Iss2/Ch1 Dam you straight to h*ck

This issue is all about the green energy transition, or replacing fossil fuels with carbon-free sources of energy. What is the best way to generate green energy? How much green energy can we generate? How fast can we make the transition?

In Chapter 1, we will start with a side-by-side comparison of the leading candidates for generating electricity without fossil fuels: nuclear, wind, and solar. Just for fun, we’ll throw in geothermal, which gets very little attention but is technically a potential source of green energy.

To determine the best form of green energy, we’ll look at the most important factors for a green energy transition. For example, are all of our candidates renewable – that is, impossible to exhaust as a source of energy? Are there any barriers to immediate large-scale implementation?

We’ll start with the most basic question: can each of our green energy candidates fully phase out fossil fuels?

Green energy duel #1: Can it phase out fossil fuels?

All of our green energy candidates require extremely high temperatures to manufacture. Solar panels need glass, and glass requires temperatures of over 2400 degrees F to manufacture. Nuclear, wind, and geothermal plants all need cement, which requires temperatures of over 2500 degrees F. All four of our candidates need steel, which requires temperatures of up to 3000 degrees F.

In other words, all of our green energy candidates require industrial heat. Unfortunately, we currently do not have a way of producing such high temperatures at an industrial scale except by burning fossil fuels (eg), and scientists have no plausible ideas for replacing glass, cement, or steel with equivalents that do not require industrial heat to manufacture. Fossil fuels are advantageous in this respect because they are, literally, a fuel. If burned in a power plant, they generate electricity; if burned in a blast furnace, they generate industrial heat. By contrast, none of our green energy candidates can function as a fuel: they can only generate electricity. The challenge, then, is to find a way to generate high industrial temperatures using electricity.

If we do not figure out a way to generate industrial heat via electricity, then none of our green energy candidates can be built without fossil fuels. This puts humanity in an extraordinary danger. Solar panels only last 30-35 years, wind turbines 20 years, nuclear plants 60-80 years, and geothermal plants 60-100 years. None of our candidates lasts forever, and we are currently unable to replace them without burning fossil fuels. Unless we figure out a way to generate high temperatures at an industrial scale, our green energy transition will start to unravel in 20 years, when our first wind turbines need to be retired, and wholly collapse within a century, when the last geothermal power plants reach the end of their useful lifetime.

One promising idea for fossil-fuel-free industrial heat is the electric arc furnace, which can generate very high temperatures using electricity. Electric arc furnaces have already been used successfully in recycling scrap steel, but that process nonetheless relies on fossil fuels to preheat the steel. Electric arc furnaces have not been successfully implemented for producing new steel, nor for glass or cement. Another promising approach is so-called “green hydrogen,” wherein electricity is used to split water into hydrogen and oxygen. When burned, hydrogen and oxygen generate high industrial temperatures. The underlying chemical reaction is straightforward, but green hydrogen has not been successfully implemented at an industrial scale. The major problem is that splitting water is extremely energy-intensive; in other words, we would have to build out extra gigawatts of electricity generation capacity for there to be enough electricity for all the green hydrogen needed to build replacements for our solar panels, wind turbines, and nuclear and geothermal power plants as they wear out. Other ideas, like using chemistry to turn agricultural products into a form that can generate high temperatures when burned, would also be extremely energy-intensive.

Aside from the steel and concrete of the power plant itself, geothermal has an additional need for fossil fuels: to dig to the necessary depths, the horsepower of fossil fuel-powered drills is required. Electric options simply don’t have the necessary power. In theory, electric equipment should be powerful enough to maintain holes dug by fossil fuel-powered machinery, but this is not certain.

It’s worth pausing to reemphasize what extraordinary danger we are in. With the collapse of civilization imminent, why are we not devoting more resources to finding a carbon-free source of high industrial temperatures? The irresponsibility of policymakers from the past is stark. Had policymakers taken climate change seriously in the 1980s, this problem could have been avoided altogether using the concept of a carbon budget, or the amount of fossil fuels that can be burned without triggering dangerous climate change. We could have budgeted enough fossil fuels to be able to indefinitely replace our solar panels, wind turbines, nuclear plants, and geothermal stations as needed. Instead, we blew through our carbon budget with wars of choice and private jets.

So far, not great: none of our candidates can actually phase out fossil fuels – at least within the bounds of existing technology.

Next, we’ll consider the all-important question of whether each form of energy can serve humanity as long as humanity is around.

Green energy duel #2: Is it truly renewable?

A source of energy is renewable if it cannot be exhausted. Our ideal green energy must be renewable because if we ever exhaust our capacity to make electricity, civilization will collapse.

Fossil fuels are not renewable – once all the oil, gas, and coal the planet has to offer has been extracted, it will take hundreds of millions of years to regenerate. Of course, if we actually used up all of Earth’s fossil fuels, it would trigger climate change so severe that the planet would become unlivable before that point.

By contrast, wind and solar energy are endlessly renewable. As long as humanity might be around, the sun will shine and the wind will blow.

Like fossil fuels, nuclear is not renewable. Nuclear power plants run on uranium, #92 on the periodic table. However, nuclear energy can only run on a rare form of uranium – uranium 235 (92 protons and 143 neutrons) – which is 142 times less abundant than uranium 238 (92 protons and 146 neutrons). There is no natural or human-made process to replace uranium 235: once we use up all the world’s mineable uranium, it’s gone forever.

Just because nuclear is not renewable does not mean it can’t be an important part of a green energy transition. Nuclear power plants generate no greenhouse gases. Perhaps nuclear power is a useful, if limited, resource? According to energy experts:

In 2015, world electricity consumption was around 24,000 TWh/a. Assuming no rise in electricity demand and ignoring non-electric energy consumption such as transport and heating, uranium resources of 7.6 million tonnes will last 13 years.

In other words, Earth’s uranium resources are actually quite limited. Even decommissioning all of humanity’s nuclear warheads and using the uranium they contain to generate electricity would not extend our ability to use nuclear energy very far: All of the active warheads in the US arsenal (probably about a third of the US’s total arsenal) would be able to power the city of Los Angeles for 7.8 years.

There are tantalizing alternatives. An experimental power plant using thorium instead of uranium produced 2.1 terawatt-hours of electricity for consumers in the Pittsburgh area in the 1970s. Among several other advantages, there is enough thorium to meet all of humanity’s energy needs for at least 2000 years, and unlike uranium, thorium does not generate any dangerous radioactive waste. Meanwhile, a totally different type of nuclear reaction – nuclear fusion – would be fully renewable – capable of meeting all of humanity’s energy needs forever – and generate zero waste. While scientists have been able to make the nuclear fusion reaction work in a laboratory, they have not been able harness the energy of the reaction to generate electricity. Though a longshot, it is likely that nuclear fusion is possible with sufficient investment; the prospect of an inexhaustible source of energy with zero waste certainly warrants generous funding. We consider these and other ideas – like using uranium 238 as fuel, which would meet humanity’s energy needs for more than 2000 years – in our bonus chapter, What the $%&! were we thinking? Green energy tech we never developed.

