Cambridge Environmental Research Consultants (CERC)

ADMS 5 Buildings Validation EOCR Study

1 Introduction

The Experimental Organically Cooled Reactor (EOCR) study1 (Start et al. [1]) involved the simultaneous release of three tracer gases (SF6- F12, and Freon-12B2) at three levels around the EOCR test reactor building at the Idaho National Engineering Laboratory in southeast Idaho, USA.

The terrain was flat with low-lying shrubs. The main building was 25 m high with an effective width of 25 m.

The tracer releases typically occurred simultaneously and were conducted during 22 separate time periods. Tracer sampler coverage was provided at eight concentric rings at distances of about 50. 100. 200, 400, 800, 1200, and 1600 m from the release points (see Figure 1).

Most of the meteorological data were measured on site and conditions were mainly unstable.
The input data for the ADMS rims were taken from the AERMOD files downloaded from the United States Environmental Protection Agency website [3].

These data included the arcwise maximum observed concentrations that have been used for comparison with the ADMS modelled concentrations. There were data for only 19 time periods and no data for the concentric ring distance of 200 m.

This document compares the results of ADMS (hereafter referred to as ADMS 5.0) with those of ADMS (hereafter referred to as ADMS 4.2).