Another HLW Leak
Japan Nuclear Fuel Ltd. (JNFL) is currently trying to restore the Rokkasho Reprocessing Plant after a leak of about 150 liters of high-level radioactive liquid waste (HLW) in the vitrification facility in January 2009 (NIT 129, 130, 131, 132). However, just before midnight on October 21 another leak occurred from the same pipe. The leak occurred because a chain hanging from a crane knocked against the flange. Fortunately, this time when the problem was identified only about 20 ml had leaked into the tray below.
JNFL finally admitted that the leak was HLW on October 29, one week after the incident. Based on the concentration of cesium-137 there were never any grounds for doubt, but JNFL continued to say that it did not know whether or not it was HLW, because HLW was not being fed into the pipe at the time. However, it eventually discovered that there was 510 ml of HLW remaining in the pipe. JNFL has given no explanation of why the HLW was there.
LLW dumped in spent fuel storage building
The spent fuel storage pool at Rokkasho began operation in December 1999. It has a total storage capacity of 3,000 tons and is now nearly full with 2,800 tons of spent fuel.
On September 7 it was revealed that a large quantity of plastic bags containing low-level radioactive waste (LLW) were strewn all around the building. By rights this waste should not be there at all, but as it is it has been left all over the place on the floor and in passageways (see photos below).
LLW, including paper, rags and polyethylene, rubber gloves, vinyl chloride and resins, steel and concrete, filters, etc., is produced during daily checks and annual inspections of the spent fuel storage building. This is supposed to be stored in LLW Storage Building No. 1. However, as a result of work to rectify numerous problems that have occurred over the past several years, large quantities of "unscheduled waste" were produced. The problems included leaks due to shoddy welding of the pool liner (2002-2004, NIT 88 (pdf only), 95, 98), leaks in the burnable poisons treatment pit (2005, NIT 107) and earthquake safety design flaws for spent fuel handling equipment (2007, NIT 118).
JNFL increased the quantity of waste drums that could be contained within the waste storage building from 8,500 to 13,500, but this was still not enough. JNFL says that there are currently 13,332 drums stored in the building and that the excess is being stored temporarily in the spent fuel storage building. It estimates that the quantity temporarily stored in this way would fill 8,100 drums, but does not know the precise number.
"Temporary storage" commenced some time between July and September 2001. In September of that year government inspectors told JNFL that if it must store the waste temporarily then it should do it properly. JNFL produced a temporary storage manual and since then temporary storage has become routine practice. JNFL's waste "contaminated by spent fuel" has been left in passageways, on the floor, on scaffolding and on steel pallets throughout the spent fuel storage building. JNFL may prefer to refer to it euphemistically as waste "contaminated by spent fuel", but the fact is that it is radioactive waste. Storage in this fashion is clearly a violation of the Reactor Regulation Law. JNFL says that the situation will be rectified during 2010.
Masako Sawai (CNIC)
Return to NIT 133 contents
See previous articles about he active testing of the Rokkasho Reprocessing Plant.