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Methodology for a dump design optimization in large-scale open pit mines

Taylor & Francis
Cogent Engineering
Authors:

Abstract

Modern large-scale open pit mines move hundreds of thousands of tonnes of material daily, from the loading sources to the destination zones, whether these are massive mine dumps or, to a lesser extent, to the grinding mills. Mine dumps can be classified as leach or waste dumps, depending upon their economic viability to be processed in-place, a condition that has experienced great progress in the last decades and has reconfigured the open pit haulage network with an increase in the number of dumps. Therefore, new methods for dump design optimization are of the highest priority in mine planning management. This paper presents a methodology to model and optimize the design of a dump by minimizing the total haulage costs. The location and design of these dumps will be given mainly by the geological characteristics of the mineral, tonnage delivered, topographical conditions, infrastructure capital and transportation costs. Spatial and physical design possibilities, in addition, provide a set of parameters of mathematical and economic relationship that creates opportunities for modelling and thus facilitates the measurement and optimization of ultimate dump designs. The proposed methodology consists of: (1) Formulation of a dump model based on a system of equations relying on multiple relevant parameters; (2) Solves by minimizing the total cost using linear programming and determines a “preliminary” dump design; (3) Through a series of iterations, changes the “preliminary” footprint by projecting it to the topography and creates the ultimate dump design. Finally, an application for a waste rock dump illustrates this methodology.
Puell Ortiz, Cogent Engineering (2017),
4: 1387955
https://doi.org/10.1080/23311916.2017.1387955
CIVIL & ENVIRONMENTAL ENGINEERING | RESEARCH ARTICLE
Methodology for a dump design optimization in
large-scale open pit mines
Jorge Puell Ortiz
1
*
Abstract:Modern large-scale open pit mines move hundreds of thousands of tonnes
of material daily, from the loading sources to the destination zones, whether these are
massive mine dumps or, to a lesser extent, to the grinding mills. Mine dumps can be
classified as leach or waste dumps, depending upon their economic viability to be pro-
cessed in-place, a condition that has experienced great progress in the last decades
and has reconfigured the open pit haulage network with an increase in the number
of dumps. Therefore, new methods for dump design optimization are of the highest
priority in mine planning management. This paper presents a methodology to model
and optimize the design of a dump by minimizing the total haulage costs. The loca-
tion and design of these dumps will be given mainly by the geological characteristics
of the mineral, tonnage delivered, topographical conditions, infrastructure capital and
transportation costs. Spatial and physical design possibilities, in addition, provide a
set of parameters of mathematical and economic relationship that creates opportuni-
ties for modelling and thus facilitates the measurement and optimization of ultimate
dump designs. The proposed methodology consists of: (1) Formulation of a dump
model based on a system of equations relying on multiple relevant parameters; (2)
Solves by minimizing the total cost using linear programming and determines a “pre-
liminary” dump design; (3) Through a series of iterations, changes the “preliminary”
*Corresponding author: Jorge Puell Ortiz,
Department of Mining and Geological
Engineering, University of Arizona,
Tucson, USA
E-mail: jpuell@email.arizona.edu
Reviewing editor:
Sanjay Kumar Shukla, Edith Cowan
University, Australia
Additional information is available at
the end of the article
ABOUT THE AUTHOR
Jorge Puell Ortiz received MSc degree in Mining
Engineering from Colorado School of Mines,
USA. Mr Jorge Puell Ortiz is a PhD student at the
University of Arizona, Tucson, USA. He worked
principally in the field of open pit & underground
mines, mine projects, mine planning, operations
supervisor, consulting and project management
for Freeport-McMoRan Copper & Gold, Xstrata plc,
BHP Billiton and Newmont. His research interest
emphasize on: Mine/Stockpile planning and
design, simulation, mine water management,
leaching technologies, GPS monitoring, sensors,
radars and laser measuring techniques. He is a
certified professional engineer (PE) for the State of
Arizona and also a certified Project Management
Professional (PMP).
PUBLIC INTEREST STATEMENT
Mine dumps can be classified as leach or waste
dumps, depending upon their economic viability
to be processed in-place, a condition that has
experienced great progress in the last decades and
has allowed large-scale surfaces mines to build
larger and higher dumps, As a result, the entire
mine configuration has changed, bringing with it
concerns on safety and the environment, although
at the same time it creates opportunities for
optimization. Therefore, new methods for dump
design optimization are of the highest priority in
mine planning management. This paper presents
a methodology to model and optimize the design
of a mine dump by minimizing the total haulage
costs. The proposed methodology consists of:
(1) formulation of a dump model; (2) solves by
using linear programming and determines a
“preliminary” dump design; (3) through a series of
iterations, changes the “preliminary” footprint and
creates the ultimate dump design.
