Mount Rushmore

N.J. Bud Goldstone <budgoldstone [at] yahoo__com> writes

>I do believe we may lose chunks of our one-of-a-kind mountain
>sculpture Mt. Rushmore to an unsafe "cleaning" operation. I don't
>know why high pressure wound up as the selected method other than it
>may have been the low bid, but my database says cleaning off lichen
>and mold should be done with a simple, cheap wash job. What was the
>the scientific backup that showed a blast was the way to go? Anyone
>know?

I don't know the answer to Bud Goldstone but I wondered why lichen
and mold are considered a problem on a mountain sized sculpture.
They may contribute marginally to biochemical erosion but could have
some beneficial effects against  weather too. Like Bud I would be
interested to know what technical and conservation assessment was
made. Does small loss of rock within this scale matter?

Simon


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                  Conservation DistList Instance 19:6
                   Distributed: Sunday, July 17, 2005
                        Message Id: cdl-19-6-007
                                  ***