Robert G. Maliva

• Schlumberger Limited

Brackish water reverse osmosis (BWRO) desalination of groundwater is believed to be a sustainable method of providing municipal utilities with a high-quality supply in regions where freshwater sources are stressed and not sustainable. A key aspect of water management is the ability to evaluate an aquifer containing brackish water to ascertain futur...

The successful management of a brackish-water reverse osmosis (BWRO) desalination facility depends on understanding future expected water-quality changes and how these changes may affect the operational reliability of the water treatment plant. Because most production aquifers that supply feed water for BWRO facilities are leaky to some extent, lon...

Brackish-water reverse osmosis (BWRO) desalination facilities are designed to treat feedwater within a fixed range in salinity. If the salinity and ion concentrations of the feedwater rises above the maximum design concentrations, then the plant may ultimately fail. BWRO plants typically use groundwater as a feedwater source. Prior to the process d...

Florida has been described as ‘ground zero’ for climate change in the United States with coastal communities vulnerable to sea-level rise and water supplies under threat from saline-water intrusion, changes in precipitation amounts and patterns, and temperature-driven increases in demands. Water utilities and regional suppliers are responsible for...

Use of hydraulic fracturing in the completion of oil and gas wells in tight geologic formations has revolutionized the petroleum industry by increasing production and the quantity of available reserves. The practice has been controversial because of real and perceived environmental impacts, particularly groundwater contamination. A detailed scienti...

Surface spreading is the simplest, oldest, and mostly widely used method of managed aquifer recharge (MAR). Stormwater, river water, treated wastewater, and other waters are either applied to a land surface or locally impounded in infiltration basins, reservoirs, or modified stream channels. Typically, the water table is located below land surface,...

Clogging is a local reduction in permeability caused by the filling or obstruction of pores and pore throats. Clogging can be the result of physical, chemical, or biological processes, or some combination of the three. The principle loci of clogging in managed aquifer recharge (MAR) systems is at or just below the infiltration surface (e.g., basin...

Pretreatment of water prior to managed aquifer recharge (MAR) is often necessary to reduce clogging rates, prevent adverse geochemical reactions, and meet health-based regulatory requirements. Where MAR is being used as a natural water treatment technology, pretreatment can be an important element of a multiple-barrier approach to protecting public...

Groundwater over time approaches chemical equilibrium with respect to the reactive minerals present in an aquifer. Aquifers may contain some minerals that are essentially unreactive in that their dissolution and precipitation rates are exceedingly slow under the temperature, pressure, and chemical conditions that occur in most near-surface groundwa...

Unmanaged and unintentional recharge is recharge incidental to other human activities. Unmanaged and unintentional urban recharge includes leakage from water and wastewater mains, discharges from on-site sewage systems, recharge from stormwater management infrastructure, and return flows from the irrigation of parks, lawns, and other vegetated area...

The term soil-aquifer treatment (SAT) is used to refer to both high-rate domestic wastewater aquifer recharge and recovery (ARR) systems and, more broadly, the process of natural contaminant attenuation that occurs as applied water passes through the vadose zone. As the concept was originally defined, treated wastewater is recharged using infiltrat...

Managed aquifer recharge (MAR) using wells includes aquifer storage and recovery (ASR; local storage of water by injection and recovery using often the same well), aquifer recharge using wells (injection intended to increase aquifer water levels or improve water quality), and vadose or dry wells. ASR systems commonly store freshwater in brackish or...

The design, operation, and evaluation of managed aquifer recharge (MAR) and other anthropogenic aquifer recharge (AAR) systems should be based on a sound understanding of hydrogeological principles, local hydrogeological conditions, and how hydrogeology impacts system performance. A review of the historical performance of MAR systems revealed that...

Both operational and experimental results demonstrate that the concentrations of pathogens and some chemical contaminants decrease during infiltration, percolation, and saturated-zone flow and residence. The improvement in water quality may be either unplanned (incidental) or intentional. The intentional use of natural contaminant attenuation proce...

