IAEA-TECDOC-492 IN SITU LEACHING OF URANIUM: TECHNICAL, ENVIRONMENTAL AND ECONOMIC ASPECTS PROCEEDINGS OF A TECHNICAL COMMITTEE MEETING ORGANIZEE TH Y DB INTERNATIONAL ATOMIC ENERGY AGENCY AND HEL VIENNADN I 6 NOVEMBE3- , R 1987 A TECHNICAL DOCUMENT ISSUED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1989 IN SITU LEACHIN URANIUMF GO : TECHNICAL, ENVIRONMENTAL AND ECONOMIC ASPECTS IAEA, VIENNA, 1989 IAEA-TECDOC-492 ISSN 1011-4289 Printed by the IAEA in Austria January 1989 PLEAS AWARE EB E THAT MISSINE TH AL F LO G PAGE THIN SI S DOCUMENT WERE ORIGINALLY BLANK The IAEA doe t normallsno y maintain stock f reportso thin si s series. However, microfiche copie f thesso e reportobtainee b n sca d from INIS Clearinghouse International Atomic Energy Agency Wagramerstrasse 5 P.O. Box 100 A-1400 Vienna, Austria Orders should be accompanied by prepayment of Austrian Schillings 100, for e for e chequa th f m th IAEf m o n i o n i r eAo microfiche service coupons orderee whicb y hdma separately fro INIe mth S Clearinghouse. FOREWORD Within the framework of its activities in nuclear raw materials the International Atomic Energy Agency has convened a series of meetings to discuss various aspect uraniuf so processine mor g technology, recovery of uranium from non-conventional resource developmend san projectf to s productioe foth r uraniuf no m concentrates including economic aspects. As part of this continuing effort to discuss and document important aspects of uranium production the IAEA convened a Technical Committee Meeting on Technical, Economic and Environmental Aspects of In-Situ Leaching. f thio Althoug se us techniqu e hth limites i e y b d geological and economic constraints, it has a significant potential to produce uranium at competitive prices. This is especially important in the current uranium market whic mainls i h y characterise largy db e inventories, excess production capability and low prices. This situation is not expected to last indefinitely but it is unlikely to change drastically in the next ten years or so. This Technical Committee Meeting was held in Vienna from 3 to 6 November 1987 with the attendance of 24 participants from 12 countries. Eight papers were presented. Three technical sessions covered in-situ mining research, environmental and licensing aspects and restoration of leached orebodies fourtA . h sessio s dedicate nwa presentatioe th o t d n and discussion of national reports from several Member States. Four Panels were held to discuss the technological status of in-situ leaching, the current statu d futursan e prospect in-sitf so u leachin uraniuf o g n i m Member States, general aspect planninf so d implementatioan g in-sitf o n u projecteconomice th d san in-sitf so u leaching. The Agency wishes to thank the participants and their Member States for their valuable contributions to the Meeting and the discussions. Thank Chairmee especialle technicae sth ar th o t f no e ydu l sessions and panels, Messrs. W. Larson (United States), A. H. Montgomery (United States), G. Schmidt (Federal Republic of Germany) and D. C. Seidel (United States). The officers of the IAEA responsible for the organization of the meeting and for editing the proceedings were Mr. J.L. Rojas and Mr. S. Ajuria of the Division of Nuclear Fuel Cycle who also chaired Panel Discussion IV. EDITORIAL NOTE In preparing this material for the press, staff of the International Atomic Energy Agency have mounted and paginated the original manuscripts as submitted by the authors and given some attention to the presentation. The views expressed in the papers, the statements made and the general style adopted are responsibilitythe namedthe of authors. necessarilyviewsnot The do reflect govern-thosethe of ments Member ofthe States organizationsor under whose auspices manuscriptsthe were produced. thisin The bookuse of particular designations countriesof territoriesor does implynot any judgement publisher,the legalby the IAEA, to the status as suchof countries territories,or of their authorities and institutions or of the delimitation of their boundaries. The mention of specific companies or of their products or brand names does not imply any endorsement recommendationor IAEA. partthe the of on Authors are themselves responsible for obtaining the necessary permission to reproduce copyright material from other sources. CONTENTS Introduction to in situ leaching of uranium .............................................................. 7 J.L. Rojas A brief analysis of the supply and demand of uranium ................................................ 21 J.L. Rojas Uraniu sitmn i u mining researc Unitee th y hb d States Burea f Mine uo revie A — s w .........7 3 . J.M. Pugliese, W.C. Larson Restoration of in situ leached uranium ores: a laboratory study of restoration reagents ........ 63 D.C. Grant, H.A. Burgman, D.C. Seidel Adapting uranium in situ mining technology for new commercial operations .................... 