The methodology followed in this research has made it possible to make contributions in the administrative, but mainly technical, field to define the negative impacts generated by wind erosion in a tailings deposit, information that can be used to define actions to be followed to minimize its impact. The research was carried out in a tailings dam in the Atacama Region, Chile that is in operation, within the framework of the development of the FONDEF D06I1097 project and the doctoral thesis “Measurement system of the stability of mining tailings deposits against the wind action, for its recovery as a sustainable urban space. The case of the city of Copiapo in Chile”, presented in 2016 at the Polytechnic University of Madrid, Spain .
Mining has been practiced in Chile for several centuries, which has contributed to the country’s progress. However, this activity constitutes a potential risk of affectation for people and the environment. Tailings require special attention to control the negative effects that wind erosion can cause. Wind erosion of the soil is a natural phenomenon; however, human activity has accelerated it, making it the main agricultural and environmental problem worldwide. On the other hand, according to JRI Engineering in the Mining Roadmap 2035  in 2015 around 1.7 million tons per day of tailings were produced and could reach 3 million tons per day in the next decade.
The data collected indicates that wind erosion associated with tailings deposits has not been extensively studied, mainly because the climatic and geographical conditions. high mining production and high number of tailings deposits that occur in the Chilean case, do not occur in other countries. realities with the same intensity, which justified the development of this research. In the Guide to Evaluate EIAs of Mining Projects, experts from the World Alliance for Environmental Law state that the transport of emissions in the air occurs during all stages of the life cycle of a mining operation, the waste piles or deposits contain small particles that can be easily dispersed by the wind. 
To define that a tailings deposit is being affected by wind erosion, it is usually enough to observe the place and determine if the wind raises dust or not, however, this is not enough to determine the magnitude of the problem and the measures that must be taken to reduce it, so it is necessary to evaluate the effects of wind erosion in a more objective way.
The objective of this research was to develop an in-situ measurement system that allows evaluating the emission of particulate matter into the environment due to the wind effect from Chilean mining waste deposits.
The methodology used in the development of this research includes different clearly established activities, such as background information collection, definition of the experimental methodology, development of the experimental research with the definition of the experimental field, execution of a test campaign and field measurements, data analysis and conclusions. The execution of the different experimental campaigns and the collection of more information in parallel, allowed improvements to be made to the methodology for evaluating wind erosion in tailings deposits, finally achieving the definitive version, corresponding to the result of this investigation. The investigationscarried out by Cristóbal García et al.  and Asunción Romero and Gregorio García, et al. , made it possible to demonstrate the difficulty of developing technologies to measure particles carried by the wind in tailings
deposits and stop I manifest the importance of developing
methodologies that allow studying the effects that wind erosion
has on different areas impacted by the dumping of mining waste,
in order to determine the possible impacts, mitigation measures,
definition of land use, among others. The mechanics of wind
erosion, understood as the event through which the removal of
surface material by wind action occurs, which causes an effect “in
situ” and others in surrounding regions, allowed to identify the
types of transport that can suffer the tailings particles when affected
by the wind, such as rolling, saltation and suspension (respirable
particles and settleable particles). This led to the identification
of parameters associated with the emission of particles in
different situations, concluding that indicators such as breathable
particulate matter, settleable particulate matter, saltation matter,
wind speed and direction, allow identifying and quantifying the
impacts produced by wind erosion in tailings deposits. With this
background, different techniques for measuring this phenomenon
were investigated and the application of each of them to tailings
deposits was analyzed, which allowed the design of integrated
tests for in situ evaluation of wind erosion in tailings deposits. Of
the investigated techniques, the measurement systems that were
used in the investigation contemplated:
I. Erosion pickets, which allow determining the variation of
the surface of the deposit affected by the wind, whether it suffers
loss or accumulation of tailings particles, over time. According to
the information collected, this technique had not been applied in
II. Measurement of breathable particulate matter, whose
objective is to determine the amount of breathable particles
with a diameter of 10 μm (PM10) and a diameter of 2.5 μm
(PM2.5), which are present in the tailings deposit at the time of
measurement. It is important to indicate that the technique for
measuring breathable particulate matter is normally a fixed piece
of equipment attached to a meteorological station, a situation that
in this case did not meet the requirements of measuring emission
at different points in the tailing dam and its periodicity, for which
reason it was investigated and a portable equipment that is used
to carry out measurements in work environments was identified.
