8.28.1
PFOS4 ppt–4.34.5
PFPeA3 ppt–3.93.7
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
PFBS3 ppt–< 3< 3
PFDA3 ppt–< 3< 3
PFDoA3 ppt–< 3< 3
PFEESA3 ppt–< 3< 3
PFHpA3 ppt–< 3< 3
PFHpS3 ppt–< 3< 3
PFHxS3 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 19 TP facility 19051 · sample point TP019051 · groundwater

CompoundMRL2025-08-12
SE1
2026-01-21
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
PFHxA1267%6.1
2025-07-08
2.93–3.933.34.45.76.1
PFOA1267%12.5
2025-07-08
6.28–7.618.18.711.812.5
PFPeA1267%6.1
2025-07-08
3.02–4.023.74.45.66.1
PFBA1242%6
2025-04-09
2.31–5.22<MRL5.166
PFOS1233%4.5
2025-04-09
1.43–4.1<MRL4.14.34.5
PFBS1225%4.1
2025-07-08
0.93–3.18<MRL<MRL3.64.1
PFHpA1225%3.9
2025-07-08
0.93–3.17<MRL<MRL3.63.9
lithium128%33.1
2024-10-02
2.76–11.01<MRL<MRL<MRL33.1

Never detected (22): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFDA, PFDoA, PFEESA, PFHpS, PFHxS, 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 2026-05-29; 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 0c4398dd12d6 · 2026-10-18T04:09Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.