7
Finally, it is important to note the evolution of the data
acquisition component of the rockfall testing program. At
the start of the project, NIOSH researchers manually flew
the DJI Phantom 4 Pro Drone to acquire the photos with
exceeding overlap for photogrammetry model development
which took a significant amount of time during rockfall
testing, especially when drone flights took place for each
size set. To better refine the drone flight process, NIOSH
researchers collaborated with Call &Nicholas, Inc. to build
flight plans specific to each testing scenario and carry out
the flights using the Lichi flight control application. These
flights along with surveyed control points helped in build-
ing photogrammetry models with known resolution as well
as cutting down time spent flying the drone between sets
of rockfall testing. With regards to use of the FLIR T620
Thermal Camera, NIOSH researchers have worked closely
with the GCE to ensure they are acquiring thermal videos
that enhance their research to detect and monitor rock-
fall events using that specific technology. At the start of
the project, NIOSH researchers operated the FLIR T620
under remote guidance from the GCE. Since 2022, a
member of the GCE has joined the NIOSH team during
each rockfall testing trip to operate the FLIR T620. More
recently, during the 2023 field season, along with continu-
ing operation of the FLIR T620, members of the GCE
tested the operation of a new standalone thermal camera
system which will be used to further advance detection and
alerting capabilities.
CONCLUSIONS
The overall success of the NIOSH rockfall testing program
lies in the support from the mining industry, specifically
the collaborating mine staff and partners to the Highwall
Safety project. The program will continue to evolve as test-
ing commences at additional mining properties to better
streamline each of its individual components. The goal is to
acquire empirical data that helps quantify the performance
of available criterion for rockfall catchment bench design in
a variety of bench configurations and optimizes said crite-
rion based on field calibration. While the NIOSH research
team will collect as much data as possible throughout the
duration of the Highwall Safety project (ending in 2026),
it is the hope that individual mine sites can take the frame-
work and lessons learned from the described rockfall test-
ing program to gather empirical data specific to their bench
configurations. Overall, the goals and activities associated
with this study and the NIOSH Highwall Safety project
are all designed for the betterment and improved safety of
open-pit mining projects worldwide.
DECLARATION OF COMPETING
INTEREST
The authors declare that they have no known competing
financial interests or personal relationships that could have
appeared to influence the work reported in this paper.
DISCLAIMER
The findings and conclusions in this report are those of
the author(s) and do not necessarily represent the official
position of the National Institute for Occupational Safety
and Health, Centers for Disease Control and Prevention.
Mention of any company or product does not constitute
endorsement by NIOSH.
REFERENCES
[1] C.-Y. Ku, “Assessing Rockfall Hazards Using a Three-
Dimensional Numerical Model Based on High
Resolution DEM,” in International Offshore and Polar
Engineering Conference, Rhodes, Greece, June 17–22
2012.
[2] C. Audige et al., “Monitoring requirements, limita-
tions and applications,” in Guidelines for slope perfor-
mance monitoring, R. Sharon and E. Eberhardt Eds.
Clayton, Australia: CSIRO, 2020.
[3] L. Lorig, P. Stacey, and J. Read, “Slope design meth-
ods,” in Guidelines for open pit slope design, J. Read
and P. Stacey Eds. Collingwood, Australia: CSIRO,
2009, ch. 10, pp. 237–263.
[4] T. Ryan and P. Pryor, “Designing catch benches and
interramp slopes,” in Slope Stability in Surface Mining,
W. Hustrulid, M. McCarter, and D. Van Zyl Eds.
Littleton, CO: Society for Mining, Metallurgy, and
Exploration, 2000, ch. 3.
[5] J. Mattern, “Using slope design fundamentals and
technology for slope steeping on a final wall at the
Goldstrike openpit,” Mining Engineering, vol. 2019,
no. February, 2019.
[6] A. Story, “Design optimization of safety benches for
surface quarries through rockfall testing and evalu-
ation,” Mining Engineering M.S. thesis, Virginia
Polytechnic Institute and State University, Blacksburg,
VA, 2010.
[7] M. Veillette, N. Rose, and M. King. (2019) Slope
steepening investigations for the Valley Pit at the Teck
Highland Valley copper mine using presplit blasting.
Min Eng. 16–30.
