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Groundwater Biological Quality in Abuja FCT: Myths and Realities of Point and Non-Point Pollution of Fractured Rock Aquifers
Richard Ayuk II Akoachere, Areakpoh Thomson Eyong, Marcelle-Carole Pami Ngassam, Jane-Francis Kihla Akoachere, Simon Oko Okpara, Omogbemi Omoloju Yaya, Felix Akumcha Mbaabe
Open Access Library Journal (OALib Journal) , 2019, DOI: 10.4236/oalib.1105734
Abstract:
The quality of groundwater is three fold: physical, chemical and biological. For water to be fit for human consumption, it must have satisfied all three quality aspects. Therefore, the groundwater biological quality of Abuja FCT can never be over emphasized since the wellbeing of the citizens of the capital territory, seat of the government of Nigeria, is of strategic importance. There are myths and realities about the biological quality of groundwater in fractured rock aquifers which must be clarified. Groundwater plays a very important role in the development of Abuja, Nigeria’s Capital as many private, government, and households establishments depend solely on hand-dug wells and boreholes for their daily water needs. This study evaluates the biological quality using total bacterial density (TBD), total coliform (TC), coliform bacteria (CB), faecal coliform (FC), total bacteria count (TBC), and salmonella species (SS) as biological pollution indicators. From physicochemical parameters: pH ranged from, 4.8 - 7.9; EC, 13.4 - 1634 μS/cm; Temperature, 26?C - 36.1?C and TDS, 17.42 - 1094.78 mg/L. Groundwater of Abuja FCT is not suitable for drinking as the species had the following concentration and percentages above the permissible limits for drinking water: TC (0 - 1280) 51.06%, FC (0 - 170) 19.15%, TBD (0 - 86.6) 98.94%, TBC (0 - 5120) 95.74%, CB (0 - 438) 74.47% and SS (0 - 223) 69.15%. Groundwater from Abuja FCT Granite-Gneiss fractured rock aquiferous formation is unfit for human consumption and an added danger to humans since it is usually assumed to be safe. Groundwater from Granite-Gneiss fractured rock aquifers could be the source of endemic outbreaks of waterborne diseases such as E. coli, Cholera, Gastroenteritis, Typhoid and Diarrhea; as such all groundwater from the aquiferous formations in Abuja FCT should be treated before consumption and use. Source protection strategies as well as monitoring are recommended although it may not serve the purpose for which it is intended since the potential for pollution is point and non-point sourced.
Overview on the Studies of Nitrate Pollution in Groundwater
地下水硝酸盐污染研究综述

CHEN Jianyao,WANG Ya,ZHANG Hongbo,ZHAO Xinfeng,
陈建耀
,王亚,张洪波,赵新峰

地理科学进展 , 2006,
Abstract: More than 90 papers of the last 20 years on nitrate pollution in groundwater were reviewed, and the issue both in China and abroad was found focusing on the following aspects: the transform processes and mechanism of nitrate in groundwater, the form of pollution and the sources of nitrate, and the methods to avoid and treat nitrate pollution. The transform processes include: mineralization-immobilization, fixation, nitrification and denitrification. All kinds of nitrate are classified into point origin and area origin. There are two approaches, structural ap-proache and non-structural approache, reported to deal with nitrate pollution in groundwater. The structural approach was well reported to dispose of nitrate in a local or point scale, while the non-structural approach could be adopted in the regional scale, but few case studies were reported. Techniques to treat nitrate pollution were well reported in China, e.g. carbon dioxide regenerated ion exchanger, bio-film-electrode process, etc. Nitrate pollution in groundwater is closely related to human activities, and the main sources of nitrate were identified as excessive application of commercial fertilizers, manure, and the irrigation by non-treated wastewater, etc. The main factors affecting the occurrence, distribution and change of nitrate in groundwater were identified as: Dramatic increasing in population that requires much more food supply, Urbanization that discharges too much waste to be absorbed by soil and water bodies, Over use of fertilizer, Poor management in water and land resources, Land use and land cover change, Public concern and policy issues, Change in global food production and trade Three themes were thus proposed for further study in nitrate, given as follows: 1. Integration of nitrogen and water cycle and processes, with respect to nitrogen aspects of hydrological cycle (NAHC); 2. Interface processes and mechanism regarding nitrate transformation in soil, plant, atmosphere and groundwater; 3. Impacts of nitrate in groundwater in the interaction of land and ocean, and assessment of human activities, such as urbanization, food production and trade, on the change of nitrate in groundwater in the global perspective.
Groundwater nitrate pollution in Souss-Massa basin (south-west Morocco)
T Tagma, Y Hsissou, L Bouchaou, L Bouragba, S Boutaleb
African Journal of Environmental Science and Technology , 2009,
Abstract: The objective of our study was to determine the current status of alluvial aquifer in the Souss-Massa basin, where the nitrate pollution of groundwater is being increasing along the last decades. A multiapproach methodology using hydrogeology, nitrate concentrations, irrigation type and oxygen-18 and deuterium data, was carried out to identify the sources of this pollution. According to the spatial distribution of nitrate contents, nitrate pollution occurs mainly in Chtouka-Massa plain. More than 36% of the sampled wells exceed the value of 50 mg/L as NO3 -. Groundwater in Souss plain is less polluted comparing it to Chtouka-Massa; only 7% of wells exceed the permitted level. Agricultural practices in the study sites are the main cause of serious nitrate pollution given the uperimposition of high nitrate concentrations with the distribution of irrigated perimeters. High nitrate levels are associated with high 18O values, clearly indicating that significant quantities of evaporated irrigation waters infiltrate along with fertilizer nitrate to groundwater system. Different 18O-NO3 - trends suggest isotopically distinct, non-point source origins which vary spatially and temporally, due to different degrees of evaporation/recharge and amounts of fertilizer applied.
Forecasting the e ects of EU policy measures on the nitrate pollution of groundwater and surface waters