The vadose zone consists of the soil or rock located between land surface and the regional water table and forms the interface between a surficial hydrological system and its underlying aquifer. Vadose zone processes control the rate of recharge in surface-spearding managed aquifer recharge (MAR) systems and increases in importance as the depth to...

Managed aquifer recharge (MAR) is used to either store or treat water (or a both). MAR systems that have a primary treatment function include aquifer storage transfer and recovery (ASTR), aquifer recharge and recovery (ARR), dune filtration, soil-aquifer treatment, and riverbank filtration. ASTR systems recharge using wells and recover using separa...

Infiltration basins are a widely used surface-spreading method for infiltrating stormwater, surface water, and reclaimed water. A variety of other types of surface-spreading methods are also used for managed aquifer recharge, which vary depending upon whether they occur in an unmodified channel, modified channel, or on off-channel land surfaces (e....

The composition of recharge water evolves as it passes through the unsaturated zone and enters and flows through an aquifer. Infiltrated and injected waters interact with aquifer minerals and organic matter, and mix and react with native groundwater. Geochemical processes during and after aquifer recharge can either improve or cause a deterioration...

Vadose zone hydraulic properties impact the performance of surface-spreading MAR systems by controlling the rate of flow of water from land surface to the water table. Single- or double-ring or basin (pilot) infiltration tests are typically performed to estimate infiltration rates. Vadose zone hydraulic properties obtained from infiltration tests a...

Hydrogeological and hydrochemical data collection programs for managed aquifer recharge (MAR) systems need to be designed to meet project-specific information requirements, which may include information on aquifer hydraulics and transport parameters, vadose zone properties (e.g., infiltration rates), aquifer mineraology, and native groundwater and...

Surface infiltration systems are generally preferred for managed aquifer recharge (MAR) because they offer the best opportunity for clogging control and water quality improvements through contaminant attenuation processes in the vadose zone. Vadose zone infiltration systems include infiltration trenches, galleries, shafts, pits, and dry wells. Vado...

Adding additional freshwater to aquifers that are depleted is usually inherently beneficial. However, it is important to have a quantitative understanding of the magnitude, duration, and location of actual hydrological benefits of proposed and operational managed aquifer recharge (MAR) systems. MAR and unmanaged and unintentional recharge need to b...

Riverbank filtration (RBF), which is also referred to as bank filtration, induced infiltration, and induced recharge, is a very old technology for treating surface water. Surface water is indirectly drawn from rivers or lakes using wells, galleries, or collectors constructed on adjacent land. RBF systems take advantage of the natural filtration and...

Under predevelopment conditions, much of rainwater stayed in the area where it fell, either recharging the underlying shallow aquifer or slowly returning to the atmosphere via evapotranspiration. Land development activities increase the imperviousness of land surfaces, decreasing infiltration and increasing runoff. Traditional stormwater management...

Groundwater banking broadly refers to the large-scale storage of water in aquifers for later use. The storage may be either seasonal or interannual. Interannual storage can provide a buffer against droughts and other interruptions in water supplies (e.g., disruptions of desalination facilities). Groundwater banking is performed by direct recharge u...

MAR planning and implementation start with identification of project goals and success criteria. A feasibility assessment is then performed to determine whether MAR is technically and economically feasible in the proposed project areas. Feasibility assessments involve both a review of existing data and regulatory requirements and constraints (deskt...

Saline-water intrusion is the induced flow of saline or brackish water into freshwater aquifers. In coastal areas, horizontal saline-water intrusion involves the landward migration of the roughly wedge-shaped interface between saline and fresh groundwater. Vertical saline-water intrusion (referred to as up-coning) is the upward migration of more sa...

Aquifer storage and recovery (ASR) is a valuable tool for managing variations in the supply and demand of freshwater, but system performance is highly dependent upon system‐specific hydrogeological conditions including the salinity of the storage‐zone native groundwater. ASR systems using storage zones containing saline (> 10,000 mg/L of total diss...

Previous geochemical, petrological, and sedimentological investigations of the Middle Eocene Avon Park Formation (Middle Eocene) of Florida suggest that dolomitization occurred in the Eocene from normal to hypersaline seawater. Reflux of penesaline water (i.e., seawater evaporatively concentrated below evaporite mineral precipitation) is the most l...

