eChapters

Abstract

A study on colloids in groundwater and its relationship with the geochemical parameters is reasonably essential because of its facilitating nature to transport radionuclides in groundwater. Colloid sampling has been carried out in the coastal aquifers of southeast coast of India. Two different bore wells were selected based on the distance from the coast to collect groundwater samples. On the basis of the result achieved from this study, a reliable representation is emerging. The values of pH and EC are governed by the different size fraction of colloids. In this study, the relation between different size fractions of groundwater colloids and its pH, TDS and EC were carried out. These parameters were analyzed in the lab and its influence with four fractions of colloid like 1.2, 0.8, 0.45 and 0.22 µm have been discovered by smooth scatter plot. The accumulation of particles weighting by normal weighing instrument. There is an higher accumulation of particles found in Kalpakkam than Anupuram in all the size fractions. For separation of particles high frequency pressure was used by ultrasonic cleaner had been carried out. This method is very simple and more reasonable than any other methods.

Abstract

In Gadilam river basin, groundwater is found in both hard rock and sedimentary terrain and is the most important source of rural/urban drinking water supply. Gadilam river basin has gained its importance due to the presence of Neyveli Lignite open cast mine (NLC), group of industrial estate (SIPCOT), extensive depressurization of Cuddalore aquifer and boreholes of New Veeranam Scheme (NVS) in the downstream of the basin. A total of 178 water samples were collected in four different seasons at various lithologies. The collected samples were analyzed for various physico-chemical parameters using standard procedures. Geochemical indicators of groundwater were used to identify the chemical processes that control hydrogeochemsitry. Interpretation of hydrogeochemical data suggests that leaching of ions followed by weathering and anthropogenic impact controls the chemistry of the groundwater. Isotopic study reveals that recharge from meteoric source in sedimentary terrain and rock water interaction with significant evaporation prevails in hard rock region. This thorough understanding helps us to make judicial usage and to maintain the quality of this commodity.

Abstract

The development and management of fresh groundwater resources in coastal aquifers are seriously constrained by the impact of seawater intrusion. The coastal aquifers are fragile and this situation becomes more intense like that of the coastal Cuddalore region. The geochemical signature of groundwater of Cuddalore coast was studied for Pre Monsoon, Southwest, North east and Post Monsoon seasons by collecting total of 64 groundwater samples in each season. The collected samples from were analysed for physical parameters, such as electrical conductivity (EC), pH and major ion concentrations, such as Ca, Mg, Na, K, Cl, HCO₃, PO₄ and SO₄. Interpretation of analytical data shows the predominance of  Na–Cl type   in PRM and Ca- Mg-Cl type  is the dominant facies during POM. The Chaddas evaluation diagram shows that the hydrogeochemical evaluation plot for PRM samples fall in  Na-Cl type. The ratios of Na/Cl and Cl/HCO₃ is also enumerated the fact that the most of the samples from PRM and few samples from other seasons also indicates dominance of salt water intrusion.

Introduction

In India there are about 200 distillery having installed capacity 1555.5 million liters per annum out of which 50% are of 30 KL/ per day capacity about 50% of remaining distillery are of 45 to 60 KL/ per day capacity there are few distilleries which having go 120 KL/ per day capacity. Distillery waste is one of the major industrial waste having high organic and inorganic constituents in the recent past the treatment and disposal of distillery waste has become a subject of debate of each and every forum.

Introduction

Reservoirs constitute the prime inland fishery resource in the country by virtue of their numerous production potential. These man-made ecosystems offer enough scope for stock manipulation through ecological maneuvering, paving the way for production hikes at a relatively low-capital investment. Unlike the aquaculture systems, where the development is capital intensive, a reservoir fishery development is labour productive and ensures employment for some of the weakest sections of our society.

Abstract

Aquifers are usually composed of permeable layers that can ways a considerable amount of groundwater. Usually, aquifer units are correlated through the concept of lithostratigraphy. For low-permeable aquifers, it is difficult to define the spatial distribution of hydrogeological units, and this study attempts to use geochemical methods to identify the groundwater flow paths in an area of Southeast coast of Tamil Nadu, India. Multiple geochemical analyses, including groundwater chemistry; stable isotopic compositions of d¹⁸O and 8D contents were performed.  Spatial distribution of d¹⁸O, dD, Cl-/HCO-₃ show that northeastern part of the study area seriously affected by seawater intrusion. The highly permeable aquifers at the east coastal region are characterized by high hydraulic conductivity as compared with other regions of the study area. Hydrogeochemical characteristics based on bivariate diagrams of major and minor ions show that changes in the chemical composition of groundwater are mainly controlled by the salinization process followed by cation-exchange reactions.

