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1.
2.
Analyses of 126 samples collected from 18 dug wells in the shallow basaltic aquifer over a period of 7 months have revealed
spatial as well as temporal changes in the chemical properties of groundwater. While the temporal changes have been attributed
to dilution and concentration phenomena governed by climatic factors, the spatial variations in the geochemical characteristics
of groundwater appeared to be related to pollution due to effluents from the Mula Sugar Factory. The cause of groundwater
pollution is the effluent carried by a stream flowing through the area. Fluctuations in the groundwater table, influent water
quality character of the stream, less capacity to accommodate large volume of effluent and occurrence of zero base flow (under
natural conditions) in the stream are the factors favoring infiltration of constituents of waste water into the underlying
weathered basaltic aquifer. Pollutants have entered into the shallow aquifer by downward percolation through the zone of aeration
to form a recharge mound at the water table and, further, lateral movement below the water table. The plume of polluted groundwater
has a lateral extent of a few meters in the upstream area and more than 400 m on either side of the stream in the downstream
part. The zone of polluted groundwater has an areal extent of more than 3.5 km2. Groundwater is the only source available for drinking and agricultural purposes. It is recommended that the base of the
lagoons and the stream used for release of plant effluent should be waterproofed for the protection of groundwater in the
Sonai area.
Received: 30 April 1997 · Accepted: 23 September 1997 相似文献
3.
Groundwater quality in the Niva River basin, Chittoor district, Andhra Pradesh, India 总被引:2,自引:0,他引:2
This study was made to assess the groundwater quality in relation to agricultural and domestic uses in a part of the Peninsular
Archean granite and gneissic complex of India. Water samples were collected from the existing wells in the Niva River basin,
Chittoor district, Andhra Pradesh, India and analysed for major ions. The analytical data, processed and interpreted acoording
to the WHO standards, reveal that, in general, the groundwater is suitable for both agricultural and domestic uses, exept
in a few locations. High concentration of nitrates were observed in some of the wells (both agricultural and domestic) that
are affected by the impact of industrial effluents. Multiple regression analysis was performed and used as a positive predictive
tool in understanding the chemistry of the groundwater.
Received: 2 May 1996 / Accepted: 14 October 1996 相似文献
4.
A study of the pollution of the Aries River (Romania) using capillary electrophoresis as analytical technique 总被引:4,自引:0,他引:4
This paper examines two issues, the extensive pollution occurring in the Aries River, NW Romania, as a result of unchecked
discharge of mining effluents into the river system, and the suitability of capillary electrophoresis (CE) as an analytical
method for investigations into water chemistry. The results confirm the first objective by providing details on the pollution
of the Aries River and its geochemical system and demonstrate the usefulness of CE. In its upper reaches, the river system
is characterized by high contents of SO4
2– as a direct result of acid mine effluents and the oxidation of sulphide minerals on mine dumps as well as inflows from settling
ponds. Although continuous dilution by natural branch waters and natural water-rock interaction reduces the pollution to some
extend, the total level of SO4
2– remains above European averages. The waters of the Aries River, by comparison, contain contents of Cu2+ and Zn2+ up to 100 times higher than those of unpolluted river water.
Received: 1 November 1999 · Accepted: 3 April 2000 相似文献
5.
Groundwater quality in parts of Central Ganga Basin, India 总被引:1,自引:0,他引:1
This paper deals with the drinking water quality of the Ganga-Kali sub-basin which occupies 1300 km2 over parts of Aligarh and Etah districts. Water samples were collected from shallow and deep aquifers and were analyzed for
major ions and trace elements. The analytical data were interpreted according to published guidelines. Chemical analysis shows
that the groundwater in the basin is alkali bicarbonate type. Trace element studies of water from the shallow aquifer show
that the concentration of toxic metals Fe, Mn, Cd, Pb, and Cr+6 are above permissible limits which may present a health hazard. The water from the deep aquifer is comparatively free from
contamination. The aquifers are subject to contamination due to sewage effluents and excessive use of fertilizers and pesticides
in agriculture.
Received: 7 December 1998 · Accepted: 2 March 1999 相似文献
6.
Groundwater pollution due to discharge of industrial effluents in Venkatapuram area, Visakhapatnam, Andhra Pradesh, India 总被引:1,自引:0,他引:1
Hindustan Polymers Limited was established in the Venkatapuram area in the northwestern part of Visakhapatnam urban agglomeration.
