Why re-invent the wheel? Your location in the world notwithstanding, there are hundreds of companies that design and install them for you. Besides, there are too many variables to cover in this forum (size, shape, depth, local codes, soil conditions, etc., etc.).
Good Luck
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People Living in Competition, All I want is to have my peace of mind - Boston
Well, it's the wrong place to learn about it, as indicated in #2↑.
This place is all about signposts.
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"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856