Modelling and simulation framework for reactive transport of organic contaminants in bed-sediments using a pure java object - oriented paradigm

Numerical modelling and simulation of organic contaminant reactive transport in the environment is being increasingly relied upon for a wide range of tasks associated with risk-based decision-making, such as prediction of contaminant profiles, optimisation of remediation methods, and monitoring of changes resulting from an implemented remediation scheme. The lack of integration of multiple mechanistic models to a single modelling framework, however, has prevented the field of reactive transport modelling in bed-sediments from developing a cohesive understanding of contaminant fate and behaviour in the aquatic sediment environment. This paper will investigate the problems involved in the model integration process, discuss modelling and software development approaches, and present preliminary results from use of CORETRANS, a predictive modelling framework that simulates 1-dimensional organic contaminant reaction and transport in bed-sediments

A web-based pesticide risk assessment tool for drinking water protection zones in Sweden

To protect human health, wildlife and the aquatic environment, " safe uses " of pesticides are determined at the EU level while product authorization and terms of use are established at the national level. In Sweden, extra precaution is taken to protect drinking water, and permits are therefore required for pesticide use within abstraction zones. This paper presents MACRO-DB, a tool for assessing pesticide contamination risks of groundwater and surface water, used by authorities to support their decision-making for issuing such permits. MACRO-DB is a meta-model based on 583,200 simulations of the physically-based MACRO model used for assessing pesticide leaching risks at EU and national level. MACRO-DB is simple to use and runs on widely available input data. In a qualitative comparative assessment for two counties in Sweden, MACRO-DB outputs were in general agreement with groundwater monitoring data and matched or were more protective than the national risk assessment procedure for groundwater

Applications of stable water and carbon isotopes in watershed research: Weathering, carbon cycling, and water balances

Research on rivers has traditionally involved concentration and flux measurements to better understand weathering, transport and cycling of materials from land to ocean. As a relatively new tool, stable isotope measurements complement this type of research by providing an extra label to characterize origin of the transportedmaterial, its transfer mechanisms, and natural versus anthropogenic influences. These new stable isotope techniques are scalable across a wide range of geographic and temporal scales. This review focuses on three aspects of hydrological and geochemical river research that are of prime importance to the policy issues of climate change and include utilization of stable water and carbon isotopes: (i) silicate and carbonate weathering in river basins, (ii) the riverine carbon and oxygen cycles, and (iii) water balances at the catchment scale. Most studies at watershed scales currently focus on water and carbon balances but future applications hold promise to integrate sediment fluxes and turnover, ground and surface water interactions, as well as the understanding of contaminant sources and their effects in river systems

GIS-and Web-based Water Resource Geospatial Infrastructure for Oil Shale Development

The Colorado School of Mines (CSM) was awarded a grant by the National Energy Technology Laboratory (NETL), Department of Energy (DOE) to conduct a research project en- titled GIS- and Web-based Water Resource Geospatial Infrastructure for Oil Shale Development in October of 2008. The ultimate goal of this research project is to develop a water resource geo-spatial infrastructure that serves as “baseline data” for creating solutions on water resource management and for supporting decisions making on oil shale resource development. The project came to the end on September 30, 2012. This final project report will report the key findings from the project activity, major accomplishments, and expected impacts of the research. At meantime, the gamma version (also known as Version 4.0) of the geodatabase as well as other various deliverables stored on digital storage media will be send to the program manager at NETL, DOE via express mail. The key findings from the project activity include the quantitative spatial and temporal distribution of the water resource throughout the Piceance Basin, water consumption with respect to oil shale production, and data gaps identified. Major accomplishments of this project include the creation of a relational geodatabase, automated data processing scripts (Matlab) for database link with surface water and geological model, ArcGIS Model for hydrogeologic data processing for groundwater model input, a 3D geological model, surface water/groundwater models, energy resource development systems model, as well as a web-based geo-spatial infrastructure for data exploration, visualization and dissemination. This research will have broad impacts of the devel- opment of the oil shale resources in the US. The geodatabase provides a “baseline” data for fur- ther study of the oil shale development and identification of further data collection needs. The 3D geological model provides better understanding through data interpolation and visualization techniques of the Piceance Basin structure spatial distribution of the oil shale resources. The sur- face water/groundwater models quantify the water shortage and better understanding the spatial distribution of the available water resources. The energy resource development systems model reveals the phase shift of water usage and the oil shale production, which will facilitate better planning for oil shale development. Detailed descriptions about the key findings from the project activity, major accomplishments, and expected impacts of the research will be given in the sec- tion of “ACCOMPLISHMENTS, RESULTS, AND DISCUSSION” of this report