According to the information collected, this technique had not
been applied in tailings deposits.
III. Direction and speed of the wind, the objective of these
measurements is to define where the prevailing wind comes
from and what speed it registers. Each time the determination
of breathable particulate matter is carried out, the direction and
speed of the wind must be determined at each measurement
point. According to the information collected, this technique had
not been applied in tailings deposits.
IV. Settleable particulate matter, its objective is to determine
the amount of settleable particulate matter that precipitates in
the tailings deposit. This measurement is carried out according
to the procedure established in the ASTM Standard. According to
the information collected, this technique had not been applied in
tailings deposits .
V. Matter in saltation (Leatherman traps, its objective is
to determine the amount of particles that the wind mobilizes by
saltation and drag on the surface using passive saltation traps,
or Leatherman traps. According to the bibliography, there is an
experience of its application in the Chilean tailings dam of the
Mantos Blancos mine located 45 km northeast of Antofagasta, but
no further information is available .
One of the main contributions of this research is the
adaptation of measurement techniques applied in other areas
such as agriculture, livestock, industrial, meteorological, and
urban to tailings deposits, developing an integrated wind erosion
measurement system, which incorporates different measurement
methods to quantify different aspects of wind erosion that affect
The experimental design raised the collection of information
that allows characterizing the study area and the geotechnical
characteristics of the tailings, subsequently testing different
measurement techniques and the periodicity of tests and
measurements. The methodology to characterize wind erosion
was developed based on experimental measurement campaigns
lasting approximately one year each, applying a dust-suppressing
treatment to four hectares of the deposit in operation, with the
purpose of controlling the emission of particulate matter and
evaluate its effectiveness by contrasting the measurements in
areas without treatment and with treatment.
The on-site evaluation was carried out in a tailings dam
located in the city of Copiapo, Chile, which is in the operating
stage, is very close to inhabited areas and at the beginning of the
investigation was being affected by the wind. Three experimental
campaigns were carried out, each lasting one year. The dust
suppressant treatment was carried out with magnesium chloride
in part of the sector affected by the action of the wind, leaving
the immediately adjoining areas without the application of this
suppressant. The campaigns carried out consider the application
of the dust suppressor in the January- February period and then
the evaluation of wind erosion during the rest of the year, until
the operation process deposits tailings again in the studied sector.
(Figure 1(a)) shows the location of the area evaluated during the
last measurement campaign carried out and the distribution of the
measurement points. The analysis of the results obtained in the
previous campaigns made it possible to optimize the evaluation,
considering five measurement points.
The measurement systems that were implemented, see
(Figure (1b)), were erosion pickets (C1 to C6 and at each of the
five measurement points, dust collectors, breathable particulate
matter, wind speed and direction, and traps by Leatherman.
(Figure 2) shows a typical monitoring station.
In the on-site evaluation tests in the tailings dam, the
application of the methodology has made it possible to measure
the effect of wind action on the tailings dam in operation and to
determine the performance of the tailings treated with a dust
suppressant, highlighting that the most direct techniques to
evaluate this situation are erosion picks and Leatherman traps.
However, all the applied techniques, to a greater or lesser extent,
show differences in the emission of particulate matter in the
tailings deposit between the area treated with dust suppressant
and untreated. From all the information generated in it, the
following particular conclusions can be obtained.
The results of the measurements of emissions of particulate
matter in saltation and rolling, carried out using Leatherman
traps, indicate that the traps located in the treated area collected
0.52% of the total material collected by all the traps located in
treated areas and untreated from the tailings dam, (Figure 3).
