A facility for incinerating miscellaneous solid low-level waste has begun operating at the Japan’s damaged Fukushima Daiichi NPP. It is designed to burn solid wastes such as used personal protective equipment (including gloves and overalls), construction materials (rags, wood, packing materials, paper, etc), as well as waste oil and spent resins. The facility houses two incineration lines, each comprising a rotary kiln incineration system and a series of exhaust filters. The two lines share a common exhaust stack. Ash generated in the incinerators is stored in sealed drums for final disposal. Each incineration line has the capacity to process 300kg of waste per hour. The facility can operate 24 hours a day.
Construction of the facility, built by Kobelco, part of Kobe Steel Group, under contract from Tokyo Electric Power Company (Tepco), began in May 2013 and was completed last November. Cold testing of the facility – in which non-contaminated waste was burned – took place in November and December. This was followed by hot testing in February during which contaminated waste was incinerated.
Tepco said the facility is intended to reduce the volume of the radioactive waste "to one several tenth or less. "The waste materials can’t be taken off the site, so incinerating it and then storing the ash in sealed containers has been found to be the safest and most efficient way to reduce its volume." It noted that the facility was fitted with filters to prevent the dispersal of radioactivity in the air. "The amount of radioactive materials in the exhaust gas will be measured on a regular basis to prevent any impact on the surrounding environment," the company said.
Three existing low-level waste incinerators at the Fukushima Daiichi site, which could handle more than 8t of waste a day, are no longer in operation and are being used to store and process radioactive water.
Meanwhile, at least 3,100t of waste lacking proper registration is being stored throughout Japan, local media report, including radioactive waste produced in the cleanup of the Fukushima NPP, but local officials are reluctant to report it, according to Reuters. Tons of contaminated soil and other radioactive refuse are being stored at temporary depots, Japanese NHK TV-Channel reports. The level of radiation at the storage sites is above 8,000 Becquerels per kilogram, compared with the norm of 10 Becquerels per kilogram. NHK gathered the data by questioning local administrations of the Ibaraki, Iwate, Miyagi, Saitama, Chiba, Tokyo and Fukushima prefectures. The largest quantity of nuclear waste is said to be stored in the city of Kurihara in the Miyagi prefecture.
Local authorities are obliged by law to report to the government about the nuclear materials stored in their prefectures. However, they have not done so for five years, for the fear of negative publicity. If the waste is officially registered, local authorities will be told to build permanent storage facilities, which they fear may impact negatively on their regions.
Nuclear Regulation Authority Chairman Shunichi Tanaka has stressed the need to gain the understanding of local residents about the nuclear waste created by the 2011 Fukushima accident before any storage decision is taken. He says the waste may end up remaining at the plant’s compound for a long time. The Japanese government and Tepco say they will start removing the melted fuel from the plant’s three reactors in 2021. But future storage sites and final destinations have yet to be decided.
