This research project evaluated the overall hydroperiod and effects of monitoring well design parameters on observed levels of saturation in created wetlands with high-clay subsoils at the Cedar Run 3 mitigation bank site in Prince William County, Virginia. Three complete replications of an electronic central array and an associated surrounding array of manually monitored wells and piezometers were installed. The electronic arrays contained a U.S. Army Corps of Engineers (USACOE) standard monitoring well, as well as piezometers and tensiometers at three depths. The manually monitored well + piezometer arrays (3 per location; 9 total) consisted of 12 variants of screen types and filter pack materials, well diameter, and unlined bore holes. The site exhibited a complex seasonal hydroperiod ranging from ponded winter conditions to deep (< -50 cm) summer dry down. The site also exhibited epiaquic (perched) conditions following summer and fall precipitation events. Apparent water levels in deep (> 1 m) piezometers exhibited an unusual hydroperiod with highest levels in summer. Differences in well/piezometer diameter, design, and packing texture/fit produced surprisingly different apparent water levels that varied from ~ 4 to over 28 cm during both the winter ponded periods and summer subsoil water table flux periods. Thus, one important finding is that relatively simple differences in well designs can have dramatic effects on observed water levels. Overall, the standard USACOE appeared to be relatively accurate for predicting saturation levels during ponded periods, but nested piezometers are preferred and more accurate for the drier summer and fall. / Master of Science

Die Schriftenreihe gibt in 11 Fachbeiträgen die Ergebnisse aktueller Projekte und Forschungsvorhaben des LfULG wieder. Die Themen sind breit gefächert und beinhalten beim Grundwasser die Nitratbelastung an der Wasserfassung Diehsa, das Vorhaben eines digitalen Hydroisohypsenplanes in Sachsen, Sensor- und Thermo-Flowmetermessungen für den Ersatz von Grundwasseraufschlüssen sowie Informationen zum Projekt KLIWES mit Abschätzung der Auswirkungen der Klimaveränderungen auf den Wasserhaushalt in Sachsen. Die Themen des Altlastenbereiches umfassen neben dem Sächsischen Altlastenkataster die Schwerpunkte Sickerwasserprognose, Resorptionsverfügbarkeit von Schadstoffen aus Böden der Erzgebirgsregion, die Flutung der Grube Königstein und Informationen zum Projekt SUMATECS zur Anwendung sanfter Sanierungsverfahren. Die Vernetzung der einzelnen Fachdisziplinen wie z. B. bei Klimaänderungen oder der EU-Wasserrahmenrichtlinie (WRRL) spielt dabei eine immer größer werdende Rolle. »Grundwasser - Altlasten aktuell« erscheint mit dieser Ausgabe erstmals als Heft der Schriftenreihe.