Abstract

Dissolved Organic Carbon (DOC) consisting of water soluble organic molecules and by products of organic decomposition and chemical degradation processes, constitutes a critical link in carbon and nutrient cycles. The quality, or chemical and physical character, of DOC affects the degree to which it is transformed by biological and chemical processes. The significance of DOC was studied in layered coastal aquifers of the Pondicherry region during four different seasons. Pondicherry region has varied geological set up ranging from Cretaceous to Recent formations. A total of 52 groundwater samples were collected from various aquifers like Alluvium, Tertiary(Upper Cuddalore, Lower Cuddalore) and Cretaceous for two different seasons of pre- monsoon(PRM), and post-monsoon (POM). The samples were analyzed for major ions and DOC. The range of DOC in the study area is 0-14 mg/l. Very high DOC concentrations were measured during PRM in the samples from Alluvium and Lower Cuddalore Formation. The samples of these formations were compared with pH, Ionic strength, log pCO₂ and carbonate minerals concentration. The alluvial aquifer shows that pH governed dissolution along the coastal tracts and in Upper Cuddalore formation it’s based on interaction between aquifer matrix and groundwater.

Abstract

Groundwater is most favored as a source of drinking water in all over world. It is often thought to be cleaner and easier to treat when compared with surface water and as a result, many wells have been sunk. Uranium and other radionuclides in water can lead to health problems if present in higher concentrations. In order to study the behavior and to understand the influence of lithology in groundwater of Madurai district, a study was conducted by collecting a total of 216 samples of different seasons (Premonsoon, South west monsoon, Northeast monsoon and Post monsoon) with respect to lithology and the number of samples was depending upon their spatial coverage in the study area. The groundwater samples were analysed for U, Ca²⁺, Mg²⁺, Na⁺, K⁺, HCO₃^-, Cl^-, SO₄^2-, PO₄^3-, NO₃^-, F^-, H₄SiO₄, pH, EC, TDS. It was identified that the higher concentration of Uranium (156 ppb) were noted in the northern part of the study area. They are chiefly restricted to the Granitic terrain and nearby Charnockitic regions. The weathering process induces the release of higher U ions from the granitic terrain and the evaporated recharge water from the tank /reservoir  also induces the release of U ions from the rock matrix, it may also be due to fertilizer enriched agricultural return flows. The key source for all these processes and hydrogeochemical processes is identified to be lithology which inturn controls all the other processes in the study area.

Introduction

A disaster is the result of an immediate situation or the result of a long, set process, which disrupts normal human life in its established social, traditional and economic system. This is due to the destruction of environment which is caused by extraordinary natural destructive phenomena or human-induced hazards resulting in human hardship and suffering beyond recovery unless external aid is brought in.

Introduction

Large scale exploitation of groundwater using modern deep well boring technology and powerful pumps is the order of the day in India and elsewhere. Increase in agriculture area and year around cultivation of water intensive crops, frequently failing monsoons (Fig.5.1) all have led to drying up of surface water and increased dependence on groundwater.

Thus, given the scenario of over exploitation of the available groundwater, it is essential that proper storage and management of available groundwater resources be identified.

Introduction

The need for water for human consumption and the industry keeps spiraling up in the cities in the wake of rural diaspora and urban sprawl. Groundwater is exploited at an unsustainable rate leading to depletion of aquifers. Worse still is the intrusion of salt water from adjoining coast into the aquifers leading to total wastage of remaining water.

In the last chapter, we have broadly introduced the concept of tracer hydrology and also the concepts of isotopes as tracers, their characteristics and measurement techniques. In this chapter let us see the basis of application of each group of isotope tracers, injected and environmental.

What are the different groups of isotope tracers used in hydrology and how are they classified?

