Located in Woodhill Forest northwest of Auckland with its entrance on State Highway 16, a new black sand quarry is in operation.
It is not often that Q&M magazine gets to see a quarry start-up, particularly one close to Auckland city, and one that has raised standards above regulatory requirements.
Alan Titchall explains.
A new black sand quarry started operating near Auckland City in February of this year as a well-planned project collaboration between the Woodhill Group and the local iwi landowner – Ngati Whatua o Kaipara.
It is located in Woodhill Forest northwest of Auckland with its entrance on State Highway 16, sharing the main forestry haul road (Restall Road).
Woodhill Group director Michael McCall says the project took over four years to consent and set up.
Through Andy Loader of First Rock Consultancy, I meet up with Michael, his wife Carissa (who manages the quarry office), and Malcolm Paterson, the chief executive of Nga Maunga Whakahii o Kaipara Ngahere, which is the commercial arm of the post-settlement entity that manages Ngati Whatua’s interests in its forest lands.
The relationship between the McCalls and the iwi started in 2013, when Michael was given permission to retrieve wood waste from the forest operation for a firewood business.
Ngati Whatua o Kaipara settled a Treaty of Waitangi claim with the Crown in 2013. This required the
setting up of a new post-settlement entity (Nga Maunga Whakahii o Kaipara) to receive and manage the settlement assets.
“Nga Maunga Whakahii o Kaipara is tasked with managing and growing the commercial assets and investments of our hapu, and the profits fund our tribal development,” Malcolm explains.
The Woodhill Forest was the largest piece of Crown land in the area that could be considered through the Ngati Whatua o Kaipara Settlement.
“It has always been for us, and in its own right, a very important cultural landscape. It contains a lot of our tribe’s historic sites.
“The lands were originally lost through sales and public works when our ancestors were supportive of it being turned into a Crown forest to stabilise the sand and support development in the region.
“I have letters written by my grandmother in the 1950s petitioning over our promised access into and across the forest not being upheld. I also have letters from my mother in the 1980s raising the same concerns.
“A lot of promises were made back then in regards to jobs for our community, but when the forests were privatised in the 1980s those jobs were lost. And our access to these lands was not always upheld.
“We never lost our mana whenua over, or cultural, interest in these lands, but our legal authority had been extinguished.
“So it’s great to have the land back in tribal ownership, but that also comes with responsibility too.”
The majority of the pine trees on the land are for now still owned by a company with rights of use, but as they harvest, the newly planted crop is owned by Nga Maunga Whakahii o Kaipara and its joint venture partner Matariki Forests.
The iwi commercial development arm has tasked itself with finding other ventures that fit in with the landscape and its cultural/social objectives. This includes horse trekking (an extensive track network is maintained on the lands), mountain biking, hunting programmes, beehives and now carefully managed sand extraction in a specifically chosen location.
Some of these activities already support the training and employment of tribal members and it is anticipated that this will be the case with the sand extraction and clean-fill operations over time.
A quarry/clean fill project in the making
Malcolm says Nga Maunga Whakahii o Kaipara went out to market to find an operator for a proposed sand extraction business and ended up working with the Woodhill Group under a new mining permit.
“Through the firewood venture we already had a trusting relationship with Michael and Carissa,” he says.
As a contractor, Michael McCall recalls receiving a phone call from a customer five years ago who needed 800 tonnes of sand for a local volleyball court, around the time the previous Woodhill sand quarry closed down.
“We had just shifted from South Auckland to this area and I did a bit of digging and one thing led to another with the idea of extracting sand from this area and filling the void with clean fill.
“Around the Auckland area there is a big call to get rid of clay, rocks and surplus topsoil from subdivision sites, particularly in the winter, when other clean fill sites struggle.
“The nature of this sand site makes it unique and stable for clean fill, which can be trucked in, and then black sand taken out on the same trucks.”
The black sand is in demand as a fill product for supporting project piping and cabling infrastructure, he adds.
Malcolm drove the operation to “get the wheels in motion”, says Michael, with most work achieved during 2018.
The result is a 40-year Crown mining permit and a very uncommon 35-year Council consent for the extraction and clean fill that is bundled, but kept separate, so if the sand resource runs out, the clean fill can keep on going.