Untreated industrial effluent from the plant is discharged with total dissolved solids concentrations reaching up to 6500 mg/l.
The groundwater pollution was identified as early as 1981 and a hydrogeologic and water-quality database is available from
1981. The groundwater quality in the plant environs is found to be in the range of 3500–4500 mg/l. Major chemical constituents
of industrial-waste waters consist of Na, Cl, and SO4. Some characteristic parameters of the aquifer were estimated. The available hydrogeologic and hydrologic data was analyzed
to conceptualize the groundwater regime. A mathematical groundwater flow model was constructed to compute the hydraulic head
at the center of finite-difference grid. The computed head distribution and effective porosity of the formations were used
to calculate the groundwater flow velocity. The computed velocity field was ultimately used to prognose the pollutant migration
in groundwater accounting for the advection and dispersion processes in the mass transport model and for determining the time-dependent
pathlines of pollutant. Areal migration of pollutants from the source was predicted up to year 2002.
Received: 23 December 1996 · Accepted: 9 September 1997 相似文献
7.
The San Antonio-El Triunfo mining district, located at a mountainous region 45 km south-east of La Paz, Baja California,
has been worked since the late 1700s. Mine waste material produced during 200 years of mineral extraction area poses a risk
of local groundwater pollution and eventually, regional pollution to the Carrizal (west basin) and the Los Planes (east basin)
aquifers. There are different types of deposits in the mining area. These are dominated by epithermal veins, in which arsenopyrite
is an important component. Carrillo and Drever (1998a) concluded that, even though the amount of mine waste is relatively
small in comparison to the large scale area, significant As in groundwater derived from the mine waste piles is found locally
in the groundwater. This paper shows the results of geochemical analyses of groundwater samples from the San Antonio-El Triunfo
area and the Carrizal and Los Planes aquifers during several years of monitoring (1993–1997). The highest values of total
dissolved solids (TDS) and As are in the mineralized area where the mining operations occurred (∼1500 ppm TDS and 0.41 ppm
As). The lowest concentrations of TDS and As are, in general, away from the mineralized area (∼500 ppm TDS and 0.01 ppm As).
Sulfate and bicarbonate (alkalinity) are, in general, high near the mineralized area and low away from it. The arsenic concentrations
vary seasonally, especially after the heavy summer thunderstorms. Geochemical modeling (MINTEQA2 and NETPATH) and analysis
of the regional geochemical evolution of the groundwater from the mining area towards the aquifer of Los Planes shows that
the most likely hydrochemical processes include: dilution, precipitation of calcite, and adsorption of As onto surfaces of
iron oxyhydroxides (ferrihydrite). These processes act as natural controls to the extent and amount of As pollution in the
Carrizal and Los Planes aquifers.
Received: 4 May 1999 · Accepted: 22 February 2000 相似文献
8.
Two waste-disposal sites (old and new) in Calabar Municipality, SE Nigeria were evaluated to assess their suitability as
landfill sites and their impact on the groundwater. The field investigation included surface geological/hydrogeological and
geochemical studies. Leachate and groundwater were sampled and analysed for 3 months (April, May and June, 1997) for geochemical
characterisation. The results indicate that the two waste-disposal sites in the Calabar Municipality do not meet the requirements
as landfill sites. Physico-chemical analyses for temperature, pH, conductivity, dissolved oxygen, biological oxygen demand
after 5 days of incubation (BOD5), sulphate, nitrates, nitrite, trace and major elements in the leachate known to impact human health and the environment,
indicate high levels of pollution. The values for groundwater in the vicinity of the disposal sites were found to be within
the World Health Organisation (WHO) permissible limit.
Received: 29 March 1999 · Accepted: 3 January 2000 相似文献
9.
Rio Tinto estuary (Spain): 5000 years of pollution 总被引:6,自引:0,他引:6
R.A. Davis Jr. A. T. Welty J. Borrego J. A. Morales J. G. Pendon J. G. Ryan 《Environmental Geology》2000,39(10):1107-1116
Mining of massive sulfide deposits in southwestern Spain extending back to the Copper and Bronze Ages has resulted in the
pollution of the Rio Tinto fluvial-estuarine complex, the site of Columbus' departure for the New World in 1492. Additional
sources of potential pollution include the large industrial complex at Huelva near the lower portion of the estuary. Extensive
analysis of surface sediment samples and cores has established that there are no geographic trends in the distribution of
the pollutants, which include Cu, Fe, Pb, Zn, Ti, Ba, Cr, V and Co. These data have, however, demonstrated that tidal flux
within the estuary carries phosphorus and perhaps other elements from the industrial complex at Huelva to the tidal limit
of the system, several kilometers upstream from the discharge site. Radiometric analysis of short cores shows that sedimentation
rates over at least the past couple of centuries have been about 0.3 cm/year. These data and that from a single deep core
demonstrate that the estuary was polluted from mining activity long before the large-scale operations began in the late nineteenth
century.
