Filtered vent shown to media in Niigata

October 22, 2013

TEPCO shows Niigata plant's filtered vent to media

http://www3.nhk.or.jp/nhkworld/english/news/20131022_25.html

Tokyo Electric Power Company has shown a safety system called a filtered vent to the media at its Kashiwazaki-Kariwa nuclear power plant in Niigata Prefecture.

The system must be installed under tightened guidelines imposed earlier this year before the utility can restart operations. The guidelines are aimed at making nuclear power plants better equipped to deal with emergencies.

In September, TEPCO applied to the government nuclear regulator for the safety screening needed to restart the plant's Number 6 and 7 reactors.

Construction for the foundation of the vent system at the Number 7 reactor was completed last week, and installation work began on Tuesday.

Filtered vents are designed to curtail emissions of radioactive substances when reactors must undergo emergency venting to reduce pressure.

The cylinder vent is 8 meters high and 4 meters in diameter. It can cut the amount of radioactive substances released into the atmosphere by up to 0.1 percent, using a combined water and chemical filtration system.

Niigata Prefecture has told TEPCO that it will not allow the vents to be used until the utility hold talks with local governments about evacuation plans and the arrangements are approved.

The plant's safety center chief, Shiro Arai, says he wants to discuss emergency evacuation procedures with local governments, as some radioactive materials will be emitted even if the filters are used.

TEPCO plans to complete the work at the Number 7 reactor by the end of March next year. Work is under way to install the filtered vents at the plant's Numbers 1, 5 and 6 reactors.