Contaminated Groundwater Remediation– Usage of Water Harvesting under Favorable Circumstances

Open Access e-Journal

Earth Science India- www.earthscienceindia.info

Popular Issue, V (II), April, 2012, p. 1-12

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Contaminated Groundwater RemediationContaminated Groundwater RemediationContaminated Groundwater RemediationContaminated Groundwater Remediation–––– Usage of Water Usage of Water Usage of Water Usage of Water

Harvesting under Favorable CircumstancesHarvesting under Favorable CircumstancesHarvesting under Favorable CircumstancesHarvesting under Favorable Circumstances

Rolland Andrade, R. Rangarajan and D.N.V Lakshmi Devi

While the problem is enormous in the industrialized countries for which

the statistics are most readily available, in proportion to population, the

problem is undoubtedly of similar magnitude or more in most developing

countries of the world like India…………… The concept of artificial

recharge structure can be extended in pollution mitigation studies under

favorable site criterions, as it requires no addition of artificial chemicals

or processing plant.

In many countries of the world including India, groundwater constitutes the main source

of drinking water. But in recent decades, the groundwater quality has very much deteriorated

due to rapid industrialization and human mismanagement. Contaminants must often be removed

from groundwater before it reaches wells used by agriculture and municipal water supplies. The

removal of containment of pollutants is called remediation. Remediation is required when

concentrations of contaminants exceed or are expected to exceed predetermined levels for the

type of resource that is impacted. For the restoration of the contaminated aquifers, remediation

efforts are used at the contaminated source and plume to eliminate and extract the contaminants.

The remediation of contaminated aquifers is very complex, as the process of movement of

contaminants through the porous media is quite complex. The groundwater pollution

remediation can be carried out either by onsite techniques or in-situ methodologies. Even

though, in the recent times, many in-situ remediation methods have been developed, most of the

remediation works are still done on-site by pump and treat method. According to EPA

(Environmental Protection Agency) there are certain regulations published under Resource

Conservation and Recovery Act (RCRA), in which the already existing tanks or sites selected

for dumping mill tailings are to be cleaned to restore and protect groundwater resource.

Mining operation generates a large quantum of tailings otherwise termed as slimes or

leach residue, basically a mixture of fine disintegrated mineral particles and fluid, which needs

to be disposed safely without causing any environmental hazard like leaching and erosion by

wind or water. Tailings facilities consist of tailings ponds or lagoons, tailings dams and tailings

transport systems (generally pipelines). Usually a very large area is required to contain the

tailings which is man-made, and is the most critical elements of these facilities. The surface

disposal site is to be characterized for its sub-surface nature in order to understand its role in

environmental impact due to the loading of tailings. There is always possibility of contamination

of streams and groundwater system adjacent to the slimes dams which indirectly poses a

particular risk for the health of people in informal settlements where polluted stream water is

often consumed without appropriate treatment.




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Fig.1. Schematic diagram showing geological cross section, geophysical image and well

monitoring through multi-parameter automatic logger.

In addition to this, long-term effects on cattle and crop farming and established drinking

water supply schemes are also of concern as shown by a number of recently launched projects

(Hearne and Bush, 1996; IWQS, 1999; Wade et al., 2000). Water being a universal solvent has

the ability to dilute certain salts and solids. In this paper the applicability of suitable surface

water harvesting and artificial recharge strategy development at feasible site conditions is

discussed briefly, for groundwater pollution remediation and dilution of contaminant plume due

to recharging water front is conceptually shown as models.




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Types and source of contaminants

The first step in groundwater contamination risk assessment is to identify potential

contaminant sources. Groundwater contamination occurs when man-made products such as

gasoline, oil, road salts and chemicals get into the groundwater and cause it to become unsafe

and unfit for human use. Some of the major sources of these products, called contaminants, are

storage tanks, septic systems, hazardous waste sites, landfills, and the widespread use of road

salts, fertilizers, pesticides and other chemicals. Generally contaminant source identification and

characterization can be more difficult than for other environmental pathways due to several

factors. Basically they can be categorized into three factors as mentioned below:

� First, the presences of groundwater contamination sources are generally hidden from

sight. Even when their existence is known, the characteristics of the sources are difficult

to measure.

� Second, sources that are only present in very small quantities may still pose a potentially

great health risk, depending on the toxicity of the substances.

