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Series/Report no.
RIVM rapport 609021031Type
ReportLanguage
nl
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Validatie van het model DIVOCOSTranslated Title
Validation of the DIVOCOS modelPubliekssamenvatting
Het model DIVOCOS (DIspersion of VOlatile COntaminantS) is een bruikbaar model om een adequaat meetprogramma op te stellen waarmee tijdens een bodemsanering de luchtkwaliteit in de omgeving kan worden bewaakt. Dit concluderen we aan de hand van een validatiestudie van dit model.Met het model DIVOCOS kunnen de concentraties aan vluchtige stoffen in de lucht worden berekend die vrijkomen tijdens een bodemsanering. Het belangrijkste doel van deze berekeningen is te bepalen of en in welke vorm er tijdens de sanering metingen moeten worden uitgevoerd om de luchtkwaliteit in de omgeving te bewaken en eventuele blootstellingsrisico's van omwonenden te beperken. In deze studie hebben we gegevens verzameld van 10 bodemsaneringen om het model te valideren en de bruikbaarheid te beoordelen. We hebben het onderzoek gericht op acht stoffen, die verreweg het meest voorkomen in bodem- en grondwaterverontreinigingen in Nederland. De resultaten geven aan dat het model voor de meeste van deze stoffen concentraties in de leefomgeving berekent die redelijk goed overeenkomen met de gemeten waarden. Voor twee stoffen, beide met een relatief hoge dampdruk, vallen de berekende concentraties systematisch hoger uit dan de gemeten waarden.The computer model, DIVOCOS (DIspersion of VOlatile COntaminantS), calculates the concentrations of volatile compounds in air released during soil remediation. These calculations are primarily performed to determine whether air concentration measurements have to be carried out during the remediation in order to control the air quality and minimize possible health risks to residents. In this study we gathered data from 10 soil remediation processes to validate the computer model and assess its usefulness. Validation was performed on the compounds: benzene, toluene, ethylbenzene, xylenes, vinyl chloride, 1,2-cis-dichloroethene, trichloroethene and tetrachloroethene, all of which dominantly occur in soil and groundwater pollution in the Netherlands. The results of the validation show that for most of the compounds studied, the air concentrations calculated with the model compare well, at least in order of magnitude, with the measured values. The calculated concentrations of vinyl chloride and 1,2-cis-dichloroethene, however, appear to be systematically higher than the measured values. This is probably due to the high vapour pressure of these two compounds. In conclusion, DIVOCOS can be said to serve its main purpose: determining the necessity of taking air concentration measurements and defining an adequate measuring program during soil remediation.
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