WHITE ROCK QUARRY
White Rock Quarry
98 Horsnells Gully Road,
HORSNELL GULLY South Australia 5141
Australia
Telephone: (08) 8431 4866
Currently Approved Hours of Operation:
24 Hours, 7 Days Per Week
General Office Hours:
Monday – Friday: 6.30am – 5.00pm
Saturday: 6.30am – 12.00pm as required
INTRODUCTION
The Site has been highlighted by the State Government as a Strategic Resource Area (SRA). An SRA is an area within the greater Adelaide region, or near a regional centre that is of key economic value to South Australia due to the quantity or quality of construction materials or mineral resources that are extracted or contained within that area. The Site supports affordable local residential, commercial and infrastructure development in the Adelaide Metropolitan Area. It is a Hanson flagship site due to the proximity to the CBD of Adelaide and therefore a major infrastructure project.
Further information on Strategic Mineral Areas can be located here.
HISTORY
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The Ferraro family operated White Rock Quarries from approximately 1946, supplying aggregates to Metro Adelaide
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Pioneer Group of Companies procured land and Private Mine (PM) in approximately 1991
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Hanson procured the land and PM in 2007
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Operations at the quarry pre-date the introduction of the Mining Act 1971 (Mining Act)
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4 October 1973 the land was proclaimed as Private Mine (PM) 188
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A PM is a statutory right to extract minerals from land granted to those whose land titles enabled them to undertake mining and extractive operations and who were doing so, prior to 1971
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A PM is a right to mine, not a mining tenement granted under the Mining Act and the provisions of the Mining Act do not apply to a PM except the specific extent nominated in the Mining Act
APPROVALS
On 23 December, Hanson submitted a Mine Operations Plan (MOP) Review Report for White Rock Quarry to the Department for Energy and Mining (DEM). To ensure openness, Hanson has provided a full copy of the document as submitted, in the link below. Note, this link is to the document as submitted by Hanson and it will now undertake a process of assessment by the DEM with a view to achieving a final document for approval. The final document will also be posted on the website once approved by DEM.
Below is information regarding the approvals that are held, administered, and regulated under the Mining Act 1971. As per the requirements under Section 73Q of the Mining Act 1971, a MOP document is not a publicly viewable document, however, a copy of the relevant Objectives and Criteria can be requested via the DEM.
DEM have recently uploaded an information page onto their internal website that provides additional information on the site and has included a section incorporating Frequently Asked Questions.
https://energymining.sa.gov.au/minerals/mining/mines_and_quarries/white_rock_quarry
CURRENT
The White Rock Quarry currently is regulated under a MOP. This document was authorised by what is now known as the DEM. This current document, including the related quarry development and rehabilitation plans and the Objectives and Criteria, are dated and therefore Hanson have undertaken a detailed MOP Review.
MOVING FORWARD
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The Hanson business has recently undertaken exploratory drilling that has informed future development. The source rock has been analysed and tested and presents extremely high quality for uses within the construction industry
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A MOP Review has been developed, including a new development plan. This plan takes into account many environmental aspects including:
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Air Quality
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Visual Amenity
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Noise
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Blasting
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Surface Water
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Groundwater
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Flora and Fauna
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All of the above mentioned items are included and presented within an Environmental Impact Assessment
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In brief, the MOP Review process includes:
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Submission of the MOP Review document to DEM (submitted 23 December 2020). Hanson appreciates the feedback provided to date and have incorporated concerns into the Impact Assessment section of the MOP Review.
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DEM will undertake a rigorous assessment process, which is likely to entail the provision of the document to specialists in each field of environmental management including Environment Protection Authority (EPA), Department for Environment and Water (DEW), Native Vegetation Council (NVC) etc to comment on the relevant aspects within the document.
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If further information is required to demonstrate capability and adherence with legislative requirements it will be requested of Hanson.
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If and when approved, the public can request an update of the Objectives and Criteria that support the MOP Review document.
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RESOURCES AND PRODUCTS
As existing extractive industry resources supplying the Adelaide metropolitan market continue to be depleted and new resource opportunities become increasingly rare and more difficult to develop as a result of urban development, the White Rock Quarry presents the opportunity to provide long term, quality compliant and cost effective building materials for major projects and general construction to the metropolitan area.
