Abstract: Concrete support ledges (67) and columns (94) for the upper internals (60) and lower internals (63) structures are poured into the floor (41) and walls (36) of the refueling cavity (33) at the time of initial plant construction. Such concrete supports (67, 94) provide greater stability and do not require any external bracing. A pedestal assembly (100) is associated with each of the concrete supports (67, 94) to provide an adjustable and secure support for the internals structures (60, 63).

Abstract: A radiation shield (10) is comprised of three, equiangularly extending, arcuate sections (14) which are secured to the nuclear reactor pressure vessel closure head (12) so as to annularly surround the nuclear reactor control rod drive mechanisms (26) and thereby prevent radiation emanating from the mechanisms (26) from reaching maintenance personnel who may be operatively working within the peripheral section (20) of the closure head. The shield sections (14) are bolted together by fasterners (18) and are secured to closure head lift lugs (30) by means of mounting brackets (38) and transversely extending pins (36). Clevis assemblies (34) are also pinned to the mounting brackets (38) and lift lugs (30), and lift rods (32) are threadedly engaged with the clevis assemblies (34). In this manner, when the closure head (12) is lifted from its associated pressure vessel, the radiation shield (10) remains with the closure head (12).