HVO 2009 Annual Environmental Management Report - Final

Coal & Allied – Hunter Valley Operations
2.2.1 Vegetation Clearing
All cleared timber suitable for re-use as milling timber, fencing material or habitat reinstatement is
appropriately pushed up and cut as part of the timber removal and soil-stripping process. Prior to being used
for mining the vast majority of the site is selectively logged for use as fencing products. Additional unusable
timber is mulched for use on rehabilitation areas in order to retain moisture and nutrients and encourage seed
growth. While other remaining vegetative material is cut to size and either stored or relocated to rehabilitation
areas to provide habitat for fauna in accordance with Coal & Allied EMS Environmental Procedure 10.2 Fauna
and Flora.
Other remaining vegetative material which is unable to be used is cut to size and heaped, then pushed onto
the blasted ground and buried in the truck spoil. Vegetation removal ahead of mining is typically kept to within
two mining strips of the high wall, with provision for infrastructure and an access road located along the edge
of the strip area.
At HVO, native tree and shrub seed is harvested from areas within the mine lease and areas designated to be
cleared. During 2009 a Seed Strategy was developed for HVO and MTW to enhance species diversity and
creation of habitat on the areas of post-mining rehabilitation. There were two main components to developing
the Strategy: Part 1 – Review of the species mix to align with pre-mining communities and improve diversity
(particularly of understorey species); and Part 2 – Formalise the procedures for collecting and storing local
provenance native seed. The strategy will assist CNA to improve future native vegetation seed collection and
rehabilitation programmes.
2.2.2 Topsoil Management
Topsoil stripping and vegetation salvage is carried out in accordance with the relevant HVO MOP and Coal &
Allied EMS Environmental Procedure 5.1 Disturbance and Rehabilitation prior to the commencement of drill
and blast preparation. The depth of useful soil is identified on the topsoil stripping plan on a site-specific
basis, owing to the high variability in topsoil quality and depth. Topsoil is then used directly on new
rehabilitation areas wherever possible or stockpiled for re-use at various strategic locations around the mine
site and surveyed. The topsoil stockpiles and volumes are maintained by the Coal & Allied Environmental
Specialist Rehabilitation, as per the Coal & Allied EMS Environmental Procedure 5.1 Disturbance and
Rehabilitation.
2.3 CONSTRUCTION
The only additions or alterations to buildings or facilities during the 2009 reporting period were modifications
and additions to the Lemington Facilities.
2.4 MINING
HVO is organised into six mining zones; West, North, and Carrington Pits to the north of the Hunter River and
Riverview, Cheshunt and Lemington South Pits to the south of the Hunter River. The area to be mined is
geologically modelled, a plan is formed and the relevant mining locations are surveyed.
The area immediately preceding the active mining zone is stripped of topsoil, which is stockpiled for future
rehabilitation purposes or placed directly onto shaped areas where available.
To improve efficiency, overburden removal above the first seam and each subsequent layer of interburden is
drilled and blasted or ripped. Shovels, excavators and loaders remove the overburden/interburden, which is
transported by truck to be placed in previously worked areas of the mine. In addition to truck transportation,
draglines relocate large quantities of overburden/interburden within the pit. The top of each of the coal seams
is cleaned and prepared, then blasted or ripped and finally loaded by front-end loaders into haulage trucks.
Raw coal is transported to the Coal Preparation Plants (CPP) including the Hunter Valley CPP and Howick
CPP. The Newdell CPP is currently used only as a loading facility, whilst operations at the Lemington CPP
are currently suspended. The product coal is directly loaded at the Newdell or Hunter Valley Load Point
(HVLP) and railed to the Port of Newcastle for export. The coarse reject coal from the washing process is
trucked back into the active spoil emplacement areas for co-disposal with overburden.
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