Coal's costs

I am writing in response to Pamela Zurer's editorial, "The Hidden Cost of Coal (C&EN, Jan. 16, page 3). In around 1960, as I recall, the administrator of the hydroelectric-happy Tennessee Valley Authority grandly pronounced, "The place for coal is in the ground."

Fortunately, a lot of coal has come out of the ground, and more will follow. The environmental and health costs are increasingly not only "tallied," as the editorial asks, but are internalized in the economics of the coal industry. I hope C&EN is not naive about that, too.

Richard A. Carpenter
Charlottesville, Va.

"The Hidden Cost of Coal" urges honestly tallying all the costs of fossil fuels. I agree. A photo from space shows a coal strip mine in Wyoming. Of course, this is very large and unattractive. What Zurer doesn't seem to realize is that the site will look like this only during the several-decade life of the mine. Under current Wyoming and federal regulations, coal strip mines must be reclaimed after the coal is removed.

Here's what this means: Typically there are 2 to 2.5 feet of thin topsoil, then 30 feet of overburden, and finally a coal seam 50 to 60 feet thick. In order to mine Area A, first the topsoil is scraped off and segregated. Then the overburden is removed to the previously mined Area B and leveled. The topsoil from Area A is then spread over the overburden. Finally, Area B is seeded with a prescribed mixture of native grasses.

Within a growing season, it's a high prairie again, albeit 50 feet or so lower than before. The antelope, elk, and other grazers appear not to notice. So while these may be "violent changes to our landscape mostly hidden from our sight," they are not permanent.

Speaking of honestly tallying costs, some time ago C&EN accompanied an article on new EPA regulations of emissions from coal-fired power plants with an untitled photo of a power plant emitting copious quantities of what looked like smoke. As a chemical engineer in the 1990s, I spent considerable time consulting at many coal-fired power plants. What with the scrubbers and electrostatic precipitators, I could barely see any visible stack emissions. Water vapor can condense, forming what are quite literally white clouds. But condensed steam is not a pollutant. Certainly there are potentially harmful emissions, but they are invisible.

Elliott P. Doane
Oklahoma City