Dear Malinga, What i know about safe burial of faecal sludge, You excavate a pit and fill it in layers of about 30cm sludge. Make sure the pit is more than 1m above water table. Advisable to add lime every after a layer of sludge and little soil about 15cm. Final soil layer can be about 30cm thick. After burial i would advise you to ensure the area is above the surrounding groud level by about 5cm.
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