extraction

Hidden hydrogen

July 15, 2025 By EarthWise Leave a Comment

The idea of using hydrogen as a fuel or an energy source has been around for a long time. Hydrogen is the most common element in the universe, but most of it is locked up in various chemical compounds, such as water. Hydrogen is a clean fuel; burning it or using it to generate electricity in a fuel cell produces no greenhouse gas emissions. But more than 99% of the hydrogen that people current produce is obtained by methods that result in greenhouse gas emissions.

A new study by scientists at the University of Oxford, the University of Durham in the UK, and the University of Toronto looks at geological environments in which naturally occurring hydrogen could be hiding. According to the study, over the last billion years, the Earth’s continental crust is likely to have produced enough hydrogen to satisfy the energy needs of modern society for 170,000 years.

Much of that hydrogen is likely to have been lost or is inaccessible; most of it is not economically feasible to extract. But even the relatively small amount of hydrogen left could provide thousands of years of energy for us. We just have to be able to find it.

The researchers have developed what they call an “exploration recipe” which identifies where natural hydrogen might be located as well as where it could be commercially feasible to extract. These places with hydrogen have so-called reservoir rocks and geologic formations that prevent the gas from leaking into the atmosphere.

A few such places have already been identified such as one in Albania. There are various candidates to explore, even including an area in Kansas. The study’s authors have founded a company whose mission is to find these natural sources of hydrogen.

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Scientists Say Hidden Hydrogen Could Power the World for 170,000 Years

Photo, posted October 4, 2019, courtesy of Tony Sprezzatura via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Our cities are sinking

June 24, 2025 By EarthWise Leave a Comment

A new study by the Columbia University Climate School has found that all of the 28 most populous cities in the United States are sinking to some extent. This phenomenon of subsidence is not just taking place in cities on the coast, where relative sea level is an issue, but also in cities in the interior.

The primary cause of subsidence is large-scale groundwater extraction for human use. When water is withdrawn from aquifers made up of fine-grained sediments, the pore spaces formerly occupied by water can eventually collapse, leading to compaction below and sinkage at the surface.

The fastest sinking city in the US is Houston, with more than 40% of its area subsiding more than 5 millimeters a year and 12% sinking at twice that rate. Some local spots are going down as much as 5 centimeters a year. These seem like very small numbers but the fact that the subsidence is often not uniform across an urban area means that there are stresses to building foundations and other infrastructure. Parts of Las Vegas, Washington D.C., and San Francisco have particularly fast sinking zones.

There are other causes of subsidence. In Texas, pumping of oil and gas adds to the phenomenon. A 2023 study found that New York City’s more than one million buildings are pressing down on the Earth so hard that they may be contributing to the city’s ongoing subsidence. About 1% of the total area of the country’s 28 largest cities faces some danger from uneven subsidence.

Overall, some 34 million Americans live in cities affected by subsidence. Global cities facing especially rapid subsidence include Jakarta, Venice, and here in the U.S., New Orleans.

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All of the Biggest U.S. Cities Are Sinking

Photo, posted December 27, 2012, courtesy of Katie Haugland Bowen via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sand mining and the environment

March 18, 2025 By EarthWise Leave a Comment

Sand mining is the world’s largest mining endeavor. It is responsible for 85% of all mineral extraction. It is also the least regulated, possibly the most corrupt, and likely the most environmentally destructive. Sand is the second-most exploited natural resource in the world after water. Its global use has tripled in the past two decades. More than 50 billion tons of sand is extracted from the environment each year.

Sand plays a critical role in much of human development around the world. It is a key ingredient of concrete, asphalt, glass, and electronics. It is relatively cheap and relatively easy to extract. But we use enormous amounts of it.

Sand mining is a major threat to rivers and marine ecosystems. It is linked to coastal erosion, habitat destruction, the spread of invasive species, and damage to fisheries.

The harm from sand mining is only beginning to attract widespread attention. A recent study by an international group of scientists published in the journal One Earth identifies threats posed by sand mining. Sand extraction in marine environments remains largely overlooked, despite sand and sediment dredging being the second most widespread human activity in coastal areas after fishing.

Sand is generally seen as an inert, abundant material, but it is an essential resource that shapes coastal and marine ecosystems, protects shorelines, and sustains both ecosystems and coastal communities. Sand extraction near populated coastlines is particularly problematic as climate change makes coastlines increasingly fragile.

Like all other resources on our planet, even sand cannot be taken for granted. It must be responsibly managed.

