1. NAME AND TITLE

EMERALD: Calculation of Activity Releases and Potential Doses from a Pressurized Water Reactor Plant.

2. CONTRIBUTOR

Pacific Gas and Electric Company, San Francisco, California.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; IBM 360/370.

4. NATURE OF PROBLEM SOLVED

EMERALD is designed for the calculation of radiation releases and exposures resulting from normal and abnormal operation of a large pressurized water reactor. Because of the flexible nature of the simulation approach, EMERALD can be used for most calculations involving the production and release of radioactive materials including design, operational and licensing studies.

5. METHOD OF SOLUTION

The approach used in EMERALD is similar to an analog simulation of a real system. Each component or volume in the plant which contains a radioactive material is represented by a subroutine which keeps track of the production, transfer, decay, and absorption of radioactivity in that volume. During the course of the analysis of an accident, activity is transferred from subroutine to subroutine in the program as it would be transferred from place to place in the plant. For example, in the calculation of the doses resulting from a loss of coolant accident, the program first calculates the activity built up in the fuel before the accident, then releases some of this activity to the containment volume. The rates of transfer, leakage, production, cleanup, decay, and release are read in as input to the program. Subroutines are also included which calculate the on-site and off-site radiation exposures at various distances for individual isotopes and sums of isotopes. The program contains a library of physical data for the twenty-five isotopes of most interest in licensing calculations, and other isotopes can be added or substituted.

6. RESTRICTIONS OR LIMITATIONS

The user must limit his problem to: 25 isotopes, 7 time periods, 15 volumes or components, 10 distances.

The use of FORTRAN IV language, modular design, generic variable names, and extensive internal comments make EMERALD easily adapted to the users' particular models and problems.

7. TYPICAL RUNNING TIME

The packaged sample problem ran in 3.5 minutes on the IBM 360/75 computer.

8. COMPUTER HARDWARE REQUIREMENTS

EMERALD is operable on the IBM 360/370 computers. It uses 450 K of storage in the GO step.

9. COMPUTER SOFTWARE REQUIREMENTS

A FORTRAN IV compiler is required. OVERLAY is used.

10. REFERENCES

W. K. Brunot, "EMERALDA Program for Calculating Radiation Doses from a Pressurized Water Plant," Trans. Am. Nucl. Soc., 15-1, 550-551 (June 1972).

W. K. Brunot and D. V. Kelly, "EMERALD, A Program for the Calculation of Activity Releases and Potential Doses from a Pressurized Water Reactor Plant," Pacific Gas and Electric Company, Informal Report (October 1971).

11. CONTENTS OF CODE PACKAGE

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

12. DATE OF ABSTRACT

June 1973; updated July 1975.

KEYWORDS: ENVIRONMENTAL DOSE; AIRBORNE