Clinton City Of (Sc3010002)

PFAS monitoring results for a public water system in South Carolina

SC3010002UCMR 5EPA monitoring data
8Highest PFOA result, ppt
8.1Highest PFOS result, ppt
1.435Highest Hazard Index
116Results
PWSID
SC3010002
State
South Carolina
System type
community water system (CWS)
Population served
8,938
City
Clinton
Counties
Laurens County
Primary source water
surface water
UCMR 5 sampling
2023-10-23 to 2024-07-10 · 1 entry point(s) · water types: SW
Service-area boundary
EPA-modeled (Decision Tree) — approximate: estimated by EPA with a statistical model, not a surveyed service area

PFOS 1–3 × 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.

Compared with EPA's 2024 values

Highest single resultWorst entry-point average*Limit
PFOA (ppt)86.724
PFOS (ppt)8.16.284
Hazard Index1.4350.5791.0†

“<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).

No South Carolina PFAS drinking-water standard in effect or proposed as of 2026-10-17: No state PFAS drinking-water standard; H. 3116 and H. 5572 (2025-26) pending, not enacted.

Sampling history

Sampled 2023-10-23 to 2024-07-10 · 1 entry point(s) · water types: SW · 6 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2023-10-23CLINTON CITY OF (3010002) (SW)SE17.15.90.358PFBA 9.3, PFHpA 3.8, PFHxA 32.9, PFPeA 39.9
2024-01-23CLINTON CITY OF (3010002) (SW)SE27.16.40.007PFHxA 9.1, PFPeA 9.4
2024-03-19CLINTON CITY OF (3010002) (SW)SE1n/an/an/anone
2024-04-16CLINTON CITY OF (3010002) (SW)SE3n/an/an/anone
2024-05-14CLINTON CITY OF (3010002) (SW)SE34.74.70.514PFHxA 7.8, PFPeA 11.2
2024-07-10CLINTON CITY OF (3010002) (SW)SE488.11.435PFBA 7.5, PFHpA 4, PFHxA 20.6, PFPeA 27.1

“<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

116 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.

CLINTON CITY OF (3010002) facility A30002 · sample point A30002 · surface water

CompoundMRL2023-10-23
SE1
2024-01-23
SE2
2024-03-19
SE1
2024-04-16
SE3
2024-05-14
SE3
2024-07-10
SE4
HFPO-DA5 ppt< 5< 5––5.114.3
PFBA5 ppt9.3< 5––< 57.5
PFBS3 ppt15.613.9––8.610.4
PFHpA3 ppt3.8< 3––< 34
PFHxA3 ppt32.99.1––7.820.6
PFHxS3 ppt3.5< 3––< 3< 3
PFOA4 ppt7.17.1––4.78
PFOS4 ppt5.96.4––4.78.1
PFPeA3 ppt39.99.4––11.227.1
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
NEtFOSAA5 ppt––< 5< 5–< 5
NFDHA20 ppt< 20< 20––< 20< 20
NMeFOSAA6 ppt––< 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
PFMBA3 ppt< 3< 3––< 3< 3
PFMPA4 ppt< 4< 4––< 4< 4
PFNA4 ppt< 4< 4––< 4< 4
PFPeS4 ppt< 4< 4––< 4< 4
PFTA8 ppt––< 8< 8–< 8
PFTrDA7 ppt––< 7< 7–< 7
PFUnA2 ppt< 2< 2––< 2< 2
lithium9 µg/L< 9< 9–< 9–< 9

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFBS4100%15.6
2023-10-23
12.12–12.1210.413.915.615.6
PFHxA4100%32.9
2023-10-23
17.6–17.69.120.632.932.9
PFOA4100%8
2024-07-10
6.72–6.727.17.188
PFOS4100%8.1
2024-07-10
6.28–6.285.96.48.18.1
PFPeA4100%39.9
2023-10-23
21.9–21.911.227.139.939.9
HFPO-DA450%14.3
2024-07-10
4.85–7.35<MRL5.114.314.3
PFBA450%9.3
2023-10-23
4.2–6.7<MRL7.59.39.3
PFHpA450%4
2024-07-10
1.95–3.45<MRL3.844
PFHxS425%3.5
2023-10-23
0.88–3.12<MRL<MRL3.53.5

Never detected (21): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, 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 2023-01-09 to 2026-06-15; 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 04c4b5704fe9 · 2026-10-18T04:07Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.