Ground Water Surface Water Interactions in Texas

Groundwater-surface water interactions need to be evaluated to optimize water management in Texas. This study provides an overview of the impacts of groundwater-surface water (gw-sw) interactions on water quality and water quantity using available data. A literature review was conducted to assess the status of knowledge of gw-sw interactions. A total of 300 references were compiled. References were subdivided into those related to water quantity issues, water quality including point and nonpoint sources of contamination, and methods such as seepage and temperature approaches and modeling analyses. Additional topics covered by the reference list include impacts of climate variability and land use/land cover changes on gw-sw interactions and ecological issues. A compilation of data and information sources for assessing gw-sw interactions in Texas is also provided. This section includes web links to online report catalogs and databases and a listing of offline reports and catalogs provided by state and federal agencies.Bureau of Economic Geolog

Appraisal of Groundwater Flow Simulation in the Sub- Himalayan Watershed of Pakistan

Numerical modeling of an aquifer is increasingly used as a power tool for monitoring and management of groundwater. This paper focuses on conceptualizing hydrogeological condition and establishing numerical simulation model using Visual MODFLOW to simulate the continuous depletion of groundwater in the southwestern part of the Soan watershed in Pakistan. An integrated groundwater modeling and management approach was adopted to provide suitable alternatives for water management in different hydro-environments. Geospatial techniques were employed for spatial database development, integration with a remote sensing (RS), and numerical groundwater flow modeling capabilities to simulate groundwater flow behavior. The calibration results indicated a reasonable agreement between the calculated and observed heads. The calibrated heads were used as initial conditions in the transient-state modeling. The modeling approach facilitated in identifying potential groundwater regime besides providing artificial recharge options for sustainable groundwater development

Advancing the use of geographic information systems, numerical and physical models for the planning of managed aquifer recharge schemes

