ERM-CC690 - Calcareous Soil

The material was collected at San Pellegrino Parmense (Italy) in February 1994, following a prospective study  of various sites in Italy which aimed at identifying a material with a reasonably high calcium carbonate content.  About 250 kg of soil was collected by shovelling from the surface to a depth of 10 cm (collection of top  layers). Stones and large plant litter were removed prior to sieving at 2 mm mesh. The fraction less than 2 mm  was collected in stainless steel trays in which the material was disposed in thin layers of a few cm thickness to  dry at ambient temperature. The material was sieved again after drying to remove lumps which were formed  during the drying process. The residual moisture content at this stage was found to be 3.8 % (measured by  taking a separate portion of 1 g dried at 105 °C until constant weight was attained). The sieved material was  transferred to a PVC mixing drum, which was then filled with dry argon, and was homogenised for 12 days at  about 48 rpm. The final material was manually bottled in brown glass bottles; the bottling procedure was  carried out by filling ten bottles, closing the drum and mixing the material again for 2 minutes before bottling ten  other bottles and so on, until only a few cm of soil powder remained in the drum (which was discarded). All  bottles, each containing 70 g of dry powder, were closed with an insert and a screw cap and stored at  ambient temperature.

keywords: environmental material , soil/sediment , rare earth elements , actinides