The resource is known to the Adelaide Construction Market as hard and durable. The resource supports a multitude of markets including:
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General Fill
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Concrete Aggregate
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Roadbase
In mid-2019, 9 new diamond drillholes (core samples) were undertaken.
A largely gradational weathering profile was observed, with the greatest extent of weathering observed toward the surface. The upper siltstones were highly to moderately weathered with the meters of interbedded siltstone and sandstone showing slight to moderate weathering throughout the core. These layers were also noted to have medium to hard strength.
The quartzite, whenever observed was fresh and hard. Below the quartzite the siltstone and sandstone units varied in weathering from moderately weathered to fresh. This is a reflection of the faulting and jointing throughout the deposit creating weathering channels causing the rock to be weathered at depth.
OPERATIONS
The White Rock Quarry is currently authorised to operate 24 hours x 7 days per week, however normally the site only works throughout the daytime periods within the quarry. At times of high market demand, the concrete plant located onsite will operate 24 hours, 7 days per week.
To refine these operations, the MOP Review (submitted 23 December 2020) proposes to keep the abovementioned broad operating hours, however, allow for ‘normal’ operating hours to be included:
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Extractive Industry operations 5.30 am – 6.00 pm and 6.30 am to 12.00 pm on Saturdays or as required.
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Blasting between 9.00 am and 4.00 pm Monday to Friday, and Saturdays if required.
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Concrete Plant & Transport operates 24/7
The quarry works as a general open cut quarry operation and includes the following aspects:
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Overburden Removal – Overburden is the material that is located on top of the main resource, it is utilised to open up areas for extraction and then utilised in progressive rehabilitation of the site
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Drilling and Blasting – The Insitu rock is fragmented using explosives. Drillholes are drilled using a percussion drilling rig, once all of the shot is drilled it is then loaded with explosives. All blasts are monitored for Vibration and Air Overpressure and require compliance with AS2187.2
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Load and Haul – Material from the blasted face is loaded onto dump trucks via Excavator and/or Front End Loader and transported to the Crushing and Screening area for processing
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Sales – quarry material sales are stockpiled near the crushing and screening plant and then distributed via the weighbridge to market. Concrete sales are dispatched from the Concrete Batching Plant, agitator trucks at times traffic site in the night time hours as required
THE ENVIRONMENT
The surrounding environment is of importance to Hanson. Recent initiatives and update modelling within the MOP Review include:
WATER
Hanson have invested heavily into the effective management of surface water at the site. Recent investment includes the delivery and construction of Sediment Basin 1 (SB1). SB1 is designed to capture significant volumes of surface water, which is then allowed to settle prior to being discharged back into the surrounding environment.
DUST
Quarrying as it is known, includes the disturbance of ground, crushing of rock, rehabilitation and trafficking on unsealed road networks which can result in dust emissions, particularly in dry, hot weather. Hanson is committed to reducing dust impacts and have undertaken detailed Air Quality Modelling to inform the MOP Review process. A new plant is proposed and will include further mitigation measures to what is currently used at the site, including full encapsulation of the crusher, screens, conveying systems.
RESPIRABLE CRYSTALLINE SILICA
Hanson have appreciated the engagement with stakeholders throughout the development of the MOP Review. One (1) aspect that has had concern from residents is that around Respirable Crystalline Silica or commonly known as RCS. To expand on the already modelled air quality data undertaken for the MOP Review, subconsultants Air Noise Environment Pty Ltd (ANE) have been engaged to undertake further assessment on the predicted RCS emissions associated with the Quarry Development Plans presented within the MOP Review. Importantly, ANE have modelled the initial Stages 4 & 5 that are no longer a part of the MOP Review Quarry Development Plans (changed for Stage 3a (reduced disturbance area)). The summary findings from the assessment predict that RCS concentrations for each stage of the quarry (1-5) are well below the criteria of 3 micrograms. A copy of the RCS Assessment can be viewed below:
NOISE
The site has also undertaking Noise Modelling to inform quarry development into the future. The implementation of an encapsulated plant will assist in reducing current noise sources. Additionally, the quarry plant will be relocated to the pit area, increasing the separation distances to the residents of Skye area and utilising the surrounding topography to reduce noise at residential locations.
