Skip to main content

FIELD VERIFICATION OF ADVANCED TRANSPORT MODELS FOR RADIONUCLIDES IN HETEROGENEOUS SOILS.

Objective

THE RETARDATION OF CONTAMINANTS BY ADSORPTION ON SOIL COMPONENTS SUCH AS CLAY AND IRON OXIDES IS USUALLY THE MOST IMPORTANT MECHANISM THAT HAS TO BE TAKEN INTO ACCOUNT WHEN MAKING THE SAFETY ASSESSMENT OF A TOXIC LANDFILL, BE IT OF RADIOACTIVE COMPONENTS OR OTHER CHEMICALS. THE MOBILISATION OF THE RETARDATION CAPACITY IN ANY GIVEN SOIL PROFILE IS NOT ONLY A FUNCTION OF THE MASS OF ADSORPTION SITES BUT ALSO OF THE AVAILIBILITY IN THE FLOW SITUATION CONSIDERED. IN OTHER WORDS, THE EFFECTIVE RETARDATION CAPACITY IS A FUNCTION OF THE STRUCTURE OR HETEROGENEITY OF THE SOIL ON THE LENGTH SCALES RELEVANT TO THE PROBLEM. EARLIER STUDIES BY THE PRESENT RESEARCHERS, SUPPORTED IN PART BY THE EEC (PHASES I AND II) HAVE DEMONSTRATED THE KEY IMPORTANCE OF THESE PHENOMENA BOTH THEORETICALLY AND AT THE BENCH SCALES.
THE OBJECTIVE OF THIS STUDY IS TO VERIFY THE CONCEPTS DEVELOPPED IN THE EARLIER PROGRAMS AT A FIELD SCALE USING THE DATA GENERATED BY THE COMMUNITIES INVESTIGATION CONDUCTED BY THE BRITISH GEOLOGICAL SURVEY (BGS) AT DRIGG IN THE UNITED KINGDOM. WHILST THE STUDY IS DIRECTLY RELATED TO THE PROBLEMS ASSOCIATED WITH THE GEOSPHERE SAFETY ASSESSMENT TECHNOLOGIES FOR THE SHALLOW BURIAL OF LOW LEVEL RADIOACTIVE WASTE, THE PROBLEM DEFINITIONS, SOLUTION METHODOLOGIES AND PROBLEM SOLVING EXPERIENCE ARE DIRECTLY APPLICABLE TO ALL TOXIC WASTE AND CONTAMINANT MIGRATION STUDIES.

I. DATA COLLATION AND CRITICAL REVIEW.
II. PREDICTIVE MODELLING OF THE FIELD EXPERIMENT.
II.1 CALCULATIONS AT LEVEL 1 (HOMOGENEOUS APPROXIMATION).
II.2 CALCULATIONS AT LEVEL 2 (STRATIFIED APPROXIMATION).
II.3 CALCULATIONS AT LEVEL 3 (FULLY DETERMINATE CASE).
III. EVALUATION OF THE MODELLING EXERCISE.
III.1 INTER-MODEL LEVEL COMPARISON.
III.2 COMPARISON WITH THE RESULTS OBTAINED FROM THE DRIGG EXPERIMENTS.

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

Stichting Waterbouwkundig Laboratorium
Address

2628 CK Delft
Netherlands

Participants (1)

NERC British Geological Survey
United Kingdom
Address
Keyworth
NG12 5GG Nottingham