Received: 10 May 2017
Accepted: 30 September 2017
First Published: 05 October 2017
© 2017 The Author(s). This open access article is distributed under a Creative Commons Attribution
(CC-BY) 4.0 license.
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Puell Ortiz, Cogent Engineering (2017),
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footprint by projecting it to the topography and creates the ultimate dump design.
Finally, an application for a waste rock dump illustrates this methodology.
Subjects: Engineering Project Management; Mining Engineering; Planning & Design;
Sustainable Mining
Keywords: mine planning; dump design; open pit; optimization
1. Introduction
Three major destination groups, characterized by a cut-o grade criteria and ore type, represent the
places in the mine where the material receives specific treatment after its delivery from the pit:
leach dumps, waste dumps and mill (Hustrulid, Kuchta, & Martin, 2013). Dump leaching facilities are
built to receive and treat low-grade ore by the use of solution agents, while waste rock dumps store
uneconomic material. Dump leaching technologies have developed over the last decades, allowing
the mining industry to build larger and higher dumps faster than ever (Smith, 2002), since they have
proven to be an ecient method of treating oxide and sulfide ores, an attractive way to treat large
low-grade deposits (Dorey, Van Zyl, & Kiel, 1988). As a result, an increase in the number of dumps,
which are the most visual landforms left after mining (Hekmat, Osanloo, & Shirazi, 2008) has recon-
figured the open pit mines network organization and landscape.
Contributions to this progress have come from the mineral and metallurgical processing field (hy-
drometallurgy), geo-synthetics, slope stability, and best construction practices of solution collection
systems, notably prompted by environmental requirements. Researchers and slope stability practi-
tioners have achieved extensive progress and expertise in the areas of geotechnical engineering
(Ureel, 2014), establishing that a thorough knowledge of factors aecting the dump stability must
be properly considered at the design stage (Upadhyay, Sharma, & Singh, 1990); especially the floor
dip and foundation strength, from which the dump stability is highly sensitive (Rosengren, Simmons,
Maconochie, & Sullivan, 2010). Along with the geotechnical, several other attributes, such as the
topography, final pit limit, haul road distances, landform, among others, have been ranked, subjec-
tively and objectively, by multi-criteria decision methods with the specific aim of selecting the dump
location (Hekmat et al., 2008). However, few studies have attempted to integrate the safety and
environmental factors with the haulage costs in order to elaborate a strategic plan for the location
and ultimate dump design, whether it is leachable or for waste. The general practice for a dump
design consists on the availability principle (Li, Topal, & Williams, 2013) driven by the short-term
planning needs to make production by seeking the shortest haul to the dump, although this ap-
proach can be detrimental to the long-term scheduling and dump development.
In large-scale open pit mines, the mining process is rather complex and often involves dierent
run-of-mine (ROM) ore and waste material treatment downstream. Appropriate areas to place these
large amounts of material are limited and their selection and design must serve the environmental
factors and economic goals of the long-term mine plans. Normally, construction of the leach or
waste dumps results by creating a footprint base via deep dumping and subsequently, ramping up a
determined lift height to accumulate the ex-pit material.
In designing the dump, there are many ways to assign values and combine the dierent geomet-
ric and size parameters while respecting the safety and environmental constraints. The total ton-
nage capacity required can have as many geometrical representations as its limitations allow. In
this situation, building a mathematical optimization model is the best option to interrelate certain
key variables and the first approach to calculating the values that seek to maximize the satisfaction
of a linear programming objective. As most of the dumps are emplaced on irregular topographies, a
second approach has to contrast the values got by the generalized model and correct them, if neces-
sary, by a series of successive iterations and projections to the field.
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This paper presents a methodology to optimize the ultimate dump design in a mining operation by
minimizing the unit haulage cost using a linear algorithm and subsequent iterations on variables such
as the footprint base, number of lifts and haulage distances from the toe of the ramp to the dynamic
dumping point. Figure 1 briefly illustrates the process. This methodology applies to dumps receiving a
single material target as it is usual in large-scale open pit mines; hence, there is no need for any spe-
cial material blending or encapsulation, as the models proposed to handle waste rock dumping caus-
ing acid mine drainage (Li et al., 2013). In addition, an example illustrates the methodology.