Overall, the fact that nuclear is not renewable seems to eliminate nuclear from contention. At best, we can meet the planet’s energy needs for a couple of decades before exhausting all of Earth’s uranium 235. But as this issue’s introduction alluded to, the story isn’t so simple. Our green energy duel continues.

Finally, before moving on, we’ll consider our also-ran, geothermal. Like wind and solar, geothermal is renewable. Geothermal energy uses heat from inside Earth to generate electricity. A common misconception is that geothermal plants tap into the heat of Earth’s core. As we learned in elementary school, most of Earth (the mantle and core) is extremely hot and consists of molten rock: we live on the outermost layer of Earth (the crust) that has cooled and solidified.

The reality, however, is more dynamic. Earth’s center isn’t simply a molten hot ball slowly cooling off; instead, it’s full of radioactive atoms undergoing their natural decay process (change into a more stable atom), which releases a large amount of heat. Additionally, heat from Earth’s core is continually radiating outward from its hot center, through the crust, and out into space. In this way, Earth’s center loses heat through radiation, but also regenerates that heat via radioactivity. The idea behind geothermal energy is to harness the heat continually flowing out of Earth. Geothermal is thus renewable because it harvests Earth’s heat that was on its way out to outer space anyway. (In Bonus Chapter 1, What the $%&! were we thinking? Green energy tech we never developed, we consider ideas for geothermal energy that would harvest more).

In sum, solar, wind, and geothermal are all renewable. Nuclear is not, and – absent miraculous technological advances – can only meet our electricity demand for less than two decades.

Next up in our duel: physical space requirements.

Green energy duel #3: What’s the footprint?

Because an individual wind turbine and solar panel generate little electricity relative to a nuclear or geothermal plant, wind and solar take up an enormous amount of space. MIT’s Climate Portal estimates that a single nuclear power plant produces as much electricity as 800 wind turbines or 8.5 million solar panels. We won’t spend a great deal of time on this problem because it is solvable; rather, this section is to highlight the ecological catastrophes that can result if we don’t take this problem seriously.

For an extreme example, the Ivanpah Solar Power Plant blanketed 5 square miles of the Mojave Desert with solar panels. The area is home to dozens of different species of flora and fauna, but the desert tortoise was of special concern for two reasons. First, desert tortoises are critically endangered. Second, they are a “keystone” species, or one that much of the ecosystem relies on. Specifically, desert tortoise burrows provide essential shelter for other species once the tortoises move on. If the desert tortoise goes extinct, other animals would surely become endangered as they would be unable to find shelter.

Owing to their ecological importance, $50 million was spent to try to save desert tortoises from the construction. One biologist employed to rescue tortoises told a reporter,

When you’re walking in front of a bulldozer, crying, and moving animals and cacti out of the way, it’s hard to think that the project is a good idea.

Just three years later, the majority of the “rescued” tortoises were dead (they normally live 70-80 years). Similarly, arraying so many solar panels so close together at an industrial scale has led to the deaths of thousands of birds as they literally start on fire mid-flight. Clearly, the massive physical footprint of solar energy can devastate ecosystems.

Wind turbines have a similar problem. So many roads and so much construction material are needed that a wind farm cannot be situated in a natural area without destroying it. The issue of birds, including critically endangered birds, being killed by wind turbines, remains unresolved. 

Ivanpah and other examples are often used by fossil fuel apologists as cautionary tales, highlighting the irony of “saving the planet” with green energy while wiping out sensitive ecosystems. In reality, this problem has been solved. First, solar panels do not have to be arranged in giant, ecologically destructive farms like Ivanpah. Solar panels can be installed on the roofs of existing buildings. Rooftop solar is about double the cost per kilowatt hour as solar farms, but because rooftop solar is more efficient and has none of the severe ecological drawbacks, it is well worth the added cost. Similarly, certain crops actually grow better in the shade. Thus, situating solar panels on existing agricultural fields also avoids the severe ecological impact while improving crop yields. To minimize ecological harm, wind farms, too, can be placed on existing agricultural fields and away from bird migratory routes, and scientists are exploring ways to make wind turbines more noticeable to birds so they know to avoid them.

So, while the large footprint of wind and solar is a problem, it can be solved with careful planning: we can install wind turbines in agricultural fields that offer the most efficient, cost-effective, and lowest ecological cost, and we can install solar panels on the most cost-effective and efficient roofs. To get this right, it’s critical that these decisions be based on science and evidence, not decided by the free market (which has already turned the rooftop solar market into a cesspool of fraud and abuse).

In sum, nuclear has a small footprint because so much energy is contained in a small amount of uranium: a single nuclear power plant can generate as much electricity as 800 wind turbines or 8.5 million solar panels. Geothermal, too, has a small footprint because most of the construction is underground. While wind and solar are the clear losers in this category, all of wind and solar’s footprint problems can be solved with careful planning.

Green energy duel #4: What about storage?

Storage is one of the most vexing issues of the green energy transition. Fossil fuels’ greatest advantage is that fossil fuel power plants are dispatchable – that is, they can be quickly turned up or down according to the demand for energy. None of our candidates is dispatchable, so we need a technological workaround.

For wind and solar, the issue is intermittency: if it’s not windy or sunny, electricity generation is impossible. Thus, wind and solar operations must generate substantially more electricity than is needed when the wind is blowing and the sun is shining, and somehow store that extra electricity for use when it’s not windy or sunny.

Nuclear and geothermal are not intermittent, but they have a similar problem. They are what’s known as baseload: once up and running, they provide a steady amount of electricity with very high reliability, but they can’t be turned up or down according to demand. This is a problem because energy use is typically higher during the day and lower at night when everyone is asleep. Thus, nuclear and geothermal would have to produce extra electricity at night and store it for use during the day.

Because nuclear and geothermal are so consistent, far less energy storage is required than for wind and solar. In other words, while the need for electricity storage is a disadvantage for all four, it is a far, far more serious problem for wind and solar. In the bonus chapter What the $%&! were we thinking? Green Energy tech we never developed, we will explore a type of geothermal under development that could be turned down at night and up during the day, nearly eliminating the storage problem. Unlike the other topics in that bonus chapter, this remarkable new technology is close to ready for large-scale implementation.

In sum, all four of our green energy candidates need storage to avoid daily blackouts, though wind and solar need more than nuclear or geothermal. But how can large amounts of electricity be stored?

Storage is a serious issue because it requires a great deal of resources, including mined natural resources. Electricity can be stored in gigantic, utility-scale batteries, and these require an extraordinary amount of minerals and other resources. According to the International Energy Agency (IEA; p105), in 2020, 26,000 tons of various minerals such as nickel, lithium, and cobalt were required to meet green energy storage needs. In order to meet the energy storage needs of a full green energy transition, the IEA estimates that by 2040, annual mineral requirements will be a whopping 850,000 tons for utility storage alone.

