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Design Guide for Metal and Nonmetal Tailings Disposal

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Design Guide for Metal and Nonmetal Tailings Disposal Information Circular 8755 Design Guide for Metal and Nonmetal Tailings Disposal By Roy L. Soderberg and Richard A. Busch UNITED STATES DEPARTMENT OF THE INTERIOR Cecil D. Andrus, Secretary BUREAU OF MINES As the Nation's principal conservation agency, the Department of the Interim hos responsibility fu most of our nationally owned public lands ond natural resources. This includes fostering the wisest use of our land and water re- sources, protecting our fish and wildlife, preserving the environmental and cultural values of our national pork and histmica1 places, and pviding fa the enjoyment of life through outdou recreation. The Deprtment assesses our energy and mineral resources and works to assure that their development is in the best interests of all our people. The Department also has a major re- sponsibility fa American Indian reservation communities and fa people who live in Island Territaies under US. administration. This publication has been cataloged as follows: Soderberg, Roy L Design guide fm metal and nonmetal tailings disposal / by Roy L. Soderberg and Richard A. Busch. [Washington] : United States Depstment of the Interim, Bureau of Mines, 1977. 136 p. ; 27 cm. (Information circular - Bureau of Mines ; 8755) Bibliography: p. 107-111. 1. Tailings (Metallurgy). 2. Mineral industries - Wasre dis- posal. I. Busch, Richard k., joint author. 11. United Stares. Bureau of Mincs. UI. Title. IV. Series: United States. Bureau of Mincs. Information circular - Bureau of Mines ; 8755. TN23.U71 no. 8755 622.06173 U.S. Depr. of the Inr. Library For sale bp tbc Svpcriotcodcnt of DocumeoL1. USGwuoment prioting OMrr Wuhington. D.C. 20402 St& No. 024-001-0191)-8 CONTENTS Abstract .................................................................. Introduction ............................................................. Aclcnowledgments .......................................................... Background information ................................................... Tailings ponds ...................................................... Function of tailings ponds .......................................... Basic considerations..................................................... Daily tonnage ....................................................... Size of tailings area ............................................... Mill tailings ....................................................... Particle sizes ...................................................... Mine waste .......................................................... Leach dmps ......................................................... Site selection........................................................... Soils and construction material investigations ...................... Topography and geology .............................................. Climate and hydrology ............................................... Evaporation ......................................................... Runoff .............................................................. Subsurface exploration ................................................... Logging test holes .................................................. Sampling ............................................................ Laboratory testing .................................................. Grain-size distribution........................................ \ Specific gravity and.void ratlo ................................ Relative density ................................................ Plasticity ......................................................~ Compaction ..................................................... Shear strength ....: ............................................ Permeability ................................................... Consolidation tests ............................................ Field testing ......................................; ................ Standard penetration ........................................... Density ........................................................ Shear strength ................................................. Permeability ................................................... Design criteria .......................................................... Upstream method ..................................................... Downstream method ................................................... Centerline method ................................................... Upstream method with cyclones ....................................... Starter dam design .................................................. Pervious starter dam ........................................... Impervious starter dam ......................................... Drainage ............................................................ Drains .............................................................. Blanket drain .................................................. Pipe drain ..................................................... CONTENTS .-Continued Strip drain .................................................... Filters and transition zones ................................... Relief wells ................................................... Vertical sand drains ........................................... Rate of seepage ................................................ Surface runoff control .............................................. Initial construction ...................................................... Site preparation .................................................... Water reclaim system ................................................ Decant pipe and towers ......................................... Barge pumps .................................................... Siphons ........................................................ Comparison of the three systems ................................ Decant system ............................................. ~ ~ ~-... Barge pump system ......................................... Siphon reclaim system .................................... Starter dam construction ............................................ Fill compaction ..................................................... Construction durtng operation ............................................. Coarse sand and clean separation by spigoting ....................... Fine grind and poor separation by spigoting ......................... Sand yield .......................................................... Upstream construction with spigot sand .............................. Upstream construction with cyclones ................................. Downstream construction wlth cyclones ............................... Centerline method ................................................... Influences on design ................................................ Sand separation ..................................................... spigots ........................................................ Cyclones ....................................................... Pond water management ............................................... Embankment freeboard and wave protection ............................ Cores, blankets, and membranes ........................................... Sealing the bottom of tailings ponds ................................ Hydraulic barriers .................................................. Instrumentation .......................................................... Piezometers ......................................................... Movement indicators ................................................. Pressure cells ...................................................... Records ............................................................. Slope stability.......................................................... Safety factor ....................................................... Rotational slides ................................................... Computer allalysis ................................................... Computer input ...................................................... Maintenance and inspection ............................................... Seepage control in an operating pond ................................ Surface drainage control ............................................ iii Remedial measures ................................................... Surmnary .................................................................. Bibliography ............................................................. Appendix A.--Tailings pond evaporation ................................... Appendix B.--Estimating runoff ........................................... Appendix C.--Seepage and flow nets ................................................. Appendix D.--Slope stability analysis, simplified- . ~ Bishop method .......... Appendix E.--Nomenclature ................................................ Capacity-elevation-the curve ....................................... Screen analysis-- typical metal mine general mill tailings ........... Gradation of typical Florida phosphate slimes ....................... Increased density with depth ........................................ Typical log of exploration hole ..................................... Key for exploration logs ............................................ Mohr diagram ........................................................ Permeability coefficients for soils ................................. Gradation of metal mine tailings-- coarse grind. low pulp density, mine
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