PFAS in Guam tap water

1 of 5 tested systems measured above the federal limit. 3 had a detection of any kind.

Every public water system below was required by the EPA to test for 29 PFAS compounds. Sorted by the highest PFOA or PFOS reading, worst first. Find yours for the full set of readings and what removes them.

Water systemHighest PFOAHighest PFOSFoundAgainst the 4 ppt limit
Gwa Northern Water System18.3 ppt135 ppt11 of 29Above
Andersen Air Force Base Water Systemnone detectednone detected3 of 29Within
Gwa Central Water Systemnone detectednone detected0 of 29Within
Gwa Southern Water Systemnone detectednone detected0 of 29Within
U.s. Navy Water Systemnone detectednone detected1 of 29Within

All 5 systems the EPA tested in Guam, every one of them with its own page. Each was tested for 29 PFAS compounds.

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Source, the EPA’s fifth Unregulated Contaminant Monitoring Rule, final dataset published 2026-10-15. Original data →