BLASTING
All blasts are monitored for Vibration and Air Overpressure and require compliance with AS2187.2.
The site maintains a register of adjacent neighbours that want to be informed on the day of blasting occurring. If you would like to be informed via this mechanism please contact us via the below Community Feedback form.
NATIVE VEGETATION
The site abuts Horsnell Gully Conservation Park and Giles Conservation Park. Hanson has been liaising with DEW and interest groups to ensure species lists are well understood and used in rehabilitation
GROUNDWATER
Groundwater studies including pump testing has been undertaken using the diamond drilling exploratory holes to inform the quarry development. An interpreted groundwater level has been provided and the pit design ensures a three (3) metre buffer is maintained to protect groundwater sources within the area.
REHABILITATION
Proposed staged rehabilitation is presented within the MOP Review document. Visual modelling has informed the rehabilitation strategy and importance is given to reaching a terminal boundary as early as possible, to enable the staged rehabilitation of the site. Soil and overburden analysis has informed the batter angles to be used for the best chance of rehabilitation success rates post vegetation planting.
THE COMMUNITY
The community is a very important stakeholder to Hanson. The quarry has been operated since the mid 1940’s and is planned to operate for more than another century. It is important that Hanson understands the community views in relation to the future development of the site. All adjacent landowners were sent a letter of invite to the recent information sessions. The sessions were well attended and some great feedback was provided to Hanson for consideration when developing the MOP Review document. Some of our friends close to the quarry assist with relocation of fauna, inform us of concerns whereby third parties are involved using our land and all of this information is greatly appreciated.
FEEDBACK CONSIDERED
Community feedback has been carefully considered in the final MOP Review document that is to be submitted to the DEM. Hanson appreciates all of the feedback that has been provided to the business regarding the MOP Review and acknowledges the time and effort that was put into participation and provision of feedback. Hanson want to ensure that the community is aware that concerns are acknowledged and that a number of additional mitigation strategies are being developed to ensure that items raised are addressed appropriately.
We have been working hard on the update to our Quarry Development and Rehabilitation strategy from what was initially present during community consultation. The main item that has been amended is limiting the available ‘disturbance area’ per stage of the quarry life. You may ask why? We have been fortunate enough to visit some stakeholders houses, and to those people we are grateful. It has provided us with increased context on the concerns that matter to you and your family. Upon review of our initial round of Quarry Development and Rehabilitation Plans we felt it necessary to commit to further rehabilitation planting earlier in the quarry development, to reduce the overall ‘disturbance area’ per stage. In addition, we have substantially reduced the overall quarry footprint that is submitted as part of the 2020 MOP Review. This can be seen in the staged development drawings shown under the "Operations" section of this website.
For reference, the current ‘disturbance area’ for the site has been calculated at 41.6 Hectares (ha). With the increased commitment to fast-tracking the rehabilitation strategy, the ongoing disturbance areas have been calculated at the cessation of each stage as:
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Current disturbance area - 41.6ha
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Stage 1 - 44.6ha
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Stage 2 - 34.8ha
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Stage 3 - 27.6ha
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Stage 3a - 12.1ha
The reduction of the overall pit shell from the proposed five (5) stages has significantly reduced the available reserves onsite and therefore value of the Site from an economic perspective, however, Hanson acknowledge that stakeholder engagement is a key consideration to the viability and performance of this Site for the long term and want to ensure that the Site can coexist with the surrounding stakeholders.
COMMUNITY FEEDBACK
YOUR FEEDBACK IS IMPORTANT TO US
Hanson does and will continue to strive to operate White Rock Quarry with ethics, integrity and to ensure ongoing stakeholder relations and coexistence is maintained. Your feedback is taken onboard with our operations and we value your feedback.
The feedback period via the Hanson White Rock Quarry Website has now ceased for the purposes of informing the MOP Review report.
Thank you to all of the community members who have provided their feedback to date via the feedback form to date. Hanson are now working hard to ensure that each submission is responded to and that your feedback is considered in the MOP Review process. We will continue to provide updates on how your feedback has been considered, via this website in addition to via individual responses.