{"id":1687,"date":"2016-09-20T08:41:39","date_gmt":"2016-09-19T23:41:39","guid":{"rendered":"https:\/\/fdada.info\/?page_id=1687"},"modified":"2017-01-06T17:21:13","modified_gmt":"2017-01-06T08:21:13","slug":"obj_1-en","status":"publish","type":"page","link":"https:\/\/fdada.info\/fdada\/en\/home2\/decommissioning2\/obj_00-en\/obj_1-en\/","title":{"rendered":"<!--e02-02-01-->Maintaining and management of stable condition of fuel debris retrieval"},"content":{"rendered":"<!-- category=ObjIndex lang=ja -->\n<div id=\"container\">\n<h1>Maintaining and management of stable condition of fuel debris retrieval<\/h1>\n<p style=\"text-indent:1em\">\nThe current conditions of Units 1-3 can be estimated to maintain the stable cold shutdown state based on <a href=\"..\/..\/..\/obj_appendix_4_2-en\/\"> the\nplant data of the inside of the PCV, such as the temperature, hydrogen concentration and pressure recorded\nsince the accident<\/a>. <\/br>\n<p style=\"text-indent:1em\">\nMoreover, technical developments required for practical application of the fuel debris retrieval methods,\nsuch as the development of equipment and facilities for remote decontamination, investigation, and work are\nbeing advanced. It is, therefore, important to maintain, control and monitor the condition of plant, fuel debris\nand FP such as Cs in ensuring safety until fuel debris retrieval starts.<\/br>\n<p style=\"text-indent:1em\">\nAlthough at this moment, it is difficult to observe the condition of fuel debris directly due to high radiation,\nthe information is required to be understood from the perspective of maintaining and management of safety\nstate. The status of the information obtained to date is as follows:<\/br>\n<h2><a href=\".\/obj_1_1-en\"><span style=\"color: blue;\" color=\"white\">\u2460Criticality control<\/span><\/a><\/h2>\n<p>Although it is assumed that the fuel debris is in a stable condition at present, it cannot be denied that it\nmay become critical due to a certain cause, and so the criticality control is required.<\/p>\n<h2><a href=\".\/obj_1_2-en\"><span style=\"color: blue;\" color=\"white\">\u2461Cooling<\/span><\/a><\/h2>\n<p>Because fuel debris has decay heat and can release contained radioactive materials when it becomes a\nhigh temperature, so it needs to be cooled with water.<\/p>\n<h2><a href=\".\/obj_1_3-en\"><span style=\"color: blue;\" color=\"white\">\u2462Containment<\/span><\/a><\/h2>\n<p>Since release of fuel debris and FPs such as Cs to the outside has a significant impact on workers and\ngeneral public, it is required to be prevented by the PCV, etc. so that they may not be released to the\noutside.<\/p>\n<h2><a href=\".\/obj_1_4-en\"><span style=\"color: blue;\" color=\"white\">\u2463Maintenance\/reliability improvement of safety system<\/span><\/a><\/h2>\n<p>Maintenance and reliability improvement are required for the facilities necessary for maintaining the\ncurrent safe condition of fuel debris.<\/p>\n<p><a name=\"p1\" id=\"p1\"><\/a> <img decoding=\"async\" src=\"\/images\/en\/OBJ\/obj_1_fig01-en.jpg\" usemap=\"#map1\" \/> <map name=\"map1\"> \n      <area shape=\"rect\" coords=\"285,90,505,145\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\" alt=\"URL00\u3078\">\n      <area shape=\"rect\" coords=\"78,170,230,228\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_1-en\" alt=\"URL1\u3078\">\n      <area shape=\"rect\" coords=\"318,170,475,228\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_2-en\" alt=\"URL2\u3078\">\n      <area shape=\"rect\" coords=\"518,170,675,228\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_3-en\" alt=\"URL3\u3078\">\n\n      <area shape=\"rect\" coords=\"20,251,89,283\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_1-en\/obj_1_1-en\" alt=\"URL1.1\u3078\">\n      <area shape=\"rect\" coords=\"95,251,143,283\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_1-en\/obj_1_2-en\" alt=\"URL1.2\u3078\">\n      <area shape=\"rect\" coords=\"148,251,207,283\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_1-en\/obj_1_3-en\" alt=\"URL1.3\u3078\">\n      <area shape=\"rect\" coords=\"214,248,310,283\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_1-en\/obj_1_4-en\" alt=\"URL1.4\u3078\">\n\n      <area shape=\"rect\" coords=\"35,344,227,394\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_2-en\/obj_2_1-en\" alt=\"URL2.1\u3078\">\n      <area shape=\"rect\" coords=\"10,434,72,480\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_2-en\/obj_2_1-en\/obj_2_1_1-en\" alt=\"URL2.1.1\u3078\">\n      <area shape=\"rect\" coords=\"76,434,133,481\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_2-en\/obj_2_1-en\/obj_2_1_2-en\" alt=\"URL2.1.2\u3078\">\n      <area shape=\"rect\" coords=\"136,432,202,481\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_2-en\/obj_2_1-en\/obj_2_1_3-en\" alt=\"URL2.1.3\u3078\">\n\n      <area shape=\"rect\" coords=\"480,250,695,282\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_3-en\/obj_3_1-en\" alt=\"URL3.1\u3078\">\n      <area shape=\"rect\" coords=\"708,250,801,282\" href=\"\/en\/home2\/decommissioning2\/obj_00-en\/obj_3-en\/obj_3_2-en\" alt=\"URL3.2\u3078\">\n <\/map><\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"Maintaining and management of stable condition of fuel debris retrieval The current conditions of Units 1-3 ca [&hellip;]","protected":false},"author":1,"featured_media":0,"parent":1680,"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-1687","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1687","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=1687"}],"version-history":[{"count":1,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1687\/revisions"}],"predecessor-version":[{"id":2737,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1687\/revisions\/2737"}],"up":[{"embeddable":true,"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/pages\/1680"}],"wp:attachment":[{"href":"https:\/\/fdada.info\/fdada\/wp-json\/wp\/v2\/media?parent=1687"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}