Trace analysis and leaching dynamics of volcanic ash using NAA and ICP-MS

In 2010, Mt Merapi in Indonesia erupted releasing approximately 160 million tonnes of ash, roughly 75 % of which fell on or near Indonesia. With this extreme amount of a substance, even tract elements can become relevant. We have identified a variety of trace and major elements in this ash using instrumental neutron activation analysis. We have used a variety of techniques to improve our measurements, such as the use of epithermal neutrons and a Compton suppression system that resulted in accurate measurements of a wide range of trace elements including heavy metals. In order to better understand the leaching dynamics at which various elements can enter the local waters and have either enriching or toxic effects on the local ecosystem, we used a modified US Environmental Protection Agency Toxicity Characterization Leaching Procedure (TCLP) employing simulated rainwater.