One of the most difficult remediation challenges facing the U.S. Department of Energy (DOE) is the need to immobilize some 50 million gallons of highly ra-dioactive, liquid wastes stored in underground tanks at the Hanford site in Washington State. In part as a result of public participation, the technical strat-egy for tank waste treatment was revised in 1994: high-activity and low-activity waste fractions would both be immobilized in a vitrified glass form, although the low-activity fraction would remain at Hanford. This strategy has been subjected to cycles of reargument, reanalysis, and reconfirmation. As DOE proceeds with remediation of the Hanford tank wastes, it would be to the Department's advan-tage to understand that public participation has already made positive contribu-tions to technical decisions. © 2006 Wiley Periodicals, Inc.