Development of nondestructive measurement technique in -waste including neptunium

Kurosawa, Makoto ; Ouchi, Shoichi*; Abe, Jiro; Okane, Shogo; Usui, Takeshi

Method for measurement of plutonium in -waste using passive ray has been adopted at Plutonium Fuel Research Facility. Recently, research of neptunium has been started. It is necessary to evaluate the passive ray method for measurement of plutonium in -waste including plutonium and neptunium together. This report describes the results of comparing the two methods, deduction method and division method. The error of deduction method is about 10 to 15% when the quantity of plutonium is larger than 100 mg in the waste. But the error reaches more than 50% when the quantity of plutonium is less than 10 mg and the ratio of plutonium and neptunium is less than one. On the other hand, the error of division method is about a few to 15% when the quantity of plutonium is larger than 100 mg in the waste. The error is about 30 to 50% when the quantity of plutonium is less than 10 mg, but the error is not affected by the ratio of plutonium and neptunium. By reason of this results, the division method is adopted for measurement of plutonium in -waste including neptunium.