That being said, combining green energy with utility-scale batteries has proven viable in the real world (eg). The issue isn’t that the technology can’t work; it’s that because all of our green energy candidates are either intermittent (wind and solar) or baseload (geothermal and nuclear), green energy requires additional resources that fossil fuels do not.

This leads us into the next topic – resource use.

Green energy duel #5: What about resource use?

As mentioned in the footprint section, an individual wind turbine or solar panel generates very little electricity relative to a nuclear or geothermal plant. Thus, with the need to build so many solar panels and wind turbines, far more resources are needed to generate the same amount of electricity.

How much more? To generate a terawatt hour of electricity (Table 10.4), nuclear power plants require 760 tons of concrete versus 8,000 tons for wind. Nuclear requires 160 tons of steel per terawatt of electricity; wind requires 1,800 tons, and solar 7,900 tons. Nuclear requires no glass; wind requires 92 tons of glass per terawatt of electricity, and solar, 2,700 tons. For the major inputs – concrete, steel, glass – nuclear requires about a tenth or less of the resources needed by wind and solar. Geothermal lands somewhere in the middle, requiring 1,100 tons of concrete, 3,300 tons of steel, and no glass to generate a terawatt hour of electricity. Wind also requires an extraordinary amount of rare earths, a crucial issue we will consider in detail in Chapter 2.

At this point, you might start doubting the usefulness of our green energy duel, particularly if you follow green energy news. Wind and solar require substantially more resources to generate electricity, yet, as discussed in the previous section, all of our candidates require utility-scale batteries for energy storage to prevent blackouts. In other words, by considering only how electricity is generated, we are missing a big part of the picture. That’s particularly true because none of our green energy candidates require much, if any, of the critical minerals of the green energy transition, like lithium, cobalt, nickel, and rare earths. But, utility-scale batteries need them. Clearly, by only considering electricity generation, our green energy duel ignores some crucial parts of  the green energy transition.

Taking this logic a step further, utility-scale batteries do not alone account for the massive need for minerals of a green energy transition. As discussed above, the IEA estimates that 850,000 tons of minerals will be needed annually for utility-scale batteries. But the IEA also estimates that at least eight times that amount will be needed for electric car batteries (p89; the light and dark blue bars are electric cars and the orange is utility batteries). And that’s only for the batteries; electric car motors also require an enormous amount of minerals outside of the battery (see p88-89).

The biggest consumer of both mineral resources and electricity in a green energy transition will be electric cars, which we consider in greater detail in Chapter 3. Overall, electric cars require an astonishing six times the mineral inputs of a gasoline-powered car. Primarily, the resource needs are for the motor, battery, and wiring. A single electric car uses 44 pounds of cobalt, 20 pounds of lithium, 110 pounds of nickel, and 117 pounds of copper. Swapping out each gasoline-powered car for an electric equivalent would thus require a mind-boggling amount of resources. A fleet of electric cars will also require an eye-popping amount of electricity to keep them charged. If the US replaced each gasoline-powered car with an electric car, it is estimated that electric cars alone would require just for themselves as much electricity as the US currently generates. In other words, to keep all of our electric cars charged up and running as part of a green transition, we’d need to replace all of the fossil fuel power plants generating electricity – that’s nearly all of our electricity currently – with green energy. That will take care of electric cars. Then, we’d have to double our electricity generation to run everything else that uses electricity at current levels (like cooking, heating, lighting, hospitals, computers, etc). Then, we would have to generate even more electricity to run other fossil fuel conversions – for example, replacing diesel trains with electric trains, replacing gas-powered furnaces and stoves with electric options, etc.

This is, to say the least, an unimaginable amount of work and resources, and as we near the end of our green energy duel, it is becoming clear how limited this exercise really is.

By jumping directly to the question of “what is the best way to generate green energy?”, we have skipped more fundamental questions. Questions like: do we need all the energy we currently use? Do we need green energy replacements for everything currently running on fossil fuels, or is there a more efficient way to maintain our high quality of life with less energy? These questions must necessarily focus on cars because electric cars will consume the bulk of the resources and energy of a green energy transition. No other part of the green energy transition is as resource- and energy-intensive.

This will become extremely important when we face the last challenge of our green energy duel – waste. But first, we must consider the state of green energy technology.

Green energy duel #6: Is it shovel-ready?

We added geothermal to our duel for fun as an also-ran, but after a side-by-side comparison with other green energy options, it certainly appears to be the best option. It is fully renewable, has lower storage and resource requirements, has a small footprint, and – as we’ll see below – generates the least amount of waste.

The problem with geothermal is that not all of the technology has been developed. While astonishing technological advances have been made in solar and wind power in the past decade, and efficiency is expected to continue to improve, geothermal’s technological problems are more acute. Let’s start with the technology that does exist and is fully shovel-ready (meaning it can be implemented at a large scale today).

Shovel-ready geothermal technology

Traditional geothermal can only be used in certain parts of the world where geological conditions are right. Nonetheless, this is a vastly underused resource. According to geothermal expert William Glassley, 14.7 megawatts of electricity, or a quarter of the world’s current electricity use, could be generated using traditional geothermal methods.

However, substantially more electricity could be produced using newer technologies that can operate at far lower temperatures. Traditional geothermal can only function if the ground is hot enough to boil water: boiling water pushes the turbines that generate electricity (imagine a pot of water at a rolling boil; the force of the steam moving upward is enough to make the lid of the pot rattle, and enough steam can push giant turbines to generate electricity).

But newer technology, known as binary geothermal, can operate at lower temperatures, thus greatly expanding the places where geothermal can be installed. Binary geothermal plants heat water and then use the hot water to boil isopentene, a liquid with a much lower boiling point. Once boiling, the isopentene rises and turns the turbines to generate electricity. Binary geothermal can generate ten- to twenty times as much electricity using the same amount of heat as traditional geothermal, primarily because isopentene’s boiling point is so much lower than water: a much smaller amount of heat is needed to boil it. In sum, there is massive, untapped potential to use geothermal to meet our electricity needs using shovel-ready technology.

But geothermal could be even more widely used in any part of the world for applications that require constant, warm (but not hot) temperatures. Writing in 2010, Grassley points out that geothermal has already been used with success in providing heat for industrial applications, including fish farming for over two dozen types of fish, as well as for drying several different types of food and spices, plus lumber, concrete blocks, and many other products. Greenhouses, breweries, snow-melting operations, spas, swimming pools, and laundromats have successfully implemented geothermal heating. Similarly, ground source heat pumps are twice as efficient as furnaces in areas with cold winters. It is astonishing that this source of heat is not used more; once the facilities are built, geothermal heat is totally free.

Near shovel-ready geothermal technology

No significant physical or technological reason prevents geothermal from being installed anywhere to provide all of the electricity we need. One need only dig to a depth hot enough to build a binary plant. The only technological limitation is drilling, but comparatively little investment could easily repurpose the technology we currently use to drill for fossil fuel extraction.