As a collaboration project between contractor and landowner both parties acknowledge the “pragmatism” and overall big picture support shown by the Auckland City Council in helping to get the project off the ground.
As Malcolm says, such projects can fall down a rabbit hole over environmental consents. In this case ‘dust’ was an unknown issue that was offset largely through pest control in the adjoining native bush that is home to rare native gecko.
“We also agreed to dust-suppression measures and barrier planting for containment,” he says.
“The extraction work won’t attract any more predators, but pest control should more than off-set any impacts on lizards and geckos from dust.”
Malcolm adds that the project has its own set of environmental standards that go beyond regulatory requirements.
“As a land owner, we worked very hard through the consent process to go beyond council requirements.
“And we believe we have a gold-standard extraction operation with in house protocols over the extraction and clean fill that go beyond the council’s own specifications.
“We like to think we are developing what may be a ‘model’ for the rest of the industry, especially with combined clean fill. From the sources of the fill, to the continual testing and deposition regime at the site, we reduce the risk of any contamination but also have the ability to deal with any incident should it happen.”
The black sands of the area don’t contain as much iron as is found in the same volcanic sands south of the Manukau Harbour, which are extracted and processed at the Glenbrook steel mill.
These volcanic sands are part of an extensive beach-land area sweeping along the west coast from Taranaki to the Kaipara Harbour and have been also blown inland over centuries.
By the time the development of Auckland city caught up with the Woodhill area at the end of the 19th century, the encroaching mobile sand was threatening farmlands and the new northern rail line. European marram grass was first planted to try and stabilise the sand (now a pest plant across our coasts), and then, in the early 1950s, pine forests.
The trees have worked well, and harvesting is now up to its third harvest rotation. The pine doesn’t grow very fast in the sand, but grows very strong.
The quarry site is a large stabilised and isolated dune (30 metres deep) about three kilometres from the beach that will not be naturally replenished, which makes it a good, well-filtered, clean fill site and with easy access through SH16 to the Auckland region.
Malcolm says although they have no cause to suspect this particular 30 hectare site (sitting in over 12,000 hectares of forest) specifically contains cultural material relating to ancestral use of the land, they are cautious, and work will stop the moment something like a midden is found.
“As part of our kaitiakitanga [guardianship and conservation] our protocol is simple. If you see something stop and contact us.”
I visited the quarry some months ago when it had only been going a few weeks, and a single loader with a six tonne bucket filled a steady stream of contractors’ trucks (most of a 37 tonne capacity) with black sand.
Michael was very happy with the loader’s performance.
“We have loaded 2500 tonne on one tank, but we are aiming for three. And you don’t get that performance in a regular quarry.”
There was a Loadrite system on the loader with plans for a weighbridge to be installed once the clean fill operation gets going, plus a new elevated site office to look down and inspect the fill as it is brought into the site; and a one-way road system.
Before the trucks are loaded with sand an attachment that fits on the end of a digger will wipe the trays out, which eliminates the need for water, says Michael.
As a consultant Andy Loader pops in once a week for a site visit, and he set up the health and safety protocols.
“It’s great to have someone with Andy’s experience. It might be a simple operation but there’s always a few things he says we can do a bit better, which is always helpful.”
Since my visit the operation has pushed on with its plans.
“We now have purchased a 1021 Case wheel loader and a 210 Case excavator to prepare and work in the cleanfill that will open this month [August 2019]”, says Michael.
“In the wheel loader we have a Loadsense scaling system and will eventually couple with the weigh bridge and automated kiosk system that will enable semi-autonomous scaling systems in our operation.
“This includes the cleanfill. All this information is then sent to the Cloud which we can access via Apps on our phones or log-in where we can export/import for automatic invoicing.
“What this means is less paper and more accuracy in recording information and instant customer invoicing.
“So, four months into the start of the operation back in February we can say we are really getting geared up to serve local project needs for quality sand.”
And, with little overburden, a well-drained site, well-thought-out designs and plans to cut down loading times and expand the face, this project is heading to set an industry standard in quarry/cleanfill.
And, as Mike says, “It’s a great collaboration between two parties, operator and landowner, and we are all on the same page.”