Southern Florida is underlain by rocks and sediments that naturally contain radioactive isotopes. The primary origin of the radioactive isotopes is Miocene-aged phosphate deposits that can be enriched in uranium-238 and its daughter isotopes. Nodular phosphate containing radionuclides from the Miocene has been reworked into younger formations and i...

Groundwater resources are under stress in many areas from increased extractions resulting from population growth, economic development, climate change, and other factors. Aquifer overdraft results in declining aquifer water levels and often deteriorating water quality. One element of the solution to aquifer overdraft is increasing aquifer recharge....

Irrigation with wastewater has been practiced for millennia in areas facing water scarcity because it does not require water of the highest quality and wastewater contains nutrients needed for crops. Wastewater is also recycled for industrial uses and there is increasing interest in its use to augment potable water supplies. Some areas facing water...

The modal composition of sandstones has long been used as a tool for palaeotectonic and palaeoenvironmental analyses. Herein it is demonstrated that caution must be used when beach sand composition is utilized to assess tectonic provenances at both the local and continental scales. The occurrence of quartz arenites and compositionally mature sands...

Horizontal and slant wells are being investigated as a means of obtaining feed water for seawater reverse osmosis (SWRO) desalination plants. These well types have been touted to produce higher quality seawater that will reduce the rate of membrane biofouling by removing algae, bacteria, transparent exopolymer particles, and other fractions of natu...

Florida geologic units and soils contain a wide range in concentrations of naturally-occurring arsenic. The average range of bulk rock concentrations is 1 to 13.1 mg/kg with concentrations in accessary minerals being over 1000 mg/kg. Florida soils contain natural arsenic concentrations which can exceed 10 mg/kg in some circumstances, with organic-r...

Florida geologic units and soils contain a wide range in concentrations of naturally-occurring arsenic. The average range of bulk rock concentrations is 1 to 13.1 mg/kg with concentrations in accessary minerals being over 1,000 mg/kg. Soils contain natural arsenic concentrations of between 0.18 and 2.06 mg/kg with organic-rich soils having the high...

Management of reclaimed water is an ever increasing challenge on barrier islands and coastal communities because of increasing populations (and associated reclaimed water flows), limited and usually prohibitively expensive land availability for land application methods, and environmental concerns over marine and bay discharges. Destin Water Users,...

Managed Aquifer Recharge (MAR) systems can be used within the context of integrated water management to create solutions to multiple objectives. Southwestern Florida is faced with severe environmental problems associated with the wet season discharge of excessive quantities of surface water containing high concentrations of nutrients into the Caloo...

Seawater reverse osmosis (SWRO) desalination has some environmental impacts associated with the construction and operation of intake systems and the disposal of concentrate. The primary impact of conventional open-ocean intake systems is the impingement and entrainment of marine organisms. These impacts can be minimized by locating the intake in a...

Past geomorphological models assume that erosion of sediments from old mountain belts occurred at a relatively constant rate based on comparatively uniform isostatic adjustment caused by unloading. Late Miocene strata of the south-eastern United States provide an example of pulsed tectonism resulting in a surge in siliciclastic sediment production...

Slug tests are a commonly used method to determine the hydraulic conductivity of strata near a borehole. The tests involve recording the water level (pressure) response in a well to an instantaneous increase or lowering of water level. Slug tests have the advantage of being quick, inexpensive to perform, and do not generate water that requires disp...

Data on aquifer storage properties (storativity and specific yield) are required for transient groundwater models. Storativity is usually determined from aquifer pumping tests using the Theis method or variations thereof. Quantification of specific yield is much more challenging because of the long time required (especially in fine-grained sediment...

Karst aquifer systems are characterized by often extreme heterogeneity as flow is dominated by secondary porosity, which includes fractures and solution conduits of multiple scales. Karst aquifers cannot be fully characterized using conventional hydrogeological methods alone, such as potentiometric surface mapping and well pump testing. A basic lim...

