4.3　Sea Level Anomaly

4.3.1　For a coastal nuclear power plant，the effects of sea level anomaly on the design basis flood level shall be analyzed for the service life of the plant.

4.3.2　The representative tide observation stations selected for analyzing sea level anomaly shall not be exposed to effects of river runoff and human activities.And the tidal data obtained shall be analyzed for reliability and consistency.

4.3.3　The sea level change trend shall be analyzed after filtering the cyclical factors that may be contained in the monthly average sea level data.

4.3.4　The sea level change trend shall be determined based on the comprehensive analysis of results of related studies conducted in China.Based on the annual change rate thus obtained，the relative change range in the sea area neighboring the plant site shall be estimated for the design service life of the nuclear power plant.The sea level change and trend forecast can also be obtained from the announcement issued by national ocean authorities.