� Third, groundwater contamination sources are often very long-lived. Disposal of

hazardous material in the ground may pose a threat to groundwater for hundreds or even

thousands of years.

Present source of groundwater pollution / contamination might be the consequence of

activities carried out years ago. Analogously, current waste disposal activities may affect

groundwater quality, and possibly human health, far into the future. This is a natural

consequence of the fact that aquifers are open systems with exchange of water, substances and

energy across the system boundaries. The main inputs of substances into the groundwater occur

from the land surface through the soil zone by infiltration. A contaminant plume due to an

industrial source can spread with time (often many years) with the natural groundwater flow

over large distances of many kilometers and thus poses a long-term danger to water supply

system based on the same aquifer. The groundwater contamination is very high in most of the

industrialized countries.

While the problem is enormous in the industrialized countries for which the statistics are

most readily available, in proportion to population, the problem is undoubtedly of similar

magnitude or more in most developing countries of the world like India. In India, the percentage

of sewered population is nearly negligible in most of the rural areas and is moderate in most of

the medium and small towns.

As a result, the contamination of groundwater by pollution from unsewered areas is one

of the most important environmental problems facing the country. The major groundwater

contamination source compiled by the U.S. Congress office of technology assessment (1984) is

tabulated in Table.1 (Gorden, 1984; Pye et.al., 1983). Of the various types of groundwater

contamination reported from across the world, based on their origin they have been classified

under three major categories as natural, agricultural and industrial contaminants. Each of these

sources is distinctly different from one another, and how to treat toxic plumes and waste




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deposits is one of the most complicated question of the present day, as it has legal, technical,

economical and many scientific aspects.

Fig.2. Schematic diagram showing source of contamination, recharge structures (surface and

subsurface), bore wells monitoring quality of groundwater and its presentation as a line

chart.

Of the above enlisted sources of pollutants, industries and mines are the huge source of

ground water pollution, it produces pollutants that are extremely harmful to people and the

environment, which includes:

� Asbestos – This pollutant is a serious health hazard and carcinogenic. Asbestos fibers

can be inhaled and cause illnesses such as asbestosis, mesothelioma, lung cancer,

intestinal cancer and liver cancer.

� Lead – This is a metallic element and can cause health and environmental problems. It is

a non-biodegradable substance so is hard to clean up once the environment is

contaminated. Lead is harmful to the health of many animals, including humans, as it can

inhibit the action of bodily enzymes.

� Mercury - This is a metallic element and can cause health and environmental problems.

It is a non-biodegradable substance so is hard to clean up once the environment is




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contaminated. Mercury is also harmful to animal health as it can cause illness through

mercury poisoning.

� Nitrates – The increased use of fertilizers means that nitrates are more often being

washed from the soil and into rivers and lakes. This can cause eutrophication, which can

be very problematic to marine environments.

� Phosphates - The increased use of fertilisers means that phosphates are more often being

washed from the soil and into rivers and lakes. This can cause eutrophication, which can

be very problematic to marine environments.

� Sulphur – This is a non-metallic substance that is harmful for marine life.

� Oils – Oil does not dissolve in water, instead it forms a thick layer on the water surface.

This can stop marine plants receiving enough light for photosynthesis. It is also harmful

for fish and marine birds.

� Petrochemicals – This is formed from gas or petrol and can be toxic to marine life.

Water harvesting and artificial recharge

Concept and Application:

Water harvesting refers to collection and storage of rain water. It also refers to other

activities aimed at harvesting surface or groundwater, prevention of losses through evaporation

and seepage. Other hydrological studies and engineering interventions, which are aimed at

conservation and efficient utilization of the limited water endowment of a physiographic unit

such as a watershed is also termed as water harvesting. The various aspects of water harvesting

identified by the working groups in India are construction of permanent/portable storage

structures, farm ponds either for supplemental irrigation or for augmentation of ground water,

check dams, percolation tanks at appropriate sites based on geological consideration; design of

percolation tanks, reclamation/revitalization of traditional water arresting structures, recharge

through wells, control of evaporation from surface water bodies, prevention of seepage looses in

appropriate situations, enhancement of runoff through mechanical and chemical treatment in

catchment area, sub-surface dams to arrest base-flow of ground water, soil and water

conservation practices comprising contour and terrace bunding, control of sea water incursion in

coastal aquifers and control of transpiration without affecting normal plant growth.

