
Applying rock dust to croplands could absorb up to 2B tonnes of CO2 - dnetesn
https://phys.org/news/2020-07-croplands-absorb-billion-tonnes-co2.html
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aurizon
Mine waste of the correct kind will indeed absorb CO2. The rightn type can be
found as small particles and even nearly dust. However, some mine dust
contains toxic metals, Chrome, Arsenic, lead, copper in acidic form as acid
mine drainage. So what you spread on your crops or pasture or even waste land
must be chosen with care. That said, there is a lot of the right rock to make
a difference at only the cost of haulage.

[https://en.wikipedia.org/wiki/Acid_mine_drainage](https://en.wikipedia.org/wiki/Acid_mine_drainage)

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r16w
This is exactly what you have to worry about. There are innumerable amounts of
spoil tips and gob piles across the world but purifying the waste for use is
the real barrier to market leaving it ripe for exploitation by bad science and
business practices.

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dang
[https://news.ycombinator.com/item?id=23770718](https://news.ycombinator.com/item?id=23770718)

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tmaly
This would affect soil drainage and ruin valuable land. We would run into food
shortages.

