IMPROVING PROCESS CONTROLS AT IN-SITU LEACHING URANIUM MINES

The U.S. Department of Energy’s National Nuclear Security Administration (NNSA), the Kazakhstan Atomic Energy Committee (KAEC), and Kazatomprom are cooperating in an effort to improve process controls at in-situ leaching uranium mines. Historically nuclear material at uranium mines was not subject to detailed accounting and control procedures under IAEA Safeguards Agreements. Consequently Kazakhstan’s State regulations on nuclear material accounting and control did not apply to natural uranium mining and concentration facilities. Kazatomprom recently instituted new corporate requirements for nuclear material accounting and control at its mines. Kazatomprom has initiated a plan to strengthen these requirements and to implement improved procedures for accounting and control in support of this effort. NNSA, KAEC, and Kazatomprom are cooperating on a study to assess new approaches for strengthening process controls at in-situ uranium mines. The results of this study could improve the timeliness and quality of the data that is used in the uranium accounting systems. The US/Kazakh team will evaluate systems involving commercial off-the-shelf (COTS) equipment that could provide realtime accounting of uranium as it is extracted from each wellhead and perform a mass balance on the entire process automatically. The process would cover pumping the pregnant solution for individual wells, through resin exchange, precipitation, filter-pressing and finally placing the yellowcake in drums for shipment. The study will be conducted at two Kazakhstani uranium mines: Appak and Zarechnoye. This paper addresses the initial efforts to define the scope of the program and the technical approaches to developing user requirements.