Received: 3 May 1999 · Accepted: 18 October 1999 相似文献
10.
Ankara Creek is often subjected to overflowing of sewage caused by rainfall or direct discharge of raw sewage. Alluvial aquifers
adjacent to Ankara Creek and its tributaries have considerable groundwater potential. The present status of groundwater quality
is far from drinking water standards. Groundwater contamination in Ankara is suspected to be caused by Ankara Creek which
is heavily polluted by raw sewage discharge, surface runoff and other common sources. In order to investigate the influence
of heavily polluted Ankara Creek on the groundwater contamination in the adjacent alluvial aquifers, five sampling stations
on Ankara Creek and 25 water wells were monitored during 1996. At five different sampling periods, water samples were collected
from both surface water and groundwater. Chemical analyses of basic ions, pollution parameters and heavy metals in natural
waters were carried out. The organic pollution prevails in Ankara Creek whereas total dissolved solids (TDS) and heavy metal
concentrations are considerably low. Starting from the idea that Ankara Creek somewhat influences the groundwater quality
and the contaminants in groundwater should attenuate with respect to distance, a series of water wells in a certain area,
each having different distance from the creek, were examined using four pollution parameters. It is concluded that Ankara
Creek barely influences the aquifer systems in connection. This is attributed to two reasons: rapid attenuation of contaminants
due to dilution in groundwater and a blanket of very fine sized materials covering the bottom of Ankara Creek.
Received: 28. April 1997 · Accepted: 23. February 1998 相似文献
11.
Sahebrao Sonkamble V. Satish Kumar B. Amarender P. M. Dhunde S. Sethurama K. Raj Kumar 《Journal of the Geological Society of India》2014,83(3):279-289
The tannery effluents discharged by the existing units on either side of the Palar river at Ambur town (known for tannery industry), has resulted in vertical and lateral spread of pollution. The study area of 55.3 km2 is situated on a granitic terrain of Archaean age with undulating topography and hillocks. The shallow aquifers, in flood plain and valley fills of the river are highly polluted (with EC: 15340 μS/cm) by tannery effluents making groundwater unfit for any use, hence the local population (20000) face health hazards and shortage of potable water. Hydrogeological, geophysical and in-situ groundwater quality measurement were carried out to demarcate fresh groundwater zones and to delineate lateral and vertical extent of pollution. The results show, brackish aquifer was characterized by low order of resistivity (<20 Ω-m) with a thickness of 8.5 to 28 m located in the flood plains, valley fills, and partially in hard rock formations, whereas the fresh water aquifer resistivity varying from 23 to 216 Ω-m in hard rock. Further, these results were correlated with the water quality data and Ground Penetrating Radar (GPR) signals. The integrated studies revealed that pollution due to tannery effluents has spread over an area of 33.4 km2 (60.4 %) on either side of the river and only a small area of 21.9 km2 (39.6 %) was identified as fresh groundwater zone, which has to be conserved and exploited in sustainable manner for future generations. 相似文献
12.
B. K. Bhadra Suparn Pathak J. R. Sharma 《Journal of the Geological Society of India》2013,82(6):675-691
Groundwater pollution due to industrial effluents from textile units around Pali city area is the major concern to the local villagers and the district administration. Indiscriminate discharge of these effluents in the past two decades caused severe damage to the agricultural land and groundwater resources within 3 km buffer zone of the Bandi river. Remote Sensing and GIS techniques are found to be better tools in assessing the damage in agricultural crops during 1997 and 2006 with the help of high resolution satellite images. Groundwater fluctuation trend with annual rainfall pattern during 1985 and 2005 indicate good recharge in the study area. Detailed analysis of groundwater quality parameters (TDS, Cl and SO4) and heavy metals (Cu, Pb, Zn, Fe, Cd and Cr) for 1997–98 indicates maximum concentration around Chatelao village and Dholera Jagir in the downstream direction of Bandi river. However, temporal analysis of groundwater samples collected in January, 2009 shows marginal decrease in concentration of TDS, Cl, SO4, Pb and Cu in both groundwater as well as river effluents. Slight improvement in water quality especially heavy metals in the last 12 years (1998–2009) may be attributed to the appropriate measures (treatment of wastewater and solid waste disposal) taken by the establishment of three Common Effluent Treatment Plants (CETP) in Pali city area. However, a few stringent actions may be taken to avoid direct discharge of the effluents into Bandi river. 相似文献
13.