Oman faces a water resources crisis as the demand of fresh water increases day by day. Most of the renewable water resources in the country are directly or indirectly dependent on the rainfall. The Western Hajar Mountains extend to the borders with the UAE. This area is a very important source of ground water for both countries. A collaborative program to investigate the feasibility of rainfall enhancement over the Omani mountains by means of hygroscopic cloud seeding was implemented in the UAE during the summer of 2003 and 2004. Due to the complicated logistics and astronomical cost involved in the cloud seeding experiment, it is crucial that timely and accurate forecasts are made for these mesoscale storms. However, convective clouds of the Al Hajar Mountains are notoriously difficult to predict as they result from mesoscale circulation. This study developed forecasting techniques for seedable storms over the Western Hajar Mountains in the Sultanate of Oman. A period of 10 days (5th-14th of July 2004) was investigated in order to describe the differences in the atmospheric parameters between days when convection occurred and days which remained dry. The main ingredient for convective development is the influx of surface moisture from southeast over the Arabian Sea. This moisture often results from the circulation around the surface low over the central part of the Arabian Peninsula but may occasionally be caused by the sea breeze circulation. The northeasterly sea breeze moves in from the Gulf of Oman to the mountains where it converges with the southeasterly moist flow and this may result in the occurrence of convective clouds. Localized wind convergence zones near the mountains are good indicators of the onset of convection. The Oman Convection Index (OCI) was developed to replace the K-index (KI) and was found to provide a good indication of convective development over the mountains. A forecasting decision tree table for predicting convective storms over the Al Hajar Mountains is proposed where circulation criteria are stipulated as well as critical values for meteorological variables. The ingredients includes the location of the heat low over the centre of Arabian Peninsula, latent instability of the atmosphere, and critical values of mixing ratio and the OCI. This research results have shown that careful investigation and manipulation of the available data allow for increased accuracy in the forecast of convection. The OCI was developed to describe the conditions favorable for summer convection over the mountains of Oman specifically. The results show that the OCI fairs considerably better than the KI in identifying days when significant convection is likely to occur. However, the OCI is only one element of the forecasting techniques table. For truly significant convection to occur there are at least four other circulation criteria which should be satisfied. The forecasting decision tree table provides a systematic approach to the forecasting of convection of the mountains and therefore, for the first time in Oman, objective verification is possible and opens the door for improving these and other forecasting techniques. The techniques developed here may therefore contribute to future cloud seeding projects in the mountains of Oman. / Dissertation (MSc)--University of Pretoria, 2007. / Geography, Geoinformatics and Meteorology / MSc / Unrestricted

In situ chemical oxidation (ISCO) using permanganate has been increasingly applied to deplete mass from dense nonaqueous-phase liquid (DNAPL) source zones. However, uncertainty in the performance of ISCO on DNAPL contaminants is partially attributable to a limited understanding of interactions between the oxidant, subsurface hydrology, and DNAPL mass transfer, resulting in failure to optimize ISCO applications. To investigate these interactions, a factorial design experiment was conducted using one-dimensional flow through tube reactors to determine how groundwater velocity, permanganate concentration, and DNAPL type affected DNAPL mass depletion rates. DNAPL mass depletion rates were found to increase with increasing groundwater velocity, or increasing oxidant concentration. An interaction occurred between the two factors, where high oxidant concentrations had little impact on mass depletion rates at high velocities. High oxidant concentration systems experienced gas generation. Mass depletion rates were fastest at high velocities, but required additional oxidant mass and pore volume addition to achieve complete mass depletion. Lower-velocity systems were more efficient with respect to oxidant mass and pore volume requirements, but mass depletion rates were reduced.

This paper describes laboratory studies conducted to evaluate the impact of varying environmental conditions (dense non-aqueous phase liquid (DNAPL) type and mass, and properties of the subsurface porous media) and design features (oxidant type and load) on the effectiveness and efficiency of in situ chemical oxidation (ISCO) for destruction of DNAPL contaminants. Porous media in 160 mL zero-headspace reactors were employed to examine the destruction of trichloroethylene and perchloroethylene by the oxidants potassium permanganate and catalyzed hydrogen peroxide. Measures of oxidation effectiveness and efficiency include (1) media demand (mg-oxidant/kg-porous media), (2) oxidant demand (mol-oxidant/mol-DNAPL), (3) reaction rate constants for oxidant and DNAPL depletion (min-1), (4) the percent (%) DNAPL destroyed, and (5) the relative treatment efficiency, i.e., the rate of oxidant depletion versus rate of DNAPL destruction. While an obvious goal of ISCO for DNAPL treatment is high effectiveness (i.e., extensive contaminant destruction), it is also important to focus on oxidation efficiency, or to what extent the oxidant is utilized for contaminant destruction instead of competing side reactions, for improved cost effectiveness and/or treatment times. Results indicate that DNAPL contaminants can be treated both effectively and efficiently under many environmental and design conditions. In some cases, DNAPL treatment was more effective and efficient than dissolved/sorbed phase treatment. In these experiments, permanganate was a more effective oxidant, however catalyzed hydrogen peroxide treated contaminants more efficiently (e.g., less oxidant required per mass contaminant treated). Results also indicate that oxidation treatment goals can be dictated by environmental conditions, and that specific treatment goals can dictate remediation design parameters (e.g., faster contaminant destruction was realized in catalyzed hydrogen peroxide systems, whereas greater contaminant destruction occurred in permanganate systems). Journal of Environmental Engineering

