1. NAME AND TITLE

ORION-II: A Computer Code to Estimate Environmental Concentration and Dose Due to Airborne Release of Radioactive Material

2. CONTRIBUTOR

Tokai Works, Power Reactor and Nuclear Fuel Development Corporation, Tokai-mura, Ibaraki-ken, Japan through the OECD NEA Data Bank, Gif-sur-Yvette, France.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; IBM 3090, FACOM M-780.

4. NATURE OF PROBLEM SOLVED

ORION-II was developed to estimate environmental concentration and dose due to airborne release of radioactive material from multiple sources of the nuclear fuel cycle facilities. ORION-II is an updated version of ORION and is applicable to the sensitivity study of dose assessment at nuclear fuel cycle facilities.

5. METHOD OF SOLUTION

The modified Gaussian plume model is applied to calculate atmospheric dispersion. The plume depletion models such as gravitational settling, dry deposition, precipitation scavenging and radioactive decay are considered as the causes of depletion and deposition on the ground and vegetation. Dose to an individual is calculated. Inhalation and oral intake are considered internal pathways, and submersion in the radioactive cloud and external exposure to ground surface contamination are external pathways.

6. RESTRICTIONS OR LIMITATIONS

The maximum number of nuclides is 30; number of release source is 10; number of food chains is 10.

7. TYPICAL RUNNING TIME

The sample problem was tested at NEADB on an IBM 3090; it took about 17 seconds of cpu time.

8. COMPUTER HARDWARE REQUIREMENTS

ORION-II runs on the IBM 3090 and FACOM M-780.

9. COMPUTER SOFTWARE REQUIREMENTS

The IBM VS Fortran Version 2 was used on the IBM 3090.

10. REFERENCE

T. Asano, K. Shinohara, O. Narita, "ORION-II: A Computer Code to Estimate Environmental Concentration and Dose Due to Airborne Release of Radioactive Material," PNCT N8410 87-17-Tr, (August 1987).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one (1.2MB) DOS diskette which contains the source code and sample problem.

12. DATE OF ABSTRACT

March 1991.