Safe, reliable, efficient extraction of 5,100 cubic yards of low-level radioactive waste raffinate from a concrete silo without an outlet after over 50 years storage at rest was a challenge Fluor Fernald faced. Due to the hazardous nature of the material, a retrieval system had to be designed and installed so as to work reliably and without a dust incident throughout the reclamation of material.

With safety as a top priority, it was determined that the flow behavior of the material during extraction as well as during flow through the system was necessary as a design basis. Also, Fluor wanted the capability to simulate the material's stability during extraction so as to assess potential risks.

Core sampling of the contents and flow property testing were undertaken. Using the results, a study and simulation were prepared based on the anticipated means of retrieval. The results lead to the installation and operation of a pneumatic and mechanical retrieval system that operated without incident, while maintaining the project schedule on time and budget.

This paper reviews key findings and results from the effort.