Pineview Reservoir, near Utah's populous Wasatch Front, could play an important role in modulating water supply as water demands and water uses change in response to increasing population densities. The reservoir is currently mesotrophic but threatens to become eutrophic. Ground water in the shallow water table aquifer that surrounds the reservoir contributes a large proportion of the reservoir's inflows in summer and fall because most of the stream flow is diverted for irrigation. Ground water flow and its subsequent nutrient loading to the reservoir were studied from February 2010 through November 2011. The objectives were to: 1) characterize nutrient transport from the water table aquifer to the reservoir; 2) quantify and characterize the spatial variability of ground water flow and nutrient loading in a mountainous irrigated valley; and 3) estimate nitrate leaching to ground water from cropland, lawns and septic drain fields. The first objective was achieved by monitoring stream flows, and modeling ground water flow and nutrient loading towards Pineview Reservoir. Ground water from the water table aquifer contributed 22 percent and 2.6 percent nitrate + nitrite nitrogen and total dissolved phosphorus, respectively, to the annual reservoir loads. The aquifer contributed a total inflow of 3.4 x 106 m3 yr-1 (2 percent of the total inflows) to the reservoir. Large variations in both ground water nutrient concentrations (6 - 310 µg P L-1 as total dissolved phosphorus and 3.3 - 21 mg N L-1 as nitrate + nitrite) and ground water flows among aquifer subdivisions were observed. Study of the second objective employed GIS-based interpolation techniques in analyzing the spatial distribution of ground water flow and nutrient loading towards the reservoir. Large spatial variations in ground water flows and nutrient loadings were observed. The 67 percent confidence intervals (geometric mean ± 1 standard deviation) for total dissolved phosphorus ranged from 0.014 - 0.400 kg P d-1. Nitrate + nitrite nitrogen had a 67 percent confidence interval of 0.954 - 39.1 kg N d-1. The variations were attributed to agricultural and domestic non-point sources. Under the third objective, ground water nitrate loadings in the near-reservoir drainage area of the reservoir's major tributary, the South Fork of the Ogden River, were simulated in the GIS-based Nitrogen Loss and Environmental Assessment Package. Annual leaching rates (kg N ha-1 yr-1) from drain-fields and the lawns were, respectively, more than 2.6- and 1.1-fold higher than the croplands. However, differences in the spatial extent of contributing sources resulted in 70- and 50-fold higher total leaching losses from croplands and lawns, respectively, than drain-fields. The findings would help water managers, town planners, and stakeholders in their decisions relative to land use, water distribution and use to protect and/or improve water quality in the reservoir.

The aqueous geochemistry and hydrology of the North Fork of the American Fork River, its tributaries, and the ground water in the vicinity of the Pacific Mine site were investigated in order to determine what impact ground water entering the North Fork has on toxic metal loads in the river. Toxic metal contamination in the North Fork is great enough that brown and cutthroat trout have absorbed lead, cadmium, and arsenic in their tissues at concentrations that are hazardous to human health if consumed. Ground water that flows through the mine site flows directly through the mine tailings before entering the North Fork, which produces an acidic ground water plume that has high concentrations of toxic metals. Together, the surface water discharge results and toxic metals concentrations from the surface and ground waters were used to determine toxic metals loading rates in the North Fork and its tributaries. The results suggest that the dissolved toxic metals (As, Cd, Cu, Fe, Mn, Pb, and Zn) enter the North Fork when the river is gaining water from the ground water. However, the total toxic metal load generally decreases through the reach of river adjacent to the mine site and is significantly greater than the dissolved load. Cadmium and Mn travel as dissolved species while Cu, Fe, Pb, and Zn travel as suspended solids in the North Fork and its tributaries. Arsenic seems to be associated with both the suspended solids and travel in the dissolved state. The geochemical modeling program PHREEQC and the diffuse double layer surface complexation model were used to investigate the chemistry that controls toxic metal mobility and attenuation in the surface and ground waters at the mine site. Based on PHREEQC results, the most important reaction in these waters is the precipitation of hydrous fe1Tic oxide. The toxic metals that sorb to the hydrous ferric oxide are Cu, Pb, most importantly Zn, and to a lesser degree As.

