Clayton County Water Authority

PFAS monitoring results for a public water system in Georgia

GA0630000UCMR 5EPA monitoring data
8.4Highest PFOA result, ppt
8.5Highest PFOS result, ppt
0.663Highest Hazard Index
360Results
PWSID
GA0630000
State
Georgia
System type
community water system (CWS)
Population served
298,374
City
Morrow
Counties
Clayton County, Fayette County, Fulton County, Henry County
Primary source water
surface water
UCMR 5 sampling
2023-02-15 to 2023-11-06 · 3 entry point(s) · water types: SW
Service-area boundary
authoritative

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

  • Atlanta (GA1210001)
    Seller's highest results: PFOA <MRL · PFOS <MRL · HI 0.002 · detected: PFBA;PFBS;PFHxA;PFPeA
  • Dekalb County (GA0890001)
    Seller's highest results: PFOA <MRL · PFOS <MRL · HI 0

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)8.46.64
PFOS (ppt)8.57.14
Hazard Index0.6630.481.0†

“<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).

Sampling history

Sampled 2023-02-15 to 2023-11-06 · 3 entry point(s) · water types: SW · 12 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2023-02-15Atlanta (SW)SE1<4<40.002PFHxA 3.8, PFPeA 3.5
2023-02-15Noah`s Ark Tank Farm (SW)SE15.58.50.6636:2 FTS 5.3, PFHpA 4.3, PFHxA 10, PFPeA 11
2023-02-15William Hooper Filter Plant (SW)SE15.15.20.313PFHpA 3.5, PFHxA 8.8, PFPeA 8.5
2023-05-03Atlanta (SW)SE2<4<40none
2023-05-03Noah`s Ark Tank Farm (SW)SE256.10.392PFHpA 4, PFHxA 9, PFPeA 9.3
2023-05-03William Hooper Filter Plant (SW)SE25.45.60.002PFHpA 3.4, PFHxA 7.4, PFPeA 7.4
2023-08-09Atlanta (SW)SE3<4<40PFHxA 3.2, PFPeA 3.4
2023-08-09Noah`s Ark Tank Farm (SW)SE36.27.60.473PFBA 5.1, PFHpA 4.6, PFHxA 12, PFPeA 12
2023-08-09William Hooper Filter Plant (SW)SE37.58.10.363PFBA 5.5, PFHpA 5.1, PFHxA 13, PFPeA 13
2023-11-06Atlanta (SW)SE4<4<40PFPeA 3.3
2023-11-06Noah`s Ark Tank Farm (SW)SE47.16.20.393PFBA 6.8, PFHpA 4.9, PFHxA 14, PFPeA 16
2023-11-06William Hooper Filter Plant (SW)SE48.47.50.363PFBA 6.3, PFHpA 5.5, PFHxA 16, PFPeA 18

“<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.

Atlanta facility 11113 · sample point 305 · surface water

CompoundMRL2023-02-15
SE1
2023-05-03
SE2
2023-08-09
SE3
2023-11-06
SE4
PFBS3 ppt3.7< 3< 3< 3
PFHxA3 ppt3.8< 33.2< 3
PFPeA3 ppt3.5< 33.43.3
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
PFBA5 ppt< 5< 5< 5< 5
PFDA3 ppt< 3< 3< 3< 3
PFDoA3 ppt< 3< 3< 3< 3
PFEESA3 ppt< 3< 3< 3< 3
PFHpA3 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
PFOA4 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

Noah`s Ark Tank Farm facility 16130 · sample point 302 · surface water

CompoundMRL2023-02-15
SE1
2023-05-03
SE2
2023-08-09
SE3
2023-11-06
SE4
6:2 FTS5 ppt5.3< 5< 5< 5
PFBA5 ppt< 5< 55.16.8
PFBS3 ppt6.54.35.45.7
PFHpA3 ppt4.344.64.9
PFHxA3 ppt1091214
PFHxS3 ppt6.63.94.73.9
PFOA4 ppt5.556.27.1
PFOS4 ppt8.56.17.66.2
PFPeA3 ppt119.31216
11Cl-PF3OUdS5 ppt< 5< 5< 5< 5
4:2 FTS3 ppt< 3< 3< 3< 3
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
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< 8
PFTrDA7 ppt< 7< 7< 7< 7
PFUnA2 ppt< 2< 2< 2< 2
lithium9 µg/L< 9< 9< 9< 9

William Hooper Filter Plant facility 00574 · sample point 301 · surface water

CompoundMRL2023-02-15
SE1
2023-05-03
SE2
2023-08-09
SE3
2023-11-06
SE4
PFBA5 ppt< 5< 55.56.3
PFBS3 ppt6.445.65.4
PFHpA3 ppt3.53.45.15.5
PFHxA3 ppt8.87.41316
PFHxS3 ppt3.1< 33.63.6
PFOA4 ppt5.15.47.58.4
PFOS4 ppt5.25.68.17.5
PFPeA3 ppt8.57.41318
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
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< 8
PFTrDA7 ppt< 7< 7< 7< 7
PFUnA2 ppt< 2< 2< 2< 2
lithium9 µg/L< 9< 9< 9< 9

Statistics by compound

CompoundResultsDetectedHighest (date)Mean boundsKM medianP75P90P95
PFPeA1292%18
2023-11-06
8.78–9.038.5121618
PFHxA1283%16
2023-11-06
8.1–8.68.8121416
PFBS1275%6.5
2023-02-15
3.92–4.674.35.66.46.5
PFHpA1267%5.5
2023-11-06
2.94–3.943.54.65.15.5
PFOA1267%8.4
2023-11-06
4.18–5.525.16.27.58.4
PFOS1267%8.5
2023-02-15
4.57–5.95.67.58.18.5
PFHxS1258%6.6
2023-02-15
2.45–3.73.13.94.76.6
PFBA1233%6.8
2023-11-06
1.98–5.31<MRL5.16.36.8
6:2 FTS128%5.3
2023-02-15
0.44–5.03<MRL<MRL<MRL5.3

Never detected (21): 11Cl-PF3OUdS, 4:2 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 2023-01-09 to 2026-06-17; 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 e0e919e2a26a · 2026-10-18T04:09Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.