ANNEX II C SAMPLING AND ANALYSIS METHODS

ANNEX II C

SAMPLING AND ANALYSIS METHODS

1.   Soil sampling

The representative soil samples for analysis should normally be made up by mixing together 25 core samples taken over an area not exceeding 5 hectares which is farmed for the same purpose.

The samples must be taken to a depth of 25 cm unless the depth of the surface soil is less than that value; however, the sampling depth in the latter case must not be less than 10 cm.

2.   Sludge sampling

Sludge must be sampled after processing, but before delivery to the user, and should be representative of the sludge production.

3.   Methods of analysis

Analysis for heavy metals must be carried out following strong acid digestion. The reference method of analysis must be that of atomic absorption spectrometry and the limit of detection for each metal should be no greater than 10 % of the appropriate limit value.