The following organizations have provided funding for this Into the Outdoors television series.

What do you think is the greatest invention of all time?

Many would say it's the wheel.

This one idea revolutionized the world in immeasurable ways.

The wheel transformed travel and commerce, transportation, agriculture, engineering and industry.

Over time, the wheel evolved to function better and perform specialized uses.

Today, most wheels are equipped with tires, which make a smoother and safer ride and allow us to go further and faster.

But what happens when a tire is no longer usable?

Where does it go?

Hmm.

This seems like something for the adventure team to investigate as we head into the outdoors.

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In the US we just about one tire per person per year.

That adds up to about 300 million scrap tires.

Where do you think they go?

Tires are manufactured from vulcanized rubber with steel fibers woven through.

They're made to last a long time.

And they're not biodegradable.

So think about all those tires.

They're not just going to go away.

For decades, discarded ties were simply dropped off at landfills.

Many tires were dumped illegally in abandoned buildings along ditches in fields, lakes and rivers.

Maybe you've seen some of them.

Housing scrap tires aren't only ugly.

They also cause health and environmental hazards.

Michigan is the automobile capital of the world.

It is home to Detroit, also known as Motor City.

Communities here have been working with the state since 1991 to clean up over 35 million tires.

Maybe they can tell us more.

Michigan's known as the auto capital, which means we have a lot more tires than a lot of states.

And one thing that's very different in Michigan than a lot of other states is that we have a lot of urban dumping, tire piles that are placed in abandoned buildings.

A lot of the tires historically were just piled or dumped on property.

Those big piles of tires that residents didn't like to see them.

Sometimes there were tire fires, mosquito and rodent issues.

And so they started looking at solutions.

And in Michigan, part 169 was enacted in 1991 to start getting rid of the tire piles that were around Michigan.

In Michigan, you can't dispose of a whole tire in a landfill.

So we would require that a tire be at least cut into quarters or size reduced into chips.

But what we'd really like to see is this not be considered a waste, but be considered a reusable, recyclable material.

So this is an illegal site, unregulated collection site, we would call it.

They have more than 500 tires and they aren't registered with the state.

So what we're looking to do is determine how many tires are in that pile and what it's going to cost for the state to clean it up.

So in Michigan, we're funded by a fee on a vehicle title transfer that's collected by the secretary of state.

The clean up grant program here in Michigan has already cleaned up more than 35 million tires in the state to date, and we clean up approximately 750000 to 1000000 a year.

Even though these tires look like waste, there's a huge potential for this material to turn into a reused, recycled material and help solve some of the problems that we are experiencing with our infrastructure.

Scrap tires pose a problem across the US, but each state manages to regulate their waste differently based on their needs.

The size of the state, its population, its resources and the quantity of waste.

Some states, like Colorado, collect scrap tires, which can then be managed and distributed for other uses.

Let's see what happens to scrap tires in Colorado.

Here in Colorado, in the past, we did not have great rules or regulations in place to properly manage scrap tires.

In Colorado, we still have issues with illegal dumping.

Normally this happens in rural areas or properties where the scrap tires are not easily detected.

There are a couple of concerns that we have when tires are illegally dumped or stored.

One of them is fire.

When a tire catches on fire, it releases a lot of hazardous chemicals, can cause black smoke and they could burn for a very long time.

Another way is they collect rainwater, which breeds mosquitoes.

They can cause West Nile disease.

So finding ways to manage it properly greatly reduces the risk of this to both the people and the environment.

Our goal is that every scrap tire that's generated in the state goes towards recycling into some type of tire product.

Anyone that's handling scrap tires has to be registered with the state of Colorado.

That includes any tire shop, anyone that's hauling those waste tires, and anyone who's to process and recycle them into different products or ultimately may be disposing of them into a monofill.

A monofill is a landfill that only accepts scrap tires.

These monofills are scheduled to be closed in the near future.

And so we need to find ways to continue to take scrap tires, recycle them and turn them into beneficial products.

In Colorado, we've recycled millions of tires over the course of several years, sometimes even over 100%, which means that we're actually taking tires, out of our inventories as some of the monofills.

