[en] Technical conditions are evaluated of bearing and fencing structures of deaerator building with considering additional in-situ investigation data and results of estimate of integrated spatial model of Unit B and deaerator. Model estimate is made of carry-over of dust that can rise after collapsing of bearing structures of upper tiet of deaerator framing when southern zone of localizing case will be open. Volumetric concentration of radioactive aerosols and surface contamination of local zone ground,on 'Ukryttia' industrial site and within 10 - and 30 - km zone surrounding ChNPP, were defined