The following information and documents were provided by Gene Willard on 21 Nov. 2004. Both documents were obtained via the "Declassified Documents Reference System". Note: Gene served as an Airborne Mission Supervisor (AMS) aboard Rivet Ball and Rivet Amber.
On 12 September 1957 the Director of Central Intelligence (DCI) briefed the National Security Counsel (NSC) on a "new Soviet ballistic missile test range between Tyrura Tam and Klyuchi", aka Klyuchi / Kura Test Range, on the Kamchatka Peninsula. The documents shown below may very well be the primary source that started the Rivet Ball and Rivet Amber program.