Uranium Resource Estimates

Reasonably Assured Resources refers to uranium which occurs in known ore deposits of such grade, quantity and configuration that it could be recovered within the given production cost range with currently proven. . . technology. Estimates of tonnage and grade are based on specific sample data and measurements of the deposits.  

Estimated Additional Resources refers to uranium surmised to occur in unexplored extensions of known deposits in known uranium districts, and which is expected to be discoverable and could be produced in the given cost range. 

Country assured additional Total assured additional 50/lb UjOg 1977 1985 

Source Organization for Economic Cooperation and Development, and International Atomic Energy Agency, Uranium Resources Production and Demand, Paris, Dec. 1977. 

1 MT uranium = 1 tonne uranium = 1 Mg uranium = 1.102 short tons uranium = 1.300 short tons UsOg. 

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The only major alternative for India is nuclear energy. However, the potential of natural uranium resources, estimated to be around 50,000 tonnes is negligible [about 1 bt of coal equivalent (btce)] if utilised in an once-through cycle and the capacity also will be limited to about 10 GW(e). If the same U along with the Pu generation in PHWR is invested in FBR the... 

The U.S. Department of Energy (DOE) and the NEA/IAEA employ similar terms to classify uranium resources, as (7) reasonably assured, estimated additional (EA), or speculative. The NEA/IAEA divides the estimated additional resources into two types, EAR-I and EAR-II, describing known resources and undiscovered ones, respectively (8). 

Domestic. Estimates of U.S. uranium resources for reasonably assured resources, estimated additional resources, and speculative resources at costs of 80, 130, and 260/kg of uranium are given in Table 1 (18). These estimates include only conventional uranium resources, which principally include sandstone deposits of the Colorado Plateaus, the Wyoming basins, and the Gulf Coastal Plain of Texas. Marine phosphorite deposits in central Elorida, the western United States, and other areas contain low grade uranium having 30—150 ppm U that can be recovered as a by-product from wet-process phosphoric acid. Because of relatively low uranium prices, on the order of 20.67/kg U (19), in situ leach and by-product plants accounted for 76% of total uranium production in 1992 (20). 

Foreign. The OECD/NEA and IAEA have issued annual reports on world uranium resources, production, and demand since the mid-1960s (2—6). NEA/IAEA data for reasonably assured and estimated additional resources at costs of 80 and 130/kg uranium are given in Table 2 (21). These estimates incorporate data from both former world outside centrally planned economies (WOCA) and non-WOCA nations. A summary of other known uranium resources with and without cost range estimates is provided in Table 3 (22). These resources total about 1.4 x 10 t and include estimates that are not strictly consistent with standard NEA/IAEA definitions. 

Estimates of speculative lesouices (SR) at 130/kg uianium and those having an unassigned cost range are provided ia Table 4 (23). These resources, which total about 11.28 x 10 t, would be ia addition to the reasonably assured and estimated additional resources. Estimates of uranium resources from unconventional and by-product sources are presented ia Table 5 (24). These resources total about 7 x 10 t for phosphates, 0.013 x 10 t for nonferrous ores, 0.016 x 10 t for carbonates, and 0.014 x 10 t for lignites. These would be ia addition to the reasonably assured resources, estimated additional resources, and the speculative resources (24). 

Resource estimates are divided into separate categories reflecting different levels of confidence in the quantities reported, and further separated into categories based on the cost of production. A listing of uranium resources by country is given in Table 3. 

Another potentially vast resource is seawater. Uranium resources associated with the oceans are estimated at around 4000 million tonnes however, the uranium concentration in seawater is only around 0.003 ppm. The recovery of uranium from seawater is still subject to basic research. Considerable technological developments as well as significant improvements of economics (or drastic increases in uranium prices) are crucial for the commercial use of this resource, which is unlikely in the foreseeable future. As the energy demand for uranium extraction increases with lower concentrations, the net energy balance of the entire fuel cycle is also critical. 

Currently, Uracan Resources Limited owns claims to the Main Double S Zone, as well as two other mineralized zones (Middle Zone and TJ Zone) within the North Shore Property. These three zones combined contain a total inferred resource estimate of 154.9 million tonnes at an average grade of 0.012% UaOs and contain 18.48 million kilograms (40.73 million pounds) of uranium using a 0.009% cut off (Uracan website). These resources outcrop at surface, are open at depth and along strike. 