As part of a U.S. Geological Survey study in Juab Valley in central Utah from 1991 to 1994, the chemistry of ground - and surface -water samples was determined. Total dissolved solids in the ground water of southern Juab Valley have historically been higher , in general, than ground water in other areas of Utah . Total dissolved solids for ground-water samples from this study ranged from 623 to 3,980 milligrams/liter. High-sulfate chemical data of previous studies suggested that the major source of ground-water salinity is the dissolution of gypsum (hydrous calcium sulfate ) from the Arapien Shale. Sulfur-34 to sulfur- 32 isotopic ratio data have confirmed that dissolved Arapien Shale is the major source of salinity in southern Juab Valley water. This thesis study of southern Juab Valley had four main objectives: 1) define the present chemistry of the ground and surface water; 2) qualitatively determine the mineralogy of the Middle Jurassic Arapien Shale; 3) determine the major sources of salinity; and 4) determine the main flow path in the ground-water system. Chemical data show that the water in southern Juab Valley is predominantly of a calcium-magnesium-sulfate-bicarbonate composition. X-ray diffraction determined the mineralogy of the Arapien Shale as primarily calcite and quartz. Mineralogy of the acid-insoluble residue is illite, chlorite, quartz, and a trace of feldspar. Based on chemical, isotopic, and simple salt weight percent data, dissolution of gypsum is the major source of salinity in southern Juab Valley water. Using the chemical and isotopic data as input , a mass balance computer software program (NETPATH) helped to determine that the gypsum is derived from the Arapien Shale . NETPATH and the potentiometric surface map helped to define the main ground-water flow path as southwest across southern Juab Valley, from Chicken Creek in the San Pitch Mountains on the east side of the valley toward Chick Creek Reservoir in the southwest part of the valley.

