Evaluatie van ervaringen met de Intron-keuringsmethode voor gereinigde grond
Evaluation of the experiences with the Intron testing procedure for concentration levels in decontaminated soils
Bosman R, Versluijs CW, Lame FPJ
RIVM Rapport 738708003
In this report the results are described of the evaluation of experiences with the dutch standard testing procudre for decontaminated soils, deviced by Intron. The evaluation included a number of interviews with users of the method. In these intervieuws many problems evolved that were closely related to the testing of cleaned soils, i.e. sampling reference values, choice of values for the testparameters needed in the Intron procedure, acceptability of testing costs and the interpretation of the results of the chemical analysis at the detection limit. The lack of clarity in the field of quality assurance for decontaminated soils were the subject of discussion and critical remarks. The mentioned subjects are discussed in this report and the bottlenecks to be elaminated to obtain a manageable and generally acceptable testing procuedure for cleaned soils in the Netherlands are listed and explained. A statistical evaluation of the results of the Intron procedure shows that the determination of the number of samples to be analysed is not made on the basis of a correct statistical proceudre and that the parameters used for testing are not chosen in such a way that an unambiguous, uniform and logcal, legally defendable testing result can be obtained. It is recommended to device a new testing method.