This article’s intent is to get you to think ahead, so you do not find yourself having to cache survival supplies in the ground in the dead of winter but if you have to there are ways of doing it. The ideas and methods described are not ideal but can be accomplished.
The freezing depth or also known as frost depth or the frost line is something you have to consider when caching items in the ground, if they will be there during cold months. The freeze depth is the depth at which water would freeze.
In Minnesota for example the freeze depth is approximately 5 feet (1.5m) and in mid to Northern Missouri it would be 2.5 to 3.5 feet. In some parts, of Canada the freeze depth is close to 6 feet (1.8m). Soil composition and other factors will affect the freeze depth.
Research the area in which you have a cache or the area of the intended cache, so you know the depth you need to bury your supplies to protect them from the cold. Some people may have buried supplies in the summer without giving any thought to what the cold temperatures can do to the supplies.
Water of course has to be buried deep enough to prevent freezing as well as most canned goods. Certain medical supplies may be susceptible to cold temperatures as well, so before burying any caches make sure you know what can be frozen and not have it damaged from the freeze thaw cycles.
Digging a cache hole may not seem to strenuous sitting at home researching it all, but once at the site it is a different matter. It will take considerable effort and time to dig a hole up to six feet deep, even in the middle of summer.
Caches have to be carefully planned because the ground maybe snow covered when you arrive so detailed directions are necessary. Keep in mind GPS systems may not be operational so you must have map reading skills.
What if the Ground Is Frozen and You Need To Bury a Cache
Diesel or propane jet heaters can be used to thaw an area if you can attach piping to direct heat to the area. The area will have to be cleared of any snow and all ground combustibles. Have a metal rod that can be drove into the ground to check the thawing process. This method would require metal dryer vent tubing, or any metal tubing, heat resistant tape, large metal clamp (s) and an insulating blanket.
Cut a hole the size of the tubing in an insulating blanket, slide the tubing through and secure it with heat resistant tape. Then lay it over the area and place rocks on the corners to hold in place. The heat coming out of the tube will be contained over the frozen area by the blanket. Some jet heaters may have a small enough heat discharge tube to where the tubing could be clamped over the heating device using a large metal hose clamp. Run on the lowest setting. Obviously if you have an electric blower, power will need to be supplied.
Building a fire on top of the area is another idea but again time consuming and will of course give away your location. Sawdust layered over a small area can create enough heat to thaw the ground but again this is very time consuming.
The methods described will work to varying degrees and the thing you have to be concerned about is being discovered. Planning is important so you do not have to go to extremes to thaw the ground in the wintertime. Any work you do to thaw the ground would be easily discovered by anyone that happens to pass over the area.
Obviously, you want your supplies buried deep enough so you do not have to go back to the cache site to dig a deeper hole and hope you can avoid digging cache sites in the winter or look for alternatives to burying your cache.
Keep in mind if you do have a cache buried you can dig it up because the supplies have replaced the soil in the ground , so all you would have to do in most cases is break through the top layers of soil. You of course will not have to dig a hole, but simply uncover your supplies in the hole.