Thesis (M.Sc.(Geology)) -- University of Limpopo, 2022 / The Limpopo Province is largely underlain by crystalline basement rocks, which are characterised by low porosity and permeability. The climate in this province is arid to semi-arid, with scarce surface water for domestic and industrial use. As a result, groundwater is the prime source of fresh water supply for various uses. The complex geology, the impacts of climate change and man-made interactions with groundwater and surface water are the main threat to the availability of a sustainable source of fresh water in the province. In addition, despite substantial research efforts conducted by academic institutions and government organisations, there is still a gap in understanding quantitatively the dynamics of the hydrological systems in large parts of the Limpopo Province. The present study is therefore focused on the investigation of hydrological stresses that are applied to groundwater and surface water in one of the catchments situated in the Limpopo Province. In this study, a three-dimensional steady-state numerical model of groundwater flow was carried out at Mogalakwena Subcatchment, which is situated in the western sector of the Limpopo Province. The area is situated approximately 40 km northwest of Mokopane and 50 km west of Polokwane town. The research aims to understand the dynamics of the exchange between surface water and groundwater, and to assess the influences of these processes on the sustainability of water supply in the area. Hydrologically, the area falls within the boundaries of the Mogalakwena River Catchment, which forms part of the Limpopo River Basin. Previous studies suggest that there is a continuous decline in groundwater levels in the study area due to extensive use of groundwater for mining, irrigation, and domestic purposes. Furthermore, continued climate changes have altered the rainfall events during the last couple of decades, which consequently had an impact on groundwater recharge, quality, and availability. In addition, the complex geology of the area has an impact on the aquifers’ productivity resulting in variability in borehole yields throughout the study area. To achieve the aims of the research project, a three-dimensional steady-state numerical model of groundwater flow was implemented using MODFLOW NWT and ModelMuse v graphical user interface. The model domain covers an area of 5896 sq. km and was discretised with a grid cell size of 200 m by 200 m. The MODFLOW Packages used include DIS, UPW, RCH, EVT, WEL, GHB, RIV and UZF as well as the ZONEBUDGET. The conceptual model of groundwater flow consists of two layers, and it was developed based on drillhole logs, hydrochemical data, environmental isotopes, geological, digital terrain models, and other spatial data relevant for the conceptualisation of boundary conditions and hydrological stresses. The results of the steady-state simulation of groundwater flow show that recharge contributes 99.6% of inflow, followed by river leakage (0.36%) and GHB (0.08%). Among the outflow components, surface runoff takes the lion’s share (83.3%), followed by evapotranspiration (16.6%) and river leakage 0.02%. The zone budget was implemented to evaluate the interaction between surface water and groundwater by quantifying the amount of water that flows from one zone to the other. This was achieved by assigning zone numbers to the objects that represent boundary conditions (e.g., aquifer, river and dam). Zone 1, 2 and 3 were assigned to the aquifer, river and dam, respectively. The results indicate that the rivers gain more water than they supply to the aquifer. Similarly, the Glen Alpine Dam gain more water from the aquifer than it supplies to the aquifer. This implies that the interaction between surface water bodies such as rivers and dams have a significant impact on the aquifer, which consequently partly contributed to the shortage of water in the area. A predictive analysis of the aquifer’s response to an increase in abstraction rate, evapotranspiration rate and a decrease in recharge was carried out to investigate the future fate of water availability in the study area. The results suggest that as recharge decreases, the river inflow slightly increases to compensate for the declining water level due to the river stage exceeding the piezometric surface. In addition, the decrease in recharge rate is accompanied by a slight decrease in both surface runoff and evapotranspiration rate. Thus, a decline in recharge causes a significant drop in piezometric surface relative to the evapotranspiration extinction depth, which ultimately decreases the rate of evapotranspiration. Similarly, a decrease in recharge rate lowers the depth of the water level below the river stage, which consequently triggers water vi exchange from Mogalakwena River to the aquifer. In general, the water balance shows that as recharge decreases by 20% or more, the outflows exceed the inflows resulting in a continuous drop in water level, which may ultimately risk the availability of groundwater in the area. / Council for Geoscience (CGs)

This report is a comparative study of ground water and surface water quality protection of a developing country India and a developed country Sweden. It covers the basic water policies, laws, rules, regulations and human right to water provisions in both the countries. The main aim of this report is to compare water quality approaches in India and Sweden and find out the best possible practices in each country and assess the need &amp; feasibility of their application in the other. It describes the present water laws in both the countries and discusses about the present scenario of ground water and surface water quality, problems in ground water and surface water and how to deal with the problems in an efficient and sustainable way. It includes role of EU Water Framework Directive (EU WFD) in water quality protection in Sweden. Some interviews with stakeholders who are working in the water sector in Sweden are also included here. The main focus of this report is to analyse comparatively the present situation of water quality protection approaches and make recommendation for improvement of water quality. It focuses on “What can a developing country like India can learn from a developed country like Sweden for water quality protection?” and “Which things Sweden can adopt from India for water quality protection?” In this study India is found in worse environmental condition than Sweden. Indian ground water and surface water is more polluted than Swedish surface and ground water. Sweden is in much better condition than India and this country has more environmental concern too. In India, the basic reason for deterioration of water quality is lack of environment friendly attitude among the public, religious activities in water, corruption, loss of traditional methods of water conservation and protection, useless and unnecessary westernisation etc. In Sweden the basic cause of water quality deterioration is eutrophication in lakes, climate change, morphological changes, presence of metals and connectivity changes due to construction works, acidification etc. Sweden is an advanced country having the foresight for environmental concerns. They are doing research for betterment of water quality. India can learn some technological advancement and proper implementation of community participation in order to establish decentralised wastewater treatment plants and beneficial production and monitoring of energy resources from wastewater. Maintenance of online database for water is also a good thing to learn from Sweden.