In 2016, Okinawa Prefecture announced that it had detected high levels of PFAS in rivers and wells in and around Kadena Air Base – and subsequent tests have confirmed severe contamination in this water system which provides drinking water to 450,000 residents. But the Japanese and US governments have insisted that it is impossible to confirm the source of the problem.
Now, documents obtained by Okinawa Times suggest the origin of the contamination is likely a former firefighter training area located within Kadena Air Base which was used during the 1970s and 1980s. According to hearings held in 1985 by the US House Committee on Armed Services, the site had no pollution controls; this raises concerns firefighting foam would have soaked into the ground or flowed into nearby waterways. Archive photographs show the training area was located approximately 50 meters west of Dakujaku River, which is a PFAS hotspot, today.
Throughout this period, it was normal for the USAF to conduct training with firefighting foams containing PFAS. Overseas, checks on former firefighter training areas have revealed severe PFAS contamination reaching tens of meters underground and plumes of contamination spreading below the ground for several kilometers.
On Kadena Air Base, today a building for aircraft maintenance sits atop the site of where the firefighter training area used to be. According to USAF maps obtained via the US Freedom of Information Act (FOIA), water flows above and below ground from this site into Dakujaku River and towards three groundwater wells.
Test results announced by Japan’s Ministry of the Environment on 11 June 2020 revealed Dakujaku River was contaminated with PFOS at 1462 ng/L, the highest in the nation, far exceeding the ministry’s 50 ng/L guideline for rivers. According to checks by Okinawa Enterprise Bureau, wells located in the vicinity are also severely contaminated. The wells and Hija River, into which Dakujaku River flows, contribute to the drinking water for 450,000 residents.
The US military in Japan claims its responsibility for the contamination cannot be proven, and it has denied requests from Okinawa Prefecture to conduct environmental checks within Kadena Air Base.
On 15 June 2020, Okinawa Times asked USAF for comment about the issues raised in this article. On 29 December 2020, USAF 18th Wing Public Affairs finally admitted the former firefighter training area had consisted of a two-story concrete structure and a pit which had been demolished at an unspecified time in the past. According to USAF, it had not conducted any surveys for PFAS at the site; in the same statement, it also said, “The possible source or sources of contamination in the Dakujakugawa and the groundwater wells has not been determined.”
When asked whether the US military would allow Japanese and/or Prefectural authorities to access the site to survey for PFAS contamination, a United States Forces Japan spokesperson refrained from answering, instead stating that such requests were dealt with by the US-Japan Joint Committee.
As of March 2020, the Department of Defense suspected 651 military bases in the United States might be contaminated from the usage of PFAS firefighting foams. Moreover, it has admitted to PFAS contamination at its overseas facilities, notably in Belgium, Honduras, South Korea and Germany.
Internal reports obtained by this newspaper under FOIA reveal PFAS contamination at US facilities in Japan include Kadena Air Base, MCAS Futenma, NAF Atsugi, Kanagawa Prefecture, Yokota Air Base, Tokyo, and Misawa Air Base, Aomori Prefecture,
（日本語関連記事） 80年代の消火訓練場が汚染源か 嘉手納の高濃度PFOS