The use of statistical techniques in studying the causes of geochemical variations in aquifers can provide important results
which cannot be derived in other ways. In this study, data from the Wadi Shueib catchment area in Jordan is evaluated, using
principle component factor and multivariate factor analysis in order to better understand the variablility in groundwater
chemistry and evaluate the sources of pollution and the susceptibility of these aquifers to the different sources of pollution.
This study clearly demonstrates that these statistical techniques can help determine the various mechanisms causing chemical
variation in the aquifers and the relative susceptibility of each aquifer to different types of pollution.
Received: 13 March 1996 · Accepted: 18 June 1996 相似文献
14.
Groundwater nitrate pollution in an alluvium aquifer, Eskişehir urban area and its vicinity, Turkey 总被引:1,自引:0,他引:1
A large amount of the water requirement (municipal, industrial, etc.) of Eskişehir city, Turkey, is supplied from groundwater
via wells in the urban area. The groundwater in the Eskişehir Plain alluvium has been polluted by municipal and industrial
wastewater, and agricultural activities. The nitrate concentrations at nine sampling points on Porsuk River, the main water
course in the plain, ranged from 1.5 to 63.3 mg/l during the period from July 1986 to August 1988. In the same period, the
nitrate concentrations measured in water from 51 wells ranged between 2.2–257.0 mg/l. The nitrate content of the groundwater
samples was 34.2% above 45 mg/l, the upper limit for nitrate in drinking water standards. High nitrate levels were observed
in water from wells in the central and eastern parts of the urban area. The nitrate content of the well water is subject to
seasonal fluctuation. In general, low nitrate concentrations were observed in wet seasons, and high ones in dry seasons.
Received: 16 April 1996 · Accepted: 2 October 1996 相似文献
15.
S. Selvam S. Venkatramanan P. Sivasubramanian S. Y. Chung C. Singaraja 《Journal of the Geological Society of India》2017,90(1):62-68
In this work the major and trace elements pollution levels in groundwater of Tuticorin city of Tamil Nadu was investigated. This coastal city with numerous large and small scale industries has increasingly affected the water quality by dumping effluents. The mean major and trace elements levels in groundwater in descending order: Si > Sr > Zn > Fe > Rb > Se > Al > Mn > Cu > As > Cr > Ba > V > Ni > Pb > Mo > Co > Sb > Cd > Ag. The concentrations of As, Se, Pb, Ba, Al, Fe and V (0.084, 0.150, 0.057, 0.837, 0.357 and 0.052) in some of the groundwater samples exceed the standard value of world health organization (WHO, 2004). Interrelationship between the elements was done by correlation matrix and factor analysis which indicates the contribution from industrial and irrigation fields. Spatial interpolation of inverse distance method (IDW) maps of all the elements suggested that discharge of effluents from chemical factory (STERLITE, TAC, SPIC, HEAVY WATER PLANT, NILA SEA FOODS), municipal wastewater, fertilizers were added to the natural sources. Results of this research suggests that proper measures should be taken to protect the vital groundwater resources in the Tuticorin city. 相似文献
16.
Current trends and future challenges in groundwater vulnerability assessment using overlay and index methods 总被引:66,自引:7,他引:59
The concept of groundwater vulnerability is a useful tool for environmental planning and decision-making. Many different
methods have been developed for assessing this vulnerability. Hydrogeologists have failed to reach a consensus concerning
the definitions of and reference terms for groundwater vulnerability assessment. Therefore, a review of vulnerability assessment
and mapping methods providing a new classification system is necessary. This is focused on techniques that use the overlay
and index class methods. New research challenges in vulnerability assessment are identified, especially the need for developing
dynamic links between numerical models and overlay and index methods.
Received: 28 October 1998 · Accepted: 31 May 1999 相似文献
17.
