Multivariate factorial analysis to design a robust batch leaching test to assess the volcanic ash geochemical hazard

Abstract

A method to obtain robust information on short term leaching behaviour of volcanic ashes has been developed independently on the sample age. A Mixed Factorial Design

Assessment of leachable elements in volcanic ashfall: a review and evaluation of a standardized protocol for ash hazard characterization

“…Since 2005, eight studies (Table 2) have had other purposes such as comparing methods (Stewart and Leonard, 2018a); proposing new or modified methods (Ruggieri et al, 2012b;Gislason et al, 2011;and Hageman, 2007), reviewing ash leachate studies (Ayris and Delmelle, 2012; Stewart et al, 2006), carrying out retrospective analyses of published data (Ayris et al, 2015) or including leachate data as a supplement to a study with a different purpose (Borisova et al, 2013). Most are discussed elsewhere in this article so are not revisited here.…”

“…The rationale for this recommendation is discussed further in Section 3.3.1. Apart from cases where a range of contact times was applied (e.g., Ruggieri et al, 2012b;Bia et al 2019), only one study (Monick et al, 2013) adopted the contact time of 1.5 hours suggested in the Witham et al (2005) review. Studies utilizing longer contact times, and/or column leaching studies, will Journal Pre-proof J o u r n a l P r e -p r o o f 12 continue to be of interest when considering long-term impacts of the dissolution of glass or minerals of lower solubility.…”

“…Very short contact times would likely be unworkable because subsequent steps such as filtration create processing bottlenecks which could, in turn, lead to inconsistent contact times. Longer contact times (e.g., four or 16 hours) have proved to be unnecessary in studies where a range of contact times were applied, returning equivalent data to shorter duration leaches (e.g., Ruggieri et al, 2012b). Similarly, Hageman (2007) noted that mine waste samples analyzed by both the USGS Field Leach Test (which has a five-minute contact time) and USEPA Method 1312 (18±2 hour contact time) returned similar water-soluble concentrations of several major ions and trace metals.…”

An analysis of volcanic SO2 and ash emissions from Copahue volcano

“…Those authors examined ash samples with an ash/water ratio of 0.1:5 and agitation time (12 h) (Ruggieri et al, 2011), which is different from the methodology applied in this study. However, leached fractions are of the same order of magnitude and have the same trend as in the study by Ruggieri et al (2012). In their latter work, they tried different ash amounts (0.1 g and 1 g), different ash/water ratios (10, 25 and 50), and different agitation time (1.5, 4, and 16 h) for the leachate tests.…”

An Integrated Simulation, Inference and Optimization Approach for Groundwater Remediation with Two-Stage Health-Risk Assessment

“…The results presented that comprehensive analysis of PAT data was a powerful, cost-effective method for providing higher-resolution, value-added characterization of contaminated sites. Previous studies also applied many approaches such as dynamic programming [16], simulated annealing [17], artificial neural networks [18], genetic algorithms (GA) [19][20][21][22], robust optimization (RO) [23,24], and other techniques to improve remediation strategies. Evaluation of the merits for PAT remediation strategies is usually based on many factors such as contaminant concentration, the cost of PAT construction and operation, remediation duration, and health risk.…”