The dust suppression treatment implemented in the tailings
dam reduced the emission of particulate matter in saltation
and rolling to values greater than 99%, with respect to without
treatment, which was determined in all the campaigns in which
measurements were made with Leatherman traps. The suspended
settleable matter collector, located in the upper part of the treated
area, was the one that collected the least amount throughout
the measurement period compared to the other collectors, and
proportionally collected 12% of the total material collected in the
collectors of dust located in the treated and untreated area.
The dust suppression treatment implemented in tailings dam
reduced the emission of particulate matter in settleable suspension
to values higher than 85% with respect to the condition without
treatment, which was determined in all the campaigns in which
measurements were made with collectors of dust (Figures 4).
In relation to the measurement of breathable particulate
matter of 10 μm (PM10), the monitoring station located in the
upper part of the treated area was the one that recorded the least
amount during the entire measurement period compared to the
other two monitoring stations and proportionally captured 15%
of the total PM10 in the treated and untreated areas (Figure 5).
The analysis of the data has made it possible to define
variations in the emission of PM10 according to the time of year,
registering two periods of the year according to the wind speeds
measured, in the period from April to July the lowest wind speeds
are recorded and the lowest average emission of (PM10), in the
August-March period the highest wind speeds and the highest
average emission of (PM10) are recorded (Figure 6).
A variation of 141% has been determined in the average
emission of PM10 in the untreated area in the August-March period
compared to the April-July period, while in the treated area this
variation is 12%, although it registers an increase in the emission
of PM10, presents a smaller variation in the emission compared
to the period of lower wind speed, (Figure 7). This trend is also
observed in the breathable particulate matter of 2.5 μm.
The measurements carried out with the Dustmate equipment
have made it possible to demonstrate the effectiveness of the
measurement system, allowing the conclusion that the dust
suppression treatment implemented in the tailings dam reduces the emission of breathable suspended particulate matter to values greater than 80% with respect to the condition without treatment.
The analysis of the wind speed and direction measurements have
made it possible to make improvements in the operation of the
deposit and define the area to be treated with a dust suppressant
according seasons with to year, in order to minimize the emission
of particulate matter into the environment and other problems
associated with wind erosion, such as the stoppage of tailings
disposal as a result of dust clouds. The systems implemented
have made it possible to quantify the erosive process on the
surface of the tailings dam and have been able to demonstrate
the effectiveness of the dust suppressant in the treated areas in
relation to the situation without treatment.
Among the main conclusions of the research, it is highlighted
i. The experimental evaluations carried out in situ, within
the framework of this investigation, have allowed validating
the methodology to evaluate the emission of particulate matter
into the environment due to the effect of the wind from tailings
ii. Having this methodology makes it possible to better
solve the problem of wind erosion that affects tailings deposits.
The generated indicators are useful in the design process of
the recovery measures that are implemented and then in the
evaluation of their effectiveness.
iii. It is possible to affirm that compliance with the proposed
research methodology allowed achieving the stated objective,
since a measurement system was developed that allows evaluating
the emission of particulate matter into the environment due to the
wind effect from Chilean mining waste deposits.
iv. Among the results of scientific production, it is important
to highlight the officialization of the Chilean standard NCh 3266-
12 Tailings deposits - Characterization of the particulate matter
suppressor product - Evaluation of performance properties of
tailings treated with particulate matter suppressor, with which it
seeks to provide a tool for tailings deposit managers, supervisory
authorities, suppliers of dust suppressant products, among
others, that allows them to evaluate the effect of wind erosion on
tailings deposits and/or evaluate the effectiveness of the solutions
implemented to reduce their emissions .
Valenzuela P (2016) System for measuring the stability of mining tailings deposits against wind action, for their recovery as a sustainable urban space. The case of the city of Copiapo in Chile. Thesis to opt for the degree of doctor from the Polytechnic University of Madrid, Spain.
Kon L, Durucan S, Korre A (2004) Modeling of wind erosion and dust emission rates at mine tailing dams. Advances in Mineral Resources management ans environmental Geotechnology.
INN (2012) NCh 3266-2012 Tailings deposits – Characterization of the product suppressor of particulate matter – Evaluation of performance properties of treated tailings with suppressor of particulate matter.