Ralf Kunkel,Peter Kreins,Bjrn Tetzlaff,Frank Wendland,

环境科学学报(英文版) , 2010,
Abstract: We used the interdisciplinary model network REGFLUD to predict the actual mean nitrate concentration in percolation water at the scale of the Weser river basin (Germany) using an area di erentiated (100 m 100 m) approach. REGFLUD combines the agro-economic model RAUMIS for estimating nitrogen surpluses and the hydrological models GROWA/DENUZ for assessing the nitrate leaching from the soil. For areas showing predicted nitrate concentrations in percolation water above the European Union (EU) groundwater quality standard of 50 mg NO3-N/L, e ective agri-environmental reduction measures need to be derived and implemented to improve groundwater and surface water quality by 2015. The e ects of already implemented agricultural policy are quantified by a baseline scenario projecting the N-surpluses from agricultural sector to 2015. The REGFLUD model is used to estimate the e ects of this scenario concerning groundwater and surface water pollution by nitrate. From the results of the model analysis the needs for additional measures can be derived in terms of required additional N-surplus reduction and in terms of regional prioritization of measures. Research work will therefore directly support the implementation of the Water Framework Directive of the European Union in the Weser basin.
Nitrate Pollution in Groundwater for Drinking and Its Affecting Factors in Hailun,Northeast China
东北海伦地区农村地下饮用水硝态氮污染特征及其影响因素分析

ZHAO Xin-feng,YANG Li-rong,SHI Qian,MA Yan,ZHANG Yan-yan,CHEN Li-ding,ZHENG Hai-feng,
赵新峰
,杨丽蓉,施茜,马岩,张燕燕,陈利顶,郑海峰

