Overview
- White foam erupted from a manhole in Isa 1‑chome, Ginowan, on January 29.
- Combined PFOS and PFOA measured about 268 nanograms per liter, exceeding Japan’s provisional guideline of 50 ng/L by more than fivefold.
- A local citizen group collected the foam and commissioned Kyoto Prefectural University professor Koji Harada to conduct the analysis.
- Ginowan City says the sewer under the manhole connects to the nearby U.S. Futenma Air Station.
- Harada said the foam’s composition differs from a 2020 firefighting‑foam leak and warned PFAS may be continually flowing from inside the base, with no official source attribution or remediation reported.