First, here’s the Japanese video:
The original Nukey Poo was oficially named PM-A3. It went critical in 1963, was shut down in 1973, and finally dismantled in 1978. It was envisioned as a cheaper alternative to shipping diesel to the Antarctic station and was one of a handful of similar portable nuclear power plants placed in remote locations around the world. This article in the 1978 Bulletin of Atomic Scientists probably tells as complete a story as can be had in one source:
More information and photos are available in this post by Bill Spindler, the US Antarctic Program’s website, and in Rex A. Hoover’s story of his tour as a member of the reactor crew during the 1966 season.
The US Army in 1957 started work on a stationary low-power reactor prototype (SL-1) they hoped would power their remote facilities. The reactor was one of many at the National Reactor Testing Station (now Idaho National Lab). Though none of the documents I’ve found related to PM-3a mention SL-1, the 1961 meltdown of SL-1 killed the operators and required an extensive cleanup of the site. William McKeown details the story in his Idaho Falls: The untold story of America’s first nuclear accident. Though PM-3a and SL-1 were imagined for almost identical roles and purposes, and both are considered failures or disasters, PM-3a rates only a footnote in the DOE’s history of the National Reactor Testing Station.
This list of nuclear reactors may be interesting to some.