2. Dump design considerations
A mine dump can be defined as a massive structure formed by placing large amounts of material in
lifts of a restricted vertical expansion that laid one on top of each other and form a stable slope at
the angle of repose. A dump so formed, however, needs a horizontal base at first, which is built by
push dumping material from a certain elevation and levelling o the required footprint area.
Generally, this first phase of the dump construction takes the irregular shape of the topography
where is placed. Subsequent lift height is constant, though is restricted to prevent shear stresses on
the foundation and is a factor to control consolidations and permeability variations (Zanbak, 2012).
The total height of the dump is also restricted by formation mechanism (Zhang et al., 2014) and car-
rying capacity limitations (Peng, Ji, Zhao, & Ren, 2013). As in most of the large open pit operations,
haulage is performed by heavy trucks, the access to the successive dump lifts is achieved by estab-
lishing ramps of a suitable width, super elevation and gradient in order to minimize travel distance
and therefore to reduce haulage costs (Figure 2).
In dump designing, costs may be governed by any or all of the following factors:
Geometry: Usually designed to handle a total capacity throughout the life-of-mine. Over-
dimensioning can cause underutilization of valuable areas. Under dimensioning can result in the
increase of the total haulage distances.
Operating costs: Costs resulting from fuel, energy, maintenance and labour of the haul trucks.
Haulage distances: Minimizing the total haulage distance while meeting the required capacity
by strategic placing of the ramps, exits, entrances and dumping sequence.
Stability control: It will define the angle of repose and the nature of the underlying material.
Maintaining the stability of the dump may require relocation of weathered rock or material
blending, especially if water is present (Russell, 2008).
If it is a dump leach, a leaching cycle time will define the mining delivery rate and dumping
schedule. Ideally, deliveries rate from the mine should match the leaching cycle times of the
dump. Otherwise, there is a risk of short cycling and losing on mineral recoveries. In addition,
costs of building the leaching facilities are factored in (Kappes, 2002).
Acquisition of the land permit for dumping purposes as specified by law.
Environmental factors: costs of implementing and maintaining eective systems to reduce and
eliminate loses and contamination. Design considerations for reclamation and closure to maintain
long-term stability, erosion control (Piteau Associates Engineering Ltd, 1991) and to avoid
re-handling costs (Sommerville & Heyes, 2009).
Figure 1. Schematic flowchart
of the dump design process.
Yes
No
Identify Available
Area LP Model
Minimize
Costs
Design
Iterations
(Base area
variable)
Does it
Measured
Parameters Evaluate Options
Final Dump
meet tonnage?
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Although every dump is unique (Zástěrová et al., 2015) and some of its cost maybe be given by its
own factors, the above description includes all the general concerns one would have to elaborate
the most economical dump design.
3. Linear programming (LP) formulation of the dump model
Formulation of a model where the cost is to be minimized while meeting all the other constraints can
be achieved by using Linear Programming (LP). The method optimizes an outcome, such as the low-
est cost, in a mathematical model whose requirements are related by linear equations. Linear
Programming, as one of the most widely used operations research tools (Wright, 1996), has been
largely applied in the mining industry to solve production scheduling problems (Newman, Rubio,
Caro, Weintraub, & Kelly, 2010). Then a solver software (AMPL) will produce optimization problems
from models and data and will retrieve results for analysis (Figure 3).
The model is expressed as follows.
3.1. Sets
Ln
i
= Set of the number of lifts of the dump from lift i to lift n.
3.2. Objective function
The objective is to minimize dumping costs of the open pit operation by finding the shortest haulage
distances for the haul trucks in two round trips: (1) travel along the ramp and (2) travel the flat sur-
face from the crest of the ramp to the lift centroid. Such distances are multiplied by the operating
Figure 2. Typical configuration
of a mine dump.
Figure 3. Terminology for the LP
dump model.
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cost and tonnage dumped at that lift and then divided by the average speeds and haul truck
capacity.
where Ti = tonnage dumped at lift i; Ri is the distance of the ramp for lift i from toe to crest; Di is the
flat distance from the crest to the lift centroid; Si and SLi are the average speed up/down hill and at
flat surface, respectively; Ci and TC are the operating cost and capacity of the standard haul truck.
