Tuesday, June 8, 2010

MINE DUMP DESIGN

Design for:
1. Safety
2. Environmental friendliness
3. Low construction and maintenance cost

What Dumps ?




Dump Design : Lifts



Dump Design
1. Constructed in lifts :
a. geotechnical consideration: stability
b. cost of haulage
c. ease of final grading
2. Slope the surface at two percent approx.
a. aid in run-off of water and drainage
b. dump volume increases at little cost
c. some additional safety afforded at backing-up
3. Control run-off water and drain recharge
4. Control dust
a. limit traffic, dust suppression

Dump Design : Lifts





Dump Design: Lift vs. Distance







Dump Lay-Out



Dump Construction





Dump Design : Lifts Note water control measures ….



Dump Location & Type





Material Placement Method



Dumps - cont (1)….
1. Dump settles:
* control by minimizing the rate of growth
* need to build-up the surface to maintain grades
2. Provide sufficient maintained space
* turning radiuses, 100 ft/vehicle crest
3. Provide light plants & dust suppression
4. Bulldozers/graders are needed
5. Care in dumping large boulders

Dumps- cont. (2)…..
1. How far to go?
* Land use defines required slope
* Dump to facilitate easy grading of the slope
2. When to reclaim?
* gradually, do not delay. WHY?
3. Monitoring is required
* surveying, extensometers, piezometers, inclinometers

Minimize rehandle!



Dump Problems
1. Slumping
* finer mat’l on top, often slumps
2. Liquefaction
* snowmelt or precipitation saturates dumps
* mud or debris flow may result
3. Foundation failure
* translation - decaying organics on slopes
* foundation spreading - squeezing ahead of the toe

Dump slope problems



Valley Fill Dump



Environmental Factors





Drainage Interception



How Are We Doing Here ?




Dump Related Legislation (Federal only)