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At present, the majority of water testing is carried out in the laboratory, and portable field methods for the quantification of elements in natural waters remain to be established. In contrast, portable instruments like portable X-ray fluorescence (pXRF) analysis and portable laser-induced breakdown spectroscopy (pLIBS) have become routine analytical methods for the quantification of elements in solids. This study aims to show that pLIBS can also be used for chemical compositional measurements of natural waters. Bottled mineral waters were selected as sample materials. A surface-enhanced liquid-to-solid conversion technique was used to improve the detection limits and circumvent the physical limitations in liquid analysis. The results show that low to medium mineralised waters can be analysed quantitatively for their ions using the documented method. For more highly concentrated samples, typically above an electrical conductivity (EC) of 1000 µS/cm, further adjustment is required in the form of self-absorption correction. However, water with a conductivity up to this limit can be analysed for the main cations (Li⁺, Na⁺, Mg²⁺, K⁺, Ca²⁺, and Sr²⁺) as well as the main anions (SO₄²⁻ and Cl⁻) using the documented method. This study demonstrates that there is significant potential for developing field-based pLIBS as a tool for quantitative water analysis.

At present, the majority of water testing is carried out in the laboratory, and portable field methods for the quantification of elements in natural waters remain to be established. In contrast, portable instruments like portable X-ray fluorescence (pXRF) analysis and portable laser-induced breakdown spectroscopy (pLIBS) have become routine analytical methods for the quantification of elements in solids. This study aims to show that pLIBS can also be used for chemical compositional measurements of natural waters. Bottled mineral waters were selected as sample materials. A surface-enhanced liquid-to-solid conversion technique was used to improve the detection limits and circumvent the physical limitations in liquid analysis. The results show that low to medium mineralised waters can be analysed quantitatively for their ions using the documented method. For more highly concentrated samples, typically above an electrical conductivity (EC) of 1000 µS/cm, further adjustment is required in the form of self-absorption correction. However, water with a conductivity up to this limit can be analysed for the main cations (Li⁺, Na⁺, Mg²⁺, K⁺, Ca²⁺, and Sr²⁺) as well as the main anions (SO₄²⁻ and Cl⁻) using the documented method. This study demonstrates that there is significant potential for developing field-based pLIBS as a tool for quantitative water analysis.

At present, the majority of water testing is carried out in the laboratory, and portable field methods for the quantification of elements in natural waters remain to be established. In contrast, portable instruments like portable X-ray fluorescence (pXRF) analysis and portable laser-induced breakdown spectroscopy (pLIBS) have become routine analytical methods for the quantification of elements in solids. This study aims to show that pLIBS can also be used for chemical compositional measurements of natural waters. Bottled mineral waters were selected as sample materials. A surface-enhanced liquid-to-solid conversion technique was used to improve the detection limits and circumvent the physical limitations in liquid analysis. The results show that low to medium mineralised waters can be analysed quantitatively for their ions using the documented method. For more highly concentrated samples, typically above an electrical conductivity (EC) of 1000 µS/cm, further adjustment is required in the form of self-absorption correction. However, water with a conductivity up to this limit can be analysed for the main cations (Li⁺, Na⁺, Mg²⁺, K⁺, Ca²⁺, and Sr²⁺) as well as the main anions (SO₄²⁻ and Cl⁻) using the documented method. This study demonstrates that there is significant potential for developing field-based pLIBS as a tool for quantitative water analysis.

At present, the majority of water testing is carried out in the laboratory, and portable field methods for the quantification of elements in natural waters remain to be established. In contrast, portable instruments like portable X-ray fluorescence (pXRF) analysis and portable laser-induced breakdown spectroscopy (pLIBS) have become routine analytical methods for the quantification of elements in solids. This study aims to show that pLIBS can also be used for chemical compositional measurements of natural waters. Bottled mineral waters were selected as sample materials. A surface-enhanced liquid-to-solid conversion technique was used to improve the detection limits and circumvent the physical limitations in liquid analysis. The results show that low to medium mineralised waters can be analysed quantitatively for their ions using the documented method. For more highly concentrated samples, typically above an electrical conductivity (EC) of 1000 µS/cm, further adjustment is required in the form of self-absorption correction. However, water with a conductivity up to this limit can be analysed for the main cations (Li⁺, Na⁺, Mg²⁺, K⁺, Ca²⁺, and Sr²⁺) as well as the main anions (SO₄²⁻ and Cl⁻) using the documented method. This study demonstrates that there is significant potential for developing field-based pLIBS as a tool for quantitative water analysis.

