Digging stash in the snow, makes it disappear since the stash text is missing from "types.xml".
I had to add this to make it work:

<type name="UndergroundStashSnow">

    <nominal>0</nominal>
    <lifetime>1814400</lifetime>
    <restock>0</restock>
    <min>1</min>
    <quantmin>-1</quantmin>
    <quantmax>-1</quantmax>
    <cost>100</cost>
    <flags count_in_cargo="0" count_in_hoarder="0" count_in_map="1" count_in_player="0" crafted="1" deloot="0"/>
</type>

And there are many bunkers in the game, that spawns the loot under the ground, and you can't reach it. I saw this in admin-tools on my server.
I am not talking about the bunker with the best loot, were you need glowplug to get into, I am talking about all the bunkers that is made out of concrete, and lyes under a snowy hill, of some sort.