04.02.2013 Views

Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course in Korea

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

❙ 343 ❙<br />

5. SITING CONSIDERATIONS<br />

5.5. EVALUATION OF THE REGIONAL IMPACT OF<br />

THE PLANT IN THE SURROUNDING REGION<br />

5.5.1. Atmospheric dispersion of radioactive substances<br />

5.5.1.1. General<br />

Forecast studies of the radiological consequences of rout<strong>in</strong>e discharges and accidental<br />

discharges are a factor <strong>in</strong> site selection, plant design, and emergency plann<strong>in</strong>g. They<br />

require data representative of the weather conditions at the site (w<strong>in</strong>d speed and direction,<br />

ra<strong>in</strong> atmospheric stability). These data are needed for the use of atmospheric dispersion<br />

models.<br />

In order to evaluate consequences after accidental releases, a set of dedicated computer<br />

tools has been developed. This consists of coherent tools, adapted to the different phases<br />

of an accident (anticipation phase and release phase) and at all appropriate scales (local to<br />

transborder).<br />

This follow<strong>in</strong>g part of the document successively describes the atmospheric dispersion<br />

model and calculation of deposits (with and without ra<strong>in</strong>) and depletion of the plume<br />

(used <strong>in</strong> the “CONRAD” French system).<br />

5.5.1.2. Atmospheric dispersion model<br />

The calculation codes are based on the solution of a partial differential equation (of<br />

“advection‐diffusion”). They differ from one another <strong>in</strong> treat<strong>in</strong>g the source either as a<br />

sequence of brief successive emissions called "puffs" or as a cont<strong>in</strong>uous emission called a

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!