But this simple narrative—money enters river near jump zone, drifts downstream, deposits at Tena Bar—has been complicated by several pieces of analysis.
The first complication is the packet integrity. The bills were found in three packets, still bound by rubber bands, grouped together within a few feet of each other. This is not what you would expect of currency that had been tumbling freely through a river system for eight-plus years. Free-floating bills would scatter. Packets bound together might stay together longer, but the rubber bands alone should not have survived years of water exposure in good enough condition to hold the packets. The fact that the packets were intact and grouped suggests something different—perhaps burial or submersion in a protected environment for much of the intervening time.
The second complication is the location’s hydrological characteristics. Tena Bar is a deposit point on the Columbia River, a place where sediment accumulates. Some researchers have argued that the location is not a natural accumulation point for material originating upstream from the presumed jump zone, given the river’s current patterns and the position of Tena Bar relative to the major tributary inflows.
The third complication is the 2020 diatom study. Diatoms are microscopic algae that are carried in water and leave traces in sediment and organic material. The study, conducted by researchers who examined diatoms embedded in the Tena Bar bills, found a species composition more consistent with spring flooding patterns than with November 1971 river conditions. The interpretation offered by the study’s authors was that the bills may have entered the river system months after the hijacking—perhaps in spring 1972—rather than in November 1971.