| 1. |
- Abdullah, Twana, et al.
(författare)
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Assessing the Vulnerability of Groundwater to Pollution Using DRASTIC and VLDA Modelsin Halabja Saidsadiq Basin, NE, Iraq
- 2016
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Ingår i: Journal of Civil Engineering and Architecture. - USA : David Publishing Company. - 1934-7359 .- 1934-7367. ; 10:10, s. 1144-1159
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Tidskriftsartikel (refereegranskat)abstract
- Groundwater plays important roles as one of the essential source of water supplies of the studied area. Consequently, it needs to be prevented from contamination. In this study, two methods have been examined, namely DRASTIC (depth to groundwater, net recharge, aquifer media, soil map, topography, impact of vadose zone and hydraulic conductivity) and VLDA (vadose zone lithology, land use patterns, depth to groundwater and aquifer media) to model a map of groundwater vulnerability for contamination of the basin. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the VLDA model classified the area into four categories as well: low (2%), moderate (44%), high(53%) and very high (1%). The results demonstrate that there is a significant dissimilarity in the rate of vulnerability. Validation of the constructed maps is required to confirm the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration of two different seasons (dry and wet) was analyzed from (30) watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB (Halabja Saidsadiq Basin) is capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability level acquired using VLDA model is more sensible than that attained from the standard DRASTIC method .In addition, the DRASTIC models need to be modified based on the land use pattern, which clarifies the role of human activity on the vulnerability system.
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| 2. |
- Abdullah, Twana, et al.
(författare)
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Classification of groundwater based on irrigation water quality index and GIS in Halabja Saidsadiq basin, NE Iraq
- 2016
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Ingår i: Journal of Environmental Hydrology. - 1058-3912 .- 1996-7918. ; 24
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Tidskriftsartikel (refereegranskat)abstract
- Assessment of groundwater for irrigation purpose is proposed using the Irrigation Water Quality Index (IWQI) within the GIS environment. The model was applied to several aquifers in the study basin. Water samples were collected from thirty-nine sites from both water wells and springs from the dry season (September 2014) and the wet season (May 2015). Samples were tested chemically and physically for several variables: EC, Ca+2, Mg+2, Cl-, Na+ and HCO3- and SAR. The accuracy and precision methods were applied to find out the uncertainty of the chemical analysis results and its validity of application for the geochemical interpretations. Based on the spatial distribution of IWQI, the groundwater quality of HSB classified into several classes of both dry and wet seasons in terms of its restrictions on irrigation purposes. The classes include, Severe Restriction (SR), High Restriction (HR) and Moderate Restriction (MR). The coverage areas of all three classes are 1.4%, 52.4% and 46.2% for the dry season and 0.7%, 83.3% and16% for wet seasons respectively. The considerable variations in all these classes have been noted from dry to wet seasons, this might be related to increasing the aquifer recharges from precipitation and decreasing the aquifer discharges by the consumers in the wet season. Then the model was validated based on the relation between the aquifer recharge and spatial distribution of IWQI, the result of this validation confirmed the outcome of this study.
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| 3. |
- Abdullah, Twana, et al.
(författare)
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Groundwater Vulnerability Mapping Using Lineament Density on Standard DRASTIC Model : Case Study in Halabja Saidsadiq Basin, Kurdistan Region, Iraq
- 2015
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Ingår i: Engineering. - : Scientific Research Publishing, Inc.. - 1947-3931 .- 1947-394X. ; 7:10, s. 644-667
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Tidskriftsartikel (refereegranskat)abstract
- Groundwater is the most important source of water in the Halabja-Saidsadiq Basin. In this study, to generate a map of groundwater pollution vulnerability of the basin, the standard DRASTIC method has been applied. Due to the close relation between lineament density and groundwater flow and yield, the lineament density map was applied to the standard DRASTIC model in order to ensure accuracy towards the consideration of the effects of potential vulnerability to contamination. A lineament map is extracted from Enhanced Thematic Mapper plus (ETM+) satellite imagery using different techniques in remote sensing and GIS. The lineament density map illustrates that only six classes of lineament density can be identified ranged from (0 - 2.4). The lineament density map was rated and weighted and then converted to lineament index map. This index map is an additional parameter which was added to the standard DRASTIC model so as to map the modified DRASTIC vulnerability in HSB. The standard vulnerability map, classified the basin into four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). While the modified model classified the area into four categories as well: very low (28.75%), low (14.31%), moderate (46.91%) and high (10.04%). The results demonstrate that there is no significant variation in the rate of vulnerability. Therefore, the nitrate concentration between two different seasons (dry and wet) was analyzed from (30) water wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it confirmed that the HSB are capable to receive the contaminant because of suitability in terms of geological and hydrogeological conditions. Based on this verification, it could be claimed that the effect of lineament density is weak on the vulnerability system in HSB, because of its low density value.