With a small amount of technological advances in drilling technology, geothermal plants could be installed nearly anywhere in the world and could easily meet all of our energy needs with little waste, resources, or footprint. And, an innovation in geothermal is near that would make possible turning geothermal up during the day and down at night when electricity demand is lower, thus eliminating most of the need for utility battery storage. We discuss this new technology in a bonus chapter, but the only remaining technological hurdle before delivery is finding a way to drill in a giant circle – easier said than done, but, again, a problem we can certainly solve.

All this begs the question: if geothermal is such a great option – renewable, low resource use, little waste, little need for battery storage – why have we invested so little in it? The main barrier– both to deploying existing technologies and developing new ones – is an ideological bias against large-scale public projects. Even “small” geothermal projects cost millions of dollars, with large-scale and experimental projects requiring hundreds of millions of dollars in upfront investment. In practice, only governments can reliably undertake such massive projects. By contrast, a single solar panel costs only a few thousand dollars, so the initial investment to get a solar energy startup off the ground is much smaller – on the order of tens of thousands of dollars.

American public policy avoids creating the large, public projects that would be required to install geothermal on a large scale or test out new, instead opting to subsidize private companies that already exist. For example, the Obama administration provided $68 billion in loan guarantees to private solar companies, and the Biden administration awarded $100 billion in grants to private wind and solar companies. The bias in favor of subsidizing private companies – rather than funding government projects – means we have not developed potentially planet-saving geothermal energy technology.

Yet geothermal’s many advantages mean it should be a centerpiece of any green energy transition. This is particularly true because – as we’ll see next – geothermal has a huge advantage in creating the least amount of toxic waste.

Green energy duel 7: And what about waste?

We have finally arrived at the last stage of our green energy duel: waste. In this issue’s introduction, we discussed the waste problem of spent nuclear fuel. But nuclear has a more serious waste problem: mining waste.

In the 1950s and 60s, in the former Soviet Union, probably hundreds of people died from uranium mining waste. However, these were state secrets, so we will almost certainly never know the true death toll. A study in Spain found increases in deaths from cancer for people living near uranium processing but not nuclear powerplants, implicating the mining waste, not waste from electricity generation. Though an equivalent study was not done in the American Southwest,  it is all but certain that uranium mining waste led to substantial increases in cancers and birth defects in the areas where mining occurred. Moreover, studies of uranium miners showed catastrophic incidences of many types of cancers. While US and Soviet uranium mining was intended for atomic weapons, peaceful nuclear energy requires the same type of uranium mining, and some of that mined uranium was ultimately used in nuclear power plants.

The reason uranium mining creates such dangerous waste is that mining is considered viable if the rock consists of just 1% uranium. That means that for every ton of uranium ultimately produced, 99 tons of mining waste – known as tailings – must be disposed of. And in practice, the mining process generates even more tailings because miners must clear out rock in order to reach veins of 1%-or-greater-uranium rock. To reach uranium-rich ore, individual uranium mines in the American Southwest produced 20 to 30 acres of tailings, piled up 30 feet high or greater – that’s in addition to the waste created by processing 1-2% uranium ore.

Why would this waste be dangerous? Isn’t mining waste just ground up rock? If all the rock wasn’t dangerous before mining, why would the mining process suddenly make it dangerous?

In this issue’s introduction, we looked at several examples of heavy metal and radioactive toxins, like lead, arsenic, cadmium, uranium, and americium. In fact, we are surrounded by these deadly toxins in rocks and soil, yet they pose no danger to us. Indeed, cement, concrete, bricks, granite, marble, and other building materials are radioactive (1, 2, 3, 4) yet not dangerous. To understand this paradox, it’s key to recognize that radiotoxic and heavy metal toxins are not dangerous unless they enter your body. When imprisoned inside a rock (or building materials like bricks), these toxins cannot cause any harm. Some highly radioactive atoms can be dangerous even if not ingested, but in practice, when an atom inside a rock undergoes radioactive decay, the rest of the rock absorbs the nuclear radiation before it can leave the rock and cause any harm. In other words, even though we are surrounded at all times by dangerous heavy metals and radiotoxins, they pose zero danger because they are locked inside rock.

The problem is that mining and processing ore breaks up a huge amount of rock, thus liberating heavy metals and radiotoxins. These toxins must be safely contained, lest they poison the soil, water, or air, rendering the entire area unsafe for all living things. As we’ll see below, modern mines produce an unfathomable hundreds of millions of tons or more of waste: an unimaginable amount of toxins, once safely imprisoned inside solid rock, now liberated and extremely dangerous.

Yet deadly, radioactive mining waste is not an issue unique to nuclear energy. People have also been killed by waste from mines that produce minerals needed for a green energy transition. The central problem is the same: massive amounts of mining waste. Most minerals are similar to uranium in that a grade of 1% (1 ton of mineral locked inside 100 tons of ore) is commercially viable. Some minerals are mined at even lower grades: the average copper mine is mining out rock that is only 0.62% copper, producing 160 tons of waste for every ton of copper(!).

As with uranium mining, toxins like cadmium, lead, and arsenic are liberated when so much rock is broken apart. And all forms of mining generate radioactive waste, even if the mineral miners are after isn’t itself radioactive: all rocks have some radioactive atoms within them, and thus anything that breaks apart rock will liberate radioactive atoms. It doesn’t matter what mineral miners are after; the mining process liberates toxins, some of them radioactive, that had been safely locked away inside inert rock.

In 2025, a dam holding back tailings in Zambia collapsed, contaminating the Kafue River. 60% of the 20 million residents of Zambia depend on the Kafue for drinking water, fishing, or agriculture. In the immediate aftermath, the entire water supply of one of Zambia’s largest cities (Kitwe, population: 700,000) had to be shut down for safety. Dead fish washed up on the banks of the river 6 miles away, and overnight, a river rich in riverine animals and birds had died. Crops near the river wilted and died. In August – six months after the spill – the US embassy ordered all US government personnel to leave the region because “hazardous and carcinogenic substances” including arsenic, cyanide, uranium, and other heavy metals had polluted water supplies and – even worse – had possibly become airborne. The Finnish government advised travelers to avoid the area to avoid exposure to toxic heavy metals. Independent investigators estimated that 1.5 million tons of toxic material were released into the river, with “dangerous levels of cyanide, arsenic, copper, zinc, lead, chromium, cadmium, and other pollutants posing significant long-term health risks, including organ damage, birth defects, and cancer.” The mine produced copper, a critical mineral for the green energy transition (remember, a single electric car requires 117 pounds of copper).

In 2015, the tailings dam for the Germano mine collapsed (sources: 1, 2, 3), releasing 43 million cubic meters of tailings – enough tailings to cover three-quarters of Manhattan in a meter of tailings, or toxic muck past your hips. Initially, a tsunami of toxic mud more than 30 feet tall ripped across the landscape, killing 19 people, displacing 400 families, and leaving half-buried ghost towns. Had the mine been in a less remote part of the world, more people would have been affected. Literally hundreds of watercourses – various branches of rivers and streams that meander through the area – suffered “irreversible environmental damage”. In total, the tailings spread over a total of 415 miles of rivers and streams, including 294 different creeks. The extraordinary amount of tailings released left 65.2 miles of three separate rivers so filled with silt that they were no longer rivers. Eleven tons of riverine fish died immediately from mud clogging their gills. However, tons more fish died from the toxic waste and the drop in oxygen caused by the flood of toxic sludge. The forest on the river banks was badly affected. The area is one of the most important areas of biodiversity in the world, and tapir, birds, turtles, amphibians, and countless invertebrates were killed.