Augmentation of ground water resources through artificial recharge can be considered as an

activity which supplements the natural process of recharging the aquifers through percolation of

a fraction of the rainfall through the soil to the water table. Thus it becomes relevant in

situations mostly witnessed in Indian subcontinent, where the rainfall is seasonal (monsoonal)

and is not uniform over the year. Subsequently the quantum of natural recharge is inadequate to

meet the increasing demand on ground water resources.

Methods of Recharge:

Of many methods in artificial recharge, the broad classification to categorize them into two

groups based on the process of artificial inducement of surface water into groundwater system is

direct method, and indirect method. Water from surface sources are conveyed or stored in-situ at

places above the aquifer areas, where it is made to percolate and recharge the ground water, are

coined as direct method. Were as in the latter, the transfer of surface water is induced or it takes




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place as a consequence of a human activity which is not specifically aimed at recharging the

aquifers.

Induced recharge is effected by locating the ground water abstraction wells near influent

streams. The second type of indirect recharge is that arising out of seepage from stream or canal

or lake beds and return flow from irrigation. Under direct recharge, surface water from a river or

lake is transported to a suitable site, where it is made to enter the aquifer, thus increasing the

ground water supply.

In this paper the application of direct recharge in contaminant transport remediation is

explored. For direct recharge many methods are available and they can be grouped under three

categories: a) when the aquifer is shallow, water spreading may be applied by flooding over

areas or conveying water to basins and ditches; b) when an aquifer is situated at moderate depth,

the aquifer can be recharged through flooding of pits and shafts and c) in case of high

overburden thickness or confining aquifer conditions, recharge can only be effected by injecting

the water directly into the aquifer using boreholes/tube wells.

Application in groundwater remediation:

During the past decade, ground water scientists and engineers have devised a number of

methods to contain and or remediate groundwater contamination. The groundwater pollution

remediation technologies can be generally classified into onsite techniques and in-situ

techniques. The commonly used onsite techniques are pump and treat method, air sparing soil

water extraction, in-situ redox manipulation, permeable reactive barriers, phytoremediation etc.

The in-situ technologies, which directly remediate contaminated groundwater, are still not well

developed, primarily because site characterization is complex, expensive and inaccurate.

Moreover, contaminant plume and its migration with time are often difficult to define exactly.

So far the concept of artificial recharge and surface water harvesting was applied for

sustainability of aquifer system and also for in-situ dilution of groundwater bearing excessive

fluoride, arsenic, and other geogenic contaminants. The concept of aquifer recharge through

human intervention of surface water inducement at appropriate site locations can be extended in

groundwater remediation studies on a large scale. Especially in shallow to moderately deeper

polluted aquifer system, application of artificial recharge can be explored in in-situ dilution of

contaminants in groundwater. Some of the recharge measures and strategies which can be

applied in conjunction with other pre-existing techniques are briefly described further in this

paper.

Artificial recharge remediation technology

Surface Water Harvesting is the most common form of water harvesting practiced all

over the world. In many centuries construction of percolation ponds and irrigation tanks were

practiced to harvest surface runoff. The sizes of the tanks and their influential command area

vary widely. In India, the culture of surface water harvesting is widely seen in the southern

peninsular shield area indicating the water stress mainly in drinking water sector.




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Fig.3.Conceptual model showing cascading format of artificial recharge structures creating an

intermittent subsurface zone of dilution of migrating contaminant plume.

The basic objective in constructing a water harvesting structure is to collect and retain

the maximum possible amount of runoff generated from its catchment area. In general, the size

of the structure and design of a SWHS (Surface Water Harvesting Structure) also plays an

important role in its efficacy. Based on extensive research and study carried out by different

schools of thoughts all over the world, it is suggested that the smaller the catchment area, the

more efficient is the runoff collection (Evenrari, 1971; Boughton and Stone, 1985).

This concept can be extended in deliberating groundwater contaminant dilution at

feasible site locations. Apart from water crises there are several blocks in semi arid Indian

subcontinent where the drinking water sector is facing quality problem from variable sources.

As per Indian standard specification for drinking water IS: 10500-1983, there are certain

characteristics with specifications of groundwater shown in Table.2. Any of these components

beyond permissible limit is a contaminant and can causes adverse affects to life forms.




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Table-1: Source of groundwater contamination.

