The Survival Guide To Long Term Food Storage: Part 5
It would be many times better to build some kind of underground room to store your long term food stash than to actually bury your buckets. Many buckets would permit small amounts of moisture into the bucket over many months or years. It actually wouldn't take a lot of moisture to make your dry packed food unusable.
Some folks who live in very hot or very cold climates sink 33 gallon trash barrels into the ground. A power auger does a great job of loosening up all of the dirt to do this, otherwise it is one heck of a tough hand shovelling task. you would need to place the bottoms of barrels three feet under the surface grade level. You leave only about an inch or two of the perimeter of the barrel above ground--just enough to fit the lid on securely. Obviously, you don't put the barrel or the hole it's meant to fit into out in the hot sun, especially in the warmer latitudes. The best place is in a covered spot that is shady, in a shed, etc.
Depending on your weather you may want to pile loose straw or hay on top of the barrel tops, or even some attic insulation will work: anything that minimizes the daily fluctuation of temperature. This works in both hot and cold climates. Folks in frigid areas often use these buried barrels as miniature cold cellars to store garden veggies, without processing, below the usual soil frost line in their region.
Keep in mind that these buried storage methods are in no way the optimal method for long term food storage. The best way to store grain for both the retention of the extremely valuable nutrients and for its future viability as seed is to subject the grain to subfreezing temperatures. It is extremely important to ensure that the grain must be extremely dry: the ideal level is 8% moisture. 10% is still acceptable but as soon as we start approaching the 15-20% mark, we run into problems.
These exceedingly low moisture levels are such a strong prerequisite to any stored grain because water expands as it freezes and forms ice crystals. If there is an excess of water left in the cytoplasm of the cells of the grain, the expanding crystals will skew the structure of the water containing molecules and can even rip the cell walls: effectively killing the seed. Once the seed has been frozen it is still acceptable for some food purposes. These grains would not be suitable for grinding in flour mills, but are generally boiled whole to serve as rice, orzo, or couscous substitutes, in soups, chowders, and other similar preparations.
Don't worry too much about requiring sensitive scientific instruments to measure the precise level of moisture in any particular grain. The general rules of thumb to ensure that the moisture level is low enough are:
Long seeds that are bent must break cleanly in half with an audible "snap" sound.
Corn and wheat seeds must shatter and turn into powder when smashed with a hammer.
Peas, beans and other large seeds must shatter, but not necessarily powder like corn.