The new meteorological tower at the Leningrad II NPP will collect data from a height ten times higher than the standard.
Construction of the automatic meteorological station for continuous monitoring of environmental parameters has begun with the pouring of first concrete into the foundation of the 43-metre mast.
“The weather station is equipped with sensors that can receive data from a height almost ten times higher than the standard - up to 300 metres," said Vyacheslav Evgeniev, deputy chief engineer at the Leningrad II NPP for nuclear safety and security. “In the event of an emergency, this will allow us to more accurately predict the radiation situation in the observation area of ??the nuclear power plant, to simulate the spread of hypothetical pollution in the atmosphere, on the surfaces of the earth and water, and to make accurate decisions on protecting personnel and the public.”
Data on wind speed and direction, air temperature, humidity, atmospheric pressure and precipitation will be transmitted continuously via secure communication channels - cable and radio channels - to the database of the automated system for monitoring the radiation situation (ASKRO) in the city of Sosnovy Bor and at the industrial Leningrad NPP site.
The new weather station will be able to perform self-diagnostics and transmit information about failures or unauthorised opening of equipment to the central control centre of ASKRO.
In case of loss of power supply, the weather station will independently connect to the backup source and continue to work.
The station will be commissioned this spring - before the physical launch of Leningrad II-2. Start-up is scheduled for April 2020.
ASKRO at the Leningrad plant is one of the most extensive radiation monitoring systems in Russia. It has been working for over 20 years and includes 21 observation posts. These posts are located in the power plant exclusion zone, the 17km observation zone, as well as outside it.
Meanwhile, at Leningrad II-2, tests have been conducted on the inner protective shell of the reactor building designed to prevent the release of radioactive substances into the environment.
Specialists tested the shell with vacuum and overpressure. The results confirmed that the shell of the reactor building is durable, airtight and able to withstand design and emergency thermal, chemical and mechanical stresses.
“Tests have confirmed that the inner protective shell of reinforced concrete 1.2 metres thick and the lining of carbon steel are of high quality with no defects, cracks, or deformations. During operation, the shell will eliminate radiation leakage outside the reactor building in all operating modes, including in emergencies, and will ensure the safety of NPP personnel, the public and the environment,” explained chief engineer Alexander Belyaev.
In addition to the inner containment, Generation 3+ VVER-1200 units have an outer containment to protect the reactor, steam generators and other equipment from extreme external influences such as hurricanes, explosions, earthquakes, shock waves, aircraft crashes, etc.
On 12 March, at Leningrad II-2, complex tests on a block diesel generator. In the event of an emergency, this 6.3MW installation will supply power to the unit to put it into a safe condition.
“Now we are testing the diesel generator at different power levels and the operation including the complete de-energisation of the auxiliary sections of the reliable power supply systems,” said Aleksey Shlenkin, deputy head of the electrical department.
All five diesel generators are equipped with autonomous systems of fuel, cooling, lubrication, starting air, heating, ventilation, and auxiliary power supply. To ensure reliable start-up, each EDG is equipped with a backup start-up circuit, which is carried out by a signal from the control safety systems. In case of disconnection of the external power source, they will provide power to all the main technological systems of the unit.