CATEGORY I- SOURCES DESIGNED TO

DISCHARGE SUBSTANCES

Nonhazardous waste

Subsurface percolation (e.g., septic tanks and cesspools) Nonwaste

Injection wells Open burning and detonation sites

Hazardous waste Radioactive disposal sites

Nonhazardous waste (e.g., brine disposal and drainage) CATEGORY III- SOURCES DESIGNED TO

RETAIN SUBSTANCES DURING TRANSPORT

OR TRANSMISSION

Non waste (e.g., enhanced recovery, artificial recharge,

solution mining, and in situ mining)

Pipelines

Land application Hazardous waste

Waste water (e.g., spray irrigation ) Nonhazardous waste

Waste water byproducts (e.g., sludge) Nonwaste

Hazardous waste Material transport and transfer operations

Non hazardous waste Hazardous waste

CATEGORY II - SOURCES DESIGNED TO

STORE, TREAT, AND/OR DISPOSE OF

SUBSTANCES; DISCHARGE THROUGH

UNPLANNED RELEASE

Nonhazardous waste

Landfills Nonwaste

Industrial hazardous waste CATEGORY IV-SOURCES DISCHARGING

SUBSTANCES AS CONSEQUENCE OF OTHER

PLANNED ACTIVITIES

Industrial nonhazardous waste Irrigation practices (e.g., return flow)

Municipal sanitary Pesticide applications

Open dumps, including illegal dumping (waste) Fertilizer applications

Residential (or local) disposal (waste) Animal feeding operations

Surface impoundments De-icing salts application

Hazardous waste Urban runoff

Nonhazardous waste Percolation of atmospheric pollutants

Waste tailings Mining and mine drainage

Waste piles Surface mine-related

Hazardous waste Underground mine-related

Nonhazardous waste CATEGORY V- SOURCES PROVIDING

CONDUCT OR INDUCING DISCHARGE

THROUGH ALTERED FLOW PATTERNS

Materials stockpiles (non waste) Production wells

Graveyards Oil (and gas) wells

Animal burial Geothermal and heat-recovery wells

Above-ground storage tanks Water – supply wells

Hazardous waste Other wells (non waste)

Nonhazardous waste Monitoring wells

Nonwaste Exploration wells

Underground storage tanks Construction excavation

Hazardous waste CATEGORY VI- NATURALLY OCCURING

SOURCES WHOSE DISCHARGE IS CREATED

AND/OR EXACERBATED HUMAN ACTIVITY

Nonhazardous waste Ground water-surface water interactions

Nonwaste Natural leaching

Containers

Hazardous waste

Saltwater intrusion/brackish water up coning (or

intrusion of other poor-quality natural water)

Source: Office of Technology Assessment (1984)




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Table-2: Specifications for Drinking Water Quality.

S. No Characteristics Maximum

Permissible

limits

Adverse Effects Beyond

Permissible limits

Alternative Extended

limits if no toxicity

confirmed

1. Color

(Hazen units)

10 Consumer

acceptance decreases

50

2. Odor Unobjectionable -- --

3. Taste Agreeable -- --

4. Turbidity (niu) 10 Consumer acceptance decreases 25

5. T.D.S.(mg/l) 500 Palatability decreases.

May cause gastrointestinal

irritations

3000

(WHO Limits:1500)

6. pH value 6.5 to 8.5 Mucous membrane affected 9.2

7. Total hardness as

CaCO3 (mg/l)

300 Encrustation and adverse effects

on domestic use

600

8. Calcium as Ca(mg/l) 75 -do- 200

9. Magnesium 30 -do- 100

10. Copper as Cu(mg/l) 0.05 Astringent taste discoloration &

corrosion of metallic parts

1.5

11. Iron as Fe(mg/l) 0.3 Taste & appearance affected.

Promotes iron bacteria

1.0

12. Manganese as Mn

(mg/l)

0.1 Taste & appearance affected 0.5

13. Chloride as Cl(mg/l) 250 Taste & palatability reduced. 1000

14. Sulphates as SO4

(mg/l)

150 Gastrointestinal irritations when

magnesium or sodium are

present

400 ( provided Mg

does not exceed 30)

15. Nitrate as NO3(mg/l) 45 Methane moglobinemia

Takes place

No relaxation

16. Fluoride as F(mg/lt) 0.6-1.2 Low Fluoride cases are linked

with dental care. Above 1.5

causes fluorosis

1.5

17. Phenolic compounds

as C H OH(mg/l)

