Sure size is part of the issue, but it's also a issue of capacity. Most of our nuclear reactors are large because -- they're large. The expense only makes sense for large facilities, other than research. Also consider USN nukes for ship board use.
And its a TL-7 nuke? Considering the headache a TL-7 nuke brings, I can't imagine why someone would build one for power. They're neither handy, reliable, or portable, at least not for "wilderness" use. Not compared to, say, a diesel generator.
Now, clearly, fuel is an issue, but it begs all sorts of questions of how and why it got there, and who set it up?
What's powering the nuclear enrichment process to make the fuel? Why not use that instead?
Maybe you're talking about a modern "pebble" reactor, much safer to deploy. But, again, I would think it would have to be pretty cheap, especially compared to a fusion reactor or a diesel generator.
Because that's the nut. In the TU, Fusion is cheap, commodity, and plentiful. If you have a 100DTon starship, you have a Fusion reactor handy. Why not use one of those, and power it with sea water (along with a purification plant)?
Finally the real question is would the reactor put out enough of a signature that the Scout ship would see it, considering it's not looking for it. The sensors might pick it up, but is anyone really looking for it? Why would they be looking for activity on the poles anyway?
The guys that run Fission reactors are all nuclear scientists. We, today, don't have it down to a push button science. As a rule, we don't consider them "safe", not safe like a diesel motor is safe. Not safe where your Cousin Frank would fire one up to power the log splitter and leave it running while he ran off in to the woods behind a bush.
Obviously, later, Fusion power becomes "that safe" for whatever reason, as everything from the family car to every ship in the fleet has a fusion powerplant in it.
Rugged frontier outposts aren't in to nitty things like, oh, maintenance, or gauges, or whatever. They want simplicity and reliability. A hydro carbon power generator seems much more likely for that low tech level than a rogue nuke, IMHO. What ever is shipping product out can resupply the outpost with more fuel. 1 dTon of fuel is 3700 gallons. That's a LOT of fuel. Generators actually are rather thrifty with fuel, so 3700 gallons will run for quite some time. Found a 15000 watt generator that will run 6 months at 7500 watt load, 24hrs day on 3700 gallons.
Just a hell of a lot simpler than a nuke, and 15000 watts is a lot of power.
So, anyway I see a lot of logistical and expertise issues with a wilderness fission nuke, especially when efficient diesels exist, or even better, "Mr. Fusion".
o: 
