Metropolitano

PFAS monitoring results for a public water system in Puerto Rico

PR0002591UCMR 5EPA monitoring data
10.9Highest PFOA result, ppt
7.8Highest PFOS result, ppt
0Highest Hazard Index
600Results
PWSID
PR0002591
State
Puerto Rico
System type
community water system (CWS)
Population served
1,084,637
City
San Juan
Counties
Bayamón Municipio, San Juan Municipio, Toa Alta Municipio
Primary source water
surface water
UCMR 5 sampling
2024-04-04 to 2025-01-22 · 5 entry point(s) · water types: SW
Service-area boundary
authoritative

PFOA 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.

Compared with EPA's 2024 values

Highest single resultWorst entry-point average*Limit
PFOA (ppt)10.92.734
PFOS (ppt)7.86.254
Hazard Index001.0†

“<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 Puerto Rico PFAS drinking-water standard in effect or proposed as of 2026-10-17: No Puerto Rico-specific PFAS drinking-water standard identified (federal NPDWR applies).

Sampling history

Sampled 2024-04-04 to 2025-01-22 · 5 entry point(s) · water types: SW · 20 sampling visits. PFAS in ppt (ng/L).

DateEntry pointEventPFOAPFOSHIOther detections
2024-04-04Canovanas (SW)SE1<4<40none
2024-04-09La Plata Plant (SW)SE1<4<40none
2024-04-17Guaynabo (SW)SE1<45.90PFBA 7
2024-04-17Guaynabo (SW)SE1<450PFBA 8.6, PFHxA 3.5, PFPeA 4
2024-04-17Sergio Cuevas (SW)SE1<46.30PFBA 7.2
2024-07-09Canovanas (SW)SE2<4<40none
2024-07-11Sergio Cuevas (SW)SE25.3<40PFBA 7.3, PFHxA 3.5
2024-07-18Guaynabo (SW)SE2<47.80PFBA 7.6
2024-07-18Guaynabo (SW)SE2<47.60none
2024-07-19La Plata Plant (SW)SE2<4<40none
2024-10-12Sergio Cuevas (SW)SE3<44.40PFPeA 3.1
2024-10-19La Plata Plant (SW)SE3<4<40none
2024-10-23Canovanas (SW)SE3<4<40none
2024-10-30Guaynabo (SW)SE3<45.20none
2024-10-30Guaynabo (SW)SE3<46.10none
2025-01-11Sergio Cuevas (SW)SE4<4<40none
2025-01-13Guaynabo (SW)SE4<45.50none
2025-01-13Guaynabo (SW)SE4<46.30PFBA 5.2
2025-01-15Canovanas (SW)SE410.9<406:2 FTS 49, 8:2 FTS 15.3, PFDA 7.5
2025-01-22La Plata Plant (SW)SE4<4<40none

“<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

600 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.

Canovanas facility 00037 · sample point 2591037 · surface water

CompoundMRL2024-04-04
SE1
2024-07-09
SE2
2024-10-23
SE3
2025-01-15
SE4
6:2 FTS5 ppt< 5< 5< 549
8:2 FTS5 ppt< 5< 5< 515.3
PFDA3 ppt< 3< 3< 37.5
PFOA4 ppt< 4< 4< 410.9
11Cl-PF3OUdS5 ppt< 5< 5< 5< 5
4:2 FTS3 ppt< 3< 3< 3< 3
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
PFBS3 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
PFHxA3 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
PFOS4 ppt< 4< 4< 4< 4
PFPeA3 ppt< 3< 3< 3< 3
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

Guaynabo facility 00035 · sample point 25910308 · surface water

CompoundMRL2024-04-17
SE1
2024-07-18
SE2
2024-10-30
SE3
2025-01-13
SE4
PFBA5 ppt77.6< 5< 5
PFOS4 ppt5.97.85.25.5
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
PFBS3 ppt< 3< 3< 3< 3
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
PFHxA3 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
PFPeA3 ppt< 3< 3< 3< 3
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

Guaynabo facility 00035 · sample point 2591035 · surface water

CompoundMRL2024-04-17
SE1
2024-07-18
SE2
2024-10-30
SE3
2025-01-13
SE4
PFBA5 ppt8.6< 5< 55.2
PFHxA3 ppt3.5< 3< 3< 3
PFOS4 ppt57.66.16.3
PFPeA3 ppt4< 3< 3< 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
PFBS3 ppt< 3< 3< 3< 3
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
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

La Plata Plant facility 00023 · sample point 2591023 · surface water

CompoundMRL2024-04-09
SE1
2024-07-19
SE2
2024-10-19
SE3
2025-01-22
SE4
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
PFBS3 ppt< 3< 3< 3< 3
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
PFHxA3 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
PFPeA3 ppt< 3< 3< 3< 3
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

Sergio Cuevas facility 00040 · sample point 2591040 · surface water

CompoundMRL2024-04-17
SE1
2024-07-11
SE2
2024-10-12
SE3
2025-01-11
SE4
PFBA5 ppt7.27.3< 5< 5
PFHxA3 ppt< 33.5< 3< 3
PFOA4 ppt< 45.3< 4< 4
PFOS4 ppt6.3< 44.4< 4
PFPeA3 ppt< 3< 33.1< 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
PFBS3 ppt< 3< 3< 3< 3
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
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
PFOS2050%7.8
2024-07-18
3–5<MRL5.96.37.6
PFBA2030%8.6
2024-04-17
2.15–5.64<MRL5.27.37.6
PFHxA2010%3.5
2024-04-17
0.35–3.05<MRL<MRL<MRL3.5
PFOA2010%10.9
2025-01-15
0.81–4.41<MRL<MRL<MRL5.3
PFPeA2010%4
2024-04-17
0.35–3.06<MRL<MRL<MRL3.1
6:2 FTS205%49
2025-01-15
2.45–7.2<MRL<MRL<MRL<MRL
8:2 FTS205%15.3
2025-01-15
0.77–5.51<MRL<MRL<MRL<MRL
PFDA205%7.5
2025-01-15
0.38–3.23<MRL<MRL<MRL<MRL

Never detected (22): 11Cl-PF3OUdS, 4:2 FTS, 9Cl-PF3ONS, ADONA, HFPO-DA, NEtFOSAA, NFDHA, NMeFOSAA, PFBS, 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 2023-01-10 to 2026-01-12; 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 9c1cfa699a74 · 2026-10-18T04:05Z · UCMR 5 release Jul2026 · SDWIS 2026Q3. Data and methods.