3.3. Constraints
3.3.1. The radius of the base of lift i
The generalized dump model is formulated within the context of making the most ecient theoreti-
cal dump and establishes a circular base which maximizes the use of the property surface and meets
the slope angle along its boundaries.
3.3.2. Ramp distance from toe to crest of lift i
where h = height of lift i and g is the grade (%) of the ramp.
3.3.3. Distance from crest to the centroid of lift i
where
𝛼
= angle of repose.
The centroid is the best approximation to the average distance travelled by haul trucks until the
lift is fully filled as long as the material dumped has uniform density.
3.3.4. Volume of lift i
3.3.5. Tonnage of lift i
where TF = Tonnage factor m3/tonne of the broken rock.
3.3.6. Total tonnage required or stockpile capacity
where TT = Total tonnage capacity required.
3.3.7. Non-negativity
(1)
Minimise
n
i(
Ti×Ri×Ci÷Si÷TC
)
+
n
i(
Ti×Di×Ci÷SLi÷TC
)
(2)
ri
0
(3)
R
i=h×i×
(
1
g
)
2
+
1
(4)
Di
=
ri;i
=
1
(5)
D
i=Di1
h
Tan (
𝛼
)
;i=2, ,
n
(6)
V
i=𝜋
(
r2
i+r2
i+1
)h
2
(7)
=
÷
(8)
n
i=0
Ti
TT
(9)
Ri,Di,Vi,Ti
0;
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4. Model implementation
4.1. Field input data
The proposed dump model concept has been applied to optimize the ultimate design of a waste
dump in an open pit copper mine. Mine production plan shows that the East pit will deploy uneco-
nomical waste material in an approximate amount of at least 515 million tonnes during its 15 years
life-of-mine operation. Land properties extend its limits on the East side over 6 Km2 of surface avail-
able. The results of the study will show the areas to conduct hydrological and hydraulic analyzes to
estimate precipitation, runos and the presence of aquifers. As the waste material deployed will
remain un-leached, its density and angle of repose will correspond to a broken and un-saturated
(dry) material. Table 1 presents an overview of the input parameters used for the dump model opti-
mization. Round-travel speeds are given by the technical specifications of the equivalent fleet truck
in route; and operating costs include maintenance, fuel consumption, and labor. Ramp grade and lift
height comply with the internal mine haul road design manual of the mine operation.
4.2. Linear programming coding and solving
Using AMPL (Fourer, Gay, & Kernighan, 2003) and CPLEX (2016) the model has been codified to solve
the objective function, variables, sets of inequalities and constraints. The data-set is accessed from
Microsoft Access. The program is executed on a computer of 2.80 GHz and 32 GB installed memory
RAM, and the results are displayed for base radius, the number of lifts, tonnes, volume, and dis-
tances. The optimal solution is found for a six lifts dump to optimize the objective function to a mini-
mum of $ 42,713,023.2. The result is presented for the total tonnage and costs-by lift, volume, and
summary of the ramp and flat travel distances. Table 2 shows the optimization output. It should be
noted that these results give us only a first idea of the total costs and values of the main variables.
The design is still subject to adjustments to be made during the engineering and construction phas-
es of the project. Likewise, be noted that the case studied does not include in its costs the use of
geomembranes to isolate the dump due to state regulations regarding waste overburden that was
not and will not be subject to leaching processes.
The value of the optimal base radius r (0) equal to 1,170 m. The ramp distance between the toe and
crest of every lift is 100.5 m (a berm of 0.5 m is left at every lift perimeter). A particularity of dumps is
that the haulage cost increases considerable from lift to lift (For instances, from lift 1 to lift 2, it in-
creases 12%) while the number of tonnes is reduced by only 2% for the same movement from lift 1
to lift 2. The sum of the accumulated total tonnes gets the minimal required capacity, but leaves the
dump open for further unplanned deliveries on top of the lift 6 level. Furthermore, the optimal radius
r (0) equal to 1,170 m is then compared with dierent cases of base radius values in order investigate
the eect of the number of lifts and base area on generated haulage costs as shown in Figure 4. The
∑Total cost curve indicates that a wide base dump area with less than four lifts yield more expensive
Table 1. Input parameters
aMinimum.
