Bien Hoa

Another major hot spot is the heavily contaminated Biên Hoà airbase, where local residents continue to ingest high levels of dioxin through fish, chicken and ducks.

Remediation work to remove dioxin contamination was just getting started at the former Biên Hoà Air Base in Vietnam when USAID’s staff was dismantled in 2025.

One of the senators who signed the letter, Jeff Merkley, D-Ore., told ProPublica that abandoning the Bien Hoa cleanup is “a betrayal of the goodwill our two nations built over 30 years” and a “gift to our adversaries.”

With enough contaminated soil to fill about 40,000 dump trucks, the Bien Hoa air base is the largest deposit of postwar pesticides remaining in Vietnam after a decadeslong cleanup campaign.

The State Department said in a statement that the contracts at Bien Hoa are “active and running” but did not respond to detailed follow-up questions.