212-N Building basis of interim operation

This document presents the Basis of Interim Operation (BIO) for the 212-N Building surveillance and maintenance (S and M) work in the 200 North (200-N) Area of the Hanford Site. The residual wastes of the 200-N Area are contained within a single operable unit, 200-NO-1 (WHC 1992). This document addresses only the 212-N Building. The waste sites that are associated with this building are excluded from the scope of this document, and any discussions regarding these sites are included only for information. Final disposition of the buildings and waste sites is not yet scheduled, pending decisions by the US Department of Energy (DOE) and external regulators. Evaluation of legacy inventories of hazardous substances in retired facilities found that the 212-N Building potentially contains significant quantities of hazardous and radioactive materials (BHI 1998a). Hazards with the potential to cause release of these materials to the environment or cause exposure to individuals are evaluated to verify the controls necessary to manage the hazards. The documented radiological inventory was found to exceed the threshold and defined a Preliminary Hazard Classification (PHC) of Nuclear (BHI 1997b). This BIO presents information in several sections. Section 1.O provides an overview and summarizes the analyses performed. Section 2.0 provides the background information necessary to understand the hazards that have the potential for creating an accidental release of, or accidental exposure to, hazardous substances. Section 3.0 defines the workscope and confinement functions that are applicable to S and M of the 212-N Building. Section 4.0 identifies the hazards, evaluates potential consequences (of upset and accident conditions), identifies needed control features, and presents the final hazard classification (FHC). Section 5.0 describes applicable project-specific, special, and programmatic controls that are necessary to safely manage the S and M mission. Section 6.0 contains the relevant references used to prepare this document. Appendices A and B contain detailed analyses related to the Preliminary Hazard Analysis (PHA) and the Fire Hazard Analysis (FHA), respectively.