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The rising tide of sand mining: a growing threat to marine life

Photo, posted February 7, 2013, courtesy of Pamela Spaugy / U.S. Army Corps of Engineers via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Natural hydrogen

February 26, 2024 By EarthWise Leave a Comment

Hydrogen is considered to be a potential substitute for conventional fossil fuels in applications where electricity cannot easily be used such as in blast furnaces, cement works, industrial heating, long-distance aviation, and shipping. But most hydrogen is manufactured by separating it from methane, which is energy-intensive and produces carbon dioxide. So-called green hydrogen is made by splitting water using electricity. It is a carbon-free process if the electricity is from renewable sources, but it is pretty expensive.

A small community in Mali gets its electricity by burning natural hydrogen, which bubbles up from underground into a village well. It has long been known that processes in the Earth’s crust can make hydrogen gas from water under certain circumstances. But conventional wisdom has been that this occurrence is rare and that the hydrogen produced is either inaccessible or seeps away.

An increasing number of geoscientists now are convinced that there is actually an enormous quantity of hydrogen beneath the planet’s surface and that we just haven’t been looking for it in the right places, or at all, for that matter. Some say that there could be trillions of tons of hydrogen, and more is being generated all the time.

Prospectors have recently been drilling for hydrogen in France, Australia, Morocco, Brazil, and in the United States, in Nebraska, Arizona, and Kansas. Will extracting natural hydrogen be practical at the scale required and will it be economical? The jury is still out on all of this, but if it turns out as proponents claim, natural hydrogen could be a very big deal.

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Natural Hydrogen: A Potential Clean Energy Source Beneath Our Feet

Photo, posted November 4, 2012, courtesy of Heather Paul via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Mining Metals From Water | Earth Wise

March 14, 2023 By EarthWise Leave a Comment

Researchers at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Washington are working with industry to develop a method of extracting valuable materials from various sources of water. The technique is the 21st-century equivalent of panning for gold in rivers and streams.

The patent-pending technology makes use of magnetic nanoparticles that are surrounded by an absorbent shell that latches on to specific materials of interest that are found in certain water sources. These sources could include water in geothermal power plants (known as geothermal brines), water pulled from the subsurface during oil or gas production, or possibly effluents from desalination plants. Extracting valuable materials from geothermal brines could greatly enhance the economics of geothermal power plants.

The initial focus of the development is on lithium, which is an essential element in many high-technology applications, especially in the batteries that power cell phones, computers, and electric cars. The global market for lithium is projected to reach over $8 billion a year by 2028 and very little of it is currently produced in the United States.

The tiny particles are added to the water and any lithium is drawn out of the water and is bound to them. Using magnets, the nanoparticles can be readily collected. Once the particles are no longer suspended in liquid, the lithium can easily be extracted, and the nanoparticles can be reused.

PNNL is developing the technology in partnership with a company called Moselle Technology as well as with other commercial partners. This new technology offers the promise of extracting critical materials in a quick, cost-effective manner.

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Tri-Cities Scientists “Magically” Mining Metals From Water

Photo, posted June 4, 2012, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Clean Energy Transition Is Accelerating | Earth Wise

December 2, 2022 By EarthWise Leave a Comment

The world’s economies including its energy markets have been in turmoil in recent times but despite the chaotic conditions, the shift to clean energy is gaining momentum. This year, for the first time, the world is investing more in wind and solar power than in oil and gas drilling. Investments in renewables are expected to reach $494 billion this year, more than the $446 billion directed towards oil and gas extraction. It is rather sobering to realize that the world is still spending nearly half a trillion dollars a year to dig up more oil and gas.

According to the International Energy Agency, there will be an estimated 340 gigawatts of new renewable power capacity installed in 2022. This is roughly equal to the total installed power capacity of Japan, which has the world’s third-largest economy. This year is also seeing tremendous growth in electric cars, which are projected to make up 13% of all light-duty vehicle sales across the globe.

According to analysis by Bloomberg Green, 87 countries are now getting at least 5% of their power from wind and solar. This number is considered to be a critical tipping point at which emerging technologies become more widely adopted. The United States reached that 5% threshold in 2011. Last year, our country surpassed 20% solar and wind power. If we follow trends set by pioneering countries like Denmark, Ireland, and others, wind and solar will supply at least half of our power within the next decade.

Despite the turbulence in global energy markets, the shift to clean power is ongoing. Estimates are that global spending on renewables will double over the next 10 years.

