Goose Creek City Of (Sc0810004)

PFAS monitoring results for a public water system in South Carolina

SC0810004UCMR 5EPA monitoring data
5.8Highest PFOA result, ppt
7.2Highest PFOS result, ppt
0.682Highest Hazard Index
66Results
PWSID
SC0810004
State
South Carolina
System type
community water system (CWS)
Population served
43,744
City
Goose Creek
Counties
Berkeley County
Primary source water
surface water (purchased)
UCMR 5 sampling
2024-09-19 to 2026-03-16 · 1 entry point(s) · water types: SW
Service-area boundary
EPA-modeled (Random Forest) — approximate: estimated by EPA with a statistical model, not a surveyed service area

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.

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)5.85.254
PFOS (ppt)7.26.054
Hazard Index0.6820.3421.0†

“<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 2024-09-19 to 2026-03-16 · 1 entry point(s) · water types: SW · 5 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2024-09-19Santee Cooper - Connection (SW)SE14.74.90.002PFHxA 5.2, PFPeA 6.5
2024-12-02Santee Cooper - Connection (SW)SE2n/an/an/anone
2025-03-14Santee Cooper - Connection (SW)SE3n/an/an/anone
2025-06-04Santee Cooper - Connection (SW)SE4n/an/an/anone
2026-03-16Santee Cooper - Connection (SW)SE45.87.20.682PFHxA 6.1, PFPeA 6.6

“<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

66 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.

Santee Cooper - Connection facility 08130 · sample point P08130 · surface water

CompoundMRL2024-09-19
SE1
2024-12-02
SE2
2025-03-14
SE3
2025-06-04
SE4
2026-03-16
SE4
HFPO-DA5 ppt< 5–––6.8
PFBS3 ppt3.3–––4.8
PFHxA3 ppt5.2–––6.1
PFOA4 ppt4.7–––5.8
PFOS4 ppt4.9–––7.2
PFPeA3 ppt6.5–––6.6
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
NEtFOSAA5 ppt< 5< 5–< 5–
NFDHA20 ppt< 20–––< 20
NMeFOSAA6 ppt< 6< 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
PFHxS3 ppt< 3–––< 3
PFMBA3 ppt< 3–––< 3
PFMPA4 ppt< 4–––< 4
PFNA4 ppt< 4–––< 4
PFPeS4 ppt< 4–––< 4
PFTA8 ppt< 8< 8–< 8–
PFTrDA7 ppt< 7< 7–< 7–
PFUnA2 ppt< 2–––< 2
lithium9 µg/L< 9< 9< 9< 9–

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFBS2100%4.8
2026-03-16
4.05–4.05fewer than 4 results: raw values only
PFHxA2100%6.1
2026-03-16
5.65–5.65fewer than 4 results: raw values only
PFOA2100%5.8
2026-03-16
5.25–5.25fewer than 4 results: raw values only
PFOS2100%7.2
2026-03-16
6.05–6.05fewer than 4 results: raw values only
PFPeA2100%6.6
2026-03-16
6.55–6.55fewer than 4 results: raw values only
HFPO-DA250%6.8
2026-03-16
3.4–5.9fewer than 4 results: raw values only

Never detected (24): 11Cl-PF3OUdS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 9Cl-PF3ONS, ADONA, NEtFOSAA, NFDHA, NMeFOSAA, PFBA, PFDA, PFDoA, PFEESA, PFHpA, PFHpS, PFHxS, 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.