Appendix C - Cultural Heritage Impact Assessment - Peabody Energy

These sites can potentially be affected by cracking of the surface soils as a result of mine subsidence
movements. It is unlikely, however, that the scattered artefacts or isolated finds themselves would be
impacted by surface cracking. It is possible, however, that if remediation of the surface was required
after mining, that these works could potentially impact these sites.
It is recommended that WCPL seek the required approvals from the appropriate authorities, in the
event that remediation of the surface is required in the locations of the artefact scatters and isolated
finds.
Further assessments of the potential impacts on the open sites are provided in a report by
RPS (2012).
6.14.5. Impact Assessments for the Scarred Tree
There is one scarred tree within the Study Area, being Wambo Site 360, which is located above the
chain pillar between the approved WMLW8 and the proposed WMLW9 in the Wambo Seam.
It has been found, from past longwall mining experience, that the incidence of impacts on trees is
extremely rare. Impacts on trees have only been previously observed where the depths of cover were
extremely shallow, in the order of 50 metres or less, or on very steeply sloping terrain, in the order of 1
in 1 or greater.
In the location of the scarred tree, the depths of cover are 125 metres to the existing workings in the
Whybrow Seam, 210 metres to the proposed longwalls in the Wambo Seam, 380 metres to the future
longwalls in the Arrowfield Seam, and 410 metres to the future longwalls in the Bowfield Seam. The
natural surface in this location is relatively flat, with the natural gradient being less than 1 in 3. It is
unlikely, therefore, that the scarred tree would be adversely impacted as a result of the extraction of
the proposed and future longwalls.
Large surface cracking or ground heaving could occur as a result of the multi-seam mining, which is
described in Section 4.7. The incidence of the larger surface deformations being coincident with the
scarred tree is considered low.
Further assessments of the potential impacts on the scarred tree are provided in a report by RPS
(2012).
6.14.6. Impact Assessments for the Archaeological Sites Based on Increased Predictions
If the actual mine subsidence at the archaeological sites exceeded those predicted by a factor of
2 times, the likelihoods and extents of cracking in the surface soils would also increase. It would still
be unlikely that the artefacts scatters or isolated finds themselves would be impacted by the surface
cracking and the methods of remediation, if required, would not be expected to change. It would also
be unlikely that the scarred tree would be impacted by the surface cracking, as mining induced
impacts have not been observed on trees in the NSW Coalfields where the depths of cover have been
greater than 50 metres, such as the case within the Study Area.
6.15. State Survey Control Marks
The locations and details of the state survey control marks were obtained from the Land and Property
Management Authority using the Six Viewer (2012). There were no state survey control marks
identified within or in the immediate vicinity of the Study Area. There were state survey control marks
identified further afield, outside the extents of Drawing No. MSEC495-12, which are located at
distances greater than 1.5 kilometres from the proposed longwalls.
The survey control marks located in the area could be affected by far-field horizontal movements, up
to 3 kilometres outside the extents of the proposed longwalls. Far-field horizontal movements and the
methods used to predict such movements are described further in Sections 4.5 and B.4.
It will be necessary on the completion of the longwalls, when the ground has stabilised, to re-establish
any survey control marks that are required for future use. Consultation between WCPL and the
Department of Lands will be required to ensure that these survey control marks are reinstated at the
appropriate time, as required.
SUBSIDENCE PREDICTIONS AND IMPACT ASSESSMENTS FOR NWUM WMLW9 AND WMLW10
© MSEC OCTOBER 2012 | REPORT NUMBER MSEC495 | REVISION C
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