print PRINT


High concentrations of PFAS detected at three U.S. military facilities in Kanagawa

  • December 11, 2021
  • , Kanagawa Shimbun , p. 21
  • JMH Translation

Original article provided by the Okinawa Times.

By Okinawa Times special correspondent Jon Mitchell


The Okinawa Times learned on Dec. 6 that high levels of per- and polyfluoroalkyl substances (PFAS) had been detected at three U.S. military facilities in Kanagawa Prefecture, including the U.S. Naval Air Facility Atsugi (Ayase City and Yamato City). The highest value of perfluorooctanesulfonic acid (PFOS), which is a type of PFAS, was detected at the Negishi Fire Station in the Negishi district in Yokohama, at 12.1 billion nanograms per liter. The highest value of perfluorooctanoic acid (PFOA), 185 million nanograms per liter, was detected at an oil storage facility at the Atsugi base.


The Okinawa Times obtained this information from a report obtained from the U.S. Navy under the U.S. Freedom of Information Act (FOIA). The Okinawa Times made the FOIA request for the major military bases in Japan and found that the PFAS concentrations in three Kanagawa facilities were noticeably higher [than those in other areas].


PFAS values revealed from U.S. Navy report





Atsugi base

56,000-185 million

184,000-11.3 billion

245,000-1.3 billion

Military fire station in Negishi district

2.56 million – 126 million

82.8 million – 12.1 billion

1.05 million – 2.14 billion

Fuel Terminal Tsurumi

474,000-2.99 million

4 million – 89.2 million

277,000-15.5 million

*Values indicate amount per one liter of water in nanograms.


The level of PFAS from foam extinguishers that have been diluted or mixed with water from waterways and rivers has become an issue in Okinawa. This report showed that the PFAS content of foam fire extinguishing agents stored in the base is much higher [than those in waterways and rivers].


According to the report, the U.S. Navy conducted a total of 33 inspections of tanks containing foam fire extinguishing agents, such as those in hangars, oil storage facilities, and fire engines, in November and December 2018. All samples far exceeded Japan’s provisional benchmark values (50 nanograms per liter for PFOS and PFOA combined).


A high value of PFHxS, a substance similar to PFAS but which has no benchmark value, was also confirmed. It is not known if the tank contained a foam fire extinguishing agent at the time of inspection.


In November 2020, the U.S. Navy also inspected the Atsugi base’s drinking water, which is drawn from groundwater. The PFOS and PFOA in the drinking water measured only 24 nanograms per liter.


A possible cause of pollution in surrounding areas

The U.S. Navy report obtained by the Okinawa Times suggests that the high level of PFAS detected at Atsugi base may have affected the environment outside the base. Between 2009 and 2016, there were at least five large-scale incidents at Atsugi which involved foam extinguishers, some of which contained PFOS and similar chemicals.


According to the report, a large-scale fire broke out in a hangar at the base in November 2009. About 15,000 liters of wastewater was generated in extinguishing the fire. The wastewater was discharged from the base’s sewage treatment plant.


In 2018, a Navy survey took a sample from the fire extinguishing system at the same hangar and found that the PFOS and PFOA concentrations were 4 million and 3.45 million nanograms per liter, respectively.


These values indicate that the source of the pollution around the military base, which were detected in Japanese government surveys, lies inside the bases.


The Ministry of the Environment announced in June 2020 that 239 nanograms of PFOS was detected in the Hikiji River, which flows near the Atsugi base. This value is more than four times Japan’s provisional benchmark value. In June 2021, the groundwater in Ayase City was found to be contaminated with 1,300 nanograms of PFOS. This value was the highest value of PFOS detected in groundwater surveys nationwide.


The Okinawa Times asked U.S. Naval Forces Japan about these instances of PFAS contamination. The Navy responded that it “complies with the Japanese Environmental Management Standards (JEGS)” and that it will “notify the Japanese government if there is a possibility of environmental impact on the surrounding area” but did not respond with respect to individual cases.

  • Ambassador
  • Ukraine
  • COVID-19
  • Trending Japan