Current estimates of the available reserves and further resources of uranium and thorium, and their global distribution, are shown in Figs. 5.44-5.50. The uraruum proven reserves indicated in Fig. 5.44 can be extracted at costs below 130 US /t, as can the probable additional reserves indicated in Fig. 5.45. Figure 5.46 shows new and unconventional resources that may later become reserves. They are inferred on the basis of geological modelling or other indirect information (OECD and IAEA, 1993 World Energy Council, 1995). The thorium resource estimates are from the US Geological Survey (Hedrick, 1998) and are similarly divided into reserves (Eig. 5.47), additional reserves (Fig. 5.48) and more speculative resources (Fig. 5.49). The thorium situation is less well explored than that of uranium the reserves cannot be said to be "economical", as they are presently mined for other purposes (rare earth metals), and thorium is only a byproduct with currently very limited areas of use. The "speculative" Th-resources may well have a similar status to some of the additional U-reserves. 

Figure 5.50. All estimated uranium resources (sum of Figs. 5.44-5.46), here given as kt of uranium oxide per m averaged over each coimtry (from Sorensen, 1999).

The oceans contain about 4.5 billion tons of dissolved uranium, almost a thousandfold of the reasonably assured and estimated terrestrial uranium resources in the western world 101). The concentration of uranium in sea water appears to be remarkably constant at about 3.3 pg/liter 120-122). Very recent measurements of uranium concentrations in sea water samples taken in the Arctic and South Pacific Ocean down to depths of more than 5000 m confirm this mean value 123). However, with increasing salinity of sea water a slight increase of uranium concentration is observed 124). The molar concentration of uranium in sea water is nearly 8 orders of magnitude lower than the total concentration of the major ions 125). Marine uranium displays no detactable deviation from the normal terrestrial U-235/U-238 isotope ratio, 03>126). 

An estimate of uranium resources in the United States more detailed and more recent than that of Table 5.17 provided by the U.S. Department of Energy in May 1978 [Ul] is summarized in Table 5.18. Reserves corresponds approximately with the Reasonably assured resources category of Table 5.17, and Probable potential resources corresponds with Estimated additional resources. The subtotal at < 30 of 1312 thousand MT in Table 5.18 may be considered an update of the 1361 for the United States in Table 5.17, and the subtotal at < 50 of 1758 thousand MT in Table 5.18, an update of the 1696 in Table 5.17. 

To relate these resource estimates to nuclear electric generation, it may be noted that a 1000-MWe pressurized-water reactor operating at 80 percent capacity factor without recycle, on uranium enriched to 3.3 w/o (weight percent) U in an enrichment plant stripping natural uranium to 0.3 w/o U, consumes around 200 MT of uranium per year. Thus the U.S. resource estimate of 1758 thousand MT available at less than 50/lb UgOg would keep a 300,000-MWe nuclear power industry in fuel for... 

We shall estimate the resources for nuclear fission, breeder, and fusion reactors by using geological data. In breeder reactors, the fertile isotopes U-238 and Th-232 are converted to the fissile isotopes U-233, U-235, Pu-239, and Pu-241 as the result of neutron capture. Thorium is a very widely distributed element and does not represent a limiting supply when used in breeder reactors with uranium. For this reason, the following discnssion is restricted to uranium resources for fission and breeder reactors. 

The current availability of uranium is generally specified in terms of availability at a specified price. A 1983 DOE estimate for the United States was 433,400 t of U at 80/kgU, corresponding to the sum of the probable potential (251,500 t), possible potential (98,800 t), and speculative potential (83,100 t) resources at 260/kg U, the corresponding values were 725,700-1-323,800-1-250,700 = 1,300,200 t of U. Uranium prices declined from nearly 110/kg in 1980 to about 40/kg by mid-1984 and remained at about this level during the next 4 years. Needless to say, the current availability in the United States and elsewhere of uranium resources even at the highest prices is smaller by mat r orders of magnitude than the ultimately available resources. A similar remark applies to resources outside of the United States. Thus, the total Western world lesouices (not including the centrally planned economies) were estimated in 1987 to exceed the U.S. resources by factors of about two to four. In 1981, the United States was the world s dominant nraninm producer, with 33.5% of total Western production by 1986, the U.S. share had declined to 14.3%, while Canada had become the dominant producer with 31.6% of total production. In 1986, South African (at 12.5%) and Australian (at 11.2%) production followed U.S. production closely. 

