PROJECT ABACUSENVIRONMENTAL DATA

Waite Park

PFAS monitoring results for a public water system in Minnesota

MN1730039UCMR 5EPA monitoring data
5.5Highest PFOA result, ppt
18Highest PFOS result, ppt
1.702Highest Hazard Index
60Results
PWSID
MN1730039
State
Minnesota
System type
community water system (CWS)
Population served
8,354
City
Waite Park
Counties
Stearns County
Primary source water
groundwater
UCMR 5 sampling
2023-05-01 to 2023-11-28 · 1 entry point(s) · water types: GW
Service-area boundary
authoritative

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

Open on the Minnesota map · All Minnesota systems · All results

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

  • Saint Cloud (MN1730027)
    Seller's highest results: PFOA <MRL · PFOS <MRL · HI 0 · detected: PFBA

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)5.55.454
PFOS (ppt)1816.54
Hazard Index1.7021.6521.0†

“<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 Minnesota guidance levels

Highest single resultWorst entry-point average*Minnesota
PFOA (ppt)5.55.450.01 (guidance)
PFOS (ppt)1816.52.3 (guidance)
PFHxS (ppt)1716.547 (guidance)
PFBS (ppt)4.64.45100 (guidance)
PFHxA (ppt)87.35200 (guidance)
PFBA (ppt)1211.57,000 (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 2023-05-01 to 2023-11-28 · 1 entry point(s) · water types: GW · 2 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2023-05-01TREATMENT PLANT #2 (GW)SE15.4151.602PFBA 11, PFHpA 3.4, PFHxA 6.7, PFPeA 9.5
2023-11-28TREATMENT PLANT #2 (GW)SE25.5181.702PFBA 12, PFHpA 3.6, PFHxA 8, PFPeA 12

“<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.

TREATMENT PLANT #2 facility 7 · sample point E02 · groundwater

CompoundMRL2023-05-01
SE1		2023-11-28
SE2
PFBA5 ppt1112
PFBS3 ppt4.34.6
PFHpA3 ppt3.43.6
PFHxA3 ppt6.78
PFHxS3 ppt1617
PFOA4 ppt5.45.5
PFOS4 ppt1518
PFPeA3 ppt9.512
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
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

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFBA2100%12
2023-11-28		11.5–11.5fewer than 4 results: raw values only
PFBS2100%4.6
2023-11-28		4.45–4.45fewer than 4 results: raw values only
PFHpA2100%3.6
2023-11-28		3.5–3.5fewer than 4 results: raw values only
PFHxA2100%8
2023-11-28		7.35–7.35fewer than 4 results: raw values only
PFHxS2100%17
2023-11-28		16.5–16.5fewer than 4 results: raw values only
PFOA2100%5.5
2023-11-28		5.45–5.45fewer than 4 results: raw values only
PFOS2100%18
2023-11-28		16.5–16.5fewer than 4 results: raw values only
PFPeA2100%12
2023-11-28		10.75–10.75fewer 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, PFMBA, PFMPA, PFNA, PFPeS, PFTA, PFTrDA, PFUnA, lithium.

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 2023-01-04 to 2026-02-23; 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 b4430eb8fd55 · 2026-10-18T04:07Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.