Despite the remote location, 41 municipalities were affected, and hundreds of thousands were left without water in the immediate aftermath. A year after the disaster, the water supply or other aspects of life remained disrupted for 3.6 million people. A hydroelectric dam was put out of service. 13 miles of roads were destroyed as well as 12 bridges. Two archaeological sites, six historically significant sites (including buildings dating to the 1700s), and more than 2000 separate cultural or religious sites were destroyed.

The tailings flowed out of the mouth of the Dolce River into the Atlantic Ocean. A year after the disaster, tailings had contaminated beaches along the coast, including one more than 100 miles away. The toxic plume poisoned animals in the Comboios Biological Preserve, including spawning sea turtles.

The Germano mine was mining for iron, the main component of steel. As discussed above, all of our green energy candidates require a great deal of steel, though wind and solar require an order of magnitude more steel than nuclear or geothermal.

Far from isolated incidents, well over 100 tailings dam failures have occurred worldwide. These examples illustrate the danger that mining waste poses to human welfare and the natural world. A full green energy transition will require thousands of new mines, each with hundreds of millions of tons of tailings that need to be safely impounded.

Unlike spent nuclear fuel, tailings do not become less dangerous over time. As discussed in this issue’s introduction, 97% of spent nuclear fuel is no longer radioactive after 300 years; only 3% needs to be sequestered for 10,000 years. At the end of 10,000 years, so many of the radioactive atoms will have undergone their natural decay process that the nuclear waste will be no more radioactive than an ordinary rock (though some atoms decay into toxic heavy metals). By contrast, almost all of the toxins in mining waste do not undergo radioactive decay and thus never become safe: arsenic, lead, cadmium, and chromium, for example, never decay and will be dangerous toxins forever. In other words, billions and billions of tons of tailings will need to be safely stored and monitored, forever.

The issue of mining waste is by far the biggest challenge – technologically and environmentally – of the green energy transition. For this reason, much of this issue focuses on mining waste. But before continuing the discussion of mining waste,If Emperor Anastasius is ancient history to us because he lived 1500 years ago, then the 1500-year gap means that the last king of Athens is ancient history to Anastasius. And because the Great Pyramids were completed 1500 years earlier, the Great Pyramids were ancient history to the last king of Athens. We have to repeat this 1500-year ancient history exercise six times to get to just 9,000 years back. 10,000 years into the future is the point at which the final 3% of nuclear waste will cease to be radiotoxic.
Clearly, 10,000 years is an extraordinary amount of time. 10,000 years ago was before all recorded history: humanity was still 1,000 years away from inventing pottery and 2500 years away from founding cities. It is beyond hubristic to assume that we can build something that can last for 10,000 years – let alone something so perfectly solid and durable that it will never even develop a crack that a single radioactive atom can seep out of. But for heavy metal toxins, 10,000 years isn’t nearly enough time. 100,000 years isn’t enough time. 1 million years isn’t enough time. Heavy metal toxins never become safe.
The green energy deal with the devil
It gets even worse. The minerals we need in massive amounts to phase out fossil fuels – like lithium, cobalt, nickel, copper, and rare earths – are mostly near the earth’s surface. That means that miners must remove all vegetation and overturn all soil in their search for ore. No ecosystem can survive open-pit mining. Literally thousands of ecosystems will need to be destroyed to obtain these minerals.
And so climate change has forced us to accept a deal with the devil. To save the planet from climate change, it is necessary to destroy parts of the planet. Parts of the planet with minerals needed for a green energy transition will have to be sacrificed by way of mining waste and open-pit mining for the rest of the planet to survive. There is no other way, we are told, to replace fossil fuels.
But what if this Faustian bargain is a lie?
As we’ll see in this issue, there are three major ways that this deal with the devil is a lie. First, mining is a massive contributor to greenhouse gas emissions, accounting for an estimated 10% of humanity’s greenhouse gas emissions. These emissions have two sources. First, mining and processing ore require fossil fuels, and most of these activities cannot be decarbonized. Second, the deforestation of open-pit mining generates enormous greenhouse gas emissions. When all the vegetation and microscopic organisms are burned or die off and decay, a tremendous amount of greenhouse gas is released. This is analogous to our discussion of land degradation in Issue 1. As we saw in Issue 1, a quarter of humanity’s greenhouse gas emissions result from land degradation. Once in the atmosphere, the greenhouse gases from desertification or deforestation are no different from greenhouse gases from any other source. Whether released by a fossil fuel power plant or decaying trees, greenhouse gases have the same dangerous, planet-warming effect. Only some fossil fuel use in mining can be eliminated; deforestation cannot be eliminated. In other words, while scientists are unanimous that we must fully eliminate greenhouse gas emissions, we actually cannot do so if we must continually mine to build, repair, and replace green energy infrastructure into the future.
The second way that this Faustian bargain is a lie is that we’re not sacrificing parts of the planet that happen to have deposits of critical minerals; we’re sacrificing parts of the planet that happen to have poor and powerless people who can’t stand up to mining corporations. As we’ll see in Chapter 2, the highest quality nickel ore is found in the US, Canada, and Russia, but the world’s biggest producer of nickel is Indonesia. As a technical matter, it makes no sense to use Indonesian nickel because it requires far more energy to process into a usable form. But, as a political matter, it makes perfect sense: no one wants a mine opened near their home, so mines are more likely to be opened where people lack the power to fight back. Similarly, rare earths are relatively uniformly distributed around the earth’s surface, but mining is concentrated in Myanmar, where impoverished locals and a weak, corrupt government are unable – or unwilling – to prevent illegal mining.
The third reason this Faustian bargain is a lie is that we don’t need all the energy we think we do. Our economies are so grossly inefficient that we could reduce our energy use while improving our quality of life. As we’ll see in Chapters 3 and 4, there is no better example than electric cars.
By the end of Chapter 4, a way forward will be clear: how we can phase out fossil fuels while minimizing mining and improving our quality of life. we need to wrap up our green energy duel. We’ll first judge the winner in the waste category, then determine the winner overall.

Which form of green energy generates the least waste?

To answer the question posed by this section, geothermal generates the least amount of waste, followed by nuclear, with solar and wind in a distant third and fourth. Primarily, wind and solar generate the most waste because of the sheer number of panels and turbines required. As discussed above, a single nuclear power plant can generate the electricity of 8.5 million solar panels or 800 wind turbines. Additionally, enormous resources are required to build transmission lines to collect all the electricity from hundreds of turbines or millions of panels, a problem neither nuclear nor geothermal face. Between wind and solar, wind power generates substantially more waste because wind turbines require rare earths, and rare earth mining generates an astonishing amount of radioactive waste. We consider this thorny issue in greater detail in Chapter 2.

