Groundwater Vulnerability to Pollution in Kediri City, East Java Province, Indonesia

Groundwater is a water resource that is still a mainstay for humans. The need for groundwater increases with the growth of population and the development of the industrial and agricultural sectors. The residents of Kediri City still use wells from shallow aquifers to fulfill their water needs. Shallow aquifers are prone to pollution due to the influence of shallow groundwater depths and human activities. The purpose of this study is to determine the vulnerability of groundwater pollution in Kediri City. Groundwater vulnerability was conducted by the GOD method (Groundwater Occurrence, Overlaying Lithology, and Depth of Groundwater) that consists of 3 parameters, namely the groundwater confinement, the type of overlying strata, and the depth of the groundwater level. The analysis results show that the level of groundwater vulnerability according to the GOD method in Kediri City consists of moderate and high classes. The western and the eastern part of Kediri City is classified as a high level of vulnerability. In contrast, in the middle of Kediri City, it tends to experience a moderate level of vulnerability.

Integrated Assessment of Groundwater Potential Using Geospatial Techniques in Southern Africa: A Case Study in the Zambezi River Basin

Groundwater resources are largely used in rural communities of river basins due to their acceptable water quality and reliability for domestic purposes where little or no treatment is required. However, groundwater resources have been affected by changes in land use, mining activities, agricultural practices, industrial effluent, and urbanisation among anthropogenic influences while climate change impacts and volcanic eruptions have affected its involvement among the natural phenomena. The purpose of the study was to assess groundwater potential in the basin with the use of Analytical Hierarchy Process (AHP), remote sensing, GIS techniques, and groundwater occurrence and movement influencing factors. These factors were used to produce seven thematic maps, which were then assigned weights and scale using an AHP tool, based on their degree of influence on groundwater occurrence and movement. A weighted groundwater potential map was produced with four zones denoted as 0.4% (317 km2) for very good potential; 27% (19,170 km2) for good potential; 61% (43,961 km2) for moderate potential and 12% (8639 km2) for poor potential. Validation, using existing boreholes, showed that 89% were overlain on moderate to very good potential zones and henceforth considered to be a novel approach which is useful for groundwater resources assessment and integrated water management in the basin.

Analysis and Interpretation of Lineaments for Evaluation of Groundwater Potential in Shendam and Environs, North Central Nigeria

This study was done to evaluate the groundwater potentials of Shendam and environs using lineaments analysis. The trends of field joints were measured during mapping and using satellite remote sensing to generate lineament. The area is underlain by crystalline basement rocks of biotite granite, medium grain granite, and syenite. Assessment was carried out to depict the possibility of groundwater occurrence in the area. LANDSAT ETM+ imagery was used, together with the geological map to investigate areas favorable for groundwater development. This was achieved by plotting the lineament trends, superimposing the lineament on the geological map, superimposing the lineament on the drainage map, furthermore by plotting density map to know the groundwater potentials of the area. Lineament was used in drawing the respective rose diagrams for each rock type. Structurally, the area is characterized by a predominant NE to SW trend which also affects or controls drainage and groundwater occurrence with major groundwater recharge areas trending NE- SW of the study area. Analyses have shown that the study area has numerous fractures whose major trends are mainly in NE-SW directions. Lineament density maps shows the cross-cutting lineaments to be relatively high in the areas around the northeastern to southwestern parts of the study area but low in the other areas. Zones of high lineament intersection density are feasible zones for groundwater prospecting.

FEATURES OF ECOLOGICAL MONITORING OF SALINE SOILS OF THE STEPPE ZONE IN KHAKASSIA

The article deals with the results of the study of the biomass of soil microorganisms and the community of oribatid mites in the soils of lake territories in the steppe zone of the Republic of Khakassia. It is shown that the transformation of the zoo-microbial complex of chernozem-meadow soils of lake ecosystems in the process of salinization occurs along the path of reducing the microbiomass and metabolic activity (the microbiological part of the complex), the number and species richness (the zoological part of the complex). This transformation is related to the level of saline groundwater occurrence. The study demonstrated that the identified features of the studied soil biological indicators (respiratory activity of microbiomass and its metabolic coefficient, the number and species richness of oribatid mites) can be successfully used in the practice of monitoring ecosystems and soils located in the lake territories in the steppe zone of the Republic of Khakassia.

Development of monthly seawater intrusion vulnerability assessment method using GALDIT

Accurate diagnoses of vulnerability of seawater intrusion (SWI) into aquifers are required to ensure sustainable utilization of groundwater resources in coastal areas. GALDIT was selected to assess the SWI vulnerability on western coastal areas of South Korea. Climate change trends are updated every year. The existing GALDIT method has various scores to express the changing observed values. However, they are limited because of their sensitivity in the assessment of regional characteristics or climatic change due to low weight flexibility. Therefore, this study assessed vulnerability to SWI by classifying the existing GALDIT into static and dynamic parameters. The static parameters include groundwater occurrence (G), aquifer hydraulic conductivity (A), and distance from the shore (D), whereas the dynamic parameters include height to groundwater level above sea level (L), impact of existing status of seawater intrusion (I), and aquifer thickness (T). The monthly mean was used as the dynamic index to reflect monthly variations. To indicate the temporal trend of parameter L was calculated based on the data observed at the sea level station adjacent to the groundwater level station. To sensitively reflect the monthly changes in values, the range of scores was divided into 10 parts. The calculated GALDIT index showed that the most vulnerable month was September. In the progress of SWI, vulnerability was assessed monthly to highlight the differences in parameters that fluctuate seasonally. The proposed method can be used to apply intensive countermeasures to vulnerable sites and build an operation plan considering the vulnerability period.

Estimating the groundwater storage for future irrigation schemes

Presented in this paper is a feasibility study of groundwater for agricultural use (irrigation) in Northern Ghana. The study was conducted using Geo-electrical data, Boreholes drill logs, results of water quality, and results of the pumping test. The geo-electrical results were to unearth the lithology of the study area; it was found to be underlain with varying geology of both Precambrian and Paleozoic sedimentary formation. These formations consist of phyllite, schist, granite, meta-sediments, and meta-volcanics making up the Precambrian and sandstone, shale, siltstone, mudstones, granitiods also, of the Paleozoic sedimentary. Areas of low resistivity were targeted for drilling per the geophysical results of the profile, values between 24 and 100 ohm.m were zones of probable groundwater occurrence in the study. The groundwater storage capacity and the extractable storage capacity were estimated to be approximately 710,000 km3 and 290,000 km3. The pumping test results acquired from 81 boreholes from the study were used to analyze the sustainability and otherwise. However, groundwater depth was studied using the Static water level (SWL), areas of SWL around 22 m and 25 m are likely to have a shallow depth whereas areas of 17 m would have deeper groundwater depth.