Tt some point we need to understand the mechanism better and use crude based on it’s production rate at the interface of the mantle and crust.
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I try to do my small part by dutifully returning my used oil to the ground
Used oil has a lot of uses there GH. Bar/chain oil for one, fuel, spot lubrication… to boot, most everything has lead free bearings now too, so it’s not a leaded haz waste for most part…