67. Testing sludge.

67.     Testing sludge.

Every sludge producer1 must ensure that sludge produced by him and supplied for the purpose of use in agriculture2 is tested at intervals of not more than six months, and is also tested where changes occur in the characteristics of the waste water being treated3. Representative samples of sludge intended to be used on agricultural land must be taken after processing, but before delivery to the user4, each of which must be analysed so as to determine the pH value thereof5, the percentage content of dry matter, organic