0.001 Objectionable taste and odor 0.002

18. Mercury as Hg(mg/l) 0.001 Toxicity increases No relaxation

19. Cadmium as Cd(mg/l) 0.01 -do- -do-

20. Selenium as Se(mg/l) 0.01 -do- -do-

21. Arsenic as As (mg/l) 0.05 -do- -do-

22. Cyanide as CN(mg/l) 0.05 Water becomes toxic -do-

23. Lead as Pb(mg/l) 0.1 -do- -do-

24. Zinc as Zn(mg/l) 5 Astringent taste opalescence 15

25. Anionic detergents as

MBAS (mg/l)

0.2 Frothing in water 1

26. Chromium as Cr (mg/l) 0.05 Carcinogenic No relaxation

27. Poly nuclear aromatic

hydrocarbons as PAH

(mg/l)

__ -do- __

28. Mineral oil(mg/l) 0.01 Undesirable taste and odor 0.03

29. Residual free chlorine

(mg/l)

0.2

(Minimum)

__ 0.5 for protection

against viral infection

Source : Indian standard specification for drinking water IS: 10500-1983




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There are several criteria based on which any artificial recharge structures are designed and

executed for harvesting surface runoff. Some of the general features which are to be considered

in planning site selection is geomorphology, geology, rainfall pattern, depth to water table, soil

type, order of stream present etc. Surface geophysical investigation helps in understanding the

subsurface distribution of the lithology, aquifer depth, presence of hydraulic barrier like dykes,

depth to the basement etc. With the recent development in technology, the surface geophysical

data acquisition and presentation has improved many folds, which gives a 2D and 3D image of

the subsurface for a desired depth of interest. Based on these investigated results in

corroboration with appropriate elevation correction, sites are selected for puncturing the aquifer

to a desired depth, which is known as bore wells or tube wells.

These observation bore wells are used for monitoring the quality of groundwater and also to

understand the correlation of ground water level with seasonal variation. With the advent of

multi-parameter automatic water level recorders, the aquifer response to natural and induced

recharge has become more appropriate, as more than two parameter can be recorded and studied

under in-situ condition over a considerable period of time. A schematic diagram showing the

application of geophysics in site allocation and mapping of subsurface, followed by bore well

execution and monitoring is shown in Fig.1.

Industrial, mining or domestic waste ground sites pose major threat to groundwater

contamination on a large scale with time. Several attempts have been made in the recent past,

across the country to map the subsurface migration of this contaminant plume. Deeper migration

of the contaminant through the zone of unsaturation to the aquifer is a complex phenomenon to

understand (Rowe and Booker, 1990; Tiwary et.al., 2005). Mining waste, factory outlets or

domestic waste dump sites are usually planned without proper subsurface understanding of the

dump site.

It is a usual practice to preoccupy any vacant land devoid of day to day human activity,

close to the vicinity of the parent mining plant or factory. There are instances where due to non

availability of land, agricultural land or any other land close to the urban area are converted into

waste dump sites. Considering a case were the source of any known dump site is located and the

water quality is monitored in and around the dump site before and after commissioning of the

site is schematically represented in Fig.2. As discussed earlier, based on geophysical

investigation and proper understanding the subsurface geology and geomorphology, bore wells

are drilled for monitoring the water quality through multi parameter loggers. The response in

terms of concentration variation over time is shown as an inset in Fig.2. Contaminants in

groundwater have a tendency to migrate along the hydraulic gradient through highly permeable

formation. Once the source of contaminant and its direction of migration is known, accordingly

suitable sites across existing stream courses are selected for investigation for site feasibility to

construct appropriate artificial recharge structure, like check dam as shown in the figure. The

basic purpose for such a structure is to dilute the contaminant beyond its area of influence.

Depending upon the type of contaminant like excess chlorine, pigments etc., can be restricted in

its course of migration by constructing a subsurface barrier across the hydraulic gradient. The

barrier can be a simple filter media or can be in combination with activated charcoal and filter

media (coarse gravel and sand bed).




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The subsurface barrier is followed by a surface recharge structure like check dam or

percolation tank on its downstream. This will help in further dilution of contaminated water

filtering out of the subsurface barrier. Under favorable conditions recharge structures can be

designed across existing stream courses, downstream of contaminant plume migration in a

cascading format, so as to cause intermittent dilution of the contaminated groundwater flow. The

conceptualized visual of artificial recharge is shown in Figure.3. Further in order to understand

the rate of dilution and check the efficiency of these structures over groundwater pollution

mitigation approach, observational bore wells are to be drilled at regular intervals on either side

of these structures and are to be monitored in space and time.