Global change is a major threat to local groundwater resources. Climate change and population growth are factors that directly or indirectly augment the increasing uptake of groundwater resources. To outbalance the pressure on aquifers, managed aquifer recharge (MAR) schemes are increasingly being implemented. They enable the subsurface storage of surplus water for times of high demand. The complexity of MAR schemes makes their planning and implementation multifaceted and requires a comprehensive assessment of the local hydrogeological and hydrogeochemical conditions. Despite the fact that MAR is a widely used technique, its implementation is not well regulated and comprehensive planning and design guidelines are rare. The use of supporting tools, such as numerical and physical models or geographic information systems (GIS), is rising for MAR planning but their scope and requirements for application are rarely reflected in the available MAR guidelines. To depict the application potential and the advantages and disadvantages of the tools for surface infiltration MAR planning, this thesis comprises reviews on the past use of the tools as well as suggestions to improve their applicability for MAR planning. GIS is not mentioned by most MAR guidelines as a planning tool even though it is increasingly being used for MAR mapping. Through a review of GIS-based MAR suitability studies, this thesis shows that the MAR mapping process could be standardized by using the often-applied approach of constraint mapping, suitability mapping by using pairwise comparison for weight assignment and weighted linear combination as a decision rule, and a subsequent sensitivity analysis. Standardizing the methodology would increase the reliability and comparability of MAR maps due to the common methodological approach. Thus, the proposed standard methodology was incorporated into a web GIS that simplifies MAR mapping through a pre-defined workflow. Numerical models are widely used for the assessment of MAR schemes and are included into some MAR planning guidelines. However, only a few studies were found that utilized vadose zone models for the planning and design of MAR schemes. In this thesis, a review and a subsequent case study highlight that numerical modelling has many assets, such as monitoring network design or infiltration scenario planning, that make its utilization during the MAR planning phase worthwhile. Consequently, this study advocates the use of vadose zone models for MAR planning by showing their potential areas of application as well as their uncertainties that need to be regarded carefully during modelling. Physical models used for MAR planning are typically field or pilot sites, as some MAR legislation requests pilot sites as part of the preliminary assessment. Laboratory experiments are used less often and are mostly restricted to the analysis of very specific issues, such as clogging. This thesis takes on the issue of scaling laboratory results to the field scale by comparing results from three physical models of different scales and dimensionality. The results indicate that preferential flow paths, air entrapment and boundary influence limit the quantitative validity of laboratory experiments. The use of 3D tanks instead of 1D soil columns and the application of statistical indicators are means to increase the representativeness of laboratory measurements. Nevertheless, physical models have the potential to improve MAR planning in terms of detailed process assessment, scenario and sensitivity analyses. All tools discussed in this thesis have their merits for MAR scheme planning and should be advocated better in MAR guidelines by depicting their application potential, advantages and disadvantages. The information accumulated in this thesis is a step towards an advanced use of supporting tools for the planning and design of MAR schemes.:1 Introduction 1.1 Motivation 1.2 Objectives 1.3 Structure of the thesis 2 Status quo of the planning process of MAR schemes 2.1 Guidance documents on general MAR planning 2.2 Application of GIS, numerical and physical models for MAR planning 2.3 Planning of surface infiltration schemes 3 Using GIS for the planning of MAR schemes 3.1 Implications from GIS-MCDA studies for MAR mapping 3.2 Development of web tools for MAR suitability mapping 4 Using numerical models for the planning of MAR schemes 4.1 Review on the use of numerical models for the design and optimization of MAR schemes 4.2 Planning a small-scale MAR scheme through vadose zone modelling 5 Using physical models for the planning of MAR schemes 5.1 Design of the experimental study 5.2 Comparison of three different physical models for MAR planning 6 Discussion and research perspectives 7 Bibliography 8 AppendixDer globale Wandel stellt eine große Bedrohung für die lokalen Grundwasserressourcen dar. Klimawandel und Bevölkerungswachstum sind Faktoren, die, direkt oder indirekt, die zunehmende Nutzung von Grundwasserressourcen verstärken. Um diesen Druck auf die Grundwasserleiter auszugleichen, werden verstärkt Maßnahmen zur gezielten Grundwasserneubildung (managed aquifer recharge = MAR) durchgeführt. Dies ermöglicht die unterirdische Speicherung von überschüssigem Wasser für Zeiten hohen Bedarfs. Die Komplexität von MAR-Anlagen macht ihre Planung und Umsetzung kompliziert und erfordert eine umfassende Bewertung der lokalen hydrogeologischen und hydrogeochemischen Bedingungen. Trotz der weltweiten Implementierung von MAR ist dessen Planung wenig reguliert. Umfassende Planungs- und Gestaltungsrichtlinien sind rar. Der Einsatz unterstützender Werkzeuge, wie numerischer und physikalischer Modelle oder Geoinformationssysteme (GIS), nimmt bei der MAR-Planung zu, aber ihre Einsatzmöglichkeiten und ihre Anforderungen an die Anwendung spiegeln sich selten in den verfügbaren MAR-Richtlinien wider. Um das Anwendungspotential und die Vor- und Nachteile der Werkzeuge für die MAR-Planung darzustellen, wurden für diese Arbeit Recherchen über den bisherigen Einsatz der Werkzeuge durchgeführt. Zusätzlich wurden Vorschläge zur Erhöhung ihrer Anwendbarkeit für die MAR Planung gemacht. Der Schwerpunkt lag dabei auf Oberflächeninfiltrationsverfahren. GIS wird in keiner MAR-Richtlinie als Planungsinstrument erwähnt, obwohl es zunehmend für die MAR-Kartierung eingesetzt wird. Eine Recherche über GIS-basierte MAR-Eignungsstudien zeigte, dass der MAR-Kartierungsprozess standardisiert werden kann mittels des oft genutzten Ansatzes: initiales Ausschneiden von Gebieten, welche Restriktionen unterliegen, dem folgend die Eignungskartierung mittels Paarvergleich für die Wichtung der GIS-Karten und der gewichteten Linearkombination als Entscheidungsregel, sowie eine abschließende Sensitivitätsanalyse. Die Standardisierung der Methodik könnte die Zuverlässigkeit und Vergleichbarkeit von MAR-Karten aufgrund des gemeinsamen methodischen Ansatzes erhöhen. Daher wurde die standardisierte Methodik in ein Web-GIS integriert, das über einen definierten Workflow die MAR-Kartierung vereinfacht. Numerische Modelle werden häufig für die Beurteilung von MAR-Systemen verwendet und sind in einigen MAR-Planungsrichtlinien ausgewiesen. Es wurden jedoch nur wenige Studien gefunden, die die Modelle der ungesättigten Zone für die Planung und Gestaltung von MAR Standorten verwendeten. Die in dieser Arbeit durchgeführte Literaturrecherche und eine darauf aufbauende Fallstudie zeigen, dass die numerische Modellierung viele Vorteile bietet, wie z. B. beim Design eines Monitoring-Netzwerkes oder bei der Planung von Infiltrationsszenarien. Physikalische Modelle, die für die MAR-Planung verwendet werden, sind meist Feld- oder Pilotversuche, da einige MAR-Gesetzgebungen Pilotstandorte im Rahmen der Vorabbewertung verlangen. Laborexperimente werden seltener eingesetzt und beschränken sich meist auf die Analyse sehr spezifischer Fragestellungen, wie z.B. der Kolmatierung. Diese Arbeit beschäftigt sich mit der Skalierbarkeit von Laborergebnissen auf die Feldskale, indem sie Ergebnisse aus drei physikalischen Modellen verschiedener Maßstäbe und Dimensionen vergleicht. Die Ergebnisse deuten darauf hin, dass Makroporen, Lufteinschlüsse und der Einfluss der Randbedingungen die quantitative Aussagekraft von Laborversuchen einschränken. Der Einsatz von 3D-Tanks anstelle von 1D-Bodensäulen oder von statistischen Indikatoren ist ein Mittel zur Erhöhung der Repräsentativität von Labormessungen. Nichtsdestotrotz hat die Anwendung physikalischerModelle das Potenzial, die MAR-Planung in Bezug auf detaillierte Prozessbewertung, Szenarien und Sensitivitätsanalysen zu unterstützen. Alle beschriebenen Instrumente haben ihre Vorzüge bei der Bewertung von MAR-Anlagen und sollten in MAR-Richtlinien detaillierter berücksichtigt werden, indem ihr Anwendungspotenzial, ihre Vor- und ihre Nachteile dargestellt werden. Die für diese Arbeit zusammengestellten Informationen sind ein Schritt zur Förderung der beschriebenen Planungsinstrumente für die Planung und Gestaltung von MAR-Anlagen.:1 Introduction 1.1 Motivation 1.2 Objectives 1.3 Structure of the thesis 2 Status quo of the planning process of MAR schemes 2.1 Guidance documents on general MAR planning 2.2 Application of GIS, numerical and physical models for MAR planning 2.3 Planning of surface infiltration schemes 3 Using GIS for the planning of MAR schemes 3.1 Implications from GIS-MCDA studies for MAR mapping 3.2 Development of web tools for MAR suitability mapping 4 Using numerical models for the planning of MAR schemes 4.1 Review on the use of numerical models for the design and optimization of MAR schemes 4.2 Planning a small-scale MAR scheme through vadose zone modelling 5 Using physical models for the planning of MAR schemes 5.1 Design of the experimental study 5.2 Comparison of three different physical models for MAR planning 6 Discussion and research perspectives 7 Bibliography 8 Appendi

