Question : RADIATION LEAKAGE

(a) the total number of cases of radiation leakage reported at Atomic Power Stations in the country during the last three years; and

(b) the preventive measures taken by the Government to arrest such radiation leackages?

THE MINISTER OF STATE IN THE DEPARTMENT OF ATOMIC ENERGY (SMT. VASUNDHRA RAJE)

(a) & (b) A statement is laid on the Table of the House.

STATEMENT REFERRED TO IN REPLY TO LOK SABHA STARRED QUESTION NO.142 REGARDING RADIATION LEAKAGE BY SHRI T.M. SELVAGANPATHI FOR ANSWER ON 8.12.1999 -

(a) Some amount of radioactivity is permitted to be discharged from every Nuclear Power Plant (NPP). The Atomic Energy Regulatory Board (AERB) has specified the limits for the discharge of radio- activity for each of the NPPs.

In the last three years, there has been one incident e where this limit was exceeded. Subsequent to a leak in a moderator heat exchanger of RAPS Unit-2 on May 5, 1998, heavy water containing tritium activity got released into Rana Pratap Sagar Lake. Though the limit on the tritium discharge was exceeded, the annual radiation dose to the public due to this release was estimated to be less than 25 microsievert compared to the annual limit 1000 miccrosievert prescribed by AERB.

There was another incident, in MAPS Unit-2, of heavy water leak due to failure of seal plug during coolant channel inspection on March 26, 1999. This incident led to release of some radioactivity through the stack, which was well with in the specified limit. There was no release through the liquid route.

(b) Periodic inspection of equipment, prevention of leakages and careful control and monitoring of radioactive discha- rges are the preventive measures that continuously remain in force to ensure that rdioactive discharges/leakages do not exceed the limit laid down by AERB. That these measures are effective, is amply demonstrated by the fact that there has been only one event in the last three years (as described above) of exceeding the specified limit.