1341613

❶ ALPS treated water, etc. Reduction Status

Amount of ALPS treated water, etc.

0reduction

since the commencement of
ALPS treated water discharge (August 2023)

Prior to the commencement of ALPS treated water discharge 1,336,502㎥

1297499

*Amount of water containing amount between the bottom of
a tank and the lower measuring limit of the level gauge
The process of generating ALPS-treated water

At the Fukushima Daiichi Nuclear Power Station, ALPS treated water, etc. (" ALPS treated water" and "water to be re-purified"), which is contaminated water that has been treated with multi-nuclide removal equipment (ALPS), is stored. And, water awaiting ALPS treated is also temporarily stored.
・ALPS treated water
Before each ALPS treated water discharge, we confirm that government standards for discharge into the environment have been met.
・Water to be re-purified
Before treated water to be re-purified is discharged into the sea, it is repeatedly purified with ALPS until government standards are met.

Radioactive Concentration Contains in ALPS treated water, etc.

  • 34%
    (404,500m³)
  • 30%
    (351,200m³)
  • 18%
    (209,600m³)
  • 14%
    (161,700m³)
  • 5%
    (56,700m³)

A L P S t r e a t e d w a t e r

W a t e r t o b e - p u r i f i e d

(As of December 31, 2024)

*Only completely filled tanks were used to calculate the amount, so this amount may differ from the entire amount of stored water.

Amount of ALPS treated water and water to be re-purified broken down by the sum of the ratios to regulatory concentrations limits (estimate)

  • 〜1time
  • 1time〜5times
  • 5times〜10times
  • 10times〜100times
  • 100times〜19,909times
  • Sum may not be 100 because storage percentages have been rounded to integers.

Currently, ALPS treated water, etc. is being stored in tanks after most of the radionuclides have been removed, with the exception of tritium. Multi-nuclide removal equipment is capable of removing radioactive substances (excluding tritium) to the point where the concentrations of these substances are lower than the regulatory concentrations limits set for discharge into the environment, which are part of national regulatory standards pertaining to contaminated water. However, due to equipment malfunctions at the beginning of the facility operation and different operational objectives at the time , the current amount of treated water being stored broken down by the sum of the ratios to regulatory concentrations is as shown in the above diagram.