Applying a statewide geospatial leaching tool for assessing soil vulnerability ratings for agrochemicals across the contiguous United States

A large-scale leaching assessment tool not only illustrates soil (or groundwater) vulnerability in unmonitored areas, but also can identify areas of potential concern for agrochemical contamination. This study describes the methodology of how the statewide leaching tool in Hawaii modified recently for use with pesticides and volatile organic compounds can be extended to the national assessment of soil vulnerability ratings. For this study, the tool was updated by extending the soil and recharge maps to cover the lower 48 states in the United States (US). In addition, digital maps of annual pesticide use (at a national scale) as well as detailed soil properties and monthly recharge rates (at high spatial and temporal resolutions) were used to examine variations in the leaching (loads) of pesticides for the upper soil horizons. Results showed that the extended tool successfully delineated areas of high to low vulnerability to selected pesticides. The leaching potential was high for picloram, medium for simazine, and low to negligible for 2,4-D and glyphosate. The mass loadings of picloram moving below 0.5 m depth increased greatly in northwestern and central US that recorded its extensive use in agricultural crops. However, in addition to the amount of pesticide used, annual leaching load of atrazine was also affected by other factors that determined the intrinsic aquifer vulnerability such as soil and recharge properties. Spatial and temporal resolutions of digital maps had a great effect on the leaching potential of pesticides, requiring a trade-off between data availability and accuracy. Potential applications of this tool include the rapid, large-scale vulnerability assessments for emerging contaminants which are hard to quantify directly through vadose zone models due to lack of full environmental data