01-01-2004, 08:42 PM
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Builders' sand for drainage?
The message
from (Nick Maclaren) contains these words:
The tens of thousands of years that's been there, any salt would have
been leached out, whatever the source.
If it was on the surface, yes. But there is a lot of salt underneath
Cheshire, that has not leached in millions of years. I could very
easily believe that many such deposits are mixtures of sand and salt,
and that there are places where salty sand is an accessible mineral
(and not near a current seashore).
I don't think sand at that depth would remain in free granular form, but
would be sandstone by now.
That salt in Cheshire has been there for a very long time, isn't very
close to the surface, and is, IIRC, sandwiched between two impervious
layers of rock.
So much sand lies at the surface that no-one is going to mine the stuff,
anyway.
--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
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