Finally, it is important to note the evolution of the data
acquisition component of the rockfall testing program. At
the start of the project, NIOSH researchers manually flew
the DJI Phantom 4 Pro Drone to acquire the photos with
exceeding overlap for photogrammetry model development
which took a significant amount of time during rockfall
testing, especially when drone flights took place for each
size set. To better refine the drone flight process, NIOSH
researchers collaborated with Call &Nicholas, Inc. to build
flight plans specific to each testing scenario and carry out
the flights using the Lichi flight control application. These
flights along with surveyed control points helped in build-
ing photogrammetry models with known resolution as well
as cutting down time spent flying the drone between sets
of rockfall testing. With regards to use of the FLIR T620
Thermal Camera, NIOSH researchers have worked closely
with the GCE to ensure they are acquiring thermal videos
that enhance their research to detect and monitor rock-
fall events using that specific technology. At the start of
the project, NIOSH researchers operated the FLIR T620
under remote guidance from the GCE. Since 2022, a
member of the GCE has joined the NIOSH team during
each rockfall testing trip to operate the FLIR T620. More
recently, during the 2023 field season, along with continu-
ing operation of the FLIR T620, members of the GCE
tested the operation of a new standalone thermal camera
system which will be used to further advance detection and
alerting capabilities.
CONCLUSIONS
The overall success of the NIOSH rockfall testing program
lies in the support from the mining industry, specifically
the collaborating mine staff and partners to the Highwall
Safety project. The program will continue to evolve as test-
ing commences at additional mining properties to better
streamline each of its individual components. The goal is to
acquire empirical data that helps quantify the performance
of available criterion for rockfall catchment bench design in
a variety of bench configurations and optimizes said crite-
rion based on field calibration. While the NIOSH research
team will collect as much data as possible throughout the
duration of the Highwall Safety project (ending in 2026),
it is the hope that individual mine sites can take the frame-
work and lessons learned from the described rockfall test-
ing program to gather empirical data specific to their bench
configurations. Overall, the goals and activities associated
with this study and the NIOSH Highwall Safety project
are all designed for the betterment and improved safety of
open-pit mining projects worldwide.
DECLARATION OF COMPETING
INTEREST
The authors declare that they have no known competing
financial interests or personal relationships that could have
appeared to influence the work reported in this paper.
DISCLAIMER
The findings and conclusions in this report are those of
the author(s) and do not necessarily represent the official
position of the National Institute for Occupational Safety
and Health, Centers for Disease Control and Prevention.
Mention of any company or product does not constitute
endorsement by NIOSH.
REFERENCES
[1] C.-Y. Ku, “Assessing Rockfall Hazards Using a Three-
Dimensional Numerical Model Based on High
Resolution DEM,” in International Offshore and Polar
Engineering Conference, Rhodes, Greece, June 17–22
2012.
[2] C. Audige et al., “Monitoring requirements, limita-
tions and applications,” in Guidelines for slope perfor-
mance monitoring, R. Sharon and E. Eberhardt Eds.
Clayton, Australia: CSIRO, 2020.
[3] L. Lorig, P. Stacey, and J. Read, “Slope design meth-
ods,” in Guidelines for open pit slope design, J. Read
and P. Stacey Eds. Collingwood, Australia: CSIRO,
2009, ch. 10, pp. 237–263.
[4] T. Ryan and P. Pryor, “Designing catch benches and
interramp slopes,” in Slope Stability in Surface Mining,
W. Hustrulid, M. McCarter, and D. Van Zyl Eds.
Littleton, CO: Society for Mining, Metallurgy, and
Exploration, 2000, ch. 3.
[5] J. Mattern, “Using slope design fundamentals and
technology for slope steeping on a final wall at the
Goldstrike openpit,” Mining Engineering, vol. 2019,
no. February, 2019.
[6] A. Story, “Design optimization of safety benches for
surface quarries through rockfall testing and evalu-
ation,” Mining Engineering M.S. thesis, Virginia
Polytechnic Institute and State University, Blacksburg,
VA, 2010.
[7] M. Veillette, N. Rose, and M. King. (2019) Slope
steepening investigations for the Valley Pit at the Teck
Highland Valley copper mine using presplit blasting.
Min Eng. 16–30.