Despite looking back on decades of mine waste disposal practice, tailings dam failure disasters are still recurring fact today. In the woke of the latest major dam failures of Brumadinho (2019), Mariana (2015) and Mount Polley (2014), alternative disposal technologies are increasingly demanded to prevent failures in the future. One alternative approach is “Dry Stacking”, involving the deposition of mine waste in a relatively dry state. Lacking a central definition, and ‘dry’ being vague, this thesis aims to disentangle different and partly conflicting understandings of Dry Stacking and provide a more distinctive and comprehensive definition of Dry Stacking. The geographic distribution and different day-to-day practices of current and planned filtered tailings Dry Stacking projects in different mineral industries has been analysed and the findings presented. A Best Practice Guideline on how to successfully organise a filtered tailings Dry Stacking project has been developed. The Best Practice Guideline elaborates, how Dry Stacking of filtered tailings qualifies as Best Available Technology regarding tailings management and provides guidance on trade-off studies, waste characterisation, the planning and design phase, the operational phase and the closure phase. Finally, the Best Practice Guideline presents possible new approaches, which, in combination with Dry Stacking of filtered tailings, may have the potential to further improve the performance of the Dry Stacking technology. Ultimately, the future of the Dry Stacking approach is evaluated.

In recent decades, the interest in the responsible production of mineral resources has been growing due to legislative pressure or increasing media reporting on human rights violations and environmental issues related to mining. Customers are increasingly factoring ethical aspects into their purchasing decisions, which in turn leads to increased interest of manufacturers regarding the sustainability of their suppliers. Consequently, mining companies are increasingly seeking to ensure sustainability to obtain a competitive advantage. The rising demand in sustainability lead to the development of various third-party initiatives and certification schemes within the mining industry. Companies are confronted with the complexity and diversity and the growing costs due to investigations and implementations of various schemes, that technically overlap in many features. The Certification of Raw Materials (CERA) confronts the diversification within existing schemes and intends to become an all-encompassing standard. For that purpose, CERA developed the Application matrix that resembles a commodity specific database. The present thesis strives to evaluate the concept of the Application matrix for applicability and completeness using copper as an example. On the basis of a two-folded vulnerability analysis, targeting the structure and the content, the applicability and completeness of the initial matrix was refuted. Supplementary, the shortcomings and deficiencies were eliminated and the applicability, as well as the completeness in the context of copper was demonstrated with the adapted matrix. The compiled results were able to provide an evaluation of the necessity of certification for copper, which was affirmed.

The aim of this master thesis is to improve a raw materials certification scheme by checking and validating the application matrix and the coherent hazards developed for the Certification of Raw materials (CERA) project. The scope of the original application matrix included exploration, mining, physical processing, chemical processing, smelting and refining. The validation in this thesis was focussed on the iron ore value chain. This validation showed that important methods associated with these processes were missing in the application matrix. Two main sections that are absent are recycling and storage and transportation, which have been added to the application matrix including the main methods used within those two sections. The risks and hazards developed by CERA, associated with the application matrix’s processes and methods, are transformed to only hazards. Next to this, new hazards are suggested to make the hazards list more holistically applicable. After the addition of recycling to the application matrix, an analysis on the addition of recycling to the CERA Performance Standard (CPS) and to the CERA Chain of Custody Standard (CCS) was done. This analysis showed that adding recycling to the Performance Standard deals with few challenges due to it being an industrial activity with many similarities to methods used in processing and smelting. Therefore, with the additions that are proposed in the validation of the matrix and the hazards analysis, recycling can be easily added to the CPS. This is done by including collection centres, recycling facilities and scrap transport in the standard under the general term ‘recycling facilities’. Adding recycled material to the CCS can be done in different ways, this thesis proposes multiple options of which three are viable. First, three types of recyclable materials have been distinguished: Recyclables of which the origin is known (1); Recyclables of which the origin is unknown and no further information is available (2