DOE 2000. - Waste Isolation Pilot Plant - U.S. Department of Energy

WIPP RH PSAR DOE/WIPP-03-3174 CHAPTER 5
The crushing scenarios were modeled to produce rupture, or almost rupture in order to determine the
force required to produce a release. A force of 11,000 lbs on the shuttle car with a canister partially in
the road cask/shielded insert would be required to produce a bending that does not cause rupture in the
canister. This is much more than the force of approximately 2000 lbs required to move the shuttle car
between transfer positions. A second crushing scenario involved accidental closing of a shield valve on a
canister. Calculations show that 39 kips (almost 20 tons) of force must be exerted by a shield valve
closure in order to initiate a canister rupture. The force required to simply open and close the shield
valve is approximately 500 lbs. Passive and active engineered design features which prevent these
scenarios from occurring are described in section 5.2.3.3.
For the waste hoist accident scenario which involves a facility cask, containing a waste canister, drop of
over 2,000 ft (609.6 m), it is conservatively assumed that breach of the facility cask and waste canister
occurs resulting in a bounding DR of 0.25 for direct loaded waste and 0.025 for double confined waste.
Airborne Release (ARF) and Respirable (RF) Fractions
Based on the discussion in Section A.3.2 of Appendix A of DOE-STD-3009-94, 1 bounding values for the
ARFs and the RFs are utilized based on DOE-HDBK-3010-94. 4 The ARF for the burning of
contaminated combustible materials in a waste canister is 5.0E-04 and the ARF for non-combustible
materials in a canister is 6.0E-03. These values represent bounding ARFs for the burning of
contaminated packaged mixed waste and the heating of non-combustible contaminated surfaces
(DOE-HDBK-3010-94, subsections 5.2.1.1 and 5.3.1). 4 The bounding RFs for the burning of
contaminated packaged mixed waste and the heating of non-combustible contaminated surfaces are 1.0
and 1.0E-02, respectively (DOE-HDBK-3010-94, subsection 5.2.1.1 and 5.3.1). 4 . The bounding value
for ARF for burning of contaminated packaged mixed waste is a conservative value. Some of the
conservative factors involved in the determination of the ARF as they apply to this analysis include:
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The experiments on which the determination of ARF are based were designed to represent loosely
packed waste in cardboard boxes. The waste drums that will be temporarily stored in the Hot
Cell are much more substantial (DOT Type A containers). Therefore, the experiments described
in DOE-HDBK-3010-94 4 used to determine the ARF for burning of packaged combustible waste
is conservative for the case being analyzed here.
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Gram quantities were used in the experiments rather than kilogram quantities in the RH waste
containers. The gram quantities of material in the experiments did not provide the depth of burn
residue that may attenuate the airborne releases from large quantities of material. The waste in
the waste drums in this analysis is representative of large quantities of material (up to 1000 lbs
(454 kg) per drum). Additionally, the packaging of the waste in a DOT Type A container will
limit the area of the waste material exposed to the flame. The experiments described in DOE-
HDBK-3010-94 4 used to determine the CARF for combustible packaged waste are conservative
for the accidents analyzed in this SAR.
The radionuclides in the experiments were freshly applied and emphasized the goal of
maximizing release. The experimental configuration did not allow the contaminant material to
attain the degree of adhesion and packing expected for real stored waste and are, therefore,
conservative for the accidents analyzed here.
The experimental configuration, from which the ARF values were obtained, consisted of burning
pre-contaminated wastes packaged in plastic bags, sealed in an 18 in x 18 in x 24 in cardboard
box on a grill in a 10 ft diameter by 10 ft high stainless steel vessel. In the accidents analyzed
here, the volume in which the fire occurs is the Hot Cell which is much larger than the steel
vessel used in the experiments.
5.2-8 January 22, 2003