Aquifer pumping tests are an integral component of aquifer characterization because they provide quantitative data on large-scale aquifer hydraulic properties such as aquifer transmissivity, storativity, and the vertical hydraulic conductivity (leakance) of confining strata. Aquifer performance tests (APTs), also referred to as aquifer pumping test...

Borehole geophysical logging is a fundamental element of aquifer characterization because it can provide essentially continuous in situ measurements of the petrophysical properties, lithology, location and types of secondary porosity, and pore-water quality (salinity) of the logged strata.

Surface and airborne geophysical methods can be a valuable element of aquifer characterization programs because they typically are less expensive and can be performed quicker than methods that require the drilling of boreholes, which allow a larger number of measurements and thus greater spatial coverage.

Groundwater tracer tests involve the use of existing or introduced variations in water chemistry or properties to obtain information about groundwater flow rates and directions, aquifer hydraulic and transport properties, and fluid–rock interactions. Tracer tests vary greatly in their objectives and complexity. Natural or existing anthropogenic var...

A wide variety of methods have been proposed or applied to groundwater investigations that are not yet widely utilized either because of limited applications, costs, or perhaps lack of widespread knowledge of their value and limitations. This chapter is a somewhat disjointed review of some specialized aquifer characterization techniques that did no...

Hydraulic conductivity is directly measured using Darcy’s law-based methods that induce flow through a formation or sample. Indirect measures predict hydraulic conductivity from other sediment or rock properties. Methods are reviewed for obtaining profiles of permeability (hydraulic conductivity) from borehole geophysical logs, which include use of...

Aquifer characterization is broadly defined as processes by which the three-dimensional structure, hydraulic and transport properties, and chemistry of aquifers are evaluated. Aquifer characterization provides the foundation for groundwater modeling, which is ubiquitously used to evaluate sedimentary aquifers. Detailed aquifer characterization is p...

The three-dimensional distribution of bodies of rock and sediments with different sedimentological properties and associated hydraulic properties is controlled to varying degrees by the depositional history of the strata of interest. Primary (depositional) variations in sediment textures and fabrics are modified by diagenetic processes, such as com...

Carbonate aquifers consist of rocks composed mainly of the minerals calcite and dolomite. Carbonate minerals are generally much more chemically reactive under near surface geochemical conditions and thus undergo a much greater degree of chemical and physical alteration (diagenesis) than siliciclastic deposits. The textures and fabrics of carbonate...

Aquifer characterization programs need to be designed to provide the specific data required for groundwater resources projects, which commonly involves the development of conceptual and numerical groundwater models. Available characterization techniques are compiled in terms of the type of information provided and scale (investigated volume or radi...

Well construction and drilling techniques are reviewed focusing on the appropriateness of different methods for various aquifer characterization scenarios. The drilling method and well construction selected for an aquifer characterization program should be based on consideration of the type of testing to be performed, borehole conditions required f...

Small-volume methods are, in essence, point measurements of the petrophysical and hydraulic properties and lithology of aquifer and confining strata. Small-volume methods have the advantage that they are often relatively simple and inexpensive to perform, but have the limitation that the results of individual analyses are usually not representative...

Fractured sedimentary rock contains two domains, the fractures and adjoining rock matrix. Fractures often provide most of the aquifer transmissivity, whereas the bulk of water and solute storage may occur in the matrix. The concentration of flow in fractures, which constitutes a very minor part of the total volume of the strata, results in greater...

Aquifer characterization programs are usually performed with the objective of obtaining the data required to develop numerical groundwater models. Groundwater modeling starts with the development of a conceptual model, which is followed by the selection of a modeling code and model discretization. Initial values for the hydraulic and transport prop...

Siliciclastic aquifers are composed of sediment and rock that are dominated by silicate minerals, particularly quartz, feldspar, and clays. Siliciclastic aquifer properties are controlled by the grain size, sorting, and diagenesis of the sediments. Well-sorted sand and gravel facies deposited by flowing water and air tend to have the highest hydrau...

