{"id":1621,"date":"2016-09-14T18:37:33","date_gmt":"2016-09-14T09:37:33","guid":{"rendered":"https:\/\/fdada.info\/?page_id=1621"},"modified":"2017-04-03T11:03:08","modified_gmt":"2017-04-03T02:03:08","slug":"decommissioning-13-en","status":"publish","type":"page","link":"https:\/\/fdada.info\/fdada\/en\/home2\/decommissioning2\/progress2\/decommissioning-13-en\/","title":{"rendered":"<!--e02-01-08-->Unit 2"},"content":{"rendered":"<!-- category=progress lang=en -->\r\n\r\n\r\n<div class=\"subnavi\">\r\n<ul>\r\n<li><a href=\"..\/decommissioning-15-en\">Summary of Decommissioning and Contaminated Water Management<\/a><\/li>\r\n<li><a href=\"..\/decommissioning-11-en\">Progress Status and Future Challenges of the Mid-and-Long-Term Roadmap<br \/>toward Decommissioning of TEPCO\u2019s Fukushima Daiichi Nuclear Power Station Units 1-4 (Outline)<\/a><\/li>\r\n<li><a href=\"..\/decommissioning-16-en\">Progress report<\/a><\/li>\r\n<li><a href=\"..\/decommissioning-8-en\">Status of seawater monitoring within and outside of the port<\/a><\/li>\r\n<li><a href=\"..\/decommissioning-4-en\">Progress toward decommissioning:Fuel removal from the spent fuel pool (SFP)<\/a><\/li>\r\n<li><a href=\"..\/decommissioning-5-en\">Progress toward decommissioning:Works to identify the plant status and toward fuel debris removal<\/a>\r\n<ul class=\"triangle\">\r\n<li class=\"sub\"><a href=\"..\/decommissioning-12-en\">Unit 1<\/a><\/li>\r\n<li class=\"sub active\"><a href=\"..\/decommissioning-13-en\">Unit 2<\/a><\/li>\r\n<li class=\"sub\"><a href=\"..\/decommissioning-14-en\">Unit 3<\/a><\/li>\r\n<\/ul>\r\n<\/li>\r\n<li><a href=\"..\/decommissioning-2-en\">Progress toward decommissioning:Work related to circulation cooling and accumulated water treatment line<\/a><\/li>\r\n<li><a href=\"..\/decommissioning-10-en\">Progress toward decommissioning:Work to improve the environment within the site<\/a><\/li>\r\n<\/ul>\r\n<\/div>\r\n<div id=\"article\" class=\"short_l\">\r\n<h1>Unit 2<\/h1>\r\n<h2>Status of Progress Points<\/h2>\r\n<p style=\"text-align: center;\"><img decoding=\"async\" src=\"\/images\/decommissioning\/unit2_01.png\" border=\"0\" alt=\"\" \/><\/p>\r\n<span style=\"font-size: 10px;\">&emsp;(*1) Penetration: Through-hole of the PCV<\/span><br \/>\r\n<span style=\"font-size: 10px;\">&emsp;(*2) SFP (Spent Fuel Pool)<\/span><br \/>\r\n<span style=\"font-size: 10px;\">&emsp;(*3) RPV (Reactor Pressure Vessel)<\/span><br \/>\r\n<span style=\"font-size: 10px;\">&emsp;(*4) PCV (Primary Containment Vessel)<\/span><br \/>\r\n<br \/>\r\n<br \/>\r\n<h3 class=\"ptitle\">Installation of an RPV thermometer and permanent PCV supervisory instrumentation<\/h3>\r\n<p style=\"float: right;\"><img decoding=\"async\" src=\"\/images\/decommissioning\/unit2_02.png\" border=\"0\" alt=\"\" \/><\/p>\r\n<p>(1) Replacement of the RPV thermometer<\/p>\r\n<ul class=\"list\">\r\n<li>As the thermometer installed at the Unit 2 RPV bottom after the earthquake had broken in February 2014, it was excluded from the monitoring thermometers.<\/li>\r\n<li>On April 17, 2014, removal of the broken thermometer failed and was suspended. Rust-stripping chemicals were injected and the broken thermometer was removed on January 2015.<\/li>\r\n<li>A new thermometer was reinstalled on March. The thermometer has been used as a part of permanent supervisory instrumentation since April.<\/li>\r\n<\/ul>\r\n<p>(2) Reinstallation of the PCV thermometer and water-level gauge<\/p>\r\n<ul class=\"list\">\r\n<li>Some of the permanent supervisory instrumentation for PCV could not be installed in the planned locations due to interference with existing grating (August 2013).<\/li>\r\n<li>The instrumentation was removed on May 2014 and new instruments were reinstalled on June 2014. The trend of added instrumentation will be monitored for approx. one month to evaluate its validity.<\/li>\r\n<li>The measurement during the installation confirmed that the water level inside the PCV was approx. 