To build a nuclear power plant

it is a long time from pre-feasible studies to equipment design

manufacture and final installation.Taking second period construction program of Qinshan Nuclear Power Plant as an example

its ground motion parameters were determined 14 years ago.So

it should be checked based on the lasted seismic scientific data and technology

which include the methods to identify active tectonics

process inhomogeneity of seismic activity

divide seismic zone and belt

select the parameters for potential seismic source zone

and determine acceleration attenuation law.The conclusions about seismogeology and seismic activity in the report of seismic safety evaluation for Qinshan Nuclear Power Plant have been confirmed by new data.Earthquake activity in the region had no remarkable change.The average depth of the destructive earthquake occurred in the area is about 12 km

slightly less than 15 km in whole China.To integrate different standpoints

several different schemes were applied to evaluate seismic risk by statistical analysis of related acceleration attenuation laws.The safety limit of ground motion is 0.15 g

which is synthesized by several calculation schemes and agrees well with the former result made in"90 Report".The checking work in this paper sets a model for other similar works.