Abstract

Amongst all types of major land-use change, extending irrigated agriculture using a surface-water source has the greatest influence on groundwater – both significantly increasing recharge and changing water quality as excess irrigation water infiltrates into shallow aquifers. Hence, in order to understand the impact of the landuse on the groundwater system the study has been aimed to understand the process by adopting geophysical, geochemical and microbial analysis of groundwater samples. The study has been conducted in Chidambaram taluk, with a total area of 92.51Sq.km. A total of 39 groundwater samples were collected for the analysis of major cation and anion along with the microbial analysis, like Total Coliform, Total Viable Counts, Fecal coliforms, Vibrio cholera and Total Streptococci. The geochemical studies reveal that there is no correlation between these parameters and the microbial population. The migration of the water from the elevated regions (urban region) is witnessed and the concentration of the microbial population is higher in these regions except in the southern region which has impermeable clay and this arrest the movement of water.

Abstract

Geochemical processes occurring within the groundwater and reactions with aquifer minerals have a profound effect on water quality. Hydrogeochemical composition of groundwater can also be indicative of its origin and history of passage through underground materials which water has been in contact. Assessing groundwater quality and developing strategies to protect aquifers from contamination are necessary aspects for proper planning and designing water resources. Anthropogenic activities like explosion of population, industrial growth, inputs of fertilizer, pesticides, and irrigation has been a crucial factor for determining the quality of groundwater. In this scenario, 43 groundwater samples were collected from the Dindigul district of Tamilnadu, a Hard rock terrain. The samples wereanalyzed for major cations and anions along with heavy metals to derive the different quality parameters and to obtain the pollution indices of different samples. This study focuses to find out the spatial relationship between the analyzed fluoride concentration in groundwater and pollution indices derived from the heavy metal concentration in the groundwater of the study area and their variation with respect to season.

Water is a social requirement. Society now become aware about it’s dependence upon water and hence realized the importance of water in sustaining not only the development but also life. Water: too little, too much, too dirty; is general scenario in the world. But with increase in population water become limiting resource and is becoming scarcer and scarcer day by day. As water become scarcer commodity, the users (stakeholders) become more conscious regarding their share in water and ultimately this situation may lead to water conflicts. Earlier water related problems were generally tackled by hydro-engineers, but now in present climate changed scenario these problems go beyond the hydraulics and hydrology. Now a days politicians, ecologists, Non Government Organizations (NGOs), the media and the stakeholders etc are playing a crucial role in decision making in respect to water management issues. Now water projects are designed in reference to social context (Social context means cultural, economic, political, sociological, legal and other such aspects). When social factors are taken into consideration while tackling the water problems, it could not possible to satisfy all involved. Thus it is required to agree upon a compromise solution acceptable to all. Over recent few decades, information and communication technology (ICT) flourishes with great advances. It provides the ways to search for compromise solutions. In this chapter information, hydroinformatics, evolution of hydroinformatics and role of internet in hydroinformatics are discussed.

The range of isotope applications in surface water hydrology is not as wide as in groundwater hydrology as the surface waters are more easily amenable to conventional hydrological methods. Following are the areas in which isotopes have a significant role in either improving the accuracy of measurements or in providing additional information, which is otherwise not easily available.

After precipitation, run-off and surface water storage in lakes and man-made reservoirs, the next steps in the hydrological cycle are infiltration through the unsaturated zone and groundwater dynamics in the saturated zone. Well-established applications of isotopes in groundwater hydrology are

Abstract

The anomalies observed in the reverine systems have been demonstrated to be the potential tool in deciphering the tectonically active zones. Such various drainage anomalies viz: radial drainages, anomalous compressed meanders, eyed drainage and the youthful floodplains observed in Annamali – Palani - Varushanad hill ranges of the Western Ghats of Tamil Nadu show that the N-S and NE-SW trending faults are tectonically active in the recent years.

Abstract

The Remote Sensing and the followed up field based investigations show that the Tamil Nadu coast, India, is facing series of geoenvironmental problems due to tectonic movements and morphodynamic processes. Such problems pose a challenge to the engineering geologists. The paper discusses such challenging engineering geological problems and plausible remedial measures.

In this era of computer, mathematical models become integral part of hydrologic studies due to advancement in soft technology. But question always arises as ‘Why should modeling?’ It was well expressed by Rosenblueth and Wiener (1945) as

No substantial part of the universe is so simple that it can be grasped and controlled without abstraction. Abstraction consists in replacing the parts of the universe under consideration by a model of similar but simpler structure. Models, formal or intellectual on the one hand, or material on the other are thus a central necessity of scientific procedure.