By Toume Chie
The cost of upgrading Chatan water purification plant will increase from the 1.3 billion yen originally estimated to approximately 1.6 billion yen in order to allow for more efficient removal of per- and polyfluoroalkyl substances (PFAS), the Ryukyu Shimpo learned by May 8.
The Chatan water purification plant is operated by Okinawa Prefecture’s Enterprise Bureau. The presence of PFAS has been detected in one of the plant’s water sources that runs near a U.S. base, and the substance is suspected to have originated from the base.
“We are not familiar with any water treatment plant in Japan that has introduced active carbon to specifically treat PFAS,” says the bureau’s official in charge of the issue.
The original construction plan was altered to improve its purification capacity using granular active carbon, which is effective in absorbing PFAS and other chemical compounds. Subsidies from the Defense Ministry will cover two-thirds of the 1.6 billion yen (approximately 1.06 billion yen) and the prefecture’s enterprise bureau will pay one-third from its budget that comes from residents’ water supply charges.
Separately, the Okinawa Defense Bureau, which subsidizes the anti-PFAS measures taken at the Chatan water purification plant, said in response to an inquiry from the Ryukyu Shimpo: “At this point, causality between U.S. military activities and substances such as PFOS has not been established in the opinion of the Defense Ministry. We have not reached the conclusion that the compensation is required in this circumstance.” (Abridged)