For nuclear energy, the radioactive waste from spent nuclear fuel gets a disproportionate amount of attention. But clearly, uranium mining waste is an orders of magnitude larger problem. As discussed in this issue’s introduction, all 92 nuclear power plants (54 active plus 38 decommissioned) that have ever been operated since the 1950s combined have generated a total of 90,000 metric tons of spent nuclear fuel waste. Remember, a single modern mine produces hundreds of millions of tons of tailings. In other words, the entirety of nuclear waste ever produced by every single nuclear power plant in the US is well under one-tenth of one percent of the radioactive toxic waste produced by a single modern mine. And, as discussed in the Introduction, 97% of spent nuclear fuel is no longer radiotoxic within 300 years, and much of it decays into harmless substances like zirconium – while mining waste never becomes less dangerous.

Were waste generated by the plants the only waste issue, geothermal would be the clear winner. Older geothermal plants generate only steam as waste, but newer plants generate no waste at all: the fluid used to push the turbines circulates in an endless loop, returning deep underground to heat up after being used to generate electricity.

But as with the section on resource use, this exploration of the waste of green energy reveals how limited our green energy duel really is. The vast majority of mining waste from a green energy transition won’t be a byproduct of the obtaining materials needed to build electricity generation capacity, but rather a byproduct of obtaining the materials needed to make utility-scale batteries and “green” replacements to things that run on fossil fuels, like electric cars. Indeed – as we will investigate in Chapter 3 – the bulk of the demand for minerals – and thus the biggest driver of mining waste in a green energy transition – is electric cars. In sum, the amount of mining waste generated by the green energy transition depends less on how we generate the electricity and more on the fact that we need to charge up electric cars. While geothermal and nuclear may generate less waste than wind and solar, any green energy transition that replaces all of our gasoline-powered cars with electric cars will generate a tremendous amount of mining waste.

Putting all this together, no matter how we choose to generate green energy, a green energy transition will require opening thousands of new mines, each of them generating hundreds of millions of tons of toxic tailings waste – waste that will be toxic forever.

Green energy duel conclusion: losing sight of the forest (because it was destroyed by mining)

In order to plan out a just transition away from fossil fuels, it is necessary to see the big picture – not to lose sight of the forest because we’ve focused on a particular set of trees. We have so far seen this in two different ways.

First, it felt logical to end the green energy duel when we realized that nuclear energy is not renewable. However, ending the comparison there would have overlooked the material inputs and environmental harm of a green energy transition. Specifically, solar and wind energy may be renewable, but both have significant drawbacks (massively larger resource requirements, footprint, and mining waste). These drawbacks don’t eliminate wind and solar from contention, but as we saw from examples like the Ivanpah solar farm and the collapse of the Germano tailings impoundment, we must have a plan to manage those problems. Second, when we focused on an overall winner – which type of energy is the most environmentally friendly – we lost sight of the fact that most of the material inputs and waste of a green energy transition are not actually destined for generating electricity. The biggest need for minerals (and thus the biggest contributor to mining waste) is electric cars, due to the large amount of minerals needed to manufacture electric cars themselves, plus all the material inputs needed to generate the extraordinary amount of electricity to keep them charged up and running.

But there is a third way we can easily miss the big picture. When we dive in headfirst and start planning out our green energy transition, we fail to ask more fundamental questions about how our world should work. For example, we never considered the possibility that perhaps we don’t need all the energy we think we do. Maybe there is a different way to run the world. Maybe we can maintain our high quality of life and use less energy. We consider this possibility in Chapters 3 and 4. But first, we need to fully understand the problem of mining waste.

Dam you straight to heck

This issue makes the case that it is both necessary and possible to reduce our resource and energy use. In Chapters 3 and 4, we look at concrete ways that we can do so while improving our quality of life. However, before making that case, we have to more thoroughly establish why it is necessary to reduce our energy and resource use. That can’t be done without fully illustrating why better technology, regulation, and monitoring are inadequate solutions to the problem of mining waste. In other words, we will demonstrate in this section that the only viable solution to mining waste is to do less mining. This is a problem we cannot afford to ignore: according to the most recent (2000) estimates, there are 3,500 tailings dams in the world, and a full green energy transition will require thousands more.

Above, we saw examples of catastrophes resulting from tailings impoundment failures: people killed, homes wiped out, and irreparable ecological damage. But what actually is a tailings impoundment? How are tailings stored away?

Tailings impoundments are massive earthen rings that encircle mining waste. Modern tailings impoundments are among the largest human-made structures on earth. The largest tailings impoundments are more than a mile thick and more than 40 feet tall, snaking through the landscape in a giant circle more than 10 miles around. Such massive structures require more than half a cubic kilometer of construction material, or enough to cover an area the size of Chicago with more than a meter of construction material. As miners clear away valueless rock to access mineral-rich rock, they dump it into the earthen ring. Waste from processing ore – corrosive chemicals that can dissolve rock – is also added. As more and more waste piles up, the impoundment is built higher and higher accordingly. Once the mine is exhausted, the top of the tailings impoundment is covered with earth. In this way, toxic tailings are encased in earth and isolated from the outside world. This description may make tailings impoundments sound simple, but in reality, they are complex technological wonders. From accurate subsurface analysis to choosing the construction material most appropriate for conditions, from engineering design to the actual construction, an extraordinary amount of planning, knowledge, and work goes into tailings impoundments. Tailings dams generally cost tens to hundreds of millions of dollars to build, and modern mines produce hundreds of millions of metric tons of tailings waste.

There are better and worse designs for tailings dams, but we need to be realistic about what can actually be accomplished when faced with such a difficult technological problem. Tailings impoundments must keep corrosive chemicals and individual toxins locked away, forever. How can we possibly design a structure that corrosive chemicals will never seep out of? How can we design something so perfectly solid that toxins like lead and uranium  – at the level of an atom – can never find a hole tiny enough to slip out of?

A common belief is that better technology and better regulation can clean up any type of pollution. This cannot be squared with real-world experience. If better technology led to improved tailings dams, then brand new tailings dams with the latest technology wouldn’t collapse; they have. Similarly, better monitoring should be able to identify problems and prevent failures. In reality, tailings dams have failed while they were still being filled, when mining personnel were everywhere. It’s also not true that the free market can fix this problem: prices of minerals are expected to rise due to the demand of the green energy transition, and higher mineral prices should mean more money available to build better tailings impoundments. Yet the decade 2000-2010 saw both the highest mineral prices in a century and a substantial increase in high-severity tailings dam failures. Higher mineral prices, in other words, do not lead to safer tailings impoundment. Finally, it’s also not true that better regulation can fix the problem: tailings dams have failed in countries like Canada, Spain, Finland, and Sweden – hardly countries with unusually lax environmental regulation or enforcement. We can’t innovate or regulate our way out of mining waste.

