OVERVIEW RECCOMENDATIONS FOR A SEISMIC RESPONSE PLAN FOR NUCLEAR POWER PLANTS

Abstract

Nuclear Power Plants (NPPs) are designed to resist seismic loading. As a part of the plant preparedness response, it would be prudent to have plans in place detailing processes and procedures to be followed should a seismic event occur. The absence of such plans can be detrimental to safety and would lead to costly assessments to continue (or resume operation in case the plant needed to be shutdown) after a seismic event.

The international guidance and the industry-accepted guidelines provide a framework to develop the needed plans. The scope of this guidance includes pre-earthquake planning and post- earthquake immediate, short term and long-term actions, along with criteria for both determination of design ground motion exceedance and need for reactor shutdown.

The seismic response plan should incorporate pre- and post-earthquake actions to monitor ground motion at the site, assess the level of shaking at various plant locations, decide when to shut down the plant if it were not already tripped, and inspection to evaluate any damage to a pre-selected set of safety related structures, systems, and components (SSCs). The specific actions and assessment to be prepared post-earthquake to formulate the safety case for the regulatory authority’s approval to restart and continue plant operation is one of the key parts of the pre-earthquake planning.