Quarrying & Mining Magazine
Quarrying

Blasting for boulders

Alan Titchall visits a unique quarry in the Nelson region that produces products from hard limestone and greywacke.

It’s an old industry adage and a true one – you never find good rock on the sunny side of the hill. But on my visit to the Lee Valley Limestone quarry this winter, a low-lying sun lit up the face like a movie set, as a soft mist lifted from the valley floor – providing a picturesque, if frosty, worksite.
This quarry is located up River Terrace Road not far from Brightwater and the headquarters of its owner – Taylors Contracting. Cut into a steep side of the valley, the operation is on two levels.
The site was opened just before WW2 to produce lime and for the latter years for cement that was made further up the valley. Taylors Contracting bought it 12 years ago to extract boulders from the limestone and aggregate from a separate layer of greywacke butting up against the lime.
The boulders are used for coastal and river erosion contract works in the Tasman and Golden Bay regions and, typical of the limestone in the area, it is reasonably hard, with a D setting of 2.6 plus. The greywacke is crushed down to make M40 and NZTA spec material, mostly for the company’s own needs.
“Apart from boulders for coastal and river protection work, we cater for our in-house aggregate needs, such as small subdivision and forestry work,” says quarry manager Neil McKay.
The company also shifts gravel and plants a lot of trees to mitigate erosion in the region.
“Some 20,000 native trees and plants are getting planted each year as part of our contract with Tasman District Council (TDC),” says Neil, who has worked for Taylors Contracting for the past 12 years and has worked in the local extraction industry all his life. He carries an A-grade quarry manager’s certificate and manages his own blasting. Out of the five workers in this quarry, three of them have A-grade certificates.
“We do our own specialist blasting, have our own drill rig, and have developed our own technique of blasting faces to get the big rock.
“At the top end these boulders weigh between five to six tonne, and some sites have sub-specific needs for rock upwards of 10 tonne. Generally, we chase around five tonne.
“We drill and blast, then use a 30 tonne digger to pull them out and load onto semi-trucks – all six wheelers. The deckings takes a hell of a pounding, especially when the boulders slip out of the bucket.
“We’ve built two special decks on our semis out of a new steel product from Real Steel, which is working very well. One deck is seven or eight years old, and it’s still in good condition.”
The operation is very much a winter one as the company tries to do all its summer work in Golden Bay. Boulder and crushing work is largely done on two separate levels – with both floors and the haul road a quagmire of sticky clay from the overburden, which is about 1.5 metres thick.
“This quarry is at its busiest time in winter. We probably crush nine months of the year,” says Neil.
In summer half the crew disappears to do other work for our rivers contract. It gives us time to clean up, but we always continue some crushing.”
The level closest to the road is the main bench with a mobile crushing plant and storage area.
The Terex (TransDiesel) was only four months old at the time of my visit, was crushing forestry grade material, being fed with a new 23 tonne Hitachi excavator dedicated to the job.
“We’ve got a larger crushing unit that is down in Kaikoura working on crushing slip material, so we bought this smaller one just to keep production up,” says Neil.
“Because of the wet, muddy conditions here we were after a crusher that could do the job, sorting the waste material out. We did look at quite a few, but TransDiesel, who we have had a long relationship with, came up with this model and we’re happy with it.”
The quarry doesn’t use a weighbridge and outcoming material is weighed by Loadrite. A local weighbridge just down the valley is used for weighing the big rock.
Being such an old quarry, the consent is based on an existing “grandfathering right”.
“Which makes it easy to operate but we do behave ourselves. We’ve just got a couple of neighbours, who we work in well with.”
Neil says he has been working in quarries in the region since he was 20 years old.
“So I haven’t moved too far from home, but I enjoy it. I also enjoy working with a small workforce and we have good team of guys.
“I take a couple of them every year to the AQA/IOQ conference to see new things. It’s also a way of supporting them for what they’ve done for us over the year.”
Taylors Contracting began in 1971 with the late Bob Taylor and his wife Marlene. The family business is now run by Bob and Marlene’s three sons, Charlie Taylor (Contrafed Publishing’s chairman) and his brothers Matt and Arthur.
“What I like about them is that when you take an idea or problem to them; they always listen to what you say and they are good people.
“Charlie as CEO has a good business vision, while Matt is good with machinery. They complement each other and know how to get things done.”

This article first appeared in Q&M‘s issue.

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