Cleaning Up Sites Contaminated with Radioactive Materials International Workshop Proceedings (2009) / Chapter Skim
Currently Skimming:
11 Uranium Recovery and Remediation of Uranium Mill Tailings: Russian and U.S. Experience--James H. Clarke and Frank L. Parker
11 Uranium Recovery and Remediation of Uranium Mill Tailings: Russian and U.S. Experience--James H. Clarke and Frank L. Parker
Pages 69-80
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 69... ...
Clarke and Frank L Parker, Vanderbilt University INTRODUCTION Recovery of uranium using conventional mining -- open pit and underground -- to excavate the ore and chemical processing to extract the uranium from the ore generates large volumes of solid and liquid material (uranium mill tailings, or UMT)
|
From page 70... ...
. However, most uranium mining wastes in the United States have come from conventional mining operations, both surface and underground, from 1957 to 1989 (World Nuclear Association, 2007)
|
From page 71... ...
mill tailings program: "I was recently in Wyoming with Chinese colleagues to visit uranium mining and milling remediation sites. I was struck by the hundreds of millions of dollars being spent to protect a population that might be there in 200 to up to 1,000 years in the future from statistical deaths.
|
From page 72... ...
72 CLEANING UP SITES CONTAMINATED WITH RADIOACTIVE MATERIALS FIGURE 11-1 A view of a portion of the Wismut facilities. Figure 11-1.eps Bitmap image - Low resolution FIGURE 11-2 Location of uranium mines in the western United States.
|
From page 73... ...
URANIUM MILL TAILINGS REMEDIATION IN THE UNITED STATES: THE URANIUM MILL TAILINGS RADIATION CONTROL ACT (UMTRCA) OF 1978 While UMTs typically contain relativity low activity, they are perceived by many to constitute a serious hazard based on their very large volume.
|
From page 74... ...
. RISKS ASSOCIATED WITH UMT SITES As indicated above, the sheer volume of waste at UMTs, despite the relatively low activity associated with the tailings wastes, has engendered a perception that UMT sites pose a serious hazard and potential risk to human health and the environment.
|
From page 75... ...
The cover is composed of a 1.5-foot-thick transition layer placed directly on the radioactive materials; a 2-foot-thick clay layer serving as the radon barrier and minimizing water infiltration; a 2-foot-thick layer of clay above the radon-infiltration barrier minimizing freeze-thaw damage; a 6-inch-thick coarse-grained bedding layer covering the freeze-thaw barrier to minimize capillary movement of fluids and FIGURE 11-3 Mill tailings cover design, Durango, Colorado. Figure 11-3.eps Bitmap image - Low resolution
|
From page 76... ...
PERFORMANCE ISSUES AND MONITORING When considering the design approach for an engineered cover at a UMT site, local climate and environmental factors are important, as the cover design is dependent upon rainfall and infiltration rates. At some sites, however, the engineered covers are experiencing degradation as a result of natural processes, especially erosion and root intrusion (biointrusion)
|
From page 77... ...
These models should be validated and calibrated using the results of field observations and measurements." Closed UMT sites in the United States are monitored annually, including physical inspections of cover integrity and access restrictions such as signs and fences. While a requirement for perpetual monitoring and maintenance of these sites is unrealistic, it is noted that the general NRC license contains no expiration date.
|
From page 78... ...
78 TABLE 11-2 Remediation of UMTRCA Title I Uranium Mill Sites Under the UMTRA Project Summary Table: Uranium Ore Processed, Disposal Cell Material, and Cost for Remediation as of December 31, 1999 Uranium Ore Processed Disposal Cell Remediation Project Cost Ore Uranium Remediated Total Cost Per Pound Per Unit of Per Unit of (Million Production Material Volume (Thousand Produced Remediated Material Radiation Avoided Remediation Project Short (Million (Million Cubic U.S. (Dollars per (Dollars per Cubic (Dollars per Curie, (Mill Site Name, State)
|
From page 79... ...
Annual Site Inspection and Monitoring for Uranium Mill Tailings. Radiation Control Act Title I Disposal Sites, DOE Office of Legacy Management DOE-LM/GJ1015 -- 2005, December.
|
From page 80... ...
Washington, D.C.: The National Academies Press. Presented at the International Workshop on Cleaning Up Sites Contaminated with Radioactive Materials, Moscow, Russian Federation, June 4-6, 2007.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.