Sustainability in Construction 👷 Turning Quarries into Forests

Welcome to the very first episode of UK Construction Podcast hosted by the team from the UK Construction Blog! 

In this episode we talk with Tom Redfern, Senior Sustainability Manager at Aggregate Industries, to uncover the ground-breaking ways the construction industry is going green.

From turning quarries into forests to recycling asphalt infinitely, Tom breaks down how sustainability is changing the game in construction and how Aggregate Industries is contributing to this mission. 

We also dive into carbon capture in concrete, the push for green hydrogen in asphalt production, and what it takes to manage sustainability across 200+ sites. 

Topics Covered:
✔️ How asphalt and concrete can be infinitely recycled 
✔️ The surprising impact of carbon capture in construction 
✔️ How a quarry was turned into a 64-hectare forest 
✔️ The future of green energy in asphalt production
✔️ Why sustainability is becoming a major business advantage

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Thank you to our sponsor for this episode, WebMotion Media:
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Follow Tom Redfern on LinkedIn: https://www.linkedin.com/in/t-redfern/

The Friends of Paxton Pits: https://paxton-pits.org.uk/about-paxton-pits/the-friends-of-paxton-pits/
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Transcript

Sustainability in Construction - Turning Quarries into Forests from the UK Construction Blog Podcast

Interview with Tom Redfern on Sustainability at Aggregate Industries

Q: What's your background? What did you study at university? And what was your career path before Aggregates?

A: It's a little bit of a varied one. I started with a geography degree up in Liverpool. When I left, my passion was always that environment and sustainability.

But sustainability wasn't massively on the radar. It was much more environmental compliance heavy. So I joined a company in Stafford where I worked for about two years. I went to Macom, which I still do today, and I worked there for eight years, covering the whole breadth of sustainability, still environmental compliance, but community and social impact, carbon and decarbonization that progressed there.

I became head of sustainability, ultimately, before looking for a new challenge and something different. I joined Aggregate Industries, which is part of Holcim, three years ago, based out of Leicestershire in Coalville as a senior sustainability specialist. My role again is quite broad. Now a lot more of a communities piece, so still that social impact and social value, also heavily on nature and environment.

So hopefully a lot of the good stuff we can talk about today. How we interact with nature and how we maintain our environmental compliance and core finance of doing business.

Q: For anyone who hasn't heard of aggregates, I know I've been aware of them myself just before I was even involved in the construction industry, but just seeing the big trucks driving around on the motorway and things like that.

A: If you've never seen Aggregate Industries, as soon as you start looking at the trucks, you'll realize that we're a national business covering all the way from Scotland down to Cornwall. We're owned by our parent company, Holcim. Holcim owns businesses much like Aggregate Industries around the world, but essentially we're a family of businesses within one umbrella of Aggregate Industry.

We have a number of core components. We have our aggregates businesses - quarries. And when you think about nature and biodiversity, that's a massive part of what we do. We also have a cement plant located just on the edge of the Peak District. We have a ready mix business and ready mix plants spanning the UK.

We have a concrete products division, so a number of concrete products factories, which develop traditional blocks and paving and slabs. And then we also have our asphalt business, which is also associated with a contracting business, literally going out and laying the road.

For anybody who hasn't heard of Aggregate Industries, I always think the easiest way to think about it is: we go from the moment we take a product or material out of the ground and then take that all the way into a final product which we can then sell out onto the market and in the case of asphalt also do the actual laying.

Q: You actually do the laying of the surfaces and things?

A: Yes, big framework contracts for us, whether it's down to smaller scale supermarkets and things like that.

Q: I didn't realize. I assumed you were just the pure supplier of the raw materials, so to speak.

A: Yes, for the asphalt, we've been nominated for all the rest, we're the supplier of a product into the market, and we wouldn't go out and do the actual works.

Q: Am I right in thinking, are you guys one of the biggest in the UK?

A: Yes, it's us and a few other big names. We're one of the biggest suppliers across the UK.

Q: That must be, just the pure nature of the business, in what it is you guys are doing, quarrying and cements and everything else. That must have significant opportunities for all the sustainability and the climate side of things. Which I understand you've been quite heavily involved in - you're one of the spearheads of the sustainability plan.

A: Exactly. Firstly, I think both the impact and the scale of the business is huge and you're right in terms of what we do. When you think about cement and quarries, it's big scale and it's quite a large impact.

But with that also comes massive opportunity. The first thing we did when I joined the business three years ago was we developed our sustainability strategy, which really focused on where can we have the most impact? Where is our biggest impact? And where can we have the biggest impact?