75 A.H. Montgomery Groundwater restoratio stabilizatiod nan Ruth-ISe th t na L test sit Wyomingn ei ........A 7 9 US , . C. Schmidt In situ leaching of Yozgat-Sorgun-Temrezli uranium deposit — Related laboratory experiments .................................................................................................7 12 . G. Öner, Nasün,G. A.I. Çatalîa§, OkutanH. In situ leaching of uranium in the USSR ................................................................. 143 J.I. Skorovarov, R.H. Sadykov, V.D. Nosov Potentialities of percolation leaching of uraniferous siltstone from Wadi-Nasib, Egypt ......... 153 M.A. Mahdy PANEL DISCUSSIONS Panel 1: Status and trends of the technology of in situ leaching .................................... 161 Pane : Summarie2 l f nationaso l experienc sitn i un ei leachin g ......................................3 16 . Pane : Developmen3 l sitn i uf o tleachin g projects .....................................................7 16 . Pane : Economi4 l c considerations ........................................................................9 16 . Lis f Participanto t s ...........................................................................................1 17 . INTRODUCTIO SITN I UO N T LEACHIN URANIUF GO M J.L. ROJAS Division of Nuclear Fuel Cycle, International Atomic Energy Agency, Vienna Abstract As an introduction to the several discussions on in-situ leaching, the main concepts of this technology are reviewed in orde clarifo t r y some important ideas suc: geologicahas l constraints, hydrology, aquifer restoration, environmental impacts and future trends. In-Situ Leachin solutior go n minin terme ar gdescribo st procesea s for contacting a mineral deposit with leaching fluids to dissolve the mineral without having physically to remove the ore from where it is naturally placedselectivs i t I . than i e t mostly onlminerae th y f lo interest is stabilised and flows to the surface for recovery. It is technically classified as a mining method although it does not involv classie eth c concep minin f excavatiotn o a s oree ga th . f no In-situ leach is a new technological development that began in 1974. During this timtechniquese th e , method equipmend procese san th r stfo from basic concept successfuo st l commercial realisatioe b o t d nha developed. aspecte th Thes e sear that could determin characteristice th e f so the In-Situ Leaching (ISL) process: e mosTh t importanpotentiae th s ha s thao i tt lt i taspecL IS f to produce uranium at lower costs (less capital investment and lower operating cost poundr spe ) than other mining method properlf i s y applied by an experienced operator to a suitable ore deposit. The second most important aspect is that this method is limited to only one type of uranium deposit; a roll front (deposited from moving groundwater) deposit ipermeabla n e sandstone that aquife n a mus e tb r (sandstone filled with water). The third most important aspect is that it is difficult to predict the performanc projectL IS n a .f eo There have bee greana t many more unsuccessful than successfu projectsL lIS . Since this process involves several competing chemical reactions taking place undergroun naturaa n di l uranium deposit chemicae ,th d geologicalan l parameters affecting flow rates, reaction rates uraniud ,an m production vary significantly froe mon ore deposi anotheo t d indeeran d even withi same th ne deposit. Several companies have developed methods of testing and evaluating these deposits which include laboratory core leach studies, pump tests (hydrology studies) in the field, core analysis, logging techniques, and pilot leach projects. However possiblt ,no s sinc i quantifo t et i e y completely the parameters of a deposit which determine the effectiveness leachine oth f g process experience ,th operatoe th f a eo n ri wit L hIS variet f geologicao y l setting relatinn i d an s g laborator pilod an y t performance to commercial performance is important in achieving a reliable low cost operation. In addition, in situ leaching of uranium is more sensitiv gooo et d engineering managemen d attentiotan detaio nt l than other types of uranium mining. Prior to the operation of an in-situ leach mining facility it is necessar colleco yt geology) t (1 dat : hydrology) aon (2 , ) in-sit(3 d ,an u leaching mining impacts. A portion of the principal items considered under each of these headings is given below. A. Geology Regional geologic structure and seismicity Regional stratigraphy Cross sections through the mining site depicting the location and confinine th zone d or ean e gtrenth bedf o ds Isopach, contour structurr ,o minine mapth f gso site . HydrologB y Water levels (potentiometric levels ore-zone th f )o e e aquifeth d ran aquifers abov belod an e w Regiona locad lan l direction ground-watef so r flow Total and effective porosity and permeability of the ore-zone aquifer Water quality of the ore-zone aquifer including the ore body and both upgradient and downgradient areas Water quality of the aquifers above and below Competenc confinine d extenth ean f to g beds A.