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Despite Turmoil in Energy Markets, the Shift to Clean Energy Is Gaining Steam

Photo, posted June 12, 2013, courtesy of Activ Solar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sinking Cities | Earth Wise

October 24, 2022 By EarthWise Leave a Comment

Sea levels across the globe are rising as a result of the changing climate. Two factors are largely responsible: the melting of ice sheets in the polar regions and the fact that as the oceans get warmer, the water in them expands.

Estimates are that by 2050, there will be over 800 million people living in 570 cities that will be at risk from rising sea levels. The rising waters can drown neighborhoods, put people’s lives at risk, and wreck entire economies. Unless global emissions can be reduced sufficiently, sea levels will continue to rise.

A new study, published in the journal Nature Sustainability by Nanyang Technical University in Singapore in collaboration with the University of New Mexico, ETH Zurich, and NASA’s Jet Propulsion Lab, has focused on yet another aspect of the threat to coastal cities. They have found that many densely populated coastal cities worldwide are even more vulnerable to sea level rise because much of their land is sinking.

The researchers processed satellite images of 48 cities from 2014 to 2020 using a system called Interferometric Synthetic Aperture Radar. They found that land subsidence varied on a neighborhood and even individual block level but across all the cities studied, there was a median sinking speed of 6/10” a year. Some places had land that is sinking at 1.7” per year. Meanwhile, the global mean sea-level rise is about .15” per year.

The increasing prevalence of industrial processes such as the extraction of groundwater, and oil and gas, along with the rapid construction of buildings and other urban infrastructure are leading to the sinking of the urban areas.

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Rapid land sinking leaves global cities vulnerable to rising seas

Photo, posted October 24, 2015, courtesy of Jeffrey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lithium-Sulfur Batteries | Earth Wise

July 19, 2022 By EarthWise Leave a Comment

Existuje také spousta přípravků ve formě vitaminových a minerálních komplexů, které nasycují tělo všemi užitečnými zdroji pro správné fungování celého těla a sexuálního systému. Nejoblíbenější jsou dnes syntetické stimulanty, protože poskytují silný apothekeein.com a stabilní účinek, doplňky stravy a homeopatické léky se častěji používají pro prevenci problémů tohoto druhu.

The growing use of electric vehicles as well as energy storage systems has created a major focus on the batteries for these applications. Lithium-ion batteries dominate these applications and the demand for the materials needed to manufacture them continues to grow.

The raw materials for these batteries include not only lithium, but also can include nickel, manganese, and cobalt.

Sulfur has been a desirable alternative for use in lithium-based batteries for quite a while because it is an abundant element and can be extracted in ways that are safe and environmentally friendly. However, previous attempts to create lithium batteries that combine sulfur cathodes and the standard carbonate electrolytes used in lithium-ion batteries have not been successful because of irreversible chemical reactions between intermediate sulfur products and the electrolytes.

A group of chemical engineers at Drexel University has now found a way to introduce sulfur into lithium-ion batteries that solves the stability problem and also has major performance advantages. The new batteries have three times the capacity of conventional lithium-ion batteries, and last more than 4,000 recharges, which is also a substantial improvement.

The new battery technology involves creating a stable form of sulfur called monoclinic gamma sulfur by depositing the sulfur on carbon nanofibers. Previously, this sulfur phase was only observed at high temperatures and was only stable for 20 or 30 minutes. This chemical phase of sulfur does not react with carbonate electrolytes and therefore produces a battery that is chemically stable over time.

Incorporating this sulfur into battery cathodes results in a better battery that doesn’t need any cobalt, nickel, or manganese. It could be the next big thing in electric vehicle batteries.

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Breakthrough in Cathode Chemistry Clears Path for Lithium-Sulfur Batteries’ Commercial Viability

Photo, posted April 5, 2022, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sand From Mining Waste | Earth Wise

May 10, 2022 By EarthWise Leave a Comment

The natural resources people use the most are air and water. It may come as a surprise that in third place is sand. Sand is used to make glass, computer chips, toothpaste, cosmetics, food, wine, paper, paint, plastics, and more. It is estimated that 50 billion tons of sand are used each year.

Concrete is 10% cement, 15% water, and 75% sand. The concrete required to build a house takes on average 200 tons of sand, a hospital uses 3,000 tons, and a mile of a highway requires 15,000 tons.

One would think that there is no shortage of sand, but we are using it up faster than the planet can make it and the extraction of sand from seas, rivers, beaches, and quarries has negative impacts on the environment and surrounding communities. For example, removing sand leads to erosion in riverbanks, significantly increasing the risk of flooding in some places.

