Radon from uranium mills

Mill tailings are another form of nuclear waste. The residue from uranium ore extraction contains radium, the precursor of short-Hved radon and its daughters. Piles of tailings must be properly covered. 

The presence of radiation in the workplace - which is an inevitable consequence of the radioactivity of uranium - requires that additional safety precautions be taken over and above those observed in other similar workplaces. There are generally three sources from which radiation exposure may occur (i) radiation emitted from uranium ore in-situ and/or during handling (ii) airborne radiation resulting from the decay of radon gas released from the ore and uranium dust and (iii) contamination by ore dust or concentrate. Radiation levels around uranium mining and milling facilities are quite low - for the most part only a few times the natural background levels - and they decrease rapidly as the distance from... 

EPA. 1986b. U.S. Environmental Protection Agency. Pinal rule for radon- 222 emissions from licensed uranium mill tailings. Background information document. Report. EPA 520/1-86-009. NTIS PB87-207569. 

T Radon from the Disposal of Uranium Mill Tailings Radon 12/15/89 7/15/94... 

Uranium-contaminated waste, principally from mining, milling, and enrichment. Under some circumstances uranium s 15-hour radon decay product requires dditional control. The uranium tails from enrichment generally are not included in waste tabulations because in time they may be incorporated as a fertile material in breeding. 

Mill Wastes. The uranium-containing wastes from milling are mounded and covered with earth. This earth cover prevents erosion and delays for decay the 14-hour radon gas, the gaseous decay product of uranium. These mill waste repositories are located near the mines and mills and are not a very different hazard from the original naturally occurring uranium deposits. The depleted uranium from the enrichment operations is stored in cylinders as uranium hexafluoride for future use in the uranium-plutonium breeding cycle. Other uranium wastes from enrichment and fuel fabrication go to the low-level repositories. 

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