Direct-push technology (DPT) is a widely adopted, low-cost method for collecting groundwater samples from unconsolidated or semi-consolidated shallow aquifers without a need for permanent monitoring wells. DPT methods are also used to install permanent small-diameter monitoring wells. DPT has the great advantage of generating minimal investigation-...

Geostatistical analysis techniques are used to predict the values of parameters between data points. Geostatistical methods are only valid for spatially dependent (i.e., nonrandom) data. The basic method is to first identify and quantify the spatial structure of the variables of concern and then to interpolate or estimate the values of variables fr...

Alternative water supply, storage, and treatment (AWSST) systems, which utilize aquifers to supply, store, and naturally treat water, are increasingly being implemented globally to address water scarcity and safety. The failure of some AWSST systems to meet water quality expectations was caused by conceptual model error, in which local hydrogeologi...

This book presents an overview of techniques that are available to characterize sedimentary aquifers. Groundwater flow and solute transport are strongly affected by aquifer heterogeneity. Improved aquifer characterization can allow for a better conceptual understanding of aquifer systems, which can lead to more accurate groundwater models and succe...

Religious and cultural values related to water use and management are important motivation for many people of the world. Although much has been written related to water management and use in Islam, fewer authors have attempted to evaluate water management through the lens of other religions. The common thread of monotheism, specifically worship of...

The performance of managed aquifer recharge (MAR) systems is highly dependent upon local hydrogeology, which controls the movement and mixing of stored water and fluid-rock interactions, which can impact recharged water quality. The leading edge of MAR technology is the integration of data obtained using conventional and advanced aquifer characteri...

Of the various subsurface intake systems available for use, gallery intake systems have the greatest potential to provide the feed water requirements of very large-capacity seawater reverse osmosis (SWRO) systems because of their scalability and flexibility as far as hydrogeological constraints. A beach gallery system is constructed beneath the int...

Over the past several decades, many improvements have been made in the design and operation of seawater reverse osmosis desalination systems (SWRO), including the intakes that provide feed water. The invention of the velocity-cap offshore intake system reduced the entrainment of fish due to their sensing of horizontal flow versus vertical flow. Use...

Depletion of water supplies for potable and irrigation use is a major problem in the rural wadi valleys of Saudi Arabia and other areas of the Middle East and North Africa. An economic analysis of supplying these villages with either desalinated seawater or treated wastewater conveyed via a managed aquifer recharge (MAR) system was conducted. In ma...

Wadi channel recharge to the underlying alluvial aquifer is naturally limited by the flashy nature of flood events, evapotranspiration losses of water from the vadose zone, and aquifer heterogeneity, particularly low vertical hydraulic conductivity. Anthropogenic lowering of the water table in many wadi aquifers has also reduced the potential recha...

Managed aquifer recharge (MAR) will play an increasingly important role in solving water scarcity. The performance of MAR systems depends primarily upon local hydrogeology. Greatest opportunities for improvement in the implementation of MAR systems lie in the targeted application of conventional and advanced technologies to improve aquifer characte...

All aquifers have some degrees of heterogeneity, which if extreme, can adversely affect the performance of ASR systems. There are many types of aquifer heterogeneity that may be encountered in the field. Two of them are considered here: non-uniform distribution of transmissivity in the storage zone and dual porosity. As indicated by the flowmeter l...

Managed aquifer recharge (MAR) technologies can provide a variety of water resources management benefits by increasing the volume of stored water and improving water quality through natural aquifer treatment processes. Implementation of MAR is often hampered by the absence of a clear economic case for the investment to construct and operate the sys...

Brackish groundwater sources suitable for desalination are often present in regions where freshwater is scarce. Brackish groundwater requires less energy and pretreatment to desalinate than seawater, making it a water source worth considering in certain situations.

Groundwater banking is the use of aquifers to store water to balance seasonal or longer-term variations in supply and demand. The large storage capacity provided by aquifers can be a valuable tool for conjunctive use of surface water and groundwater as well as other elements of integrated water resources management. Successful groundwater banking r...