A potential strategy to reduce the impact of extracting sand to meet society’s growing need for is also a strategy for helping to reduce the production of mineral mining waste, which is the largest waste stream on the planet. Mining produces between 33 and 66 billion tons of waste material each year.

A new study by researchers in Switzerland and Australia looked at the potential for using mining waste as a source of so-called ore-sand. Sand-like material left over from mining operations could be used for many current applications for sand. Separating and repurposing these materials before they are added to the waste stream would not only reduce the volume of waste being generated by mining operations but would also create a responsible new source of sand.

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Solution to world’s largest waste stream: Make sand

Photo, posted October 22, 2005, courtesy of Alan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Oil Drilling In Los Angeles | Earth Wise

February 24, 2022 By EarthWise Leave a Comment

Movies were not the first industry to boom in Los Angeles. Oil was. There was a lot of it, and it flowed close to the surface triggering rampant drilling all over the area. By the 1920s, Los Angeles was one of the largest oil-exporting regions in the world.

A century later, there are over 20,000 active, idle, or abandoned wells spread across LA county, home to 10 million people. Some are hidden behind facades; others are plainly visible, pumping away day and night. About a third of Angelenos live less than a mile from an active well site. In the last 20 years, improved oil extraction technology has actually led to a resurgence of oil drilling in Los Angeles.

Studies of the health impact of LA’s oil wells found that asthma is significantly more common among people living near oil wells than elsewhere in the county. Surveys of residents’ lung functions revealed lower function on average when people live near wells. Measurements of toxins in the air – such as benzene, toluene, and n-hexane – showed that levels of these substances were significantly reduced when oil production at a site stopped.

This issue has finally come to the forefront after a nearly a decade of community organizing and studies of adverse health effects. In a unanimous vote on January 26, the Los Angeles City Council took the first step toward phasing out all oil and gas extraction in the city by declaring oil extraction a nonconforming land use. The LA County Board of Supervisors voted unanimously to phase out oil extraction in unincorporated county areas. Los Angeles’ long, troubled history with urban oil drilling appears to be nearing an end.

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Los Angeles’ long, troubled history with urban oil drilling is nearing an end after years of health concerns

Photo, posted March 26, 2016, courtesy of Giuseppe Milo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Ways To Make Bioplastics | Earth Wise

August 27, 2021 By EarthWise Leave a Comment

The world produces over 300 million tons of plastics each year, mostly produced from petroleum. The environmental consequences are substantial and there is a critical need to replace as much of that plastic production with biodegradable plastics as possible. Thus, there is global research aimed at making bioplastics more economical and as environmentally friendly as possible.

Researchers at Texas A&M University have developed an improved approach for making bioplastics from corn stubble, grasses, and mesquite agricultural production. Apart from the obvious environmental benefits of having biodegradable plastics, producing bioplastics from common agricultural waste would create new revenue streams for farmers as well as the people who transport harvested feedstock and byproduct crops to refinery operations.

The key to bioplastic production is the efficient extraction and use of lignin, the organic polymer that is the primary structural support material in most plants. The new research takes five conventional pretreatment technologies for plant materials and modifies them to produce both biofuel and plastics together at a lower cost. The new method is called “plug-in preconditioning processes of lignin” and it can be directly and economically added into current biorefineries. The process is designed to integrate dissolving, conditioning, and fermenting lignin, extracting energy from it and making it easily adaptable to biorefinery designs.

The so-called bioeconomy currently supports some 286,000 jobs. Innovation is the key to achieving more widespread use of biodegradable plastic. With improved economics of so-called lignocellulosic biorefineries, there can be new avenues to use agricultural waste to produce biodegradable plastics.

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‘Plugging in’ to produce environmentally friendly bioplastics

Photo, posted November 5, 2015, courtesy of Kathryn Faith via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Conserving The Colorado River | Earth Wise

August 13, 2020 By EarthWise Leave a Comment

Last year, we talked about the troubles facing the Colorado River. Nearly two decades of drought conditions have reduced the water levels of the two largest reservoirs of Colorado River water and have threatened the water supply of millions of people in the region. Clear scientific evidence shows that climate change is constricting the iconic river and will do further damage as temperatures rise.

Faced with these facts, water resource managers have been implementing conservation policies in the region and the results so far are very encouraging.