We've focused around four or five core pillars:

• Climate, so decarbonization and energy management piece that we all know.
• Nature and environment, so a lot about biodiversity, biodiversity management, but also nature - much more than that, which I'm sure we'll talk about.
• As well as that core environmental compliance piece, which is just central. If you don't do the compliance piece right, you need to have that as your foundations to build the rest on.
• There's then a circular economy pillar to the strategy which is massively important to us as Aggregate Industries and also Holcim as our parent company.

We see such massive value in reusing materials back into the products that we make. And this is all interlinked, from a climate decarbonization point of view, but also particularly a nature point of view. The more we can reduce that pressure on land and use of virgin material, the lesser our impact on nature.

We then also have a people and communities pillar. That's all about not just our colleagues, but also our communities and how do we have maximum social impact, acknowledging that our impact can be sometimes not so positive for local communities, but we can also have a hugely positive impact. We need to maximize that going forwards.

And then hope that all four of those feed through to the sustainable products pillar. So that's our innovative products, which are driving the next wave of construction materials.

Q: That's awesome. It's good to hear that big companies like yourselves are actually taking action for this stuff. With regards to the circular economy, I can understand within certain industries, like suppose you're fabricating steel beams or something for inside warehouses. I can understand how they can potentially have buildings being decommissioned, tearing out the steel beams, with some polishing and fixing up, I can easily understand how they could be reused. But what about the asphalt and concrete and things like that? There must be a significantly harder challenge to actually get those materials out and reuse them.

A: It's multi-faceted depending upon the business that we're looking at. But firstly, asphalt and concrete have real strength - they're infinitely recyclable. So we can just keep using these materials again and again.

If we start with our asphalt business in the roads, we're really quite mature in this space, and we've been recycling asphalt surfaces for many years, and we've really known now how to both source the material, and particularly helps when you have a contracting division which is going out doing the roads so we can plane and bring back, but also we actively look on the market to find sources of what we call WRAP, so Recycled Asphalt Planings, to use back in a plan.

For context, we're using about a million tons of recycled asphalt every year throughout the country. We've been doing that for a long time.

But you're completely right. We're looking more and more now at concrete. With concrete, when you make that product, you've got two parts: your primary aggregates that you've used to make it - your sands and your stone that you've quarried, but then you've also got your cement bit and that cement has got all that high carbon intensive process that's gone from making cement in the first place to developing concrete.

So what we really want to do now is to use it back into our products, but also moving it up the value chain. What the construction industry for a long time has done pretty well is demolish a building made of concrete and crush it down and use it as low grade backfill or base material.

What we want to now start doing is move that back up the value chain. We want to start using it back into concrete because it's got that cementitious material in there. That's what's really important to us to keep reusing.

Part of that, you need to find the supply and you need to process it nearby. And that's what we're really on at the moment. London is a great example. It's often referred to as the world's largest urban mine. That's because there's so much construction going on and there's such a high volume of concrete material coming out, if we can capture and harness that, then that's absolutely the way forward.

And we're already trying to go a step above and beyond that. We've recently invested in a technology called New Stark. What New Stark does is it uses carbon from a source where it would otherwise be released. We then take our crushed concrete, or CDM, construction demolition material as we call it - so it's just concrete at this stage still - it's come from your construction site in big lumps, we've crushed and screened it down into something a bit more manageable.

We then put it through this process, developed by a company called New Stark. And what they do is you can then pump carbon back into a chamber because over the life cycle of concrete, it actually naturally absorbs carbon.

What this does is it speeds it up. So what might take a hundred years, we can do in about seven hours. And then after that outcomes, your crushed concrete, which now also has some additional carbon stored, which is certified to gold standard. You can then put back into your process again and create fresh concrete out of it.

Q: Amazing. At a faster rate, basically, than the standard concrete does. That's awesome. Because you always think of - to be honest with you, I didn't even know concrete absorbed carbon. You obviously hear of the other end of the equation more often than not.

A: Exactly.

Q: And with the asphalt and stuff like that, once you've actually got materials back off the roads and things like that, is there much processing that's required? Just wondering about the energy inputs into these processes and things for the actual recycling.

A: Absolutely. So we're constantly balancing this off. Firstly, you want to haul it the shortest distance possible because that road haulage is always - you've got to take the whole life cycle of that process into account. So you need to understand how much carbon is going to haulage, so the shorter you haul it, the better.

And then there's also an element of crushing and screening that product back down into something that can go back in through the plant. So we do this all the time. For everything, we're constantly assessing how much carbon has been associated with that process.

Because we're able to reuse the bitumen, so that binder, which is a real high carbon intensive bit, you still see a benefit coming through from using a recycled asphalt, because you're using less bitumen back into your virgin product.