This is especially true because tailings dams cannot be significantly improved after they are filled. There is no option of doing the best we can today and coming back with more resources and better technology years later: just as a swimming pool must be drained to make repairs, construction crews cannot SCUBA dive into toxic tailings and reinforce miles and miles of a dam that is forty feet tall.

This point is driven home with the so-called upstream tailings dam construction (see the graphic below). It is by far the cheapest design but obviously less safe: In an upstream construction, the tailings themselves are used to structurally support the dam, even though tailings are not construction material and are not optimized for structural stability (and some tailings are liquid(!)).

Yet downstream construction – while safer – is not safe. Though a rough calculation (because it includes tailings dams of different ages), an estimated 5% of upstream tailings dams have failed, and 2-3% of centerline and downstream tailings dams have failed.

These numbers are not reassuring. If 2% of all tailings dams fail every 40 years, all will have failed within 2000 years, leading to thousands of catastrophes like Germano. Considering the massive size of tailings impoundments – hundreds of millions of tons of toxic tailings, 10 miles around, forty feet high – and the mind-boggling timescales, it becomes clear why there is no amount of innovation that can solve this problem.

Weather forecast for the next 200,000 years

Tailings dams don’t suddenly fail; there is usually a precipitating event – something that overwhelms the dam. Though the data are incomplete, the most frequent precipitating event is extreme weather, and the second most frequent is an earthquake (see the Center for Science and Public Participation’s (CSP2) database of failures and this scholarly study of causes). If so much rain falls that it overwhelms the impoundment’s drainage system, the weight of the water can overwhelm the strength of the dam, especially if the water has seeped into the earthen dam and softened it. And, an earthquake simply collapses a portion of the dam in the way earthquakes destroy any human-made structure, as has occurred repeatedly in copper mine tailings dams in Chile.

Thus, to design a safe tailings dam, we must ensure that – forever – there will never be an earthquake large enough, or extreme weather event forceful enough, to breach the dam. This is fantasy. For earthquakes,

Seismologists know that there are many active faults that have not been mapped or have been mapped inaccurately, that some faults believed to be inactive may actually be active, and that there are many inactive faults that may become active again.

With the very real possibility that a tailings mine is built directly on top of an undiscovered fault line – a virtual certainty given that thousands of tailings dams already exist and thousands more needed for a full green energy transition, plus the geologic timescale tailings dams must remain intact – CSP2 recommends that the only safe option is to design all tailings dams to withstand an earthquake “that ruptures the ground surface on which the dam is built.”

Moreover, the authors of the report point out that the earthquake that caused the Fukushima power plant disaster in Japan was eight times more powerful than seismologists had estimated to be the most powerful earthquake that fault could ever produce. We simply don’t understand seismology well enough to make the necessary estimates to ensure each tailings dam can withstand an earthquake; we certainly don’t understand seismology well enough to accurately predict earthquakes for hundreds of thousands of years and beyond.

Likewise, the idea that we can confidently predict the strongest weather event a tailings dam will ever experience, hundreds of thousands of years into the future and beyond, is similarly fanciful. 10,000 years ago was the most recent Ice Age. We can’t possibly predict what the climate will be like in a specific area in a few thousand years; we obviously can’t predict individual weather events. How can engineers design for problems we can’t foresee?

The issue of changing climates and extreme weather is made more acute by climate change. The climate is already changing in unpredictable ways, and extreme weather events have already become more probable. In other words, the technological and engineering challenge of tailings impoundment is getting even harder to solve.

Would you like your poison solid or liquid?

CSP2 recommends (more detail here and here (p10)) that all tailings be solid. That’s because when a tailings dam fails, liquid tailings spill out over an enormous area, causing catastrophic, unremediable damage like at Germano. By contrast, solid tailings will mostly stay in place. In fact, CSP2 recommends that the tailings be structurally stable without the dam; in other words, the dam should simply be there to prevent the tailings from coming into contact with the outside world and protect it from wind and water erosion, but the dam isn’t actually necessary to hold the tailings in place. If this can be achieved, the advantage is obvious: failure of a solid tailings dam causes no harm as long as the breach is quickly repaired.

Unfortunately – aside from being dramatically more expensive – there is a serious drawback of solid tailings, called acid mine drainage. Liquid tailings can be treated so that toxic heavy metals cannot escape: the technical term is “chemical stability.” We normally think of metals as a solid, but metals actually dissolve in water that is acidic. This is a problem because when heavy metals are dissolved in water, they can leach out of a tailings impoundment and into groundwater.

However, if a basic reagent is added, it lowers the acidity (raises the pH) of the tailings and the heavy metals “precipitate” – turn solid. In a basic environment (a pH of about 9), the metals will remain solid and will therefore be unable to leach out of the tailings dam. However, this process is only possible in liquified tailings; there’s simply no way to get a basic reagent mixed into solid tailings. This is the drawback of solid tailings: since the tailings cannot be made basic, toxic heavy metals are certain to slowly leach out of the dam and make their way into groundwater. In other words, the groundwater around a tailings dam with solid tailings will always be poisoned, and anyone who ever drinks from this groundwater will have to treat it to remove the heavy metals, forever.

The unappealing choice is thus between a catastrophic failure and a slow failure. Liquid tailings don’t leach heavy metals, but they do risk catastrophic failure, sending toxic waste over enormous expanses of land all at once. Solid tailings do not fail catastrophically, but they are certain to continuously, albeit slowly, release toxins into the groundwater. As we saw above, we must expect that all tailings dams will eventually fail. For this reason, CSP2 argues that the lesser of two evils is solid tailings – particularly since a single modern mine produces hundreds of millions of tons of mining waste, or so much tailings that the environmental damage of a liquid tailings dam failure is literally unremediable.

Nonetheless, we need to take seriously the fact that solid tailings will impose serious harm on future generations. Tailings dams need to be monitored for problems in order to prevent failure. If a solid tailings impoundment is breached, it must be quickly repaired, or wind and water erosion will spread toxic tailings far and wide. But how do we know that people 1000 years in the future will still know where all the solid tailings impoundments are and have the capacity to monitor, maintain, and repair them? If you think this is a trivial problem, think back to the ancient history thought exercise in this issue’s introduction.

Similarly, will people 1000 years from now know the groundwater around all these thousands of tailings dams is not safe to drink and how to treat it? In 2000 years? 50,000 years? 100,000 years? As discussed in the introduction, 7500 years ago, the very first cities were being settled, and 9000 years ago, pottery was being invented. We cannot possibly know that humanity will remember where all of these thousands of tailings impoundments are located, let alone have the ability to monitor, maintain, and repair them.

Another major issue is that groundwater doesn’t always stay as groundwater. Groundwater is water that has seeped into the soil, up to hundreds of feet deep and across endless miles of Earth’s surface. Toxins dissolved in groundwater thus cannot be removed with any technology because doing so would require somehow pulling all the water out of the ground over countless square miles, hundreds of feet deep into the earth. Fortunately, unless accessed by humans as drinking water, toxic groundwater is not dangerous. But groundwater can become surface water (like a river or lake) if it is forced upwards. The source of all rivers is either melting snow or groundwater that has been forced to the surface. CSP2 cautions that a mine should never be approved if the groundwater in the area becomes surface water.

