On the plan provided, draw the house drainage system (foul water) for a typical single stage 
septic tank.
The system is to include a septic tank, a distribution box, two separate absorption trenches
(effluent disposal), pipe work, bends, junctions, fittings, inspections and ventilation.
Each absorption trench is to be approximately 20 metres long.

PLEASE SEE PDF FOR IMAGE

Total 10 marks

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