RAPID SOIL ANALYSES OF OVERBURDEN MATERIAL FROM HISTORIC MINES WITH SNMS

Plasma-based Secondary Neutral Mass Spectrometry (SNMS) is designed an d usually used for depth-resolved determination of the elements in inh omogeneous samples. This report shows that it is also advantageous for the quantification of the total elemental inventory of granular mater ial. As an example of such an application, the quantitative elemental analysis of soil samples from residues of three historic mines in Bade n-Wurttemberg is presented. The results obtained with SNMS, using a hi gh primary energy of E-p = 1340 eV, were compared to the concentration s measured by Atomic Absorption Spectroscopy (AAS) and X-Ray Fluoresce nce (XRF). A reasonable correspondence was found with a mean deviation between all three methods of about 50%. However, SNMS measurements of standard soils, without any matrix adaptation of the elemental sensit ivities, exhibited mean deviations from the certified concentrations o f only 20-30 wt% down to concentrations below 10(-2) wt%. The advantag es of SNMS against AAS and XRF are its simple sample preparation and t he rapid detection of all elements in the analyzed material within som e 10 min. In each of the three samples chromium, nickel, copper, zink and lead (only sample HS 64) were found in concentrations exceeding th e limiting values of the German Sewage Sludge Ordinance (SSO).