But the timescales involved are enormous. Climatic or geological changes could alter the behavior of groundwater. Groundwater confined underground today may eventually be forced up to the surface by changes to climate or geology that we cannot predict. We can’t possibly be certain that leachate from a solid tailings impoundment will stay deep underground as groundwater, forever.

The reason we are facing a climate crisis is that people in positions of power thought that people living many years in the future – us – don’t matter. If we accept the perpetual poisoning of landscapes via acid mine drainage, we’re engaging in the very same thinking that got us into this mess in the first place. Whether liquid or solid, tailings are a clear danger to future generations, and we should not address the climate crisis with the same disregard for future generations that caused the climate crisis in the first place. Moreover, we certainly cannot claim to be “saving the planet” from climate change if we’re poisoning the very earth we are claiming to protect.

In situ mining

Clearly, there is no solution to mining waste: there is no technological solution that can confidently contain tailings for the necessary timescales, no regulatory solution that can ensure prudent monitoring and maintenance. But what if there were a different way to mine that did not generate so much waste?

In situ leach mining eliminates much – but not all – mining waste. In this section, we investigate uranium mining to establish the principles of in situ mining.

In the 1960s, in situ leach mining of uranium was attempted in the US and the Soviet Union; today, most uranium mining worldwide occurs via in situ methods, including in the US. In situ leach mining does not resemble traditional mining at all: there is no excavation whatsoever. Rather, small holes are drilled deep into the ground and chemicals are pumped in; these chemicals dissolve the uranium, and miners collect the uranium-rich solution through a different borehole, sucking the solution up like a straw. The solution is then taken off-site to extract the uranium from the solution and turn it into a usable form.

The least environmentally harmful process uses carbonate ions, the same component that makes the bubbles in sodas. When carbonate ions encounter uranium, a series of chemical reactions occur that eventually create U₃O₈, which is soluble in water.*

In situ mining is not possible for all uranium deposits. The rock must be porous enough to pump the chemical solution through it. In situ is also impossible if the uranium is surrounded by compounds that react with carbonate ions. Thus, much uranium ore can only be accessed via traditional mining.

Because there is no excavation, in situ leach mining generates substantially less waste overall and is substantially less harmful than traditional mining. In situ also eliminates the occupational hazards of mining, from breathing in toxic dust or gases, to the use of explosives and the danger of tunnel collapses. Nonetheless, in situ is not without significant harm. First, the chemicals used are not specific to uranium; they dissolve any heavy metal. In other words, the liquid drawn up contains not merely uranium, but a host of other toxic heavy metals, some of them also radioactive. Thus, once the uranium is processed, it leaves behind a toxic, radioactive soup of heavy metals. In other words, though in situ doesn’t generate tailings, it does generate a more concentrated waste that needs to be dealt with.

Second, the source of carbonate is often ammonium carbonate, which generates the pollutant NO₃ in large quantities. Ammonium carbonate consists of two molecules of ammonium for every one molecule of carbonate. Thus, every carbonate generates two molecules of NO₃. This huge amount of NO₃ is not easily disposed of.

Finally, it is not possible to remove all the chemical solution forced into the rock. All unrecovered chemical-bearing solution will eventually become incorporated into groundwater, along with whatever it has dissolved. This – obviously – poisons the groundwater with heavy metals – some of them radioactive – and other toxins (such as NO₃), rendering a once-clean source of water undrinkable.

Groundwater contamination remains a serious problem for in situ leach mining, despite decades of research into remediation. Ruiz et al state that “When feasible, [in situ leach mining] greatly reduces waste generated by the mining and milling processes, however, the ability to restore ground water to acceptable quality after [mining] ends is uncertain.”** The Black Hills Clean Water Alliance states more succinctly (though no less correctly), “Water at an in situ leach uranium mine has never been returned to its original condition.”

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In sum, in the limited cases where in situ methods can be used, it is substantially less harmful than conventional mining as it does not require excavation, thus generating substantially less waste. The major problem with in situ is that it is impossible to recover all the solution injected into the ground, so it contaminates groundwater permanently. Of course, traditional mining also poisons groundwater; the point is that there is no environmentally friendly form of mining. There are more and less harmful ways of mining, but there is no such thing as harmless mining.

Conclusion: the type of thinking that got us into trouble can’t be the thinking that gets us out

Chapter 1 started out as a duel between nuclear, wind, solar, and geothermal energy to see which was the best option to phase out fossil fuels. This exercise led to some surprising conclusions. Geothermal was surprisingly competitive. The large difference in resources required was impressive, with a single nuclear power plant able to produce as much electricity as 800 wind turbines or 8.5 million solar panels.

But the further we got, the clearer it became that debating the merits of different forms of green energy was missing more fundamental questions. When we rushed headlong into planning out our green energy transition, we failed to ask more fundamental questions about how our world should work. For example, we never considered the possibility that perhaps we don’t need all the energy we think we do. Indeed, fossil fuel corporations are corporations: as discussed in Iss1/Ch4, they are legally bound to pursue profits above all other considerations. More energy use means more profits, and given the massive political, economic, and social clout held by fossil fuel corporations, it would be shocking if we were not using more energy than we need. This matters greatly because, as we saw here in Chapter 1, mining waste imposes severe environmental impact. If we can reduce our energy needs, we can prevent literally billions of tons of mining waste from being created. In Chapters 3 and 4, we study one dramatic example of how we can massively reduce our energy use while improving our quality of life. But first, Chapter 2 examines the mining processes for some of the critical minerals of the green energy transition.

*An alternative chemical process has never been approved in the US due to even greater difficulty with groundwater remediation compared to the carbonate method.

*The most promising attempts at groundwater remediation involve using bacteria that naturally live in extreme environments with lots of toxic heavy metals. These bacteria have evolved ways of turning dissolved heavy metals into solid heavy metals; once solid, they are no longer harmful. In principle, if these bacteria are introduced into an aquifer that has been contaminated by in situ mining, they should be able to remediate the water. Wufuer et al point out that:

Among the uranium bioremediation techniques available, uranium bioreduction has been studied extensively, where U(VI) is reduced to U(IV) by a variety of bacteria. In situ demonstrations of uranium bioreduction have been conducted successfully at the US DOE Rifle site, Colorado [27], and at the US DOE Oak Ridge site, Tennessee [28,29]. However, the stability of reduced U(IV) depends on protecting it from re-oxidation by nitrate [30,31] and O₂ [28].

Ruiz et al summarize non-bioremediation attempts (which have not proven successful) and overall agree that bioremediation may not be permanent:

Newsome et al. (2014), in an extensive review, summarized the results of field studies in which in-situ bioremediation of U was investigated at the Rifle, CO mill tailings site, and ground water contamination at sites in Oak Ridge, TN and Hanford, WA. The studies have found that while in-place immobilization of U can be achieved through microbial reduction, this effect may be temporary with subsequent release of U and other constituents after organic feed is discontinued or after re-oxidation.