The Indian subcontinent has the largest semi-arid tropical (SAT) area among developing nations. The State of Andhra Pradesh
falls under the SAT region in India and is mostly covered by compact and hard rocks, characterized by seasonal rainfall of
a highly fluctuating nature, in both space and time. As a consequence of the green revolution and an increase in industrial
activity, there has been an increase in the utilization of groundwater resources during the last two decades in Andhra Pradesh.
The development has also caused a number of problems, such as water table decline, decrease in well yields and seawater intrusion.
Although major irrigation projects have contributed to improved agricultural production, the associated problems of waterlogging,
salinization and loss of valuable bioresources have led to the gradual degradation of the land, affecting agricultural productivity.
Surface water and groundwater have also been polluted in several parts of the State because of untreated discharge of effluents
from the industries into nearby streams or open lands. A brief account of the overall scenario of the hydrogeological framework
and geo-environmental effects on the groundwater regime in Andhra Pradesh is presented. Possible management practices and
conservation methods are suggested.
Received: 9 August 1999 · Accepted: 10 July 2000 相似文献
18.
M. Thangarajan 《Environmental Geology》1999,38(3):209-222
Palar River Basin, a crystalline rock region in North Arcot District (Tamil Nadu), India, possesses vast groundwater potential
along and near the river course and its lands are fertile. Serious contamination of both surface water and groundwater has
been reported in this basin as a result of uncontrolled discharge of untreated effluents by the tanning industries for the
last three decades. The health of the rural farming community and people working in the tanning industries has been seriously
affected and they are suffering from occupational diseases such as asthma, chromium ulcers and skin diseases. About an 11000
hectares area of fertile land has lost its fertility. Total dissolved solids (TDS) concentration in groundwater at some pockets
varies from 3000 to 10000 mg/l. As the discharge of effluents is continuing, a prognosis of further pollutant migration is
carried out using a mathematical model. A numerical model of the Upper Palar River Basin was developed using the finite difference
technique coupled with method of characteristics and used to predict TDS migration for the next 20 years. Sensitivity analysis
was carried out to identify the parameters which are influencing the contaminant migration. Sensitivity analysis shows that
advection and not dispersion is the predominant mode of solute migration in Palar Basin. Prognosis using the model confirms
that the polluted area zone as well as the concentration of pollutants in the groundwater will continue to increase in future.
The study also indicated that even if the pollutant sources are reduced to 25% of the present level, the TDS concentration
level in the groundwater, even after 20 years, will not be reduced below 50% of its 1992 level.
Received: 20 June 1998 · Accepted: 26 October 1998 相似文献
19.
Hydrochemistry of groundwater is largely determined by both natural processes, such as dissolution, cation exchange, mixing,
evaporation; and anthropogenic activities, which can affect the aquifer systems by contaminating them or by modifying their
hydrological cycle. Both natural and anthropogenic processes vary in time and space; which is reflected in groundwater hydrochemistry
variation. The objective of this study is the determination of the main hydrogeochemical processes that affect the quality
of shallow groundwaters in the Grombalia basin, located in the Cap Bon Peninsula, north-eastern Tunisia. In this area, the
chemical composition of groundwater is mostly characterized by Na–Cl–NO3–Ca water type which reveals the implication of natural and anthropogenic major factors. Natural factors are dissolution of
evaporatic minerals, i.e. halite and gypsum and cation exchange with clays, while anthropogenic factors are pollution with
industrial Sr-rich waste water and return flow of irrigation water, highly contaminated by MgSO4 and methyl-bromide fertilizers. 相似文献
20.
The impact of human activities in the Malia coastal area (Crete) on groundwater quality 总被引:1,自引:0,他引:1
N. J. Lambrakis 《Environmental Geology》1998,36(1-2):87-92
The evaluation of the long-term effects of seawater intrusion into the aquifers due to negative water balance and nitrate
pollution of drinking-water quality due to human activities requires detailed knowledge of both the transport of the chemical
constituents and the geochemical processes within aquifers. Hydrogeological and hydrochemical studies in the unconfined aquifer
of Malia have provided the necessary data to define the areas at increased risk from these phenomena. The solution of the
second Fick's low under given boundary conditions gave an estimate of the propagation of groundwater pollution by NO3
–. Additionally, in order to simulate the ion concentration changes during a period, for example a period of positive water
balance or refreshening, groundwater transport and cation exchange reactions were modelled using the code PHREEQM.
Received: 25 July 1997 · Accepted: 4 November 1997 相似文献