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

WIPP RH PSAR DOE/WIPP-03-3174 CHAPTER 4
4.4 Confinement Systems
The WIPP facility confinement system consists of static and dynamic barriers designed to meet the
following requirements of DOE Order 6430.1A, 1 Section 1300-7:
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Minimize the spread of radioactive and other hazardous materials within the unoccupied process
areas.
Prevent, if possible, or minimize the spread of radioactive and other hazardous materials to occupied
areas.
Minimize the release of radioactive and other hazardous materials in facility effluents during normal
operation and anticipated operational occurrences.
Limit the release of radioactive and other hazardous materials resulting from Design Basis Accidents
(DBAs) including severe natural phenomena and man-made events in compliance with the guidelines
contained in DOE Order 6430.1A, 1 Section 1300-1.4.2, Accidental Releases.
In addition to the above requirements, the WIPP is designed to meet the specific confinement
requirements of DOE Order 6430.1A, 1 Section 1324-6 and Section 1300-1.4.
Static barriers are structures that confine contamination by their physical presence, while dynamic
barriers control the flow of contamination in the air. For the WIPP, static barriers consist of waste
containers, building structures, geological strata, and HEPA filtration systems; dynamic barriers consist
of the surface and subsurface ventilation systems that maintain pressure differentials ensuring airflow is
from areas of lower to higher contamination potential.
For the WIPP, the primary confinement is the static barrier consisting of the waste containers, and the
secondary confinement consists of those SSCs designed to remain functional (following DBAs) to the
extent that the guidelines in DOE Order 6430.1A, 1 Section 1300-1.4.2, Accidental Releases, are met.
Consistent with DOE Order 6430.1A, 1 Section 1324-6, tertiary confinement is not required for the WIPP
during disposal operations.
Confinement system design within DOE Order 6430.1A, 1 requirements meets the requirements of DOE
O 420.1, Facility Safety. 2
4.4.1 Waste Handling Building
Static and dynamic barriers are incorporated into the design of the WHB confinement system, and the
primary confinement is the canister holding the waste.
The secondary confinement consists of the SSCs that house the primary confinement, including the
shielded road cask, the shipping canister when loaded with 55-gallon drums, the rooms, the building
walls, and the ventilation system, which maintains a static pressure differential between the primary
confinement barriers and the environment. To assist the ventilation system, "air locks" are provided
between separate areas where pressure differentials are necessary. The WHB HEPA filtration system
connects with the ventilation systems and provides the final barrier for airborne particulates.
4.4-1 January 28, 2003