Finale Partners

PFAS monitoring results for a public water system in Pennsylvania

PA1090329UCMR 5EPA monitoring data
16.8Highest PFOA result, ppt
9.7Highest PFOS result, ppt
0.003Highest Hazard Index
60Results
PWSID
PA1090329
State
Pennsylvania
System type
non-transient non-community water system (NTNCWS)
Population served
150
City
New Hope
Counties
Bucks County
Primary source water
groundwater
UCMR 5 sampling
2024-06-19 to 2024-12-16 · 1 entry point(s) · water types: GW
Service-area boundary
parcel-based (EPA non-community layer)

PFOA ≥ 3 × its limit highest single result
PFOA ≥ 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)16.812.554
PFOS (ppt)9.79.64
Hazard Index0.0030.0021.0†

“<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 Pennsylvania standards

Highest single resultWorst entry-point average*Pennsylvania
PFOA (ppt)16.812.5514
PFOS (ppt)9.79.618

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 2024-06-19 to 2024-12-16 · 1 entry point(s) · water types: GW · 2 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2024-06-19ENTRY POINT ONE (GW)SE18.39.70.002PFHxA 3.1, PFPeA 3.2, lithium 16.5 µg/L
2024-12-16ENTRY POINT ONE (GW)SE216.89.50.003PFBA 7.9, PFHpA 6.5, PFHxA 9.4, PFPeA 9.7, lithium 9.77 µg/L

“<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

60 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.

ENTRY POINT ONE facility 101 · sample point E · groundwater

CompoundMRL2024-06-19
SE1
2024-12-16
SE2
PFBA5 ppt< 57.9
PFBS3 ppt45.2
PFHpA3 ppt< 36.5
PFHxA3 ppt3.19.4
PFOA4 ppt8.316.8
PFOS4 ppt9.79.5
PFPeA3 ppt3.29.7
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
PFDA3 ppt< 3< 3
PFDoA3 ppt< 3< 3
PFEESA3 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/L16.59.77

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFBS2100%5.2
2024-12-16
4.6–4.6fewer than 4 results: raw values only
PFHxA2100%9.4
2024-12-16
6.25–6.25fewer than 4 results: raw values only
PFOA2100%16.8
2024-12-16
12.55–12.55fewer than 4 results: raw values only
PFOS2100%9.7
2024-06-19
9.6–9.6fewer than 4 results: raw values only
PFPeA2100%9.7
2024-12-16
6.45–6.45fewer than 4 results: raw values only
lithium2100%16.5
2024-06-19
13.13–13.13fewer than 4 results: raw values only
PFBA250%7.9
2024-12-16
3.95–6.45fewer than 4 results: raw values only
PFHpA250%6.5
2024-12-16
3.25–4.75fewer than 4 results: raw values only

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 2023-01-10 to 2026-04-09; 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 52bd2907cbc3 · 2026-10-18T04:10Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.