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Support => exam support and downloads => Plumbing, Gas fitting and Drainlaying Apprentice Support => Drainlaying Exam June 2007 => Topic started by: LisaS on March 30, 2009, 08:59:05 PM

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Title: Question 4
Post by: LisaS on March 30, 2009, 08:59:05 PM

QUESTION 4
(a)   Describe a septic tank and state its purpose.
 
 
 
 
 
 
(3 marks)
(b)   Explain what is known as the cascade level in a septic tank.
 
 
(1 mark)
(c)   Explain the purpose of a sullage tank. 
 
 
(1 mark)
(d)  While installing a septic tank at a house under construction, a drainlayer discovers that
the water table is high. State what action the drainlayer should take to ensure that the
installation remains as laid.
 
 
(1 mark)

(e) Define the term absorption test.
 
 
 
(2 marks)
Total 8 marks

Title: Re: Question 4
Post by: Plumber on April 07, 2009, 10:11:40 PM

4 a) The septic tank is in effect a small sewage treatment plant. Used for disposal of all household wastes.

   b) Sewage enters the tank through a square junction and falls 75mm into the tank, the 75mm gap is known as the cascade level.

   c) A tank that receives the waste water from sinks, basins, baths, showers and similar fixtures but not liquid or solid excrement. (can be used to water the garden)

   d)

   e)