Parameter Details
Operating cost (of a truck) 280 $/h (operating, maintenance, labor and fuel)
Lift height 10 m
Speed uphill 17.7 km/h
Speed downhill 27.4 km/h
Speed level surface 45 km/h
Grade of ramp 10% gradient
Angle of repose 36.9°
Density – tonnage factor 0.467 m
3
/tonne
Total tonnage – capacity 515 Million Tonne
a
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plan scenarios. However, cost decreases when the number of lifts varies between five and seven.
After eight lifts and smaller base areas, the haulage cost increases gradually.
4.3. Iterative design process
Although linear programming optimizes the economic stockpile plan, it achieves this by assuming a
regular inward dump shape, but does nothing regarding the irregular topography to be filled in. A
process of iterative design overcomes this drawback through the use of calculated areas of interest,
prioritizing the base area found by the linear programming and building successive dump structures
until meeting the tonnage capacities. The first design 01 is framed inside a limited area—limit 01—
given by the optimum radius π * r2 (0) which equals 4,297,212 m2. Table 3 summarizes the main
characteristics of the three dump designs.
Figure 5 shows the three iterative limits. The innermost areas are reduced by eight percent while
retaining the same west side and horizontal axis. This gradual area reduction of eight percent is
done with the purpose of creating a design that best meets the required capacity. Here, the reduc-
tion has an equal percentage value, but it can also be variable, depending on whether the LP result
was over or underestimating. For the three limit areas, the west side and the horizontal axis are the
same to keep the shortest distance from the open pit exit. For operational convenience, property
limits have been made squared, although the dump design maintains smoothed boundaries.
Figure 4. Minimum costs
optimization results.
Table 2. Results for the optimal r (0)=1,170m
Lift number (i)R (i) (m) D (i) (m) V (i) (106×m3)T (i) (106×tonnes) Total cost (i)
(106×US$)
∑Total cost
(106×US$)
T (106×tonnes)
Lift 1 100.5 1,156.2 42.5 90.9 5.6 5.6 90.9
Lift 2 201.0 1,142.9 41.5 88.9 6.2 11.8 179.8
Lift 3 301.5 1,129.6 40.6 86.8 6.9 18.7 266.6
Lift 4 402.0 1,116.3 39.6 84.8 7.5 26.2 351.4
Lift 5 502.5 1,103.0 38.7 82.8 8.0 34.2 434.2
Lift 6 603.0 1,089.6 37.8 80.8 8.5 42.7 515.0
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The southern part of the dump is bounded by high elevated hill contours. The existing ground to-
pography will require subgrade preparation and fine over liner fill. Also, perimeter berms will be
constructed at each lift to prevent the runo of stormwater. Figures 68 represent the iterated de-
sign of the dumps 01, 02 and 03 respectively.
Table 3. A summary of the three dump designs
Dump 1 Dump 2 Dump 3
Side (m) 2,073 1,911 1,762
Base area (m
2
) 4,297,212 3,652,630 3,104,735
Side reduction (%) 0.92 0.92
Number lifts 6 6 7
Deep dump (10
6
× tonne) 272.9 267.7 238.4
Lift dump (10
6
× tonne) 265.5 247.9 262.2
Total dump (10
6
× tonne) 538.4 515.6 500.6
Figure 5. Three iteration limits
for dump design.
Figure 6. Dump design 01–6
lifts.
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Upon iteration of the design process, the total tonnage for each dump is calculated (see Table 3),
which determines that Dump 02 meets the required minimum capacity and is, therefore, the optimal
design in the economic and operational aspect. Dump 01 and Dump 03 are over and under dimen-
sioned and therefore are discarded as solutions. Notice that the base area calculated by the linear
programming output corresponds to Dump 01, but when projected against the topography increas-
es its tonnage capacity and makes it necessary to reduce the base area by eight percent to run the
next design option (Dump 02). The methodology ends with the third iteration that provides insu-
cient tonnage capacity.
5. Conclusions
Waste and leach dumps must be subjected to in-depth study from the start of the mining project
since they are among the most significant costs for the mine operation, and therefore their designs
must be properly located and optimized. Traditionally, dumps have been intuitively sized and placed
driven by short-term objectives, but this traditional approach, in the long term, results in under or
overutilization of the mine surface and longer distances traveled by haul trucks. The present article
outlines a method where a theoretical dump model is built based on geometrical and economic re-
lationships of its main parameters, an LP algorithm is formulated as an optimization problem where
Figure 7. Dump design 02–6
lifts.
Figure 8. Dump design 03–7
lifts.