The great news is a lot of these scrap tires are being created into new tire products.

Reduce, reuse, recycle.

How can we reduce the number of scrap tires, practice good tire maintenance, keep the proper air pressure in your tires, keep them balanced and rotate tires as recommended by the manufacturer.

Can you think of any sustainable solutions or ways to reuse or recycle scrap tires?

What makes something a waste material?

That really depends on whether the material has value or beneficial use.

If it can be used, it's actually considered a resource or product.

Are scrap tires a waste material?

One of our adventure team members visited first state tire recycling in Minnesota.

Let's catch up with Wesley and see what he learned about recycling tires.

Meet Monte Niemi, an entrepreneur and business owner who has been working in the scrap tire business for 40 years.

In 1984, when the Minnesota state legislature mandated that tires had to be recycled, Monte got creative and began thinking of alternate uses and products.

For scrap tires.

His company began to manufacture a product called tire derived aggregate or TDA.

There's so many tires here.

Can you tell me what you do with all them?

Sure.

Here at first tire, we take old tires.

Tires that still have life as a little bit left on it.

For a spare tire, for good, usable tires.

We try to find the highest and best use for those tires.

So here, every day we get about 10 to 12000 tires in our facility that we unload.

See our guys are unloading our trucks.

They're deciding if these are good tires that can be reused or if they're bad tires to go to the shredder to become TDA.

So here we're looking at our grading station.

He's inspecting the tire to make sure that it has no defects.

It's roadworthy and it's going to pass a dot inspection.

The tires that no longer have life as a tire shape on our vehicles.

We send that to making tire derived aggregate through our machinery.

What is tire derived aggregate?

Tire derived aggregate, also known as TDA, is a material produced from old tires.

It gets processed into a material that engineers can use in their construction projects.

If we make tire derived aggregate by running it through a couple of piece of equipment, some slow speed shearing shredders, cut the tires into strips, and then those strips are cut a second time and they end up in about three by five, five by seven inch piece of material under 12 inches.

There is no waste stream.

Everything is reused either as a good, usable tire or as into making tire derived aggregate.

There's no waste byproducts.

Do you even know how many tires you get every year?

For the last 30 years, over 2 million tires a year.

So over 60 million tires have gone through this process.

And have been reused on these type of engineering projects.

That makes a huge difference in the waste tires.

It has really made a huge difference in the Midwest.

Here we have no waste tire problems here because all the waste tires are finding their way to a facility where they're being reused or repurposed in this tire derived aggregate.

Some parts of our nation have big waste tire problems, so they have big stockpiles.

Here in the Midwest, we don't have any problems like that at all.

Let's check out some of the ways TDA has been used.

Tire derived aggregate was used on this apartment construction site in Burnsville, Minnesota.

Engineers needed a lightweight material to reduce the lateral pressure against the wall of the underground parking structure.

In this project here, because it's a two story underground apartment complex, we're backfilled up to a certain level, and then we're using a ten foot tire section to take the pressure off of the wall.

Tire shreds weigh 600 pounds a cubic yard, loose volume soil weighs 3,000 pounds per cubic yard.

So we have a lot less overall weight on this material.

Tire derived aggregate has very little lateral loading or side pressure against the building where material basically stands vertical while soil has a cone effect where it ends up putting substantial lateral loading.

And any rain that comes through the soil that works its way towards the building once it hits the TDA well, right down to the drain pile.

So that water will never hit the building itself.

In this particular project, we used over a thousand cubic yards of tire derived aggregate.

That would equate to about 35,000 discarded tires.

So that's quite a few tires in this one little project we're using up.

We're in Eden Prairie, Minnesota, today.

Back in the 1990s, the community wanted to accent this beautiful lake and pond we have behind us here.

But unfortunately, the area they wanted to put a park was nothing but a swamp or a marsh and very, very difficult to build on.

If they would have put normal soils on top of it, it would have squished out all over the place.

So they had to come up with a lightweight material.

They ended up choosing tire derived aggregate because it's sustainable and only 600 pounds per cubic yard.

