For safety assessment of a reprocessing facility, it is important to know performance of radioactive materials in their accidental release and transfer. Accordingly, it is necessary to collect and prepare data for use in analyses for their performance.
At JAERI, it has been decided to investigate ANSI recommended American standard data together with their based experimental data by resorting to the original references and the relevant recent reports, in the hope that reasonable values for safety analysis parameters can be recommended by evaluating the investigated results.
For this objectives, JAERI has made a two-year contract with Nuclear Safety Research Association, to organize a working group under a Special Committee on Data Investigation for Reprocessing Facility Safety Assessment. This report summarizes the results obtained by the working group.

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For the development of a once-through unit type steam generator for an FBR, materials having a high mechanical strength at elevated temperatures and resistivity against stress corrosion cracking are needed for its heat transfer tubes. Although high-chrome steels meet these requirements, their durability under sodium-water reaction was not clear. The present experimental study was conducted to clarify this.
The experiment simulated the micro-leak and the small leak events under the accidental conditions. In the micro-leak experiment, a test section with an artificial hole was installed under sodium, and steam was ejected from the hole. A self-wastage rate was determined from the time required to leak hole enlargement. In the small leak experiment, steam was ejected from a hole of one tube toward a target tube. A wastage rate was determined from the time required to the penetration of the target tube.
The results reveal that the high-chrome steels have durability equivalent to or better than that of the steels currently being adopted for the heat transfer tubes of the steam generators. No appreciable difference was found among three high-chrome steels studied.

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The distribution coefficient of ⁶⁰Co, ⁸⁵Sr and ¹³⁷Cs for coastal sandy soil layer (aerated zone and aquifer zone) was determined. Effects of pH, conductivity and coexistent ions such as K⁺, Na⁺, Ma²⁺, Ca²⁺, Cl^-, HCO₃^- and SO₄^2- on the distribution coefficient were studied to clarify the correlation between the distribution coefficient and ion composition in ground water.
The sandy soil where sampling point is nearer to the sea, tended to lower the distribution coefficient of three radionuclides. The distribution coefficient of ⁸⁵Sr for the sandy soil of aquifer zone was markedly smaller than that of aerated zone. This was caused by the presence of Mg²⁺ and Ca²⁺ compositions in ground water. The distribution coefficient estimated on the basis of the effect of coexistent ion was sufficiently well agreed with the measured one. Therefore, the distribution coefficient in coastal sandy soil layer will be predicted from ion composition in ground water.

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In impact analysis for radioactive materials transport casks, it has become possible to perform them in detail by using finite element and finite difference computer codes, such as HONDO-II, DYNA2D, DYNA3D and PISCES. However, the considerable cost and computer execution time are necessary to perform analyses by these computer codes. Therefore, simplified computer codes which are capable of reducing cost and computer execution time are needed. To meet the above requirements, CRUSH code has been developed. CRUSH is a static calculation computer code capable evaluating the maximum acceleration of the cask body and the maximum displacement of the shock absorber.
Analytical results obtained by CRUSH code are compared with experimental results and the detailed computer code DYNA3D. Good agreements were obtained between simplified results and experimental and detailed analysis ones.

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