sequestering

Using government support in the form of subsidies and tax credits, energy companies and others are planning to capture millions of tons of industrial carbon dioxide emissions and pipe the greenhouse gas into underground storage. It is a strategy enthusiastically supported by the fossil fuel industry because it allows them to keep burning the stuff.

There are currently 69 projects being reviewed by federal and state regulators seeking to store CO2 underground. The sorts of places where carbon dioxide can be injected are geologic zones containing porous rock formations which, in no way coincidentally, are the same places where oil and gas deposits are found. As a result, these places are studded with abandoned wells that have accumulated over the past century.

In Louisiana, there are about 120,000 abandoned wells that overlie geological zones that could store carbon dioxide. Environmental watchdog groups have identified numerous abandoned wells within a few miles of proposed storage sites.

The problem is that abandoned wells leak – even ones that have been plugged – and many haven’t been. The question is how much leakage will occur and what will be the consequences of the leakage. In Texas, pumping oilfield wastewater into abandoned wells has led to geysers of toxic water, artificial saline lakes, and earthquakes.

Underground carbon dioxide sequestering on a scale large enough to really matter will have to extend to very large areas. For example, injecting 100 million tons per year could create a pressurized zone as large as 100 miles. How large a problem this might create from abandoned wells in the zone is not at all clear but cannot be ignored.

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Companies Are Poised to Inject Millions of Tons of Carbon Underground. Will It Stay Put?

Photo, posted December 3, 2023, courtesy of Jason Woodhead via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Over the past few decades, research has identified the importance of large mammals like bison as ecosystem engineers. These animals shape and maintain various natural processes and, in the process, are responsible for the sequestering of large amounts of carbon. But large mammals – both herbivores and predators – have seen their numbers dwindle over time. At this point, nearly two-thirds of large carnivores are threatened with extinction. Overall, less than 6% of worldwide ecosystems have the extensive, intact large-mammal communities that were dominant 500 years ago.

Conservationists around the world have embarked on programs of “rewilding”- reintroducing large mammals into ecosystems. Some of the animals involved in these programs include brown bears, wild horses, jaguars, reindeer, Eurasian beavers, elk, moose, wolverines, tigers, hippos, and bison.

A group of bison raised in South Dakota have recently been transplanted to the Chihuhuan Desert at the US-Mexico border across Arizona, New Mexico, and Texas. There used to be huge bison herds in that region, but it has been largely bison-free for 150 years.

Perhaps more remarkably, wild bison are also being reintroduced into a forest near Canterbury, England. There haven’t been bison in the United Kingdom for thousands of years. But conservationists are introducing European bison into the British forest to knock down trees, trample shrubs, and create space for a greater diversity of flora and fauna.

Apart from the ecosystem goals of the British project, people in the UK, for the first time in over a thousand years, will be able to experience bison in the wild.

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Gone for Thousands of Years, Wild Bison Return to the UK

Photo, posted December 31, 2018, courtesy of Marco Verch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Storing carbon underground and abandoned wells

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Bringing Back Bison | Earth Wise

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