Here in this park, there is between three and six feet of tire derived aggregate underneath the soil and landscaping.

Overall, we used 30,000 cubic yards of tire derived aggregate, which equates to approximately a million passenger tires.

This exit ramp is another example of how TDA solved an engineering problem.

We are standing at the location of Exit 171 off Interstate 35 near Pine City, Minnesota.

This is the location of the first TDA project that was used on the interstate highway that we know of.

So we had a problem originally.

The ramp that was built here using conventional construction methods failed.

It actually slipped and sunk into the organic soils underneath.

And rather than removing all of that soil and replacing it with rock and gravel at very high expense, we use tire derived aggregates by using tire derived aggregate, we've been able to restore that use of that ramp.

It's almost 30 years later and the ramp is still functioning very well.

TDA has characteristics that are beneficial for engineering use in roads, backfill, drainage, stormwater, etc.

Primarily, it's because it drains water extremely well and it has the ability to link together in the pieces and they actually will float on the organic soils to provide strength and stability both to the highway above it as well as the movement of water.

So we minimize or reduce the freezing and thawing cycles that many roads in northern states have in the US.

That is a great use of a waste material.

I'm here at the Minneapolis Convention Center, standing in a beautiful urban meadow.

But did you know that under the topsoil there's 2500 cubic yards of tire derived aggregate?

Can you tell me why TDA was used for this project?

Sure.

We're actually standing on top of a parking garage.

They were designing it to have this nice urban meadow on top of it, but they didn't want to overbuild the structure in order to support all the soil that they had to put up here.

So they were looking for a lightweight material that had good drainage properties.

TDA weighs about 20% of what traditional fill like soil or gravel would weigh.

TDA is the perfect solution here.

What are some of the benefits of using TDA?

Oh, don't get me started.

There are a lot of benefits to using this material as a geotechnical material.

It's very durable, it's very lightweight.

It has great porosity or permeability, so water runs right through it.

It's a material that has great insulating properties, good vibration containing properties.

You can use it to drain so that you don't get frost heave.

And it's really inexpensive because it's a waste material that we're repurposing.

This is such an amazing place.

It's a great example of how an ugly problem like scrap tires can be turned into a beautiful place for the community to enjoy.

Never underestimate a good idea.

Sometimes when you're searching for a solution, you might find the answer to a problem you didn't even know existed.

That's exactly the case for tired derived aggregate, which is proving to be a good solution for stormwater management.

Back to you, Wessly.

This is the Midway Business Park.

Once a contaminated property or brownfield, the Saint Paul Port Authority wanted to turn this land into a safe place for commercial offices, but they needed a smart way to collect and filter stormwater.

This is the former Midway Stadium site, home of the Saint Paul Saints, for many years.

Prior to that, it was also known as state fair dump.

Over the years, contamination was brought and dumped on the site.

At the Port Authority.

We thought it was a prime opportunity to clean up what we call a brownfield, which is a contaminated or perceived to be contaminated site that suffers from a lack of investment.

Once the site was cleaned up, we needed to build the infrastructure to serve this building.

It's about 12 acre site.

It's nearly all impervious.

So that meant we had to collect a lot of rainwater and figure out what to do with it.

An environmentally sensitive manner.

Couldn't it just run into the streets?

It could.

For many years.

That's how we dealt with stormwater.

We treated stormwater as a waste product.

The stormwater running across the street picks up contaminants, particles, pollutants and flushes them all basically down the Mississippi River.

And that might cause flooding down river.

So we had to figure out a way to use rainwater as a resource by capturing it and holding it onsite and allowing it to infiltrate back into the aquifer.

So how did you solve this problem?

Well, we are collecting all of the rainwater on the 12 acre impervious site and channeling it to this parking lot underneath this parking lot.

There is a gigantic seam of sand and an infiltration base that collects and stores the rainwater long enough to allow it to sink back into the ground.

When we dug the Infiltration Basin, we had to fill it back up with something to support this parking lot.

The solution we used was tire derived aggregate shredded tires that otherwise would have gone to a landfill as a waste product.