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| 4. |
- Abdullah, Twana, et al.
(författare)
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Groundwater Vulnerability Using DRASTIC and COP Models : Case Study of Halabja Saidsadiq Basin, Iraq
- 2016
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Ingår i: Engineering. - USA : Scientific Research Publishing. - 1947-3931 .- 1947-394X. ; 8:11, s. 741-760
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Tidskriftsartikel (refereegranskat)abstract
- To avoid groundwater from contamination, the groundwater vulnerability tool can be examined. In this study, two methods were applied, namely: DRASTIC (Groundwater depth, Net recharge, Aquifer media, Soil map, Topography, Impact of vadose zone and Hydraulic Conductivity) and COP (Concentration of flow, Overlying layer and Precipitation) to model groundwater vulnerability to pollution. The result illustrated that four vulnerability classes were recognized based on both models including very low, low, moderate and high vulnerability classes. The coverage areas of each class are (34%, 13%, 48% and 5%) by DRASTIC model and (1%, 37%, 2% and 60%) by COP model, respectively. The notable dissimilarity between these two models was recognized. For this reason, nitrate elements were selected as a pollution indicator to validate the result. The concentrations of nitrate were recorded in two following seasons in (30) watering wells; as a result, the substantial variation was noted. This indicates that contaminants can be easily reached the groundwater due to its suitability in geological and hydrogeological conditions in terms of contaminant transportation. Based on this confirmation, the standard DRASTIC method becomes more sensible than COP method.
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| 5. |
- Abdullah, Twana, et al.
(författare)
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Hydrogeochemical Evaluation of Groundwater and Its Suitability for Domestic Uses in Halabja Saidsadiq Basin, Iraq
- 2019
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Ingår i: Water. - Switzerland : MDPI. - 2073-4441. ; 11:4
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Tidskriftsartikel (refereegranskat)abstract
- Evaluation of the hydrogeochemical characteristics and groundwater suitability for domestic use was conducted in the Halabja Saidsadiq Basin in the northeastern part of Iraq. The total studied area is about 1278 km 2 with a specific Mediterranean-type continental interior climate, which is cold in winter and hot in summer. To conduct the required laboratory chemical analysis for groundwater samples in the studied basin, 78 groundwater samples, in total, were collected from 39 water wells in the dry and wet seasons in 2014 and analyzed for major cations and anions, and the results were compared with the permitted limits for drinking water. An examination of the chemical concentrations of the World Health Organization drinking water norms demonstrate that a large portion of the groundwater samples is suitable for drinking, and a preponderance of groundwater samples situated in the class of hard and very hard water types for both seasons. Suitability of groundwater for drinking use was additionally assessed according to the water quality index classification. This showed that more than 98% of groundwater samples have good water quality in the dry and wet seasons. Conversely, the classification of groundwater samples based on Piper’s diagram designates that the groundwater type is alkaline water, with existing bicarbonate along with sulfate and chloride. However, water–ock exchange processes and groundwater flow have been responsible for the dominant water type of Ca–g–CO3.
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| 6. |
- Abdullah, Twana O., et al.
(författare)
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Vulnerability of groundwater to pollution using three different models in Halabja Saidsadiq basin, Iraq
- 2017
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Ingår i: European Water. - EU : E.W. Publications. - 1105-7580 .- 1792-085X. ; 57, s. 353-359, s. 1827-1834
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Tidskriftsartikel (refereegranskat)abstract
- Halabja Saidsadiq Basin (HSB) is one of a major basin of Iraq in terms of groundwater reservoirs. Intensive agricultural practices and economic revolution are widespread and located close to groundwater wells, which pose imminent threats to these resources. Therefore, the most effective and realistic solution is to prevent the contamination of groundwater through. The present study targets the computation of the vulnerability of groundwater reservoirs of the study area. Three methods have been examined, namely DRASTIC, VLDA and COP to model a map of groundwater vulnerability for contamination. The standard DRASTIC vulnerability maps classified the basin of four vulnerability index zones: very low (34%), low (13%), moderate (48%) and high (5%). The VLDA model also classified the area into four categories as well: low (2%), moderate (44%), high (53%) and very high (1%). Four vulnerability classes were recognized based on COP model including very low, low, moderate and high vulnerability classes with coverage areas of (1%, 37%, 2% and 60%) respectively. After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. Considerable variations in nitrate concentration on dry to wet seasons had been renowned. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability classes acquired using VLDA model is more sensible.
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| 7. |
- Abdullah, Twana, et al.
