In the thriving industrial city of Bien Hoa, about 20 miles east of Ho Chi Minh City, the former Saigon, there is a large air base, just beyond a sweeping bend in the Dong Nai River. During the American war in Vietnam, it was said to be the busiest airport in the world. Since the war ended in 1975, a dense cluster of four residential neighborhoods has grown up around the base. Their total population is perhaps 111,000, while the base itself, now home to advanced long-range fighter-bombers of the Vietnam People’s Air Force, has another 1,200 permanent residents.
A small drainage canal, no more than 8 or 10 feet wide, snakes its way from the west end of the runway — an area known as Pacer Ivy — for half a mile or so through one of these densely packed neighborhoods, which is called Buu Long. On a sweltering afternoon last month, toward the end of the dry season, the canal was no more than a stagnant greenish-brown murk strewn with garbage and choked in places with water hyacinths. Nonetheless, a middle-aged woman who introduced herself as Mrs. Mai was washing her hands and feet in the filthy water. Nearby, a fisherman was sitting on a low cement wall near the mouth of the canal. Nothing was biting.
The problem for Buu Long, however, is what couldn’t be seen. The canal is heavily contaminated with the most toxic substance ever created by humans: dioxin, the unintended byproduct of the defoliant known as Agent Orange, for the color-coded band on the 55-gallon barrels in which it was stored before being loaded onto the lumbering C-123 aircraft at the Bien Hoa base and sprayed over vast areas of Vietnam. During the U.S. Air Force campaign known as Operation Ranch Hand, Agent Orange was used to strip bare the coastal mangroves of the Mekong Delta and the dense triple-canopy forests that concealed enemy fighters and supply lines.