1
24-001
A Case Study: Successfully Managing Excessive and
Rapid Slope Deformation in an Open Pit Mine
Utilizing Slope Monitoring Radar Systems
Justine Ealy
KGHM, Ruth, NV, USA
Christina Foster
KGHM, Ruth, NV, USA
Daniel Yang
Knight Piésold Ltd., Vancouver, Canada
ABSTRACT
Maintaining stable high walls can be a challenging task.
Complex geological and structural features, alteration
zones, rock mass properties, and hydrogeological condi-
tions must be well understood to design a safe mining envi-
ronment. Economic considerations must also be taken into
account as the mine operator must provide ore deliveries
and protect reserves. However, even when good engineer-
ing practices are followed, and proper blasting and min-
ing techniques are implemented, slope movements may
still occur.
When these slope instabilities are minor, the mine is
often able to continue operations with minimal impacts
on safety or production. When these occurrences are exces-
sive and coupled with high rates of movement, a robust
monitoring system is crucial to continuing mining activi-
ties while protecting personnel.
This paper summarizes the approach an open pit mine
in Nevada took as excessive and rapid high-wall move-
ment was experienced in an integral area. Creative min-
ing approaches, combined with slope monitoring radar
technology, were utilized to maintain safe and successful
mining activities despite active movement that exceeded an
average velocity of 30 inches per day.
INTRODUCTION
The mine is located in eastern Nevada, and is a complex
copper porphyry deposit. The location has been intermit-
tently mined since the late 1800s, with the current company
operating the site since the mid-2000s. The property com-
prises several open pits, at various stages of operation and
closure that are mined by the conventional method of blast-
ing and truck haulage to a processing plant (Yang, 2016).
One of the open pits on the property experienced sig-
nificant and constant high-wall instabilities on the North,
East, and South highwalls from 2013 to 2020. During this
six-and-a-half-year period, observational methods, ter-
restrial radar monitoring, and responsive creative mining
approaches allowed the mine to successfully extract approx-
imately 80 million additional contained pounds of copper
from the pit beyond what was planned.
GEOLOGICAL AND GROUNDWATER
BACKGROUND
The mine is developed in a structurally complex porphyry
copper deposit. Following the main stages of copper min-
eralization, the quartz monzonite porphyry crystallized and
was affected by meteoric water resulting in pervasive argil-
lization. The rock mass was fragmented by normal faulting
24-001
A Case Study: Successfully Managing Excessive and
Rapid Slope Deformation in an Open Pit Mine
Utilizing Slope Monitoring Radar Systems
Justine Ealy
KGHM, Ruth, NV, USA
Christina Foster
KGHM, Ruth, NV, USA
Daniel Yang
Knight Piésold Ltd., Vancouver, Canada
ABSTRACT
Maintaining stable high walls can be a challenging task.
Complex geological and structural features, alteration
zones, rock mass properties, and hydrogeological condi-
tions must be well understood to design a safe mining envi-
ronment. Economic considerations must also be taken into
account as the mine operator must provide ore deliveries
and protect reserves. However, even when good engineer-
ing practices are followed, and proper blasting and min-
ing techniques are implemented, slope movements may
still occur.
When these slope instabilities are minor, the mine is
often able to continue operations with minimal impacts
on safety or production. When these occurrences are exces-
sive and coupled with high rates of movement, a robust
monitoring system is crucial to continuing mining activi-
ties while protecting personnel.
This paper summarizes the approach an open pit mine
in Nevada took as excessive and rapid high-wall move-
ment was experienced in an integral area. Creative min-
ing approaches, combined with slope monitoring radar
technology, were utilized to maintain safe and successful
mining activities despite active movement that exceeded an
average velocity of 30 inches per day.
INTRODUCTION
The mine is located in eastern Nevada, and is a complex
copper porphyry deposit. The location has been intermit-
tently mined since the late 1800s, with the current company
operating the site since the mid-2000s. The property com-
prises several open pits, at various stages of operation and
closure that are mined by the conventional method of blast-
ing and truck haulage to a processing plant (Yang, 2016).
One of the open pits on the property experienced sig-
nificant and constant high-wall instabilities on the North,
East, and South highwalls from 2013 to 2020. During this
six-and-a-half-year period, observational methods, ter-
restrial radar monitoring, and responsive creative mining
approaches allowed the mine to successfully extract approx-
imately 80 million additional contained pounds of copper
from the pit beyond what was planned.
GEOLOGICAL AND GROUNDWATER
BACKGROUND
The mine is developed in a structurally complex porphyry
copper deposit. Following the main stages of copper min-
eralization, the quartz monzonite porphyry crystallized and
was affected by meteoric water resulting in pervasive argil-
lization. The rock mass was fragmented by normal faulting