CAPITAL COST AND TIME REQUIREMENTS

The total cost of a project over its entire life cycle depends on many factors such as the size and homogeneity of the ore body, its mean ore grade, the accessibility of the ore for mining, the amenability of the ore for chemical treatment and the avail-ability of a suitable infrastructure [22]. The components of a project are as follows:

Pre-investment phase (a)

(b) (c) (d)

Exploration

Preliminary feasibility studies Feasibility studies

Licensing (preliminary) Investment phase

(e)

CO

(g)

<h) (i) (j) (k) (1) (m)

Financing

Acquisition of land and mineral rights Engineering

Infrastructure development Mine development Mill construction

Preparation of tailing dam(s) Licensing (final)

Startup Operational phase

(n) Operating cost of the mine

IAEA-TC-453.5/3 13

50 45 40

2 30

JO

0 25 co

1 20 15 10 5

X Coleman and Wick A James and Simonsen

0 500 1000 1500 2000 2500 3000 3500 4000 Tonnes of ore per day

FIG. 4. Capital investment as a Junction of plant size.

(o) Operating cost of the mill

(p) Royalties, marketing and other costs Post-operational phase

(q) Decommissioning

While it is difficult to make generalizations it is clear that the total capital invest-ment required is in the range of several tens to several hundreds of millions of US dollars [23]. For instance, the total cost of the Key Lake Project (Canada) is reported to have been in excess of 500 million Canadian dollars [24].

The capital cost of a metallurgical plant for the production of uranium concen-trates (exclusive of the mine, tailings dams, infrastructure and other items) as a function of plant size has been estimated by James and Simonsen [25] and by Coleman and Wick [26]. These estimates are summarized in Fig. 4.

The time required for the implementation of a project, from the identificaton of a suitable ore body to full production, depends on the size and complexity of the project, the accessibility of the site and availability of a suitable infrastructure, the expertise of the project team, the availability of funds and other factors. Past experience indicates that the time required is in the range of 5 to 15 years [27].

14 AJURIA

7. CONCLUSION

A mining-metallurgical project is costly, lengthy and complex. The implemen-tation of such a project requires a capital investment of several tens to several hundreds of millions of US dollars and from 5 to 15 or more years. The successful implementation of a project also requires a good knowledge of uranium exploration, mining and ore processing, of project management and standard industrial practice for the development of mining-metallurgical projects and of generally accepted methods and criteria for the evaluation of projects.

REFERENCES

[1] NUCLEAR ENERGY AGENCY OF THE OECD, Uranium: Resources, Production and Demand, Joint Report by the OECD/NEA/IAEA, OECD, Paris (1983).

[2] BUNDROCK, G., "From armchair geology to a deposit in a new uranium province", Uranium Exploration Case Histories (Proc. Advisory Group Mtg Vienna, 1979), IAEA, Vienna (1981) 243-277.

[3] NUCLEAR ENERGY AGENCY OF THE OECD, Uranium Exploration Methods (Proc. Symp.

Paris, 1982), OECD, Paris (1982).

[4] PETERS, W.C., Exploration and Mining Geology, Wiley, New York (1978).

[5] INTERNATIONAL ATOMIC ENERGY AGENCY, Methods for the Estimation of Uranium Ore Reserves, An Instruction Manual, Technical Reports Series No. 255, IAEA, Vienna (1985).

[6] INTERNATIONAL ATOMIC ENERGY AGENCY, Uranium Evaluation and Mining Tech-niques (Proc. Symp. Buenos Aires, 1979), IAEA, Vienna (1980).

[7] AHMED, J.U., Occupational radiological safety in uranium mines and mills, Int. At. Energy Agency Bull. 23 2 (1981) 29-32.

[8] THOMAS, K.T., Management of wastes from uranium mines and mills, Int. At. Energy Agency Bull. 23 2 (1981) 33-35.