They were a very cost effective solution, had the necessary void space to handle the massive amount of runoff coming off all of this impervious surface on the site and was a great solution for this system Here's the amazing thing.

Tire derived aggregate has environmental benefits that we didn't even know about.

Researchers from the University of Minnesota have been studying TDA at the Saint Anthony Falls Laboratory.

What they've discovered is that this material can actually help remove pollutants from stormwater runoff.

We're at Saint Anthony Falls Laboratory.

We're in Minneapolis on the banks of the Mississippi River.

And we study rivers, water, wind and waves, climate change.

But we also study stormwater pollutants and runoff and try to keep clean water in our environment.

What do you mean by storm water?

Stormwater comes from rainfall.

So when the rain falls on our urban landscapes, it runs off our rooftops and our driveways and our roadways and it picks up pollutants.

That water doesn't go to the treatment plant.

It actually goes almost directly to our rivers and our lakes.

So we need to treat it before it gets there to keep our water clean.

A big concern in Minnesota and a lot of the US is phosphorus because it can cause harmful algal blooms.

So we're studying phosphorus with tire derived aggregate, but we're also studying metals and other things that could be coming out of the tires.

Can you tell me why you were studying scrap tires?

Yes, there are companies that are using scrap tires in their construction projects and even in their stormwater treatment practices.

We're studying it because we want to know, are there any harmful consequences or potentially are there any benefits to the environment?

Kidney scrap tires clean the water.

We've discovered some very interesting things.

These tires can be used in these construction projects, and when they soak in the water, there's actually a biofilm that grows on the surface of the tires, kind of feels slimy or like a sludge on the outside.

But it's actually tiny microbes and they're growing there and they can actually remove pollutants from the water and really produce cleaner water coming out of these systems.

That's cool.

Yeah.

Tell me, how do you test the water?

We take these shredded tires, this tire derived aggregate, and we put it in containers and soak it in water for a long period of time.

So what we're doing now is we're actually collecting samples from our experiments.

So we're going to draw water out of these buckets that contain shredded tires and water, in this case, river water.

And we want to understand what's in the water so that we can see what is being removed by that biofilm that we talked about earlier.

What Rajneesh is looking at here is we have this top row of buckets is all river water.

It's natural water out of the river.

And we're looking at how the shredded tires interact with that water.

And then these other two shelves are actually holding what we call synthetic stormwater.

And that's water that we take.

And we put in a specific amount of pollutants to represent stormwater runoff things like by carbonate and chloride to get the electrical conductivity and the alkalinity correct and other things to really mimic stormwater and also promote the.

Growth of that biofilm.

So what I see is tire derived aggregates benefits and we reduce how many tires are going into landfills.

But more importantly, the tire derived aggregate actually can remove pollutants from stormwater runoff and actually produce cleaner water for the environment.

Not only does TDA help reduce waste and solve engineering issues.

It can actually help clean our environment.

Now, that's a smart idea.

Humans are excellent.

Problem solvers in creativity may maybe our best asset.

Can you think of any other innovative ways to use scrap tires?

Many states offer incentives, rebates and grants to companies that process and utilize scrap materials.

Michigan is one of several states using scrap tires as rubber modified asphalt, proving to be an effective road covering for areas that have frost heating or extreme temperatures.

There are several companies that process scrap tires, shredding them into various sized pieces for different uses.

Some can even extract the steel fibers woven into tires.

Entech in Indiana specializes in making mechanized and crumb rubber from old and new products.

They also smelt the steel fibers to create steel ingots.

So here at Cobalt, we make different sizes of crumb rubber and we make a rubber mulch.

The rubber mulch, we use that for landscaping.

Some of the crumb rubber sizes that we make, you can put on a football field for Astroturf.

They also use it in injection molding and other material.

30 minus.

It's used in applications with rubberized asphalt.

It helps with the expanding and contracting of the asphalt itself.

So you don't have near as many cracks to help the roads last a little bit longer.

Cobalt Holdings in a day can process anywhere up to 67,000 pounds of tires, and in a year we do 14 million pounds.

We make a difference one tire at a time, by shredding just four tires, we cut back on CO2 by 323 pounds which in turn equals 18 gallons of gasoline.

