Family business Hall Earthmoving is at the start of a major upgrade project which sees the company partnering with FINN Environmental, Hydro Tasmania and its consulting business Entura to ensure stringent environmental controls are met as it upgrades a working dam in Tasmania’s protected wilderness
For Chris Hall and his family business Hall Earthmoving, work has just begun on one of the company’s largest projects in its 40-year existence – Edgar Dam.
Hydro Tasmania has contracted Hall Earthmoving to undertake upgrade works on Edgar Dam, a 17m-high earth embankment dam that sits at the south-eastern end of Lake Pedder. With the lake sitting within Tasmania’s Wilderness World Heritage Area, the upgrade work is seeing Hall Earthmoving not only engage in the challenges of upgrading a working dam but also working within strict environmental controls to protect local flora and fauna.
Specialised focus
For Chris Hall, speaking with Earthmovers & Excavators as preparation works got underway at the remote site, dam building is in his blood. With Hall Earthmoving founded by his father Mick in 1984, his previous work on Tasmania’s hydro projects saw the Hall family become specialists in dam building.
“My dad has a passion for earthmoving and dam construction, from right back when he started in construction at 17/18 years old,” Chris says.
“He worked tirelessly through the ‘80s to pay the business off and grow it, so by the mid-90s, he had about 30 personnel and he was doing civil works, forestry and road building, alongside dam earthworks.
“Then, in the early 2000s my father became ill, so he scaled it down, selling off the forestry side of the business and focusing on his agricultural clients and other dam works.
“Back in 2009, when I finished my apprenticeship, I joined the business and we’ve been progressively growing it back up to just shy of 20 employees.”
Chris says the focus is now on positioning Hall Earthmoving as a local business that has the expertise, gear and personnel that can take on large-scale civil projects, hence its success in winning the Edgar Dam Upgrade contract.
“We wanted to focus on large civil construction projects and deliver them internally as we didn’t like being a subcontractor or third party hire company,” he says.
“We built up a good management team and now we can comfortably deliver $30 million to $40 million civil projects. We did all of the bulk earthworks for the Bridgewater Bridge’s southern traffic interchange in Granton for example.
“We also do a lot in aquaculture, building hard stands, irrigation channels and dams, as well as some work in mining.
“We’re very lucky that Mick is still heavily involved in the business, as well as my mother. We all share a passion, and my mum’s very much involved in the administration side of the business, which gives me the freedom to base myself on a project with my clients to give them that quality service.”
Edgar Dam
In December last year, Hydro Tasmania announced that it had awarded the contract to upgrade Edgar Dam to Hall Earthmoving. As Australia’s largest renewable energy generator, Hydro Tasmania operates seven hydropower schemes across the state, including the Gordon-Pedder Scheme – the largest water storage in the country.
Built in 1972, Edgar Dam is now being upgraded as part of Hydro Tasmania’s rolling program of strategic maintenance work to ensure the safety and operational efficiency of its assets.
With Hall Earthmoving having undertaken various smaller-scale works for Hydro Tasmania over the past 10 years, Chris says this experience meant that his business was well-placed to take this project on.
“We’ve just kicked off the project, doing some preliminary site works, which includes setting up environmental controls, clearing regrowth vegetation from the site and establishing an office and amenities units, ready to get stuck into work along the dam wall,” he says.
“The unique thing about that project is that it’s located within a World Heritage Area, which comes with its challenges as to what we can and can’t do at that site, but my staff are very aware of the additional responsibility this brings and it’s a great project to be working on.”
With Hall Earthmoving having previously built tailings dams for a mine in the World Heritage Area, Chris says this provided the experience required to handle the environmental considerations in place at the Edgar Dam site.
“We will be living out on the project – we’ve got a 28-person remote camp that we’ll be building within the existing Edgar Dam campground, to minimise the number of vehicle movements in and out of the site,” he says.
We’ll be removing a third of the concrete capping on the southern face, removing materials to bedrock, then layering sand, gravel and rock. Together these materials strengthen the dam by filtering any future seepage and weighting the existing structure in the extremely unlikely event of an earthquake. This should take around 18 months, with the project expected to be completed by mid-late 2026.
“This will be done in approximately 50m sections to ensure that the dam is safe. And there’s also a lot of monitoring and dewatering, and other things that we need to remain compliant with during the work.
“We’ve got a really tight construction envelope, because it’s in the World Heritage Area. Therefore, what we need to do is manage the excavation of unsuitable material and have a very high quality sediment erosion control plan that encompasses three sediment ponds and a filtration tank with a discharge manifold.”
With the only access to the site being an unsealed road, Chris says this adds further complications.
“There is a large logistical challenge regarding the material we use as we are restricted by tight specifications, so all material needs to be imported into the project,” he says.
“This means the access road and the remote nature of the project needs a lot of attention to detail. We have to maintain the road and ensure any runoff is compliant. There are a lot of significant streams along the way so, with the amount of vehicle movements that will happen along there, we’re going to make sure that we maintain tight water quality and biosecurity controls. We’re putting in several heavy vehicle wash bays for the project, and they’re there to ensure that any vehicles moving around site don’t transmit weeds up and down the construction corridor road.”
Caterpillar the brand choice
With Mick being a lifelong fan of Caterpillar machinery, Hall Earthmoving currently has an extensive fleet containing 637K scrapers, 374NG, 349NG and 330NG excavators, D8N and D9T dozers, 740 and 745 articulated dump trucks and a 14M grader.
Chris says his father had a dream back when he started his business, which was to own a Caterpillar dozer. Eventually, the dream came true when he purchased a D7H, which is still running in the fleet.
“With Caterpillar we just see great performance with the product and it’s high-quality plant,” Chris says.
“The newer stuff is doing great with fuel burn. Our two recent additions to the fleet, two 637K scrapers, have dropped 250 to 300 litres a shift in fuel burn compared to their older models.
“Caterpillar is also at the forefront of technology. We’re a small business, but we have a high percentage of trainees as we pride ourselves on not taking operators out of the market. Out of 15 to 20 plant operators, four to five of them are being trained. So, when we’ve got a premium product with technology aids, it helps us upskill our employees quickly.”
Upgrades underway
With regrowth vegetation now being cleared on the Edgar Dam site and material stockpiles being built, Chris says the team is excited to get the upgrade works started.
“It’s great to work with Hydro Tasmania,” he says.
“We love delivering our projects for our clients and seeing it progress all the way from the tender phase through to the very end where we’re putting the door on the pump shed. We’ve got a common goal to deliver the best quality product we can, while keeping Tasmanian communities, plants and animals safe.”
For updates on the Edgar Dam project, visit: connect.hydro.com.au/edgar-dam-strengthening-project
- Subscribe to our free weekly newsletter to receive the latest news in the earthmoving industry
- Never miss a great deal and subscribe to our monthly magazine
- Download a free copy of our latest digital magazine to catch up on the biggest news and developments in the earthmoving industry