Desalination of seawater using the reverse osmosis process can be made less costly by the use of subsurface intake systems. Use of conventional open-ocean intakes requires the addition of a number of pretreatment processes to protect the primary RO process. Despite using the best designs possible for the pretreatment, seawater RO membranes tend to...

Economical and environmentally sound disposal of desalination concentrate can be the critical feasibility issue for inland desalination projects where a surface water outfall is not possible. Deep well injection can be a viable means to permanently remove concentrate and other liquid wastes from the biosphere. However, deep well injection requires...

The bulk of this book is dedicated to the technical issues and methods used to assess, manage, and develop water resources in arid and semiarid lands, with a strong focus on groundwater resources. Sound science (i.e., understanding of hydrogeologic systems in questions and their response to water use) should provide a framework upon which water man...

Coastal areas in arid and semiarid lands face additional groundwater management challenges from salinization compared to more inland areas. Saline–water intrusion, in particular, is a major threat to coastal aquifers. Saline–water intrusion occurs in areas where the rate of groundwater extraction significantly exceeds the rate recharge. Over extrac...

Both the vadose and phreatic zones are active chemical, physical, and biological environments. The concentrations of pathogens and chemical contaminants tend to be reduced as water infiltrates into the soil, percolates to the water table, and flows through aquifers. The contaminant attenuation processes include filtration, sorption, precipitation,...

Since the 1980s, Integrated Water Resources Management (IWRM) has become the most often espoused paradigm for the management of water resources. The most widely used definition of IWRM is that of the Global Water Partnership. IRWM is a process which promotes the coordinated development and management of water, land, and related resources, in order...

Water management challenges increase greatly when a resource is shared between different political entities. Intra-national conflicts, such as between states, can be resolved using existing national courts or legislative or political institutions, although not necessarily to the satisfaction of all parties involved. The difficulty of resolving conf...

A large part of the global population lives in arid lands which have low rainfall and often lack the water required for sustainable population and economic growth. This book presents a comprehensive description of the hydrogeology and hydrologic processes at work in arid lands. It describes the techniques that can be used to assess and manage the w...

Humans have throughout history adapted to climate change, and will out of necessity adapt to future climate change. However, compared to climatic changes in the past, the changes that are presently taking place are occurring in a world where many vast areas are densely populated and have a high water demands. Even without climate change, many areas...

The health hazards associated with wastewater are a function of concentration of contaminants in the wastewater, the duration and level of exposure, and the dose–response function for each hazard. An important issue when evaluating the potential health impacts (on humans, as well as on the general environment) of wastewater reuse is that the risk a...

Management of groundwater resources requires an understanding of the response of aquifers to groundwater withdrawals. Groundwater impact analyses are now usually performed by numerical groundwater flow and solute-transport modeling, which has become a specialized discipline. A basic knowledge of hydraulic principles is necessary for understanding t...

A quantitative understanding of aquifer water budgets is critical for effective, long-term water management. Water budgets can be directly calculated assuming that sufficient data are available. However, water budgets are now much more commonly implicitly evaluated as part of numerical surface-water and groundwater models or integrated surface-wate...

In arid and semiarid lands, desalination is one available option to meet the potable water requirements of growing populations, particularly of those countries that border the oceans and seas. Modern technology currently allows the treatment of virtually any type of water to potable standards. The critical issue is the cost, primarily the economics...

Desalination is an energy intensive technology, especially when applied to seawater. Therefore, desalination has both high costs and a very large carbon footprint when conventional energy sources are used to power the various desalination processes. A variety of renewable energy sources are available that can be applied to reduce the carbon footpri...

Measuring the rate of groundwater recharge is particularly difficult in arid and semiarid lands, which are characterized by great spatial and temporal variability in recharge. Measurements of a limited number of local (point) recharge rates over a short (several years) period does not provide data representative of basin-wide rates. Most of the rec...

The amount of research and the resulting publications on global climate changes has been truly explosive since the 1990s. The evidence is now indisputable that global climate has been warming since about 1900 and that the increase in greenhouse gases, including carbon dioxide, methane, and nitrous oxide have been a major cause of the increase. Vari...