目　　次

■ 海外事情
フランス原子力情勢とフランス人に関する「超」私的考察 (3)
石黒修司

■ 報　　告
東海発電所の廃止措置における残存放射能量評価−生体遮蔽体− (11)
徳原一実 / 高谷純一 / 白川正広 / 竹村守雄
東海発電所の廃止措置における残存放射能量評価−中性子束分布詳細解析− (17)
竹村守雄 / 中尾　誠 / 高谷純一 / 徳原一実
海水ウラン吸着床係留設備の概念設計 (25)
土井禎浩 / 五十嵐実 / 椎野泰生 / 魚谷正樹

■ 紹　　介
新型転換炉ふげん発電所アイソレーション管理支援システム (30)
磯村和利 / 菅谷篤志 / 蓮沼潤一 / 小松利彰
原子力緊急時防災支援設備 (36)
神谷栄世 / 射場浩史 / 高木俊博/ 山田　正

■ グループ情報
FAPIGの機構 (44)

表紙デザイン：堀内秀和

CONTENTS

■ Overseas Information
“Super”Personal Views on the Status of Nuclear Industry
in France and French People (3)
S. Ishiguro

■ Report
Evaluation on Radioactivity for Decommissioning of Tokai Power Staition
−Biological Shield− (11)
K. Tokuhara / J. Takaya / M. Shirakawa / M. Takemura
Evaluation on Radioactivity for Decommissioning of Tokai Power Station
−Detail Analysis of Neutron Flux Distribution− (17)
M. Takemura / M. Nakao / J. Takaya / K. Tokuhara
Study on Mooring System for Fibrous Absorbent to Recover Uranium from Seawater (25)
Y. Doi / M. Igarashi / Y. Shiino / M. Uotani

■ Introduction
Isolation Management Support System in Advanced Thermal Reactor FUGEN (30)
K. Isomura / A. Sugaya / J. Hasunuma / T. Komatsu
Emergency Disaster Prevention Support Systems for Nuclear Power Facilities (36)
E. Kamiya / H. Iba / T. Takagi / T. Yamada

Cover Design：Hidekazu Horiuchi

SYNOPSES

Kazumi Tokuhara, Junichi Takaya, Masahiro Shirakawa, Morio Takemura
Evaluation on Radioactivity for Decommissioning of Tokai Power Staition
−Biological Shield−
FAPIG No. 160 pp.11〜16 (2002)

Tokai Power Station of JAPC (the Japan Atomic Power Company),that is the first commercial nuclear power plant in Japan, ceased commercial operation at the end of March 1998, and the decommissioning work of this plant has been started from December 2001. Evaluation of residual radioactivity of wastes produced in the process of dismantling is essential for the decommissioning plans, such as plans of dismantling, plans of treatment and disposal of radioactive waste, safety assessment, etc.. Therefore, for preparing specific decommissioning plans, it is important to evaluate residual radioactivity of structure precisely, such as core internals, reactor pressure vessel, biological shield, etc.. We were entrusted with the evaluation of residual radioactivity of Tokai Power Station by JAPC. Following is the result of this evaluation concerning biological shield. Radioactivity of structure is caused by activation reaction and secondary contamination, and in case of Tokai Power Station, it is mainly caused by the former. Radioactivity by neutron activation is calculated with use of verified data such as water content, material impurities, reactor output history, and so on, and compared with measured radioactivity at limited location. We have updated these data, and evaluated activation radioactivity of biological shield by using these qualified data. As a result, it was clarified that activation radioactivity of biological shield could be evaluated with good precision.

KEYWORDS：Tokai power station, biological shield, radioactivity, measurement, input data, decommissioning

Morio Takemura, Makoto Nakao, Junichi Takaya, Kazumi Tokuhara
Evaluation on Radioactivity for Decommissioning of Tokai Power Station
−Detail Analysis of Neutron Flux Distribution−
FAPIG No. 160 pp.17〜24 (2002)

The decommissioning work of Tokai Power Station of JAPC (the Japan Atomic Power Company), that is the first commercial reactor in Japan, has been started from December in 2001 after 33 years of operation. The evaluation of residual radioactivity and corresponding rank of burial disposal of the biological shield concrete is essential to prepare specific decommissioning plans and estimate decommissioning cost. An analysis system with use of the 3-dimensional discrete ordinates code TORT was organized to evaluate precise neutron distribution around the enormous area of duct enclosure where gas ducts of the primary cooling system are located between the primary and secondary shields. The neutron flux and radioactivity of the biological shields in the duct enclosure had been measured by JAPC to obtain their complicated distributions brought by neutron streaming through several large penetrations in the primary biological shield. Comparison between the calculated results and the accumulated measurement data showed good coincidence over several decades of distribution changes. It was concluded that we could evaluate precise neutron distribution essential to radioactivity evaluation by use of TORT analysis system.

KEYWORDS：Tokai power station, neutron distribution, radioactivity, decommissioning, biological shield, discrete ordinates code, TORT, neutron streaming

Yoshihiro Doi, Minoru Igarashi, Yasuo Shiino, Masaki Uotani
Study on Mooring System for Fibrous Absorbent to Recover Uranium from Seawater
FAPIG No. 160 pp.25〜29 (2002)

A development of fibrous amidoxime absorbent synthesized by radiation graftpolymerization is in progress to recover uranium from seawater. The absorbent are contained in metal cage and the numerous metal cages are dipped in seawater for a period. After the dipping, the cages are collected and the absorbents are treated chemically and the uranium from seawater is recovered. A mooring system with chain binding is designed to dip and collect the numerous metal cages in the ocean. The construction cost of the system is estimated. Thus, the technical problems in practical applications are extracted.

KEYWORDS：uranium recovery, seawater, mooring, chain binding, absorbent, construction cost

Kazutoshi Isomura, Atsushi Sugaya, Junichi Hasunuma, Toshiaki Komatsu
Isolation Management Support System in Advanced Thermal Reactor FUGEN
FAPIG No. 160 pp.30〜35 (2002)

The advanced thermal reactor is researched and driven at the Fugen Nuclear Power Station of Japan Nuclear Cycle Development Institute.
In 1984, the maintenance management system was developed by the online system on a mainframe computer for the prevention of human error and the efficiency improvement of the plant maintenance, and the function has been enhanced one by one (failure management, work management, isolation management support, and SWP/PWP management).
Moreover, this system was shifted to the present client-server system in 1999, and the improvement of user interface and the multimedia-compatible were performed.
In this thesis, we introduce the outline of the function which make and confirm the isolation, which is made with the isolation management support system, on the pipe and instrument diagram. The isolation management support system is the subsystem of the maintenance management system arranged in 2001 fiscal year.

KEYWORDS：nuclear power, isolation, CAD, plant maintenance, pipe and instrument diagram, prevention of human error

Eisei Kamiya, Hiroshi Iba, Toshihiro Takagi, Tadashi Yamada
Emergency Disaster Prevention Support Systems for Nuclear Power Facilities
FAPIG No. 160 pp.36〜p.43 (2002)

"Special Measures Law for Nuclear Disasters" was established in Japan in December 1999, and implementation of radiation monitoring in an emergency environment was specified in it.
Fuji Electric Co. has developed new systems and equipment for measurement of radiation in emergencies based on its conventional radiation measuring technology.
In this paper, we introduce, "mobile body surface contamination monitoring car" and "primary cell type personal dosimeter" of the newly developed systems and equipment.

KEYWORDS：body surface contamination monitor, personal dosimeter