SNA (Birmingham) — US military bases spreading cancerous substances was originally seen as an issue primarily for Okinawans to grapple with, but recent discoveries at Yokosuka and Atsugi bases are making clear that it is a nationwide problem.

The dangerous chemicals at issue go by several names. Among these are perfluorooctanesulfonic acid, perfluorooctanoic acid, as well as the broader category of perfluoroalkyl and polyfluoroalkyl substances. But since their full names are quite a mouthful, they will be denoted here by the more manageable acronym PFAS.

PFAS are also sometimes referred to as “forever chemicals” because they can take over a thousand years to degrade. They are commonly used in frying pans and, more relevant to the issue of US military bases, in fire extinguisher foam, aircraft grease, and some water-repellent materials.

These substances quite easily leak into surrounding areas, and this is a problem because, when consumed by humans, they can cause health impacts such as cancer, liver damage, decreased fertility, asthma, and thyroid disease.

It has been widely understood for some years that PFAS contamination is putting residents of Okinawa at potential risk, but on May 4 such contamination was discovered near Yokosuka naval base as well–though it was not reported to the public until July.

Repeated tests since then have confirmed that contaminated wastewater from the base was seeping into the surrounding environment, including into Tokyo Bay.

Testing of the water near the base in late September showed PFAS concentrations up to 258 times higher than the limit imposed by the Ministry of Health.

Yokosuka Mayor Katsuaki Kamiji visited the navy base in October and expressed his view that “the relationship of trust with the US military has been greatly damaged.” US Rear Admiral Carl Lahti offered him an apology, saying, “I’m very sorry. I’m reflecting on it.”

As in all cases relating to dangers to the public posed by US bases, the highly unequal Status of Forces Agreement (SOFA) mandates that the local Japanese authorities have no power to conduct onsite inspections nor to do anything else but to complain. The degree of cooperation, if there is any, is entirely at the discretion of the US military forces, and the outcome usually depends on how insistent is the Ministry of Defense in Tokyo.

In this case, considering its serious nature and the potential political impact, the US military is being to some degree cooperative.

At the beginning of November, the US military informed Yokosuka city that it had started running carbon filters at a drainage treatment facility on the base, and that it hoped this would bring the amount of PFAS contamination below legal limits.

Yokosuka base spokesman Randall Baucom explained: “The US Navy has worked hard to correct this situation. The health and safety of our service members, civilians, their families, and the local community is our top priority. We are committed to learning from this experience and working to make improvements going forward.”

However, at the beginning of this week Japanese government officials conducted an inspection of Naval Air Facility Atsugi, also in Kanagawa Prefecture.

It has been revealed that during a heavy rain on September 24, there was a malfunction at one of the base’s hangars which apparently caused a significant amount of fire extinguisher foam containing PFAS to flow into a small stream that crosses the base.

There has been no explanation why a contamination event which the US military was aware of nearly three months ago is only this week being publicly revealed.

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