NUREG-1537, Part 2 - NRC

APPDIX 1 8.1
mechanical failure or degradation related to neutron irradiation, corrosion, and
erosion. Additionally, modifications to the biological shield or to reactor operating
characteristics will be acceptable (1) if they do not decrease physical integrity of
the shield against crackdng or other structural malfunctions due design loads (eg.,
natural or reactor-induced forces) or neutron irradiation and (2) if the protection of
the radiation shielding does not decrease below acceptable requirements as
analyzed in Chapter 11 of the staffs safety evaluation report.
Review Procedures
The reviewer should compare design changes against the as-built systems to
confirm how proposed changes will affect the structural integrity, resistance to
failure or degradation, or radiation protection factors of the pool and biological
shield for normal operations or postulated accident conditions.
Evluation Findings
This section of the SAR should contain sufficient information to support the
following types of conclusions, which will be included in the staff's safety
evaluation report:
* Any proposed chafiges to the poof or to the biological shield for the
conversion are required to accommodate the'conversion.
* Proposed modifications to the pool, shield, or reactor operating conditions
will not significantly decrease resistance to failure, or cause new or
accelerated degradation or loss of integrity.
* Any new conversion-related pool or shield safety issues are addressed by
proposed modifications to the pool and shield systems.
* (If no chages to the pool or biological shield are proposed) The
information submitted supports the conclusion that the existing systems
will provide comparable protection to the public with the LEU fuel.
4.4 Core Support Structure
Areas of Review
The reviewer should evaluate the design features, construction materials, criteria
for rigidity and weight support, and capability to maintain fuel and other core
components in acceptable positions. The reviewer should also compare the weight
and other relevant stresses imposed by the existing HEU core components to those
of the proposed LEU core components.
NUREG-1537, PMT2 12 REV. 0,2/96
NUREG-1537; PART2 12 REV. 0, 2/96
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