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the objective function minimizes the total haulage costs and the base dump radio and lifts number
are defined as variables, solved and used to create alternative dump designs through successive it-
erations. Finally, the methodology compares and selects the ultimate dump design that best meets
the requirements. The proposed methodology diers from the traditional approach in its orientation
towards the economic value of the dierent combinations of the base area, lifts number and projec-
tion to the field that makes the optimal dump design.
This paper presented an application from an actual waste dump in an open pit copper mine. The
LP model is prepared to minimize haulage cost while handling a required tonnage capacity and
solved. Results showed that the larger the footprint base, the higher the haulage cost until the curve
reaches an inflection point (lowest cost) where the curvature changes. Afterwards, haulage cost in-
creases slightly if the footprint area is reduced. Proposed designs are built iteratively by reducing
eight percent the previous area until getting the ultimate dump design.
Funding
The author received no direct funding for this research.
Author details
Jorge Puell Ortiz
1
E-mail: jpuell@email.arizona.edu
ORCID ID: http://orcid.org/0000-0002-3442-9468
1
Department of Mining and Geological Engineering, University
of Arizona, Tucson, USA.
Citation information
Cite this article as: Methodology for a dump design
optimization in large-scale open pit mines, Jorge Puell
Ortiz, Cogent Engineering(2017), 4: 1387955.
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... Even some papers related to waste management include the word design in the title, they only partially address the actual overall design components and mostly focus only on the height of the waste dump or on the selection of the optimal one from a set of predefined dump designs based on economic, geotechnical or environmental conditions [34][35][36]. A particularly interesting study has been carried out by Ortiz [37], who uses linear programming to optimise waste dump design. More specifically, he optimises the ratio between the number of benches and the base area of the waste dump (more dump benches mean a smaller waste dump base area and vice versa) for a given volume, i.e., waste dump capacity. ...
... Despite the fact that the objective function defined in Equation (5) has a unique form adapted to the functionality of the model, it is based on earlier research [11,18,37,64] on the influencing factors and the importance of cost minimisation in the formation of waste dumps. ...
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Waste management is an unavoidable technological operation in the process of raw material extraction. The main characteristic of this technological operation is the handling of large quantities of waste material, which can amount to several hundred million cubic metres. At the same time, this operation must comply with all administrative and environmental standards. Therefore, optimising waste rock management (particularly haulage and dumping) has the potential to significantly improve the overall value of the project. This paper presents a hybrid model for the optimisation of waste dump design and site selection. The model is based on different mathematical methods (Monte Carlo simulation, genetic algorithm, analytic hierarchy process and heuristic methods) adapted to different aspects of the problem. The main objective of the model is to provide a solution (in analytical and graphical form) for the draft waste dump design, on the basis of which the final waste dump design can be defined. The functioning of the model is verified using an example of an existing open pit. In the case study, 2250 members of the initial population (different waste dump variants) were generated, and a total of 110 optimised solutions were obtained using 15 optimisations. The solution with the best value of the objective function is adopted, and the final waste dump design is created.
... Particularly, mined land closure and reclamation is a crucial phase of any mining project, and it should be carried out following green mining policies once mining activities cease (Zhou et al., 2020;Samadi et al., 2023). Neglecting any aspect of sustainable development in mine waste management can have severe consequences (Ortiz and Shukla, 2017). It is therefore important to adopt sustainable mine waste management that aims to minimize the volume of waste sent to external dumps for mitigating the adverse environmental, social, and economic impacts. ...
... Li et al. (2014) expanded upon their previous model by incorporating the minimization of hauling distance and optimization of trucks' allocation. Ortiz and Shukla (2017) developed a linear programming model to minimize the total cost of waste hauling and optimize dump design. Fu et al. (2018) developed an MIP-based model that incorporates the optimization of waste dumping and ore production scheduling to maximize net present value. ...
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... In addition to high costs, the sanation of a damaged dump also includes a risk assessment in mining project realization, in real time. For a long period of time, many authors around the world have been paying great attention to the analysis and minimization of dump slide risks in the mining design phase with a presentation of many necessary sanation possibilities, and a lot of research has been carried out in this area [4,5,7,8,9,12]. The use of the proposed risk evaluation methodology for analyzing the opencast internal dump sanation risks in the design phase stage includes defining the influence of economic, technical, ecological and geotechnical parameters and appropriate failure consequence costs in accordance with the Life Cycle risk management approach and standard ISO 31000:2018 [1,2,6,10,11]. In addition to sanation costs, internal dump sanation process includes the highest cost of production losses with the postponement of the project implementation deadline [3,10]. ...
