Safety Measures Implementation at Kashiwazaki-Kariwa Nuclear Power Station
Thorough Implementation of Measures against Tsunami at Kashiwazaki-Kariwa Nuclear Power Station
| 1. Measures to prevent flooding of the power station site | Seawalls built along the sea side (at 15m above sea level) |
| 2. Measures to prevent flooding of the buildings | Flood barrier walls and flood barrier panels installed to protect the Reactor Building, etc. |
| Replace the outside doors with watertight doors | |
| Cover the penetration areas such as pipes | |
| 3. Measures to prevent flooding of the critical equipment rooms | Replace the inside doors (of the critical equipment rooms) with watertight doors |
At Kashiwazaki-Kariwa Nuclear Power Station, measures against Tsunami are thoroughly implemented to ensure safety even in the case that an unexpectedly large Tsunami hits.
1. Measures to Prevent Flooding of the Power Station Site (Seawalls)
Unit 1-4 seawalls
1,000m-long reinforced concrete seawalls with a robust foundation structure which can withstand Tsunamis and earthquakes are to be built at 15m above sea level. The south end of the retaining wall will be connected to the high ground with cement improved soil for improved robustness. The seawalls will also be equipped with a function to drain water that flows into the site.
Unit 5-7 seawalls
1,000m-long cement improved soil seawalls with robustness which can withstand Tsunamis and earthquakes are to be built at 15m above sea level. The seawalls will be connected with the high ground on the both sides of the station for improved robustness. The seawalls will also be equipped with a function to drain water that flows into the site.
2. Measures to Prevent Flooding of the Buildings
Even in the case that an unexpectedly large Tsunami hits and the power station is flooded up to 15m above sea level, flooding of the buildings can be prevented by the flood barrier walls and flood barrier panels installed on the outer wall openings such as vent holes. (The flood barrier walls/panels are installed for Unit 1-4 as there are openings at locations at 15m above sea level and below.)
3. Measures to Prevent Flooding of the Critical Equipment Rooms
The doors to the critical equipment rooms are replaced with watertight doors to prevent the critical equipments to be exposed to seawater in case seawater flows into the building.
Watertight doors for the critical equipment rooms
(Example: Unit 1 Reactor Core Isolation Cooling System pump room)