The concept of artificial recharge structure can be extended in pollution mitigation studies

under favorable site criterions, as it requires no addition of artificial chemicals or processing

plant. Several attempts have been made successfully in mitigating excess groundwater fluoride

and sustaining the source for drinking water purpose through integrated geohydrological and

artificial recharge approach (Andrade, 2009).

Conclusion

This paper has been attempted to highlight the effectiveness and suitability of artificial

recharge and water harvesting in integration with different site criterions in mitigating some of

the pollutants in groundwater. Groundwater contamination is a problem which arose with the

human race in the field of industrialization and urbanization. There are several methodologies

and strategies adopted for tackling any respective problem, which either ends up with improper

management or inadaptability due to high cost of execution. Water harvesting and artificial

recharge depends mainly on natural precipitation over an area of study. Depending upon the

subsurface information and geohydrological investigations, appropriate structures are

recommended for in-situ dilution of contaminated groundwater flow. Of the many contaminants,

some of them can be managed through this approach. Also the cost of maintenance and

execution is negligible in course of time. The approachability of this methodology is represented

as conceptual models in this paper, which might require further refinement from engineering

point of view. Acknowledgement: The authors are thankful to Dr.Y.J.Bhaskar Rao, acting Director of National Geophysical

Research Institute for his encouragement and support towards the submission of this article for publication. We

also extend our gratitude towards Dr. R.N. Atavale and Dr. D.Muralidharan for educating us with the concept and

prospects of recharge studies in Indian scenario.

Suggested Readings:

1. Hearne C. L and Bush R. A (1996) Investigation into the impact of diffuse seepage from gold-mines in the

Klerksdorp region on water quality in the Vaal River, Phase 1. Report No. CED/011/96 for the Klerksdorp

Mine Managers Association (KMMA). Johannesburg. Unpublished.

2. IWQS (Institute for Water Quality Studies, DWAF) (1999) Report on the radioactivity monitoring programme

in the Mooi River (Wonderfonteinspruit) catchment. Report No. N/C200/00/RPQ/2399.

3. Wade P.W, Woodbourne S, Morris WM, Vos P and Jarvis NV (2000) Tier 1 Risk Assessment of Radionuclides

in Selected Sediments of the Mooi River. WRC-Project No K5/1095. 93 pp.




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4. Gordon, W. (1984) A Citizens Handbook on Groundwater Protection. New York: Natural Resources Defense

Council, Inc.

5. Pye, V.I., Patrick, R., and Quarles, J. (1983) Groundwater Contamination in the United States. Philadelphia:

University of Pennsylvania Press.

6. Boughton, J.C and Stone, J.J, “Variation of runoff with watershed area in semi-arid location”, 1985, Jr. of Arid

Environment, Vol.9, pp.13-25.

7. Evenari, M., “Stone mounds and the mechanics of runoff”, a chapter in the book, “The Negev: the challenge of

a desert, Oxford University Press, U.K. 1971, pp.127-147.

8. Rolland Andrade, “Sustainable Groundwater Development and Quality Management in Nalgonda District –

Andhra Pradesh through Integrated Geohydrological and Artificial Recharge Approach”, Ph.D Thesis, 2009,

Osmania University. Pages 1-280.

9. Ethan Grossman and Jennifer McGuire, “Groundwater remediation”, http://oceanworld.tamu.edu / resources

/environment-book / groundwaterremediation.html, 2008.

10. R. K. Tiwary, R. Dhakate, V. Ananda Rao and V. S. Singh, “Assessment and prediction of contaminant

migration in ground water from chromite waste dump”, Environ Geol (2005) 48: 420–429.

11. R.Kerry Rowe & John R. Booker, “Contaminant migration through fractured till into an underlying aquifer”,

Canadian Geotech. Jour. 27, 484-495 (1990).

Rolland Andrade, R. Rangarajan and D.N.V Lakshmi Devi belong to National Geophysical

Research Institute, Council of Scientific and Industrial Research, Hyderabad, INDIA

Corresponding author: [email protected]

Contaminated Groundwater Remediation– Usage of Water Harvesting under Favorable Circumstances

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