The Ministry of Internal Affairs and Communications has asked the Ministry of the Environment to promote the replacement of septic tanks. Septic tanks, which purify domestic wastewater before discharging it into rivers, are installed in homes in areas without sewage treatment facilities.
Even if they become old and have environmental or sanitary problems, they are expensive to replace. Only four local governments had determined whether there were any problems as of FY2021 is. The Ministry of Environment said, ``We will consider the recommendations and take necessary measures''