300mm from the bottom.<\/li>\r\n<\/ul>\r\n<br \/>\r\n<h3 class=\"ptitle\">Investigative results on torus room walls<\/h3>\r\n<p style=\"float: right; font-size: 16px;\"><img decoding=\"async\" src=\"\/images\/decommissioning\/unit2_03.png\" border=\"0\" alt=\"\" \/><br \/>Image of the torus room east-side cross-sectional investigation<\/p>\r\n<ul class=\"list\">\r\n<li>The torus room walls were investigated (on the north side of the east-side walls) using equipment specially developed for that purpose (a swimming robot and a floor traveling robot).<\/li>\r\n<li>At the east-side wall pipe penetrations (five points), \u201cthe status\u201d and \u201cexistence of flow\u201d were checked.<\/li>\r\n<li>A demonstration using the above two types of underwater wall investigative equipment showed how the equipment could check the status of penetration.<\/li>\r\n<li>Regarding Penetrations 1 - 5, the results of checking the sprayed tracer<sup> (*5) <\/sup>by camera showed no flow around the penetrations. (investigation by the swimming robot)<\/li>\r\n<li>Regarding Penetration 3, a sonar check showed no flow around the penetrations. (investigation by the floor traveling robot)<\/li>\r\n<p style=\"font-size: 10px;\">(*5) Tracer: Material used to trace the fluid flow. Clay particles<\/p>\r\n<\/ul>\r\n<br \/>\r\n<h3 class=\"ptitle\">Status of investigation inside the PCV<\/h3>\r\n<p>Prior to fuel debris removal, an investigation inside the PCV will be conducted to inspect the status there including the location of fuel debris.<\/p>\r\n<p>[Investigative outline]<\/p>\r\n<ul class=\"list\">\r\n<li>A robot, injected from Unit 2 X-6 penetration(*1), will access the inside of the pedestal using the CRD rail.<\/li>\r\n<\/ul>\r\n<p>[Progress status Status]<\/p>\r\n<ul class=\"list\">\r\n<li>As manufacturing of shields necessary for dose reduction around X-6 penetration was completed, a hole was made in December 2016 at the PCV penetration from which a robot will be injected.<\/li>\r\n<li>On January 26 and 30, 2017, a camera was inserted from the PCV penetration to inspect the status of the CRD replacement rail on which the robot will travel. On February 9, deposit on the access route of the selfpropelled investigation device was removed and on February 16, the inside of the PCV was investigated using the device.<\/li>\r\n<li>The results of this series of investigations confirmed fallen and deformed gratings and a quantity of deposit inside the pedestal. The evaluation results of the collected information will be utilized in considering the policy for fuel debris removal.<\/li>\r\n<p style=\"font-size: 10px;\">(*1) Penetration: Through-hole of the PCV\r\n<\/ul>\r\n<p style=\"text-align: center; font-size: 16px;\"><img decoding=\"async\" src=\"\/images\/decommissioning\/unit2_04.png\" border=\"0\" alt=\"\" \/><\/p>\r\n<p align=\"center\"><img decoding=\"async\" src=\"\/images\/decommissioning\/unit2_01_er.png\" border=\"0\" alt=\"\" \/><\/p>\r\n<br \/>\r\n<\/div>\r\n<!-- end.div article -->\r\n\r\n\r\n","protected":false},"excerpt":{"rendered":"Summary of Decommissioning and Contaminated Water Management Progress Status and Future Challenges of the Mid- [&hellip;]","protected":false},"author":1,"featured_media":0,"parent":1537,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"footnotes":""},"class_list":["post-1621","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1621","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/comments?post=1621"}],"version-history":[{"count":5,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1621\/revisions"}],"predecessor-version":[{"id":3520,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1621\/revisions\/3520"}],"up":[{"embeddable":true,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1537"}],"wp:attachment":[{"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/media?parent=1621"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}