Preparation of shallow pits.
Select a site in the school compound where you can prepare a shallow pit or zai pit.
Dig a pit that is 60 centimetres long, 60 centimetres wide and 60 centimetre deep. Keep the topsoil aside and separate it from the subsoil.
If you have enough space, you may dig several pits in a row. Ensure that you leave a space of about 60 centimetres between any two pits.
Place light organic matter that can easily decompose at the bottom of each pit. Such materials may include dry grass and leaves collected in the school environment.
Add a layer of topsoil mixed with well decomposed manure or other types of manure such as sheep manure, cattle manure and poultry manure. Do not return the subsoil into the pit.
Leave a small depression of about 15cm to allow space for accumulation of water and to place mulching material.
Where the land is slightly sloping, put the subsoil on the lower side to make a semicircle around the shallow pit. The soil will help to trap runoff and concentrate it into the shallow pit.
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