So it is still a net lower carbon impact.

Q: I can imagine. And have you guys looked into using essentially green energies and stuff for this processing?

A: Yes. We have already quite a significant solar PV scheme rolling out, not just specifically for asphalt, but across Aggregate Industries UK, where we're looking at how we can generate our on-site electricity supplies. Now clearly, depending on the site, you might need quite a bit of solar, so there's always probably going to be a gap.

And we need to look for the wider green energy off the grid, and also we're very much trying to be at the forefront of what comes next, which really for something like asphalt looks like green hydrogen.

Q: Really? Okay, interesting.

A: So we're keen and trying to push in that area to find areas, find sources of green hydrogen, where we can then potentially look to start converting asphalt plants and really that's the next shift and game changer in that energy supply.

Q: I can imagine for the scale of the energy inputs that you guys need, you can't rely solely on renewables. I would expect the peak suppliers and the variability and everything.

A: And if you think about cement production, which is 70 percent of Aggregate Industry's overall CO2 emissions, an absolute key focus for us, even if we were to get all that heat energy that we need to create cement completely carbon neutral or decarbonized, about 50 percent of the carbon emissions resulting from cement production come from the actual chemical reaction that takes place when you're essentially heating rock up to 1400 degrees that releases carbon.

So even if you did the first half and we managed to completely decarbonize the fuels, you would still have this residual carbon emissions, which is why we're part of the Peak Cluster program and looking at carbon capture and storage for our cement plant. And we're optimistic that in the early 2030s we will have a plant in place capturing and storing carbon.

That's the real key and the cement piece to shifting the needle.

Q: And then once that carbon's captured, what happens with it then? Is it feasible to then reuse that within your products and lock it up within the cement?

A: This is where we don't know yet because there's still a lot of work to do with technology. The initial plan is that the Peak Cluster will effectively give way to a pipeline, so a lot of heavy industry, primarily cement plants, which are located around that Peak District area, because the geology was so good for making cement, will then feed into the pipeline, where it will then go up towards northwest, and almost certainly go back into old gas fields that have previously extracted the gas and the CO2 will go back in.

But of course, what we would love to do is to be able to reuse that back into products. That would clearly be a utopia. And as we learn more about technology and the quality for carbon coming out, we can then start to look at what we might do with that going forwards.

Q: Have you guys ever looked into again, it might be a bit further down the line, but any of these micro nuclear reactors? The sign to appear.

A: I'd say not right this second. But we know we need to generate energy. There's technology advances and matures and options become available. We will always review what.

Q: And so I'm writing on staying, you guys have got over 200 sites?

A: Over 200 sites, and that's just in the UK. Scotland and England specifically.

Q: And so how would you deal with implementing this sustainability plan across 200 different sites across the UK. It's going to be a logistical headache to say the least, I imagine.

A: Logistically challenging for sure. And we also have to acknowledge that it's 200 sites, but 200 sites are really quite varying scales. It could be anything from our Glensander Granite Quarry, which is Europe's largest granite quarry, so a really significant quarrying operation, through to a small ready mix plant on industrial estate that might be operated by one or two colleagues.

So we have to first try to make sure it's proportionate and what we're asking has to fit the scale of the impact of what that site has and what resources that site has to deliver it because ultimately we can steer and absolutely support our teams in delivery of strategy, but it is always gonna rely on our operational staff on the ground to really live and breathe it and make it part of what they do to every day.

So what we try to do is set a clear direction and we'll tailor that down to the business specifically. For example, if we look at fresh water and water reduction, which is something that I'm personally really passionate about, the key part of nature strategy, we know that our ready mix business is really heavily dependent upon fresh water. In that business, we have a real focus and drive and a clear steering group set up to help reduce fresh water.

Now, in your asphalt business, which doesn't use water as part of the process, clearly we're probably better at focusing our efforts on decarbonization in that area and increased circularity and using more RAP.

So, we try to balance it to make it meaningful, the business that we're talking to, but we tried to engage colleagues and engage colleagues to all levels of seniority. That's everybody from a site operative up to the senior management team and only by having everybody engaged and buying into the message, you really truly deliver.

Q: I imagine it's, as I say, no easy task to actually straight on the ship, so to speak. There's so many different boots on the ground and things.

A: And you always have to look for your real advocates. There's people within these businesses who are really passionate about what we want to do. And it might just be one small part of the overall sustainability strategy. It might be that they're really passionate about the circular economy, or really passionate about decarbonization, or nature. And those could be your champions and voices out there doing it on the site is really powerful.

We often find far more engaging than somebody from the sustainability team turning up and saying, this is what we'd like to do it.

