Een keuringsmethode voor procesmatig gereinigde grond

Abstract

In the recently completed evaluation of the experiences with the Intron protocol for the testing of concentration levels in decontaminated soil it was concluded that this method does not meet the needs of its users. In connection with this conclusion in the present report a proposal is made for a new protocol. The basis for this protocol is a statistical procedure based on testing for a 99-percentile. The batch will be approved if 99% of the volume of the batch has a concentration level below accepted standard soil quality values. The proposed method has two steps. In most cases the first step will suffice. The dispersion of the results of this first step defines the necessary number of samples to perform the completion of the test in the second step. In the evaluation it appeared that detailed prescriptions for sampling and sample treatment were badly missed. For that reason these prescriptions are integrated with the proposed testing method. Sampling has to take place from the conveyor directly after the cleaning of the soil. To obtain the testsamples randomly chosen combinations of samples are combined and grinded under cryogene conditions. In the context of this project the protocol has been tested once in a remedial action to iron out possible faults and concluding that it was effectively formulated. The report concludes with some recommendations on remaining problems concerning the testing of cleaned soil.