The use of Colorado River water in the three states of the river’s lower basin – Arizona, California, and Nevada – fell to a 33-year low in 2019. The three states consumed just over 6.5 million acre-feet for the year, which is about 1 million acre-feet less than the three states are entitled to use under the legal agreement that allocates Colorado River water.

The last time water consumption from the river was that low was in 1986, which is the year that Arizona opened a large canal that extracts river water for its entitlement.

A key indicator of river health is the depth of Lake Mead, the largest reservoir of Colorado River water. It has been steadily dropping in recent years, but last year, with the reduced consumption, the water level actually increased by 12 feet.

According to water managers, the steady drop in water consumption in recent years is a sign that conservation efforts are working and that there are strategies that can deal with chronic shortages on the river in the future. It represents an important demonstration that it is possible to use less water in a region that irrigates 5 million acres of farmland and has 40 million people in 2 countries and 29 tribal nations.

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Remarkable Drop in Colorado River Water Use a Sign of Climate Adaptation

Photo, posted July 7, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Protecting Canola Crops From Frost

November 20, 2019 By EarthWise Leave a Comment

Canola is one of Canada’s most valuable crops. In fact, Canada is the world’s largest exporter of canola oil. The international market for canola oil is $27 billion a year. The oil is very popular because it has a relatively low amount of saturated fat, a substantial amount of monosaturated fat, and is very neutral tasting.

Canadian canola farmers worry a great deal about late season, non-lethal frosts because the frosts prevent chlorophyll – a photosynthetic pigment in the seeds – from breaking down, a process they call “degreening”. The farmers seek to have high-quality yellow embryos at seed maturity. When the harvest contains more than 2% of green seeds, it can no longer produce Grade No. 1 quality oil. When green seeds are processed to extract canola oil, the chlorophyll in the seeds reduces the oil’s storability and quality. As a result, farmers receive a lower price for frost-damaged green seed canola. This costs Canadian farmers and estimated $150 million annually.

Researchers at the University of Calgary have developed gene-based technology to produce canola plants that can withstand late-season frost and still produce high-quality seed. They identified a specific protein that controls chlorophyll breakdown and seed maturity. Genetic manipulation is able to enhance the seed degreening system. They were able to reduce the amount of chlorophyll in the genetically modified canola lines by 60% after the plants were exposed to non-lethal frost.

Ultimately, the researchers plan to develop a method to incorporate the modification into canola hybrid lines in such a way that it will be readily accepted by consumers concerned about genetically modified organisms.

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New technology helps protect valuable canola crops from frost

Photo, posted August 29, 2018, courtesy of Tinker and Rove via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Mexico’s Wonder Plant

September 13, 2019 By EarthWise Leave a Comment

In 1979, an American naturalist named Thomas Hallberg visiting a small town in Oaxaca, Mexico was amazed to find a type of local maize – or corn – that grew nearly 20 feet high in poor-quality soil even though the local farmers did not use any fertilizer.

The unique corn plant had aerial roots that grew a mucous-like gel just before harvest season. It seemed totally implausible, but the plant seemed to be fixing its own nitrogen: extracting it from the air and somehow making it useful to the plant.

In 1992, Hallberg returned with a group of Mexican scientists and collected samples to study in his lab. His research showed that the maize indeed received nitrogen from the air through its aerial roots. It took over 20 years to figure out what was going on in the plants. It turns out that bacteria that thrive in the low-oxygen environment of the maize’s mucus pulls nitrogen from the air and feeds it to the plant.

Scientists will probably spend years figuring out if a commercial application of this indigenous maize is viable. It isn’t guaranteed that the self-fertilizing trait of the plant can be bred into a commercial crop. But if it can, the payoff would be huge. Farmers spend more than $3 billion a year on corn fertilizer in the US alone.

A vexing problem is who should reap the financial benefits of the maize. The isolated village where the plant is grown has already signed an agreement to share in any such benefits. But there are other Oaxacan villages that also grow the plant.

Mexico’s wonder plant is likely to be caught up in the growing issue of biopiracy, which is the exploitation of indigenous knowledge and biological resources without permission.

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Indigenous Maize: Who Owns the Rights to Mexico’s ‘Wonder’ Plant?

Photo credit: ALLEN VAN DEYNZE/UC DAVIS

Earth Wise is a production of WAMC Northeast Public Radio.

Drilling In California

May 16, 2019 By EarthWise Leave a Comment

More than one million acres of public and private land in California may soon be opened up to oil drilling and hydraulic fracturing, according to a plan recently released by the Trump Administration. The proposal raises environmental concerns, and comes at a time when opposition to oil and gas drilling in the state is growing.