Q: Absolutely. When you can identify and relate, that's when you have the most meaning and most impact. So it's finding and teasing those people out.

A: Yes.

Q: And once you've found those people, what do you do? So they can, their voices can be heard, so to speak.

A: So we make sure they have a platform to be heard. And that can be for a variety of ways. So we'll set up within most of the businesses, a champions group and on that group will be both people from like myself and sustainability team but also high level senior management from within the division so they feel recognized and they can have those conversations all the way to talk about what they're working on what's important and the ideas.

But it's then also about sharing that broadly across the business and we're quite fortunate at Aggregate Industries to have an internal communications tool. It works a little bit like a social media platform. You can post on there and you can share ideas and anybody from across the business can see it. So if somebody's done something great down in Red Roof and you want somebody up in Glasgow to see it, you got to get it on Blink, give it recognition, share it and promote the messages.

Q: Have you found any examples where this has actually helped with your business growth, on a commercial viewpoint, because obviously this is all great and something every company needs to be thinking about on different scales. But have you actually found any success stories where this hasn't hindered growth, which I think a lot of companies are worried about, it's just essentially a box ticking exercise, but we're actually helped the actual business on the commercial aspect.

A: Without a doubt. I think, firstly, it's probably important we need to recognize that we're in a quite fortunate position where Holcim our parent company are absolutely clear that the sector has to have a sustainable future. And without a sustainable future, there is simply no future for the sector because we've got to keep up and keep ahead and keep pace.

And that obviously filters down to Aggregate Industries UK level and our senior leadership team who are completely behind and support of what we do. So definitely in a fortunate position there, but we absolutely see it all the time from our customers are constantly asking us what we're doing around sustainability.

Want to be seen to be leaders with us something like having that clear intent and saying we want to be leaders in this space and we're pushing the boundaries in this space and we want to work with you. People soon want to come on that journey with you.

So, whilst it's always quite hard to quantify these numerous projects be that construction demolition material that we're reusing into projects in Canary Wharf in London through to our major road contracts where we're targeting more RAP in products through to customers who want low carbon concretes. This is all driving that message.

I think what I would say is it's a core base level, which everybody has to do. So everybody by now is really expected to have a net zero plan, perhaps not everybody does, but that's a given, and you expect that you're delivering on that.

Everybody is starting to think in some way about circularity and probably different levels of maturity. Everybody's environmentally compliant. The bit where you get that real business gain is that bit which is often quite hard to put tangibly and quantify, but it's when you go above and beyond.

So you do that next step. So that might be your New Stark putting carbon back into concrete. It might be a woodland that we've just been fortunate enough to plant at our Glensander quarry that links into all the local ecology and starts to do landscape restoration. This is what really gives you that added value and you soon find people start coming to you.

Q: That's awesome. And do your customers ever put on specific requirements for your products from an environmental standpoint and things?

A: Absolutely. So it might be from an environmental standpoint, it might be that part of the requirements of the lowest carbon option, and that might benchmark us against our competitors. It might be that they want a certain percentage of recycled material being a product.

We get asked about a lot and increasingly in the nature space. We're seeing customers start to come to us now trying to understand their nature impacts. We see this is a massively growing area. They want to know where they look back down their supply chain.

If you're building a big office block in the center of the city and you want to see your nature impact, you follow all your materials back down and you'll probably come to a load of aggregate and think, I wonder where that came from - it was a hole in the ground somewhere and they started to ask all those questions.

So, we want to be on the front foot and able to answer those questions before we're asked so we can be proactive and again show that real leadership.

Q: That just stands yourself apart, doesn't it? From all the competitors and they're asking, how are you guys stacking up against the other couple of main players with your sustainability goals?

A: Of course we would like to think that we're leading and that we're ahead of the game. I think what we try to do and hopefully is a key differentiator is we try to always have really clear, measurable targets. The carbon piece of decarbonization piece, people have clear measurable targets and that's got a uniform across, not just our key competitors, but across many industries.

But we're trying to constantly evolve and do that, and nature's probably the best example of this. We're the first in the sector to have a dedicated nature strategy that has not just set out an ambition and intent, but it also has quantifiable objectives and actions assigned to it that you can measure and track your progress.

And I think that's key in being a leader. You have to not just say, but you also have to be able to demonstrate and that needs to be quantified.

Q: You mentioned before about the biodiversity measures you guys are putting into place and everything. So could you talk a little bit more about that? You mentioned one of the quarries, you've set up a biodiversity initiative.

A: So biodiversity in nature is really important to Aggregate Industries and to myself at a personal level, which hopefully helps get some passion behind that and drive. So as I said, we've tried to make it proportional across the business, depending upon the scale and impact of the site.

