The PWR has 3 air-tight barriers to prevent any
radioactive leakage. The containment system, which includes such
features as the containment wall and containment penetration,
forms the third barrier to guard against radioactive leakage.
Containment penetration includes cable penetration, fluid tubing penetration and special penetration. A pressurized
system penetration
has already been used in
nuclear island design to check leakage. Such
containment
Framatome's
penetration design meets must be tightly sealed.
the requirement
that
the containment
Another point in the Report is "to ensure that the
nuclear island (reactor building) is SO constructed as to avoid
contamination of underground water
accident". Our views are as follows :
in case of a
severe
The Daya Bay nuclear power plant is built on a 6.5 metres of concrete raft. According to information of the plant
site, the nuclear plant will be
be located on
on bedrock. Even when
the reactor core melts down causing penetration of the concrete raft by molten fuel, only the water in the bedrock joints will be affected; but the water has no direct linkage with underground
water source. Therefore, core melt down incidents will not
contaminate underground water.
2. International Cooperation and Exchange
China joined the International Atomic Energy Agency (IAEA) in 1984, and has signed bilateral agreement with many countries on the peaceful use of nucear energy. In the past few years, China has always attached importance to participation in training courses and academic exchanges organized by the IAEA and