[9] SEIDEL, D.C., Extracting uranium from its ores, Int. At. Energy Agency Bull. 23 2 (1981) 24-28.

[10] GOW, W.A., "Recent advances in uranium ore processing", Advances in Uranium Ore Process-ing and Recovery from Non-conventional Resources (Proc. Tech. Committee Mtg Vienna, 1983), IAEA, Vienna (1985) 3-13.

[11] NUCLEAR ENERGY AGENCY OF THE OECD, Uranium Extraction Technology: Current Practice and New Developments in Ore Processing, Joint Report of the OECD/NEA/IAEA, OECD, Paris (1983).

[12] MERRITT, R.C., The Extractive Metallurgy of Uranium, United States Atomic Energy Com-mission, Washington, DC (1971) (Reprinted in 1979).

[13] JONES, M.J., (Ed.), Geology, Mining and Extractive Processing of Uranium, The Institution of Mining and Metallurgy, London (1977).

[14] INTERNATIONAL ATOMIC ENERGY AGENCY, Significance of Mineralogy in the Develop-ment of Flowsheets for Processing Uranium Ores, Technical Reports Series No. 196, IAEA, Vienna (1980).

[15] KERZNER, H., Project management: A Systems Approach to Planning, Scheduling and Con-trolling, Van Nostrand, Princeton and New York (1984).

[16] BENNINGSON, L., Project Management, McGraw-Hill, New York (1970).

IAEA-TC-453.5/3 1 5

[17] ALLEN, D.H., A Guide to the Economic Evaluation of Projects, Institution of Chemical Engineers, London (1972).

[18] ALLEN, D.A., Project evaluation, Chem. Technol. 9 7 (1979) 4 1 2 ^ 1 7 .

[19] PARK, W.R., Cost Engineering Analysis: A Guide to the Economic Evaluation of Engineering Projects, Wiley, New York (1973).

[20] SASSONE, P.G.Y., SCHAFFER, W.A., Cost-Benefit Analysis: A Handbook, Academic Press, New York (1978).

[21] UNITED NATIONS INDUSTRIAL DEVELOPMENT ORGANIZATION, Manual for the Preparation of Industrial Feasibility Studies, UNIDO, Vienna (1978).

[22] HOSKINS, J.R., (Ed.), Mineral Industry Costs, Northwest Mining Association, Spokane, WA (1982).

[23] O'HARA, T.A., Quick guides for the evaluation of orebodies, CIM Bull. (Feb. 1980) 87-99.

[24] Key Lake pit development a formidable design challenge, Can. Min. J. (Jun. 1984) 26-27.

[25] JAMES, H.E., SIMONSEN, H.A., "Ore-processing technology and the uranium supply out-look", Uranium Supply and Demand (Proc. 3rd Int. Symp. London, 1978), Mining Journal Books Ltd and The Uranium Institute, London (1978) 113.

[26] COLEMAN, R.B., WICK, K.E., "Factors for cost estimating in uranium ore processing", Eco-nomics of Ore Processing Operations, OECD, Paris (1983) 74-99.

[27] Fuel and Heavy Water Availability, Report of INFCE Working Group 1, IAEA, Vienna (1980) 187.

DISCUSSION

H.J. STEINER: What are the most common errors and causes for delays in the development of projects?

S. AJURIA: A common error that we have often seen in developing countries is the failure to recognize that a certain uranium occurrence is not economical and should perhaps be left aside. There is a tendency to go through with a project no matter what. In fact very few of the uranium occurrences that are found can be exploited economically. One should perform the order of magnitude and pre-feasibility studies and come quickly to a decision whether or not to proceed so as to avoid wasting time and effort.

D.C. SEIDEL: One point where much difficulty has been encountered is in not recognizing the variability of the ore in both grade and mineralogy. There have been very serious difficulties when this variability has not been taken into account when designing the process.

M.C. CAMPBELL: I think one of the biggest sources of problems has been the failure to delineate the ore body properly and to obtain good representative samples.