Brazilian uranium resources are presently estimated in 300,000 metric tons and the estimate on the thorium resources is of the order of one million metric tons. The country has presently one reactor (PWR/626 MWe) in operation and a second one (PWR/1300 MWe) has recently received authorization for completion, which is planned for 1999. A third reactor (PWR/1300 MWe), originally planned to be constructed in the same site as the other two is still awaiting for a government decision. 

The most important advantage of these gas core concepts, however, may lie in the fact that they can be designed as breeders but with minimal initial fissile feed requirements. This point is significant for two reasons (a) the rate at which these gas core reactors could be brought on line would not be dependent oh the rate of fuel being discharged from LWRs as would be the case fpr LMFBRs and b) the estimated easily recoverable U.S. uranium resources will probably be sufficient to fuel 500 to 1000 LWRs of 1000 MW(e) each, while this same amount of uranium could be used to fuel approximately... 

So with >384 GW in operation today (predominantly supplied from conventional uranium mines) present world demand is -70,000 t/a. We can provide an upper bound estimate of demand for 5000 GW of new reactors needing -one million t/a by 2050. Today s estimates of proven uranium reserves af a cosf of < 130/kg is about six million tons (IAEA and OECD-NEA 2005). Even allowing that exploration will likely lead to a doubling or tripling of the resource estimate to, say, 20 MtU, just 2000 reactors operating for 60 years would use all the world s cheapest uranium with present fuel cycles technology. 

Mr. Pahissa-Campa observed that uranium resources are not as great as originally estimated. He emphasized the nuclear energy being essential for at least the coming 50 years and that one must not squander uranium reserves as it was done with petroleum. This means that the spent fuel should be considered not as a common waste but as potentially reusable material. Safe, reliable and retrievable storage should be the approach until a definitive decision is taken. 

Uranium, relatively abundant in the earth s crust, being present on average at a concentration of 4ppm, is also present in sea water at concentrations of the order of 0.003 ppm. Enormous resources of uranium are therefore available, ocean waters containing an amount equal to some thousand million tons. The effective available uranium resources are, however, estimated on the basis of deposits that contain higher concentrations from which uranium can be extracted at various costs, though not more than 130/kg. On this basis the reasonably assured and additional estimated uranium resources are shown in... 

Besides the resources estimated at 130/kg there exist other uranium sources, generally with a lower content and at a higher extraction cost. These are either an extension of conventional uranium deposits cultivated at 130/kg or conventional deposits the extraction cost of which exceeds 130/kg because of their limited size, deep location or presence in remote areas. Examples of these additional uranium sources are the vast high-cost resources associated with the Elliot Lake deposits in Canada, the 5000-10000 ton of uranium at costs of more than 130/kg in Italy, the 12000 ton contained in granitic rocks at a cost of 130- 260/kg in Namibia, the 141000 ton contained in the conglomerates and the 46000 ton in the surface sediments in South Africa at a cost of 130- 260/kg and the vast quantities of uranium contained in the sandstones of Colorado, Wyoming and New Mexico. 

Table 5.1. Estimated Uranium Resources in Kilotonnes, for Non-Communist...

Reasonably assured resources below 80 per kg amount to 2.5 million tonnes of uranium, while RAR resources below 130 per kg amount to around 3.2 million tonnes. (This equals 1230 PJ and 1585 PJ, respectively, assuming that 1 tonne of uranium yields around 0.5 PJ (BGR, 2007).) IR below 80 per kg amount to roughly 1.1 million tonnes and below 130 per kg to approximately 1.4 million tonnes. Total RAR and IR sum up to almost 4.6 million tonnes (2280 EJ). Total undiscovered resources are estimated at 7.5 million tonnes. On top of these resources comes uranium from sources such as energy companies stocks, nuclear arms uranium, etc. 

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