(Specific methods for landfill are elaborated) What is the Landfill Facility for the Specified Waste? (Vol. 2)

(The picture above is for illustrative purpose)

Hello, everyone. My name is Daichi, an expert providing the information on the radiation issues in an easy-to-understand manner.

In the previous article, overview of the Landfill Facility for the Specified Waste, as well as kinds of waste to be disposed of and treatment procedures of waste in the Former Fukushima Eco-tech Clean Center, one of the 2 Landfill Facilities for the Specified Waste.

In this article, as a subsequent work, specific methods for landfill of the Specified Waste, as well as treatment procedures of leachate in the Former Fukushima Eco-tech Clean Center will be elaborated.

In other words, this article responds to the following questions:

– How is waste specifically landfilled in the Former Fukushima Eco-tech Clean Center?
– How is leachate treated in the Former Fukushima Eco-tech Clean Center?

Table of contents of this article

I have been involved with the radiation-relevant issues, like the policy on the decontamination activities and the management of the Interim Storage Facility, after the accident of the Fukushima Daiichi Nuclear Power Plant in 2011.

I received a doctorate in the field of radiation, while working in Fukushima.

(Specific methods for landfill are elaborated) What is the Landfill Facility for the Specified Waste? (Vol. 2)

This article especially focuses on the Former Fukushima Eco-tech Clean Center, one of the 2 Landfill Facilities for the Specified Waste, and elaborates specific landfill methods, as well as methods for treatment of leachate.

Landfill methods of the waste in the Former Fukushima Eco-tech Clean Center

The Former Fukushima Eco-tech Clean Center (December, 2018)

First of all, as explained in this article, in the Former Fukushima Eco-tech Clean Center, both of the waste solidified by cement, and the waste which is not solidified by cement, are landfilled, but as represented in the above picture, the former is landfilled in the upper part, and the later is separately landfilled in the lower part of the landfill site.

The specific landfill methods are depicted in the above figure.

Taking advantage of characteristic of radioactive cesium, that it is likely to be adsorbed to soil particle, first, impermeable soil layer is laid on the existing waste since before the disaster in 2011, to adsorb radioactive cesium to the soil, even if the radioactive cesium is leaked out of the containers (a).

And the Specified Waste is landfilled by being piled up in a couple of layers on the impermeable soil layer.

The waste is not got out of the containers but instead landfilled by being sealed in the containers, to prevent leakage of the waste (b).

After the waste is piled up in a couple of layers, impermeable soil layer is laid on the waste again, and the procedures will be repeated, that a couple of layers of the waste and impermeable soil layer are laid alternately (c).

And in the areas, where landfill operation is not carried out, the surface is always temporarily covered with capping sheets, to reduce volume of rainfall, which comes into the landfill site and contacts with the landfilled waste, that leads to reduction of resulting leachate treated in the leachate treatment facility (d).

Moreover, gas ventilation pipes are equipped in the landfill site, to prevent flammable gas, which is generated due to fermentation of organic matters contained in the landfilled waste, from accumulating within the landfill site, and to exhaust the gas into atmosphere (e).

In addition, double-layer impermeable sheets are laid on the whole areas of the landfill site, to prevent leakage of the leachate out of the landfill site.

Lastly, the impermeable soil layers have slope, and even if rainfall comes into the landfill site, it will be drained out of the landfill site as quickly as possible (f).

Treatment methods of the leachate in the Former Fukushima Eco-tech Clean Center

Then, how is the leachate generated in the landfill site treated?

First, leachate drained from the landfill site is sent to the leachate balancing tank (a), further sent to the leachate treatment facility (b).

In this facility, organic matters and heavy metals are removed through coagulation, sedimentation and filtration procedures (c).

Water treated in the leachate treatment facility is temporarily stored in the treated water balancing tank (d).

With regard to the water in the treated water balancing tank, its radioactivity concentration is monitored (e), and it is released into the environment (f), after it is confirmed, that it is below the criterion.

In the unlikely event, that the radioactivity concentration in the treated water is above the criterion, radioactive materials are adsorbed in the zeolite adsorption tower (g).

After that, it is released into the environment (h), after it is confirmed that it is comply with the criterion.

Reprun Fukushima

You can learn the detailed information about the landfill project of the Specified Waste, as well as safety measures on-site, in the Reprun Fukushima, which is located in the vicinity of the Former Fukushima Eco-tech Clean Center, and started its operation in August 2018.

Please visit the information center at your convenience.

Summary

This article covers specific landfill methods of the waste, as well as treatment methods of leachate, in the Former Fukushima Eco-tech Clean Center, one of the 2 Landfill Facilities for the Specified Waste.

And as last, the Reprun Fukushima was just briefly introduced, the information center of the landfill project for the Specified Waste.

By the way, above-mentioned contents are summarized in the following videos.

It would be appreciated to visit them at your convenience.

– Japanese version

– English version

You can read the same article in Japanese here.

Thank you very much for reading this article.

See you next time!