Wambo Coal AEMR 2011-2012 - Peabody Energy

2011-2012 AEMR
only on ppv, WCPL engaged a specialist engineer
(Bill Jordan & Associates) to investigate whether
blast ground wave frequency, as well as ppv, is a
more accurate indicator of potential vibration
impacts. It has been previously been shown that
movement of the building or its parts can be greatly
amplified compared with the blast wave if resonant
frequencies are excited in the building.
Butchers Hut stabilisation
The results of this study will allow a better
appreciation of the risks posed to the Wambo
Homestead buildings from blast ground vibration,
and lead to more accurate setting of blast limits, and
blast design, which will take the resulting
frequencies into account.
As discussed in the last AEMR, a blast vibration
vulnerability study was completed during the
reporting period for the Wambo Homestead. For a
copy of the report please refer to Appendix 2E.
3.14 Spontaneous Combustion
3.14.1 Underground
Main Homestead stabilisation and stormwater
control
There were no spontaneous combustion incidents at
the Underground during the reporting period.
Inspections for spontaneous combustion form part
of the Underground inspection system. WCPL will
continue to monitor for signs of spontaneous
combustion in the next reporting period.
The Underground mine atmosphere is monitored
continuously in the main fan return. Monitoring
results and trends are displayed in the control room.
Any abnormal readings trigger an audible and visual
alarm. All monitoring equipment is tested and
calibrated regularly.
3.14.2 Open Cut
Carriage House & Stables stabilisation and
weather control
Blast Vibration Study
Wambo currently monitors and reports on open cut
blasting ground vibration, and potential impacts on
the WHC. Ground vibration is currently monitored
and assessed based on peak particle velocity (ppv),
measured in mm per second.
In response to concerns expressed about the
accuracy of assessing blast vibration impacts based
As reported in previous AEMR’s, spontaneous
combustion (spon comb activity within the Open Cut
operations is limited to one location. The spon comb
is located on the north western side of the Hunter
Pit. This incident is considered minor and is being
monitored by WCPL operations. Inspections for
spontaneous combustion form part of the Open Cut
inspection program.
3.14.3 CHPP
There were no spontaneous combustion incidents at
the CHPP during the reporting period. Inspections
for spontaneous combustion form part of the CHPP
inspection program.
Page 76