There have been several cases of people going into production with a process based on a sample that did not in fact represent the ore body. A truly representative sample may be very difficult to obtain. In that case the process must be designed with enough flexibility to cope with the variations that will undoubtedly take place.

IAEA-TC-453.5/18

INTERNATIONAL CO-OPERATION IN RADIATION PROTECTION PRACTICES

IN THE MINING AND MILLING OF URANIUM

J.U. AHMED

Division of Nuclear Safety,

International Atomic Energy Agency, Vienna

A.B. DORY

Atomic Energy Control Board, Ottawa, Canada

Abstract

INTERNATIONAL CO-OPERATION IN RADIATION PROTECTION PRACTICES IN THE MINING AND MILLING OF URANIUM.

Uranium mining industry has been associated with the history of excess lung cancer. Because of such epidemiological evidence, the subject of radiation protection in the nuclear mining industry has received increased attention in recent years both at national and international levels. The radiation hazards encountered in the uranium mining industry result primarily from the exposure to radon daughters. The exposure to external radiation in most mines is low; however, in the mining of high grade uranium ores external radiation exposure can be substantially higher. By adopting proper control measures, namely, regulatory control, appropriate safety standards, monitoring, engineering and other measures, medical surveillance, environmental protection and radioactive waste management, it is possible to minimize the health risk to a level deemed to be acceptable in the light of the benefit derived from the uranium mining industry. Recognizing the history of excess lung cancer among uranium miners and the nature of the associated radiation protection problems there have been considerable national and international efforts to develop safety standards, codes of practice and guides to improve the radiation protection practices for the protection of the workers and the general public. At the international level the role of the International Atomic Energy Agency (IAEA), the International Commission on Radiological Protection (ICRP), the International Labour Organisation (ILO), the World Health Organi-sation (WHO), and the OrganiOrgani-sation for Economic Co-operation and Development/Nuclear Energy Agency (OECD/NEA) has been to develop and provide guidance for improved radiation protection in the uranium mining industry. In the paper the radiological problems in this industry, the types of control measures and the international efforts in harmonizing radiation protection measures are discussed.

1. INTRODUCTION

In the years of uranium production the uranium mining industry grew rapidly in many countries due to the increasing demands of uranium. The rate of growth however has slowed in recent years because of the sluggish growth of the nuclear 17

18 AHMED and DORY

power industry. This situation is not expected to continue, therefore the demand for uranium is likely to increase, though perhaps not at the same rate as in the past.

In Colorado, United States of America, Czechoslovakia, and Ontario, Canada, an excess lung cancer incidence has been observed among underground uranium miners who were exposed to radiation. An excess lung cancer incidence has also been observed among non-uranium miners exposed to radon daughters (fluorspar miners in Newfoundland, Canada, iron ore miners in Sweden).

The radiation risk encountered in the uranium mining industry results primarily from exposure to airborne radioactivity and, to a lesser degree, from external radiation. The inhalation risk is of more concern in underground mining of radioactive ores than in open pit mining.

The excess lung cancer incidence was recognized early in the 20th century among miners in Joachimsthal and Schneeberg but it was really only in the late 1960s and early 1970s that more scientific epidemiological studies of the various groups of miners have been undertaken [1-6].

Although all these studies clearly indicate a causal relationship between exposure to radiation (mainly radon daughters) and lung cancer, the absolute value of risk per unit of exposure is difficult to determine.

This is due to the lack of historical exposure data and uncertainties in the deter-mination of work histories. As the input data were estimated retrospectively, the precision of the data cannot be improved significantly [7]. But qualitatively the evidence clearly indicates the relationship between exposure and incidence of lung cancer.

The epidemiological studies presently under way in New Mexico, Ontario and elsewhere would eventually provide more reliable quantitative risk estimates in the future. Improvements in dosimetric models should also result in risk estimates of higher confidence level in the future.