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... Как правило, сплошные системы разработки с внутренним отвалообразованием применяются при горизонтальном или пологом залегании месторождения с коэффициентом заполняемости выработанного пространства (К з ) равным 1, при котором выработанное пространство полностью заполняется вскрышными породами. При этом в основном используются сплошные и углубочно-сплошные системы разработки с поперечным и продольным размещением фронта горных работ, которые обеспечивают землесберегающий способ разработки месторождения [9][10][11][12]. Как показала практика, данная технология значительно повышает эффективность открытой угледобычи и максимально снижает экологическую нагрузку на окружающую среду. ...
... Badiozamani and Askari-Nasab (2016) provided an MIP model considering waste dump capacity and reclamation strategies to increase NPV, reduce the tonnage of waste at the dump, and lower the dump reclamation cost. Ortiz and Shukla (2017) developed a linear programming model for waste dump design to reduce overall waste rock haulage cost. Rimélé et al. (2018) developed a stochastic programming model to optimize SWRD in open-pit mines, emphasizing the fulfillment of environmental requirements in mining operations. ...
... Even some papers related to waste management include the word design in the title, they only partially address the actual overall design components and mostly focus only on the height of the waste dump or on the selection of the optimal one from a set of predefined dump designs based on economic, geotechnical or environmental conditions [29][30][31]. A particularly interesting study has been carried out by Ortiz [32], who uses linear programming to optimise waste dump design. More specifically, he optimises the ratio between the number of benches and the base area of the waste dump (more dump benches mean a smaller waste dump base area and vice versa) for a given volume, i.e. waste dump capacity. ...
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Waste management is an unavoidable technological operation in the process of raw material extraction. The main characteristic of this technological operation is the handling of large quantities of waste material, which can amount to several hundred million cubic metres. Working with this amount of material usually requires high-capacity systems for excavation and loading, a large fleet of trucks for haulage, construction, and maintenance of a complex roads network, use of a significant area of land in order to achieve the required capacities, etc. At the same time, this operation must comply with all administrative and environmental standards. Therefore, optimising waste rock management (particularly haulage and dumping) has the potential to significantly improve the overall value of the project. This paper presents a hybrid model for the optimisation of waste dump design and site selection. The model is based on different mathematical methods (genetic algorithm, analytic hierarchy process and heuristic methods) adapted to different aspects of the problem. The main objective of the model is to provide a solution (in analytical and graphical form) for the draft waste dump design, on the basis of which the final waste dump design can be defined.
... This leads to several benefits -no additional forested or fertile areas have to disturbed, as well as no further reclamation activities have to be made. From an economic point of view, waste dumping depends mostly on the distance of the dump from the open-pit mine and therefore an optimisation problem must be solved for the transportation costs (Ortiz, 2017). ...
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The location for dumping the waste from the open-pit mine has a significant weight for the establishment of the waste treatment costs. According to the constructive parameters of the waste dump and the terrain’s characteristics, the volume of the affected area is determined, in relation to the waste volume generated from the exploitation of a mineral deposit. In order to optimise the waste dump’s location and its constructive parameters, a number of alternatives have to be taken into account. These alternatives have to be technically plausible, as well as their safety factor must be satisfactory. Based on the considered alternatives, the optimisation problem can be defined so that the optimal solution provides the required capacity of the waste dump, as well as a minimal area of negative environmental impact and lowest operational costs.
... (3) Planificar los tratamientos para el jal La planificación es un aspecto fundamental en cada parte de la restauración. Tanto si se trata de la forma del depósito de jales o relaves mineros (Hustrulid et al., 2013;Puell Ortiz, 2017), hasta la aplicación de cada estrategia de mitigación como la remediación, la rehabilitación o la restauración; estas deben ir precedidas de una planificación (Fig. 5). Así mismo, debe existir una planificación de las técnicas de rehabilitación tanto a escala de paisaje (Buczyñska, 2020), como a escala local (Vick, 1990). ...
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Applications of operations research to mine planning date back to the 1960s. Since that time, optimization and simulation, in particular, have been applied to both surface and underground mine planning problems, including mine design, long-and short-term production scheduling, equipment selection, and dispatching, inter alia.In this paper, we review several decades of such literature with a particular emphasis on more recent work, suggestions for emerging areas, and highlights of successful industry applications.