NESC9668 UCBNE10.4.

1. NAME OR DESIGNATION OF PROGRAM:  UCBNE10.4.

3. DESCRIPTION OF PROGRAM OR FUNCTION

UCBNE10.4 calculates the one- dimensional time-dependent migration of radionuclides in a three- member chain in a geological medium saturated with ground water. The geological medium is considered to be a composite material, which consists of solid and liquid phases, and the transport of radionuclides along the interface between the two phases is neglected.
The various possible release modes which can be considered include the step, band, exponential, and preferential release modes  with either a plane source or concentration boundary condition. Variable input parameters include ground-water velocity, dispersion  coefficient, lead time, and the individual half life, retardation coefficient, and initial inventory for each chain member. Radioactive waste is viewed as consisting of radionuclides dispersed through a solid matrix. A finite dissolution rate of the waste material results in a band release of radionuclides into the ground  water; it is assumed that all of the waste material begins to dissolve at time, t=0, and dissolution is complete with a leach time, T. When the band-release time T approaches infinity, the release mode becomes a step release; it is assumed that the waste material dissolves at a finite rate over an infinite period. On physical grounds, waste material may reasonably be expected to dissolve at an infinitesimal rate in the case of a step release. The preferential release mode assumes that each radionuclide leaches from the waste at a constant fractional rate which is nuclide- dependent. If all species dissolve at the same fractional rate, (i.e. all have the same fractional rate constant), this becomes the  exponential release mode.
Either of two forms of output may be selected. The first produces normalized nuclide and radioactivity concentrations; the second generates radioactivity and ingestion hazard discharge rates.

4. METHOD OF SOLUTION

The program calculates the advective and disperse transport of radionuclides perpendicular to a plane boundary in a semi-infinite medium which is initially void of radionuclides. Water flow and all nuclide movement is perpendicular  to the plane boundary. Transverse dispersion is neglected. A rational approximation is used to evaluate the function e**(x**2)erfc(x), and an infinite series approximation is used for the complex error function.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM:

6. TYPICAL RUNNING TIME

The sample problem requires 1.19 CPU seconds  to execute on a DEC VAX8650.

7. UNUSUAL FEATURES OF THE PROGRAM:

8. RELATED AND AUXILIARY PROGRAMS:

10. REFERENCES

- W.B. Light, P.L. Chambre, W.W.-L. Lee, and T.H. Pigford:
  An Updated Computer Code for Radionuclide Chain Migration:
  UCB-NE-10.4, Transactions of the American Nuclear Society,
  Vol. 62, pp. 95-96 (November 11-15, 1990).
- Michael J. Moen and George Jansen, Jr.:
  The Pulse Release Mode for Calculation of Radionuclide Chain
  Migration
  Transactions of the American Nuclear Society, Vol. 62, pp.
  301-303, (November 11-15, 1990).
- C. Yuelys-Miksis:
  UCBNE10.4, NESC No. 9668, UCBNE10.4 Tape Description and
  Implementation Information
  NESC Note 91-55 (March 4, 1991).

- W.B. Light:
  UCB-NE-10.4 User's Manual
  UCB-NE-4133 (1990).
_ M. Harada et al.:
  Migration of Radionuclides Through Sorbing Media Analytical
  Solutions - I
  ONWI-359, LBL-10500 (February 1980).

11. MACHINE REQUIREMENTS:

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:  ULTRIX and VMS.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHORS

T.H. Pigford and W.B. Light
Department of Nuclear Engineering
University of California, Berkeley

File name	File description	Records
NESC9668_02.001	Information file	35
NESC9668_02.002	UCBNE10.4 source program (Fortran-77)	725
NESC9668_02.003	UCBNE10.4 test case input data	10
NESC9668_02.004	UCBNE10.4 test case printed output	314