So if we take our quarries and we look at biodiversity in nature, clearly they have both some impact, but also some of the biggest opportunities because we have often or sometimes decent land holdings around those quarries where we can do stuff above and beyond.

So if we take our Glensander quarry, we've just planted 105,000 trees or 64 hectares of native broadleaf woodland. So this is a really significant project and it all links into a wider piece in that part of Scotland where we're looking to reintroduce what we call the temperate rainforest. So this was all there many years ago and well before quarrying commenced and there was a lot of deer hunting and other things going on in that area, all the woodlands cleared. We now want to start to contribute towards putting that back.

Q: Amazing.

A: Of course, if you've got a ready mix plant in the centre of Glasgow, you don't have much opportunity to plant 64 hectares of woodland, but we want everybody to have some opportunity to do so we have something called places for nature where we want at least 200 of our sites by the end of next year to have a place for nature.

Now that can be anything from a bird box on the side of your office through to some wildflowers through to 105,000 trees.

We actually have found that it's been hugely positive because people, and if I'm openly honest, when we put it in, I thought, this sounds great and I would love this, but I'm not sure how well it's gonna land within the business.

But it's given people the opportunity to have some pride in their sides and create an area where they also want to be. Be that, they put benches in there and sit to have lunch. It's been amazing and it's landed really well.

Q: That's awesome. It's got to help just with the whole messaging and getting everyone on board. Just if they can actually see stuff that's going on on their local sites, see the improvements that it makes to their own life. And the nature around the area and what about the local communities and things, are you getting those guys engaged from surrounding the sites?

A: Absolutely so we can't do this in isolation, and we want to do this in conjunction with our local communities and local key stakeholders.

There's lots of examples. About 18 months ago, a quarry down south called Hill Head, we had a community initiative where there was a local environmental group who wanted to plant trees. So we gave them a corner of our site and local community group and local schools came in and planted a thousand trees.

I mean, and that's one example, but on a more broader scale, we're constantly wanting to engage and work with our local community. We've got a quarry called Little Paxton in Cambridgeshire, and that is a large sand and gravel quarry, and as we go we're doing what we call progressive restoration, so we're restoring it as we go and move into the next phase, and we work with a community group called the Friends of Paxton Pits.

And they're creating this nature, which is huge, and we're helping them do that as we go. But we're doing that in conjunction with the community to enable them to leave behind what they want and what they would like to see for nature.

The benefits of this are far reaching, not only can we deliver something that's incredible for nature and has the impact that the community wants, but it also helps us as an operator.

Paxton Pitts during COVID shut down for a bit, and the community were actually championing to have the quarry reopened because they want us to keep going, because they want to keep creating the nature reserves that come behind it. That's just an amazing legacy and collaborative approach to have.

Q: We'll have to link to those guys website or social media or whatever it is.

A: Most definitely. We've got a link. We've got a video, a Holcim video we made about 12 months ago, a part of which features Paxton Pierce. It's really, really amazing to watch.

Q: You guys have obviously been the leaders in your industry with regards to rolling out the sustainability plan. For any businesses that are just starting to take the first steps on this journey, whether they're big businesses, small businesses, high impact businesses, or low impact businesses, is there any particular advice you give to anyone who's just starting out on this journey?

A: Most definitely. There's a phrase I've got a bit hooked on at the moment, which is, "don't boil the ocean." I think first it's so easy to say, I just want to do everything. I need to do everything now. That's the natural instinct, but the best thing is to sit back and firstly work out what's materially important to you and your business.

Be that in terms of your impact or what do your customers also expect to see from you and then really focus your efforts down on those areas where it has the biggest benefit for both the sustainability perspective but for you as a business.

You talked earlier about how to get business buy in if it's important to business and your customers. That generally helps get your business buy in.

But at the same time, you need to engage the whole spectrum of the business. It's no good sitting in your sustainability team with a few senior managers and coming up with a plan that you think looks great if the guys on the ground and the ladies on the ground haven't been engaged in that.

So make sure that you have that full spectrum of business engaged in development and really buying into what you're doing. And that really helps it get legs and run.

Q: Thanks so much for your time today. And if anyone wants to connect with yourself or the business, anywhere in particular, they should have a look.

A: Yes. So I'm on LinkedIn. So I'm Tom Redfern, but I handle this T-Redfern. So feel free to add and drop me a message. Also, if you want to come drop us an email, sustainability@aggregate.com.

Q: Perfect. All right, we'll put the links to all of that below the video. Thanks again for your time, Tom. Much appreciated.

A: Thank you very much. It's been a pleasure.