Evaluation of selected static methods used to estimate element mobility, acid-generating and acid-neutralizing potentials associated with geologically diverse mining wastes

Abstract

a b s t r a c tA comparison study of selected static leaching and acid-base accounting (ABA) methods using a mineralogically diverse set of 12 modern-style, metal mine waste samples was undertaken to understand the relative performance of the various tests. To complement this study, in-depth mineralogical studies were conducted in order to elucidate the relationships between sample mineralogy, weathering features, and leachate and ABA characteristics. In part one of the study, splits of the samples were leached using six commonly used leaching tests including paste pH, the U.S. Geological Survey (USGS) Field Leach Test (FLT) (both 5-min and 18-h agitation), the U.S. Environmental Protection Agency (USEPA) Method 1312 SPLP (both leachate pH 4.2 and leachate pH 5.0), and the USEPA Method 1311 TCLP (leachate pH 4.9). Leachate geochemical trends were compared in order to assess differences, if any, produced by the various leaching procedures. Results showed that the FLT (5-min agitation) was just as effective as the 18-h leaching tests in revealing the leachate geochemical characteristics of the samples. Leaching results also showed that the TCLP leaching test produces inconsistent results when compared to results produced from the other leaching tests. In part two of the study, the ABA was determined on splits of the samples using both well-established traditional static testing methods and a relatively quick, simplified net acid-base accounting (NABA) procedure. Results showed that the traditional methods, while time consuming, provide the most in-depth data on both the acid generating, and acid neutralizing tendencies of the samples. However, the simplified NABA method provided a relatively fast, effective estimation of the net acid-base account of the samples. Overall, this study showed that while most of the wellestablished methods are useful and effective, the use of a simplified leaching test and the NABA acid-base accounting method provide investigators fast, quantitative tools that can be used to provide rapid, reliable information about the leachability of metals and other constituents of concern, and the acidgenerating potential of metal mining waste.Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Mineralogy and geochemical investigation of Cambrian and Ordovician–Silurian shales in South China: Implication for potential environment pollutions

“…Similarly, pyrite can also react with the hydraulic fracturing fluids (contain oxidized substance) to produce acidic solutions. These acidic solutions can corrode equipments or mobilize toxic trace elements, which solute in fracturing flow‐back fluids (Hageman, Seal, Diehl, Piatak, & Lowers, ; Chen & Carter, , ; Yang, Wang, et al, ). Therefore, the fracturing flow‐back fluids may impact the environment and wellness of humans if they are not regulated correctly.…”

“…Mineralogical data allow us to evaluate the general behaviour of shales when they outcrop at the surface. Several studies reported acid generating, acid neutralizing, and trace elements mobilization from sulphide oxidation in mining impacted water (MIW; Hageman et al, ; Joeckel, Ang Clement, & VanFleet Bates, ; Seal, ). Reactions (), (), and () above are very important to reflect acid generation and neutralization even if these reactions do not consider the kinetic effects of pyrite oxidation and calcite dissolution, which are important to evaluate and predict the hydrogen ions or acid rock drainage (ARD; Rimstidt & Vaughan, ; Williamson & Rimstidt, ).…”

Commercial utilization of mineral waste - review of analysis methods determining its compliance with environmental laws

“…Depending on the needs, tests with various complexity levels can be used, from the simplest -the leaching test, which is unfortunately the least informative one, to the most complicated and time-consuming four-and six-step methodologies, which can also provide most data on the types of binding and mobility of particular components. The TCLP test seems to be most appropriate to simulate the conditions of a long-term leaching that waste materials in a landfill are exposed to (Shieh 2001, Hageman et al 2015 and best for organic contaminations. The SPLP test is preferred when the content of metals in a sample is analysed because of a lower pH and lack of complexing agents in the extraction liquid (Lackovic et al 1997).…”

“…The SPLP test is preferred when the content of metals in a sample is analysed because of a lower pH and lack of complexing agents in the extraction liquid (Lackovic et al 1997). This test is much more suitable for leaching simulations where the leaching agent is applied directly before the leaching process, as it is the case with precipitation (Hageman et al 2015).…”

Geoquímica y mineralogía de los jales del distrito minero Tlalpujahua-El Oro, México, y sus implicaciones de impacto ambiental

“…generación de H + ), el cual puede estar asociado con iones de sulfato ) y hierro (Fe +2 /Fe +3 ) en un sistema de soluciones ácidas, conocidas como Drenaje Ácido de Mina (DAM; Blowes y Jambor, 1994;Moncur et al, 2005;Blowes et al, 2014), que a su vez favorece la movilidad en solución de los EPT en un sistema hidrológico (Plumlee, 1999). En contraparte, durante el mismo proceso de intemperismo de un jal se llevan a cabo otro tipo de reacciones que pueden generar una relativa neutralización, ya sea por el consumo de iones H + o incluso, si su proporción es dominante, pueden generar un sistema no-ácido o alcalino (Jambor y Blowes, 1998;Hageman et al, 2015). En todo caso, el balance de las reacciones de acidez y neutralización de intemperismo en los jales, son atribuidas a la desestabilización de los minerales primarios, ya sea como formadores de roca (silicatos, carbonatos) o inherentes al depósito mineral (ganga o mena), los cuales dan lugar a la formación de minerales secundarios, que pueden precipitar, inhibir y/o neutralizar el sistema durante los procesos de intemperismo (Jambor 2003;Paktunc, 1999;Jamieson et al, 2015).…”