The pencil and engineering design for mining

Mine site

On a series of flights to and from a distant mine, I read a great deal on the history and manufacture of the pencil. The book I read is called The Pencil and is by Henry Petroski a professor of civil engineering at Duke University. He writes regularly for the American Scientist; I follow his writings there and in his many other books on the design process in engineering.

As this is not a review of the book, I note only that he delves deep into the differences between a science, a craft, and engineering as reflected in the development of the pencil.

The point of this posting is the difference between craft and engineering in mining.

Craft may be said to be the routine making of things using the processes always used even if they were not consciously developed.

Conversely engineering involves a conscious act of intellect, involving knowledge, experience, art, and maybe the principles of science.

This difference was brought home to me most forcibly when on a mine site I once saw material (miscellaneous soils and rocks) being randomly dumped to form a run-of-mine pad for the ore stockpiles. I looked at the other geotechnical engineer on site with me, and in a word we both uttered “this will fail.” We needed no analysis, no calculation, just the briefest glance and each other’s confirmation.

But there was a problem: neither of us (from different countries and different companies) were engaged by our common client to advise on the new soil structure. We chatted a short while and decided that as professional engineers, albeit it members of very different cultures and societies, we were professionally obligated to raise our concerns.

We did. This set off a scurry with different folk on the mine seeking to respond in different ways: some prompted to protect past decisions; some prompted to cut costs; some determined to do what they had done many times elsewhere–without failure.

The rest of the story will have to await another time to tell. For now suffice it to say this became a fight between the craftsmen and the engineers.

Another similar incident occurred recently when I was shown the design drawings originating in Australia for a proposed new tailings facility. One look and my heart sunk: this design was just wrong from start to finish. Again no detailed examination was needed.  Just the pernicious old-man’s gut feel. The designers are friends. Again the outcome will have to await another time to tell, but it is a strain to have to tell friends they are craftsmen not engineers. For the drawings were beautiful and skilfully executed. It is just that the design was wrong.

I could draw lessons from this. But the kids are shouting to go down town to eat. So I end by remarking only this: read Petroski’s book and beware the routine application of craft in challenging mining situations.

For more from Jack Caldwell, see his blog, I Think Mining

Photo: Jack Caldwell