环境科学 , 2008,
Abstract: Nitrate pollution in groundwater has become a worldwide problem. It may affect the water quality for daily use and thus the health of people. The temporal and spatial characteristics of nitrate pollution in the groundwater were addressed by sample analysis of the drinkable water from 157 wells in Hailun, Heilongjiang, northeastern China. It was found that the mean value of nitrate concentration in all wells was 14.01 mg·L-1. Of all the samples, the nitrate concentrations of 26.11% wells exceeded the standard of drinkable water (10.00 mg·L-1). A significant difference was found on the spatial distribution of nitrate pollution in the study area. The pollution degree in term of nitrate pollution was in the order: the central rolling hills and flooding plain > the northeastern mountain area > the southwest rolling hills and plain. Based on the results, the factors causing the pollution we analyzed from the well properties and pollution sources. As for well properties, the type of the pipe material plays a critical role in the groundwater nitrate pollution. It was found that the wells with seamless pipe have less pollution than those with multiple-sections pipe. The concentrations of seamless pipe wells and multiple ones were respectively 5.08 mg·L-1 and 32.57 mg·L-1, 12.26% and 82.35% of these two kinds wells exceeded 10.00 mg·L-1, the state drinking water standard. In the whole Hailun, there is no statistically relationship between nitrate-N levels of wells and the well depth. However, a statistically lower nitrate-N was observed in the deep wells than that in the shallower ones. The mean values of nitrate concentration of the seamless-pipe deep wells, seamless-pipe shallow wells, multiple-section-pipe deep wells and multiple-section-pipe shallow wells were 1.84, 12.02, 25.14 and 45.61 mg·L-1. Analysis of pollution source shows that the heavily polluted regions are usually associated with large use of nitrogen fertilizer and household livestock or poultry. This indicates a positive correlation between the nitrate-N pollution of groundwater and the nitrogen fertilizer, household livestock, poultry.
Nitrate Concentration in Groundwater in Isfahan Province  [cached]
A. Jafari Malekabadi,M. Afyuni,S. F. Mousavi,A. Khosravi
Journal of Science and Technology of Agriculture and Natural Resources , 2004,
Abstract: In recent decades, the use of nitrogen fertilizers has increased irrespective of their effects on soil properties, agricultural products and, particularly, on environmental pollution. Nitrate easily leaches from soils into groundwater. The objective of this study was to determine temporal and spatial nitrate concentrations in groundwater in agricultural, industrial and urban regions in some parts of Isfahan Province. Water samples were collected monthly from 75 agricultural, industrial, and urban wells of Isfahan, Najaf-abad, Shahreza, Natanz and Kashan during January-May 2001. The results indicated that NO3-N concentrations in most of the regions studied were higher than the standard level (10 mg/l) and nitrate pollution must be reckoned among the most serious problems of sustainable agriculture and exploitation of groundwater resources. Average NO3-N concentration in different wells ranged from 1.03 to 50.78 mg/l (4.64 to 228.5 mg/l as nitrate). The average NO3-N concentration in groundwater of Najaf-abad, Shahreza, Isfahan and Natanz-Kashan was 17.56, 14.6, 16.04, and 8.24 mg/l and 95.5, 100, 84 and 33.3 % of total wells in these regions had nitrate concentrations above the standard level, respectively. Maximum NO3-N concentration was detected in the agricultural region south of Najaf-abad (64.6 mg/l). Nitrate pollution in most of the sampling areas was mainly linked to agricultural activities. The average NO3-N concentration in groundwater of all agricultural, industrial, and urban regions, except for urban regions of Natanz and Kashan, were above the standard level. Generally, nitrate concentration level in groundwater increased with time and was maximum in March and April.
Groundwater chemistry and quality of Nigeria: A status review
A Edet, Tn Nganje, AJ Ukpong, AS Ekwere
African Journal of Environmental Science and Technology , 2011,
Abstract: The present work is a review on the quality characteristics of groundwater in Nigeria. The aim was to collate, synthesize and analyse hydrochemical data from available literature in order to evaluate the physical and chemical character, quality and determine the sources of ions. The review process covered four major groundwater sedimentary basins viz Benin, Benue, Niger Delta, Sokoto and the Crystalline Basement Complexes. The issue of saline groundwater in parts of Benue and Niger Delta Basins were given attention. In general, data show that on the average, TDS for the groundwater from the different basins was < 250 mg/l compared to the saline groundwater with average TDS as high as 15700 mg/l. The high salinity was attributed to dissolution of salts and seawater intrusion. Nitrate concentration on the average is high especially, for Sokoto Basin indicating anthropogenic pollution. Descriptive and multivariate statistics together with cross plots indicate that the major geologic controls on the groundwater chemistry are chloride dissolution, weathering (silicate and carbonate) and ion exchange. With respect to agricultural and irrigation purposes, the groundwater are excellent besides the water from the saline groundwater from Benue Basin and the coastal aquifers.
The Source of Arsenic and Nitrate in Borrego Valley Groundwater Aquifer  [PDF]
Mohammad Hassan Rezaie-Boroon, Jessica Chaney, Bradley Bowers
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.617145
Abstract: Groundwater in California is very precious, yet what we can withdraw is often contaminated with natural and anthropogenic pollution sources. We have examined the Borrego Valley (BV) groundwater (N = 6 wells) in southern California to understand the source of arsenic and nitrate in some of its groundwater production wells. The results show that the arsenic values range from <2 ppb to 12.2 ppb and the nitrate values from <1 ppm to 10.2 ppm for different wells respectively. The results showed that the arsenic concentration increased 270% for the well # ID1-10 since 2004 and showed an increase of 63% since 2013 respectively. For other wells the results showed an increase of 147% and 72% since 2001. The nitrate concentration has jumped 42% in concentration since last year in one of the wells. The objective of this study is to understand the nature and source of arsenic and nitrate in BV groundwater aquifer as to how this change in arsenic and nitrate concentration occurs through the time. The arsenic retention in the sediments is highly variable and controlled by local processes as a result of natural weathering process of metamorphic bedrock. The second results from the development of strongly reducing conditions at near-neutral pH values, leading to the desorption of arsenic from mineral oxides and to the reductive dissolution of Fe and Mn oxides, also leading to arsenic release. The high arsenic concentrations in some groundwater wells in Borrego Valley CA require the need for reconnaissance surveys in mineralized areas of fractured crystalline basement. Net groundwater extraction values are based on an irrigation efficiency of 78 percent with 14 to 22 percent irrigation return. We believe that the return flow from irrigational activity could be one of the major sources of nitrate transferring the agricultural contaminants such as nitrate to Borrego Valley aquifer.
天津市地下水硝酸盐污染现状与年际变化规律研究
Study on Nitrate Pollution in Groundwater and Interannual Change Regulation in Tianjin
 [PDF]

