DRSPALL: Impact of the Modification of the Numerical Spallings Model on Waste Isolation Pilot Plant Performance Assessment.

Technical Report · Thu Dec 31 23:00:00 EST 2015

DOI:https://doi.org/10.2172/1235212· OSTI ID:1235212

Kicker, Dwayne Curtis ^[1]; Herrick, Courtney G. ^[2]; Zeitler, Todd ^[2]; Malama, Bwalya ^[2]; Rudeen, David Keith ^[3]; Gilkey, Amy P. ^[3]

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1. Stoller Newport News Nuclear, Inc., Carlsbad, NM (United States)
2. Sandia National Lab. (SNL-NM), Carlsbad, NM (United States)
3. GRAM Inc., Albuquerque, NM (United States)

The numerical code DRSPALL (from direct release spallings) is written to calculate the volume of Waste Isolation Pilot Plant (WIPP) solid waste subject to material failure and transport to the surface as a result of a hypothetical future inadvertent drilling intrusion. An error in the implementation of the DRSPALL finite difference equations was discovered as documented in Software Problem Report (SPR) 13-001. The modifications to DRSPALL to correct the finite difference equations are detailed, and verification and validation testing has been completed for the modified DRSPALL code. The complementary cumulative distribution function (CCDF) of spallings releases obtained using the modified DRSPALL is higher compared to that found in previous WIPP performance assessment (PA) calculations. Compared to previous PAs, there was an increase in the number of vectors that result in a nonzero spallings volume, which generally translates to an increase in spallings releases. The overall mean CCDFs for total releases using the modified DRSPALL are virtually unchanged, thus the modification to DRSPALL did not impact WIPP PA calculation results.

• Research Organization: Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States); Sandia National Laboratories, Carlsbad, NM
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1235212
• Report Number(s): SAND2016-0231; 618361
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
97 MATHEMATICS AND COMPUTING
COMPARATIVE EVALUATIONS
CORRECTIONS
D CODES
DISTRIBUTION FUNCTIONS
DRILLING
EQUATIONS
ERRORS
FAILURES
FINITE DIFFERENCE METHOD
HUMAN INTRUSION
MATHEMATICAL MODELS
MODIFICATIONS
PERFORMANCE
RADIONUCLIDE MIGRATION
SOLID WASTES
VALIDATION
VERIFICATION
VOLUME
WIPP