Ray K wrote:

Can anyone identify the problem on some of the cinder blocks at the base
of the outside wall of my garage? I'm wondering what the black stuff is.
It doesn't rub off, and it's unaffected by bleach. Photos appear on
alt.test at time 5:49 pm, 3/17/08.

Looks like grease or tar. Perhaps a previous owner did some engine work
there.

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Tony Sivori