On this installment of ST, we speak by phone with the Pulitzer Prize-winning journalist Edward Humes, whose previous books include "Force of Nature" and "No Matter How Loud I Shout," and whose latest book, just recently out in paperback, is "Garbology: Our Dirty Love Affair with Trash." This book presents an unsettling yet fascinating and highly detailed profile of America's biggest export, its most prodigious product, and perhaps its greatest legacy: garbage.