(författare)
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Possibility of Groundwater Pollution in Halabja Saidsadiq Hydrogeological Basin, Iraq Using Modified DRASTIC Model Based on AHP andTritium Isotopes
- 2018
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Ingår i: Geosciences. - : MDPI. - 2076-3263. ; 8:7
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Tidskriftsartikel (refereegranskat)abstract
- An anthropogenic activity is one of the most severe environmental causes for groundwatercontamination in the urban area. Groundwater thought to be one of the principal sources of water supply in Halabja Saidsadiq Basin, and therefore its vulnerability evaluation to define areas that are more vulnerable to pollution is incredibly vital. The objectives of this paper are to reveal weight modified of DRASTIC model based on the Analytical Hierarchical Process to estimate the proportional likelihood of groundwater resources pollution. Tritium isotopes analysis was chosen and applied as a pollution marker to confirm the result of this adjustment. Based on this modification, vulnerability classes that were achieved for the studied basin were alienated into five classes, including very low, low, medium, high, and very high, with vulnerability index value of (<100, >100–125, >125–150,>150–200, and >200), respectively.
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| 8. |
- Abdullah, Twana, et al.
(författare)
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Vulnerability of groundwater to pollution using VLDA model in Halabja Saidsadiq Basin, Iraq.
- 2016
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Ingår i: IWA Specialist Groundwater Conference. - Belgrade : Jaroslav Cerni Institute for the Development of Water Resources. - 9788682565468 ; , s. 72-75
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Konferensbidrag (refereegranskat)abstract
- Groundwater considered being the most vital source of water in several regions in the world. Specifically in the Halabja-Saidsadiq Basin, groundwater plays an important role as one of the essential source of water supplies. Therefore, it needs to be taken care of. In this study, VLDA method applied to model a map of groundwater vulnerability to contamination. The VLDA models classified the area into four categories with different coverage areas: low (2%), moderate (44%), high (53%) and very high (1%). After constructing every vulnerability map, it required to be confirmed in order to estimate the validity of the theoretical sympathetic of current hydrogeological conditions. In this study, nitrate concentration analysis was selected as a contamination indicator to validate the result. The nitrate concentration on two different seasons (dry and wet) was analyzed from (30) watering wells, considerable variations in nitrate concentration from dry to wet seasons had been noted. Consequently, it points toward that groundwater in the HSB are capable to receive the contaminant due to suitability of overlies strata in terms of geological and hydrogeological conditions. Based on this confirmation, the result exemplifies that the degree and distribution of vulnerability classes acquired using VLDA model is more sensible.
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| 9. |
- Abitew, Aymiro, et al.
(författare)
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Hydraulic conductivity of tailings deposit used as dam construction material at Aitik mine in Sweden
- 2013
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Konferensbidrag (refereegranskat)abstract
- Distribution of vertical and horizontal hydraulic conductivity and their correlation to geotechnical parameters affecting the hydraulic conductivity of tailings deposit at Aitik mine have been determined. The investigation was carried out along three sections which cover approximately 3km2 of area and 4-5meters of thickness. 3-5 test pits have been excavated in each section and samples are collected from various levels. The horizontal hydraulic conductivity has been found to have a good relation with fraction of fine particles in the deposit and void ratio. However, similar to the results of Jantzer et al (2008) from the same mine, the vertical hydraulic conductivity did not correspond to void ratio. According to evaluation of existing empirical relations to estimate hydraulic conductivity from particle size analysis, Hazen formula (1911) gives 25 and 45 times the measured values of vertical and horizontal hydraulic conductivity respectively. On the other hand, Chapuis et al (2003) has not been succeeded for prediction of hydraulic conductivity of undisturbed samples from the investigated area. However, it gives comparatively good prediction of hydraulic conductivity for disturbed samples which are compacted to their field dry density.
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| 10. |
- Abitew, Aymiro, et al.
(författare)
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Hydraulic conductivity of tailings sand used for dam construction at Aitik mine in Sweden
- 2012
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Ingår i: SWEMP 2012.
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Konferensbidrag (refereegranskat)abstract
- Distribution of vertical and horizontal hydraulic conductivity and their correlation to geotechnical parameters affecting the hydraulic conductivity of tailings deposit at Aitik mine have been determined. The investigation was carried out along three sections which cover approximately 3km2 of area and 4-5meters of thickness. 3-5 test pits have been excavated in each section and samples are collected from various levels. The horizontal hydraulic conductivity has been found to have a good relation with fraction of fine particles in the deposit and void ratio. However, similar to the results of Jantzer et al (2008) from the same mine, the vertical hydraulic conductivity did not correspond to void ratio. According to evaluation of existing empirical relations to estimate hydraulic conductivity from particle size analysis, Hazen formula (1911) gives 25 and 45 times the measured values of vertical and horizontal hydraulic conductivity respectively. On the other hand, Chapuis et al (2003) has not been succeeded for prediction of hydraulic conductivity of undisturbed samples from the investigated area. However, it gives comparatively good prediction of hydraulic conductivity for disturbed samples which are compacted to their field dry density.
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