Aggregate is a vital material that is essential in the development of buildings, roads and infrastructure.  New Zealand uses 9-10 tonnes of aggregate every year for each adult and child. (Aggregate & Quarrying Association - https://aqa.org.nz/fact-files/).

In Canterbury, this demand may be slightly higher due to population growth, Christchurch is still rebuilding after the earthquakes of 2010 and 2011, and the proposed stadium is under construction. Selwyn is also the fastest growing district in New Zealand with Rolleston being the main area of growth for both residential and commercial development.

Existing quarries in Canterbury are vertically constrained to an approximate depth of 10 metres due to underlying aquifer systems, so tend to expand horizontally. In turn, the expansion of existing quarries is often constrained by surrounding activities and land uses, and issues of reverse sensitivity.

Winstone is implementing alternative aggregate sources such as recycled concrete to meet New Zealand’s aggregate demand. Currently there are barriers in place to wide-scale use of alternative aggregate sources. The barriers are complex and encompass existing policy frameworks, customer perception, technical constraints and economic factors. As a consequence, these alternative products will likely only form a small percentage of the market for the foreseeable future.

Given the constraints to expansion of existing quarries and current barriers to the use of alternative aggregate sources, Winstone seeks to develop a new quarry to meet projected demand and provide a long term, secure supply of aggregate to the Canterbury region.

The projected demand is detailed in the New Zealand Institute of Economic Research report included in the application. The report describes the importance of quarrying, and the projected demand for aggregate resource in the Canterbury region. 

Without continuing secure access to aggregate sources close to demand, infrastructure costs would rise, and its affordability would decrease. This would have impacts for all the region’s industries that rely on that infrastructure, both directly (infrastructure providers) and indirectly (infrastructure users, such as transport operators).

The proposed quarrying activities will be undertaken in a series of phases as set out in the Quarry Staging plan in Appendix 5 of the Application.

These phases and the indicative timings are the Construction Phase being 0 to 5 years when works such as constructing the vehicle crossing and access, the buildings, the permanent bund along Aylesbury Road and the stockpile are undertaken, Extraction Phase being 6 to (approximately) 60 years and Completion and Final Rehabilitation at year 60.

The timing is only approximate, having been developed based on current demand projections for the quarry.

The quarry will have a life expectancy of at least 60 years based on current demand.

The application for resource consent seeks to provide as much certainty about the Proposal over the anticipated life expectancy of the quarry, as is practicable and feasible at this time.

Land use consent is sought without the restriction of any term to allow for the extraction of aggregate to respond to market needs over time.

Winstone undertook a detailed process of site selection. In summary the factors which influenced the site selection process were:

• An area sufficient to contain all quarrying activities, internalise adverse effects to the extent practicable and provide a secure aggregate resource over a long period of time in order to minimise the need to develop additional sites in the future.
• Proximity to markets for the resource and State Highway 1. Aggregate is expensive to transport. This dictates the distance that the site can be located from identified markets and key transport networks. Locating near markets also ensures that any reduction in carbon emissions achieved by the quarry operations is not offset by high (carbon) emissions from trucks travelling long distances.
• Distance from large-scale residential populations such as Rolleston, Templeton or Christchurch City. The Site is in a rural area, recognising rural residential properties either adjoin or are near the Site as is Burnham Military Camp to the south.

Development of the Site will commence with the construction of the vehicle crossing for both light and heavy vehicles from Aylesbury Road midway down the Site boundary. The vehicle crossing will be formed to the NZTA / Waka Kotahi commercial vehicle access standard including widening the eastern side of the road and entry side of the access. This exceeds the design standard for vehicle crossings for commercial and heavy vehicles for all roads in the Selwyn District Plan.  The Aylesbury Road accessway will curve into the Site with bunding to prevent direct line-of-sight to quarry activities from the road frontage.

Please refer to an overview of the proposed entrance design at Figure 9 of Appendix 8a of the Application.

The existing vehicle crossing off Grange Road will remain as access for farm vehicles only, keeping the farming and quarrying activities separate.

The site office, staff amenities, parking and weighbridge areas will be established in proximity to Aylesbury Road. The buildings will be no more than 5m in height and will be set back at least 30m from Aylesbury Road.

The weighbridge installation and sealing of 150m of access road between site boundary and the weighbridge will be completed as part of the construction phases to establish the quarry and prior to any extraction activities.

A wheel wash will be established at the base of the exit ramp. All road going vehicles leaving the Site will be required to pass through the wheel wash, which will be over 150m from the exit onto Aylesbury Road.

