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Quality assured field loss data sets for modelling - RP0118

The proposed project aims to provide data of high statistical validity on the procedd of particle 'field loss' from canopies of four generic crop types exposed to different rain fall conditions. Information on field loss rates is an important component of hazard evaluation models in the aftermath of nuclear emergencies. However, data derived from disparate literature sources often have unspecificed uncertainties and are of doubtful quality for modelling purposes. This project will develop a quality -assured approach to the acquisition of data intended for input to MAFF's SPADE model. Experiments will be use a novel combination of thermal generation of a uranium-based aerosol with delayed neutron counting as a highly sensitive detection technique.
1. To thermo-generate uranium aerosols and to detect by delayed neutron counting (DNC) using the Imperial College reactor and existing sample transfer facilities. This should provide 'part-per-trillion' sensitivity for uranium which in crops grown for experimetnal purposes has an extremely low background concentration. Large sample volumes can be accommodated with minimal preparation and rapid throughput. 2. To test aerosol generation, deposition and detection techniques using a simple and rapidly grown plant canopy -rye grass. 3. TO subject this 'testbed' canopy to an experimental regime involving exposure to or shelter from ambient environmental conditions or simulated rainfall. 4. TO optimise an experimental design which allows the application of analysis of co-variance to the data obtained. 5. To develop a quality assurance procedure together with documentation. 6. To derive discrete data sets for rye grass, wheat, beans/potatoes and cabbage/lettuce.
Time-Scale and Cost
From: 1993

To: 1995

Cost: £88,244
Contractor / Funded Organisations
University - London