This document summarizes the specialists' report on the lack of reliability of the reactors at Chernobyl, citing that the lack of protective layers and other structural flaws in the reactor that could lead to radioactive contamination and accidents.
July 20, 1984
Captain A. E. Nikifiorov, Operative Plenipotentiary of Division I, Department 2 of the Sixth Service USSR KGB Administration for Moscow and Moscow Oblast, 'Information about an Interview with Trusted Individual "Zh. V.A."'
This document was made possible with support from Carnegie Corporation of New York (CCNY)
About an interview with trusted individual “Zh.V. A.”
On July 18th, 1984, an interview was held with trusted individual “Zh.V.A,” a highly qualified specialist in the area of atomic energy and an employee at the “Energy” V.N.I.I.A.E.S. [All-Russian Scientific Research Institute for the Use of Atomic Energy Stations] NGO.
He communicated that at the Chernobyl and Kursk atomic energy stations there have been cases of pipeline breaches in the place where the zirconium cover joins with the steel pipes, or the steel-zirconium adapter, as it is called. It occurs in the following way: the zirconium cover is placed in a steel pipe, in which special mushroom-shaped depressions are made, and the steel pipe is compressed at a temperature of 900° C. As a result of the pressure and temperature, the diffused zirconium fuses with the steel at a thickness of several microns. The breach occurs in the lower part of the joint, since it is technologically impossible to reach the lack of a small, but nonetheless present, gap between the steel and zirconium in this part of the joint. Since steel and zirconium expand at different rates during use, an increase in the gap occurs, into which corrosion particles and impurities from the water enter, causing further damage. Earlier it was thought that this damage occurs because of an incorrect ratio of titanium to carbon, which should be no less than 5, but the most recent accidents demonstrate that even with a ratio of 8 these gaps occur.
As far as the trusted individual is aware, such problems were not observed at the Leningrad atomic energy station, since bushing is stretched over the joints that heats up first and additionally pulls the steel-zirconium adapter together when it cools. However, it is technologically difficult for the metallurgical factory in the city of Glazove, in the Udmurt ASSR to produce joints like the ones at the Leningrad atomic energy station, because the quantity of such joints that is needed is large, and the time needed to produce them is increasing. The factory will not be able to fulfill the output plan it was given for steel-zirconium joints in accordance with the plan for launching the RBMK type reactor.
“Zh.V.A.” communicated that such failures are observed in the first and second blocks of the Chernobyl atomic energy station and block II of the Kursk atomic energy station. There are no such failures in block I of the Kursk atomic energy station because this reactor is the first of its type and all of its joints have been thoroughly checked. At the present time the steel-zirconium adapters have been placed online and their quality control, in the opinion of our trusted individual, is weak. To fully abandon the use of such adapters is unthinkable, but it is necessary to better develop the technology of their manufacture, and this, “Zh.V.A.” says, is realistic.
In connection with this defect in the R.B.M.K. another problem arises, which is the search for all damaged joints, since there are around 1,700 pieces within the reactors and they are situated in the lower part of the reactor, the most dangerous area in terms of radioactivity. For now, it is possible to determine whether a damaged adapter is present from the appearance of a wet spot in the reactor’s graphite moderator. This spot encompasses several adapters and it is difficult to find the damaged one from among them. For this reason, there are times when undamaged adapters are also currently being removed. Work is being conducted in this direction, but so far there are no positive results.
On the whole, according to the opinion of our trusted individual, reactors of such a type still need to be manufactured, since there is not enough power in the country for the production of tank reactors.
Operative Plenipotentiary of Division I, Department 2 of the Sixth Service USSR KGB Administration for Moscow and Moscow Oblast
Captain A. E. Nikifiorov
The document refers to a conversation with a specialist in nuclear energy, who explains how gaps at the joints of pipes are causing problems in the blocks at both the Chernobyl and Kursk plants.
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