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The big question for me is transportation of carbon dioxide to the sequestration site. Are carbon dioxide pipelines safe? What happens if they leak?

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founding

Mafic and ultramafic rocks lead to serpentine soils, which are common in California. Mafic and ultramafic rocks are going to be common near massive historic lava flows, the kinds you see in Eastern Washington and Oregon (not yet weathered into residuals like serpentines). These sources are appealing for all the rock-weathering techs, folks crushing olivine in the ocean are doing the "same" thing Carbfix is by leveraging a slow natural process at a relevant human scale. Serpentine soils is basically what is being formed by the mineralization of CO₂ from the injections. It has different physical properties, which should be of concern at large enough scale, and all that pumping has impacts, like the Sierras bending due to aquifer drawdown - so human scale water pumping does have above ground impact if you do enough of it - but a pretty good path all things considered.

We should generally be cautious about calling something permanent if it lasts 1,000 years - especially when we're using a natural rock weathering mechanism. In those future years when these rocks get exposed and would normally begin weathering to draw down atmospheric carbon we'll be running a natural drawdown deficit because they'll already be transformed. Granted, this is not a human-scale problem anymore, so it is effectively permanent, but one could have said the same thing about those pesky fossil fuels that humans found a way to get at and cause trouble with. This is much more of an issue with surface operations that produce active olivine or limestone rather than a deep injection - but if the sequestration isn't subduction grade (on a track to recycle down into the mantle) it just isn't permanent.

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Nov 11·edited Nov 13

I think that it is so great that all of the people that Dave interviews are making a worldwide contribution to beating climate change, especially Dave, himself. This pod is similar to the one where the scientist heated rocks that were on trays, which then absorbed the CO2 in the air and mineralized the carbon. However, this Icelandic company does not have to heat anything to get the same result.

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This is funny, because ever since I first heard about the idea of sequestering carbon underground, I wondered if it might turn our groundwater into Pellegrino...

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founding

The point of production vs. point of consumption accounting is important but not because one of the production path or consumption path is inherently more correct. It is important because when you have more than one accounting system for a globally shared resource you get shenanigans.

Drax gets 0 emissions credits for converting domestic UK coal fired power plants into American Wood Pellet consuming power plants that emit 3x more particulate and CO₂ than when they burned coal. All because the fuel has a point of origin requirement and the point of origin here is under a different regulatory regime (US vs. Europe).

The jobs analogy is a very bad model for the carbon credit - it should be called out not because the speaker was malicious or stupid to introduce it but because it feels useful and it really isn't (e.g. like the political tool of kitchen table economics: the Government isn't a family and doesn't have the same cash-flow considerations). There is no global consequence for the number of jobs, we could reconfigure society to have an arbitrary number of jobs (every human gets a job describing what they are doing for each second of every day, for instance) without consequence on anything but how humans record the activities of other humans. CO₂ has a global physical consequence and shifting the responsibility from company A to company B or country 1 to country 2 doesn't make sense when the impact is global and the countries and companies have different systems of record and compliance frameworks to manage the shared impact.

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"In fact, I read a report on groundwater in the US that said that it is an underutilized resource because it's only about 30% of the fresh water that is used in the United States is groundwater." Groundwater, surface waters and climate/weather are intrinsically connected and we are in many cases over extracting groundwater for Agriculture and other processes and is causing unintended consequences (certianly a large number of studies to support this). The questions is how is underutilized defined and what are the consequences from a water and ecological perspective if we continue to increase groundwater use.

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