Porous pave in Michigan uses rubber chips for their innovative product.

Porous pave is a unique material made of recycled tires, a stone aggregate, and then a proprietary urethane binder.

Those are mixed together and put down similar to concrete.

It hardens and gives you a durable surface, yet lets the water drain through it.

We contract with different shredders around the United States to grind up the material for us.

Rubber has great traction, whether it's wet or dry, it's a great product to use, especially if it's a slope or an angle.

It's porous.

Lets a lot of water drain through it.

It's also flexible, can expand and contract and move with the ground as it freezes and thaws without cracking.

Porous paving gets installed in a wide variety of applications.

A lot of our work is city and municipal type work, walking trails and paths.

A lot of tree surrounds in cities, do a lot of work on universities or trails and walkways on campuses.

We also do a lot of residential type work patios, fire pits, different areas like that in residential applications as well.

At this point we've installed over 5 million square feet and we've recycled over 20 million pounds of scrap tires, thousands and thousands of tires that otherwise would have ended up in a landfill.

Feels good to be solving problems in applications, but also preventing all those tires ended up being a waste.

In Colorado, the number one reuse of scrap tires is as a fuel source.

The tires in this monofill are used to create tired derived fuel, or TDF.

It's an alternative to burning fossil fuels and produces 25% more energy than coal.

It also provides necessary raw ingredients for cement manufacturing.

So here at Colorado Energy Recyclers, we do two things.

We receive fresh tires from the market.

Those get dumped off at our shredder and get shredded instantly.

We also run a monofill, which we pull tires out of.

We have a big loader with the grapple that picks tires out of the pits and takes them up and dumps them near the shredder.

The shredder we use makes a product that really works well with our kiln system, pulls out some of the wire, but about 30% or so stays in there.

It's actually a raw material that we utilize in our cement making process.

The tires that you've seen processed at the monofill will land at our cement plant where they're dumped off into a hopper feeder and they'll go up the system and be used in our pre calcined system.

So TDF is the number one re-use of scrap tire material in Colorado for the process of making cement requires very, very high temps.

We're talking 3400 degrees Fahrenheit.

Normally, we used to use coal.

The TDF that we started utilizing actually gives a better BTU value as it's higher than the coals.

It helps us reach those temps at a quicker rate in each day, and it's usually around 50 to 60 tons of tires that we burn here at the cement facility.

It's awesome to be able to utilize materials that were considered waste and use them as an energy source and take them out of these landfills.

When you see a problem, maybe something that feels too big to solve, do you ignore it or try to find a way to make a difference?

Well, that's the story behind Pretread a company based in Aurora, Colorado.

One day I was fly fishing in a local creek in Colorado.

I looked over on the side of the bank because I was fly fishing and I noticed a large pile of tires and some plastics in it.

And I thought of my daughter, my daughter's future, how the environment and how people are going to be affected by these waste products.

The engineer in me looked at these raw tires and plastics sitting on the bank and wondered, There's got to be something we can do with this waste stream, something we can do to help our generation be able to handle this better.

And that's how we came up with retread.

We turn scrap tires that you use every day into large industrial, sustainable barriers and blocks for things such as parking lots, flood control, rockfall, mudslide, roadway and more.

Our products are fully sustainable closed loop.

And what that means is that we can take a recycled material, turn it into a new product, and when that product is damaged or worn out, we can turn it back into itself.

Each pretreated barrier product removes about 60 to 75 tires from our local landfills and dumps.

That's a pretty significant impact when you start talking making miles and miles of free trade barriers.

We're making a difference.

Sometimes environmental issues feel like mountains, but with creative ideas and working together, we can make a difference.

If we can find a sustainable solution for material like tires.

What other environmental solutions can we come up with?

(music) “Grab your gear and” “Lets explore.” “As we discover” “The wild outdoors.” “Science.

Discovery.” “Is what we do.” “You can make our Earth.” “A bright and better planet.” “By joining us.” “In this wide open space.” “Into the Outdoors.” The following organizations have provided funding for this Into the Outdoors television series.