After looking at that site I expect that if I could find the author's full name and googled it, the results would be full of posts at metal detecting forums.
The whole site appears to be really bad advice-- instructing you to bury large metal containers of your valuable stuff on land that isn't yours. It is the stuff of detectorists fantasies.
> ..if I could find.. ..would be full.. ..fantasies.
Would you want to bet on how these guesses will pan out and see how this approach looks after sincere efforts to analyze it (for wealth preservation or other uses)?
> that site
There'rrr others worth looking at; probably others that contradict a good portion of it, or just have another point of view.
Well, you're still in luck.
You can search how to bury your stuff, ie:
http://www.howtoburyyourstuff.com/
Really.