李明悦, 廉晓娟, 朱静华, 高贤彪
Advances in Environmental Protection (AEP) , 2013, DOI: 10.12677/AEP.2013.33015
Abstract:
硝酸盐含量是衡量地下水水质的重要指标,直接关系到人类的健康。为了摸清天津市地下水硝酸盐污染现状,2005~2008年连续8年对天津市地下水进行了取样调查及硝酸盐含量监测,对地下水硝酸盐污染现状及年际变化规律进行了分析研究。结果表明,天津市地下水\"\"含量总体较低,平均值为6.82 mg/L,其中约14.98%的地下水样超过WHO饮用水标准,约10.84%的地下水样超过我国地下水质量标准。地下水硝酸盐含量年际之间变化较大,总体表现为先降低后增加后又趋于平缓的趋势,由2005年的11.88 mg/L降至2007年的3.59 mg/L,而后逐渐升高至2012年的7.52 mg/L。不同监测时期地下水\"\"10 mg/L、20 mg/L超标率与相应时期地下水平均含量均呈极显著正相关。地下水\"\"平均含量每升高1 mg/L,10 mg/L、20 mg/L超标率分别提高1.90和1.67个百分点。
Nitrate content is an important index to evaluate the quality of groundwater which affects human health di-rectly. As to evaluate the nitrate contamination of groundwater in Tianjin, an eight-year, large-scale investigation and water-sampling analysis on nitrate concentration in Tianjin groundwater was performed from 2005 to 2008. At the same time, the nitrate pollution status and interannual change regulation were studied. The results showed that the average concentration of \"\" in groundwater was 6.82 mg/L, and about 14.98% samples exceeded the criterion of WHO drinking water quality, 10.84% samples exceeded the criterion of national drinking water quality. The interannual change of annual average concentration of \"\"has showed a trend which decreased firstly and then increased. The annual average concentration of \"\" has decreased from 11.88 mg/L in 2005 to 3.59 mg/L in 2007, and then increased to 7.52 mg/L in 2012 gradually. The over standard rate of 10
GIS-based Analysis of Spatio-temporal Variability of Groundwater Nitrate Concentration in High-yield Region in North China Plain
基于GIS的华北高产粮区地下水硝态氮含量时空变异特征

CHEN Shu-feng,LI Wei,HU Ke-lin,WU Wen-liang,CHU Zhao-hui,MAO Wen-feng,
陈淑峰
,李帷,胡克林,吴文良,褚兆辉,毛文峰

环境科学 , 2009,
Abstract: Nitrate pollution in groundwater is very widespread in intensive agricultural region. 394 samples from phreatic water wells and 283 samples from confined water wells were collected across Huantai County at the same season of 2002 and 2007, which is representative of high-yield region of North China Plain. The NO-3-N concentration was determined. Geostatistics combined with GIS technique were used to analyze the spatio-temporal variability of groundwater nitrate concentration. The average nitrate concentrations in phreatic water were 8.08 mg·L-1 and 14.68 mg·L-1 in 2002 and 2007 respectively, and that in confined water were 3.87 mg·L-1 and 7.19 mg·L-1 respectively. The spatial correlation distances of nitrate concentrations in confined water for both periods were greater than that in phreatic water. The mapping showed that the areas of phreatic groundwater with high levels of nitrate concentrations (10-15, 15-20, 20-30, and >30 mg·L-1) increased by 13.06%, 14.37%, 12.23%, and 3.85% from 2002 to 2007, while the area with low levels (0-5 and 5-10 mg·L-1) nitrate concentrations were decreased by 28.87% and 14.63% compared with 2002. However, the areas of confined water with nitrate concentrations of 5-10 mg·L-1, 10-15 mg·L-1and 15-20 mg·L-1 were increased by 28.01%, 9.33%, and 0.48% respectively, while the areas of NO-3-N concentration (0-5 mg·L-1) was decreased by 37.82%. The NO-3-N concentration in confined water was significantly negative related to groundwater depth for the two period, we found an increasing trend of NO-3-N concentration in the deeper confined water from 2002 to 2007.
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