Jul 13 (NHK) - The operator of the crippled Fukushima Daiichi nuclear power plant has proposed a way to determine the safety of treated water that is to be released into the ocean.
The Japanese government in April decided on a plan to begin the discharge in about two years. The water will be diluted to lower the concentration of radioactive materials, such as tritium, to levels below national standards.
Tokyo Electric Power Company made the proposal at a meeting of the Nuclear Regulation Authority on Monday.
The company proposed that it will use levels of tritium concentration before the water is diluted and the amount of seawater to be mixed to determine if tritium levels meet the requirements.
It says measuring tritium in diluted water takes too much time because of the material's behavior.
The utility says up to 500 cubic meters of treated water will be released per day. It says it will provide three large pumps to take in seawater and that treated water and seawater will be fed and mixed in a pipe about two meters in diameter.
A calculation by TEPCO estimates the ratio of treated water to seawater is one to over 340 when one pump is used.
At the meeting, some academics requested that the company periodically release the actual measurements of tritium concentration in diluted water. Others argued that accurate testing of the dilution is needed.
The utility says it will take into account what has been discussed at the meeting and decide on a specific equipment configuration. It will then seek the nuclear authority's approval of the plan.
Source: ANNnewsCH
