RSICC CODE PACKAGE CCC-675

1. NAME AND TITLE

NUTRAN: Code System for Long-Term Repository Safety Analysis.

2. CONTRIBUTORS

Analytic Sciences Corp., Reading, Massachusetts, through the Energy Science and Technology Software Center, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV (50%) and PL/I (50%); IBM370 (C00675I037000).

4. NATURE OF PROBLEM SOLVED

NUTRAN is a system of four computer programs for calculating the dose to humans from radionuclides carried out of deep geologic nuclear waste repositories by ground water. NUTRAN is composed of the FORTRAN programs ORIGEN1 and BIODOSE and the PL/I programs WASTE and PLOT. ORIGEN1, developed by Oak Ridge National Laboratory, generates an inventory of radionuclides as a function of time; BIODOSE computes the doses to humans which result from any releases of radioactivity into the biosphere. WASTE models the release of radionuclides from a repository and their transport in the subsurface, and PLOT combines the results of BIODOSE and WASTE dose per MWe-yr released and releases in units of MWe-yr of waste to obtain doses and generate dose plots. The ORIGEN1 program developed by ORNL is not included. The NUTRAN model incorporates the following features: refilling of the repository cavity with water; leaching of the waste matrix; dissolution of the radioactive elements in the waste; transport of waste by ground water through the repository, surrounding strata, and adjacent aquifers; withdrawal of contaminated ground water through wells; transport of waste in surface waters and associated ecosystems; and human exposure and dose mechanisms.

5. METHOD OF SOLUTION

A three-dimensional ground water flow field is modeled as a network of one-dimensional flow paths or stream tubes. The stream tube approach allows a relatively straightforward representation of small discontinuities (e.g. faults, boreholes), avoiding the difficulties which are encountered in solving time-dependent solute migration problems by finite-element or finite-difference methods. For each stream tube, nuclide transport is solved explicitly by a green's function (impulse response) approach. The biosphere transport is modeled by a system of sediment, water, and soil compartments. Radionuclide concentrations in these compartments are used to compute doses to humans.

6. RESTRICTIONS OR LIMITATIONS

The ORIGEN1 program is not included in this distribution.

7. TYPICAL RUNNING TIME

The longest running sample problems required less than 9 CPU on an IBM 3090.

8. COMPUTER HARDWARE REQUIREMENTS

Minimum requirements are 1Mbyte (BIODOSE), 512K bytes (WASTE), 512K bytes (PLOT) on an IBM 370.

9. COMPUTER SOFTWARE REQUIREMENTS

NUTRAN ran under either OS/VS1 (IBM370) or MVS/XA (IBM3070) operating systems and required both Fortran IV and PL/I compilers.

10. REFERENCES

C.M. Koplik, J.Y. Nalbandian, and J.I. Scott, "User's Guide to NUTRAN: A Computer Program for Long-Term Repository Safety Analysis," TR-3854-5 (June 1983).

NESC9888 NUTRAN Sample Output.

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one diskette on which the source, datafiles, test case input and JCL are written in DOS format.

12. DATE OF ABSTRACT

July 1999.

KEYWORDS: HYDRODYNAMICS; INTERNAL DOSE; LIQUID PATHWAY; RADIONUCLIDES; WASTE MANAGEMENT