[en] The High-Radiation-Level Chemical Development Facility includes Buildings 4507 and 4556. Building 4507, located immediately to the west of Building 4500N and to the south of Building 4505, is a doubly contained three-level structure constructed in 1957. The most recent use of the facility was for recovery of multi-gram quantities of ²⁴⁴Cm during the early 1970s and for Liquid Metal Fast Breeder Reactor (LMFBR) fuel studies in the late 1970s. It has remained in safe standby since 1980. Building 4556 is a below-grade filter pit located to the southwest of Building 4507 and was constructed in 1972. Ventilation from the cells in Building 4507 is passed through high-efficiency particulate air (HEPA) filtration in this building prior to being exhausted to the Building 3039 stack system. This building remains in operation to support ventilation requirements for Building 4507. This Auditable Safety Analysis (ASA) was developed in accordance with the requirements in Energy Systems Program Description FS-103PD, Safety Documentation, Revision 1. This ASA identifies and screens all hazards associated with Buildings 4507 and 4556. The only hazard not screened out and requiring further analysis following the initial screening process is radioactive material in the form of surface contamination. The results of this ASA indicate that the hazards associated with Buildings 4507 and 4556 do not pose a significant threat to workers, the public, or the environment