The Site will be fully fenced with an appropriate farm fence and gated, and the gates will be locked when the quarry is not operating. Areas of the Site which are actively farmed, or otherwise used for an alternative use will also be fully fenced and have an independent access way, providing clear delineation between quarrying and other activities. 

Overburden is the topsoil and subsoil layers that lie above the aggregate that must be stripped and removed prior to aggregate extraction. Site preparation works will require the stripping of overburden within the part of the Site where the stockyard, plant processing areas and the site administration facility are proposed to be located.

The overburden will be used to create a permanent 3m-high landscaped bund along Aylesbury Road, which will remain in place for the life of the Quarry. This bund will run from the site access for 1km south along Aylesbury Road.

The site boundaries along Aylesbury Road, Grange Road, and the boundaries of properties adjacent to Kivers Road are generally fully screened by an established evergreen shelterbelt.  Where there are gaps in this existing shelter belt, these will be planted with the same species of tree. This shelter belt will be retained for the operational life of the quarry except where it is required to construct the new vehicle access crossing to the Site off Aylesbury Road.

The removal of overburden will generally only occur during the earthwork season (typically October to April).  Overburden will be stripped by machinery, loaded directly into trucks and transported to the Site boundary and formed into temporary stockpiles around the Site boundaries (aside from the permanent bund screening the operational area). 

Extraction of the aggregate resource will start with the use of standard quarrying machinery such as excavators, wheel loaders, dump trucks, and wheel excavators. It is not proposed to undertake any blasting.

As the expected life of the quarry is approximately 60 years, it is likely the equipment used for extraction will change as technology advances in terms of energy efficiencies and reductions in carbon dioxide emissions. As new technologies develop, Winstone will seek to utilise more sustainable equipment and plant in accordance with the overall sustainability objectives of Fletcher Building.

Once the aggregate resource has been extracted, material will be transported to the processing plant by truck along the haul road. In the future, material may be transported to the processing plant by way of overland conveyors. Overland conveyors provide an efficient, cost-effective way of moving material using renewable energy sources.

The first area of extraction will create the plant processing and stockyard areas towards the centre of the Site, approximately 500m from Aylesbury Road. Extraction will use a top-down method using excavators, wheel loaders, and trucks. The material will either be processed immediately with mobile crushing equipment into saleable material or stockpiled in a future extraction area (once overburden has been removed) for later processing.

Once the plant processing and stockyard areas have been extracted to full depth, the extraction methodology will change to extraction from the pit floor, which is expected to be approximately 10m below the original ground level. The extraction area will advance by removing material from the toe of the active quarry face. It is estimated that it will take approximately 5-6 years to extract and process the plant processing and stockyard areas.

It is proposed to undertake extraction with minimal disturbance to existing farm infrastructure (water lines, irrigators, power and buildings), and retain a separation distance of at least 500m from adjoining residential properties for as long as possible.

Extraction will progress in phases focusing within one specific centre pivot irrigated area at a time starting with Southeast, then Southwest and finally the Northern centre-pivot area. Each centre pivot irrigation area will be divided into wedges for extraction to minimise disruption to the existing irrigated farmland. After approximately 10 years, the extraction and rehabilitation will be in equilibrium with 25 hectares of active quarrying area equivalent to approximately a 5-year cycle from extraction to rehabilitation.

It is proposed that the extraction of aggregate will be undertaken in increments of 25 hectares, commencing in proximity to the Site entrance and facilities area.

It is proposed that the areas of extraction will generally be set back approximately:

• 24.5m from Aylesbury Road, extending to 100m along approximately 0.6km of the southwestern corner of the Site in proximity to the adjoining residential properties, and
• 17.5m from Grange Road, adjoining rural zoned land and residential properties to the west extending to 100m in proximity to the Site entrance and adjoining residential properties on Grange Road

Trucks will enter and leave the Site by way of the vehicle entrance on Aylesbury Road. The majority will head south towards State Highway 1. The proposed maximum number of trucks entering and exiting the Site will be 375 per day (i.e. 750 traffic movements). It is not expected that the quarry will achieve this maximum quantity of movements until the latter phases of its life.

Until the intersection of Aylesbury Road and State Highway 1 has been upgraded to a roundabout, the quarry will not generate more than 125 trucks entering and exiting the Site will be 125 per day (i.e. 250 traffic movements).

Early morning truck movements between 5am and 7am will be limited to 10 truck movements per hour:

• Monday to Saturday (excluding public holidays) on up to 30 days per annum and,
• Sundays excluding public holidays) on up to 15 days per annum

It is unlikely that any trucks will return to the Site during these hours given the distance to markets.

Please refer to the Rehabilitation description here.