The plan, put forth by the Bureau of Land Management, would end a five-year moratorium in the state on leasing federal public land to oil and gas developers. In 2013, a federal judge put the moratorium in place until the environmental risks of hydraulic fracturing, or fracking, could be better evaluated.

Fracking is the process of injecting liquid at high pressure underground in order to crack open rocks and extract oil or gas. Well-documented risks associated with fracking include air and water pollution, as well as increased risks of oil spills and earthquakes.

Nevertheless, the Bureau of Land Management, which is part of the U.S. Department of the Interior, released its 174-page environmental impact statement with the proposal to open up 1,011,470 acres of land to fossil fuel extraction, impacting the California counties of Fresno, Kern, Kings, San Luis Obispo, Santa Barbara, Tulare, and Ventura.

Unsurprisingly, the draft plan has been praised by industry groups who say concerns are misguided, and slammed by environmentalists who say the move poses a serious public health risk and could lead to a “fracking frenzy.”

The proposal is now subject to a 45-day period for public comment, after which the Interior Department will determine how to proceed. A link to weigh in on the proposal can be found here .

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Trump fracking plan targets over 1 million acres in California

Bakersfield Field Office Hydraulic Fracturing Draft Supplemental Environmental Impact Statement

Photo, posted March 14, 2010, courtesy of Mike Baird via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Rare Earths From Mining Waste

May 3, 2019 By EarthWise Leave a Comment

The 17 rare earth elements have become important parts of much of modern technology. Despite their name, most of these elements are relatively plentiful in the earth’s crust, but because of their geochemical properties they are typically dispersed and not often found concentrated in minerals. As a result, economically exploitable ore deposits are uncommon. There are no significant sources in the U.S.

Rare earths play important roles in high-performance magnets, electric motors in vehicles, wind turbines, microphones and speakers, and in portable electronics like cell phones. As these applications become ever larger, the need for additional sources of rare earths increases.

Researchers at Idaho National Laboratory and Rutgers University have studied a method for extracting rare-earth elements from mining waste that could greatly increase the world’s supply of these valuable materials.

It turns out that large amounts of rare earths exist in phosphogypsum, a waste product from producing phosphoric acid from phosphate rock. The U.S. alone mined 28 million tons of phosphate rock in 2017. (Phosphoric acid is used in the production of fertilizers and other products).

The researchers estimate that more than a billion tons of phosphogypsum waste sits in piles at storage sites across the U.S. alone. World-wide, about 100,000 tons of rare earth elements per year end up in phosphogypsum waste. This compares to the total current world-wide production of rare earth oxides of 126,000 tons.

The researchers studied methods for extracting the elements from the waste. A method utilizing a common environmental bacterium showed great promise.

There are concerns about residual radioactivity and other environmental issues in dealing with the waste material, but the world’s supply of rare earth elements might become much greater based on this research.

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Critical Materials: Researchers Eye Huge Supply of Rare-Earth Elements from Mining Waste

Photo, posted June 19, 2015, courtesy of David Stanley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sand Mining And The Environment

April 2, 2019 By EarthWise Leave a Comment

In discussions of the environment, we don’t hear much about sand mining. But sand mining is the world’s largest mining endeavor, responsible for 85% of all mineral extraction. Sand and gravel are mined on a huge scale around the world. The UN estimates that the total exceeds 40 billion tons a year. Most of this activity is unregulated and unmeasured, and much of it is corrupt and environmentally destructive.

Concrete is the predominant use for sand. Every ton of cement requires six to seven tons of sand and gravel in order to make concrete. But sand also makes up 90% of asphalt on roads and it is used for land reclamation in places like Singapore. Sand is also widely used in industries such as glass manufacturing and fracking.

There are different sorts of sand. Desert sand is mostly useless for making concrete because its grains are too rounded by erosion and don’t bind well in the concrete. Marine sand is not great for concrete either because it has to be washed clean of corrosive salts.

As a result, salt miners mostly get sand from pits on land and dredged up from lakes and riverbeds. Dredging massive quantities of sand from rivers and lakes drastically alters river flow, erodes riverbanks, dries up tributaries, lowers water tables, and trashes wetlands and fisheries. In many countries, this even goes on in national parks where officials turn a blind eye to the activity. India is the world’s second-largest sand mining country (after China) and widespread illegal extraction occurs throughout the country run by highly organized and even violent “sand mafias.”

Sand mining is a huge problem and, to date, is one that is pretty much off of most people’s radar.

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