IJISET - International Journal of Innovative Science, Engineering & Technology, Vol. 2 Issue 2, February 2015. www.ijiset.com ISSN 2348 – 7968 Quality of Ground Water in Aurangabad District (Maharashtra, India) using Geostatistical Method. Rahul Sagar Department of Computer Science, Vinayakrao Patil College, Vaijapur Aurangabad, Maharashtra, 423701, India Abstract pollution and losing of water sources have changed Groundwater is one of the major sources of water in exploitation policy of water and soil sources [3]. arid and semi -arid regions. Groundwater quality data In this research our aim is to estimate ground water and its spatial distribution are important for the purpose chemical quality using spatial interpolation techniques of planning and management. Geo-statistical methods several studies shown that interpolation technique are one of the most advanced techniques for accuracy is analyzed for soil & water properties. Several interpolation of groundwater quality. In this study, research shown that using kriging method to estimate kriging methods were used for predicting spatial spatial prediction of Groundwater to estimate one variable distribution of some groundwater quality parameters depends on variables type and regional factors which such as: pH, Alkalinity, salinity, dissolved influence this and any selected method for given region oxygen(DO), Biological oxygen cannot be generalized to others use of geo-statistics demand(BOD),Chloride(Cl), Sulphate method for analyzing Groundwater quality to estimate EC, (So4),Nitrate(No3), Calcium Hardness( CaH), CL, SO4, NO3, TDS has suitable accuracy to estimate Magnesium Hardness( MgH), and Total Hardness Groundwater quality [4, 5]. (TH). Data were collected from fixed eight (08) dug The present study was therefore, carried out with wells and bore wells in Aurangabad district the aim of spatial interpolation techniques for mapping (Maharashtra, India). Use of kriging method on our Groundwater chemical quality for Aurangabad district well sampling results provided valuable insight on the (Maharashtra), India. nature of the spatial and temporal variability of In Aurangabad district the chemical analysis groundwater quality parameters. results show that the ground water in the district is alkaline Keywords: Groundwater quality and interpolation DO, in nature, while the EC and TDS values show that the BOD, Geo-statistical methods, spatial distribution. ground water in the area is mineralized to medium extent. The concentrations of the major ions indicate that among 1. Introduction the cations, the concentration of magnesium ion is highest followed by calcium and sodium while among anions, the Everyone has to access to safe water & Sanitation. clean concentration of chloride ion is highest followed by drinking water has been given priority in the Constitution bicarbonate and sulphate ions. The results also show that of India, with Article 47 conferring the duty of providing the concentration of nitrate ions in the ground is clean drinking water and improving public health significant and appearing as major ion. standards to the State. The average availability of water is The geochemical classification of ground water reducing steadily with the growing population and it is in the area was carried to see the dominance of ions in estimated that by 2020 India will become a water stressed ground water. In the district, 08 samples were collected all nation. Groundwater is the major source of water in our representing the epm percentage of alkaline earths country with 85% of the population dependent on it [1, 2]. (Ca+Mg), alkali metals (Na+K), weak acids (CO3+HCO3) The knowledge of the occurrence, replenishment and and strong acids (CI+SO4NO3), in the ground water recovery of potable groundwater assumes special samples were calculated and samples were broadly significance in quality-deteriorated regions, because of classified into 2 classes as given in Table-1 As all the scarce presence of surface water. In addition to this, samples are from Basaltic aquifer, the type of water unfavorable climatic condition i.e. low rainfall with present in these samples should be of Ca-HCO3 type. But the perusal of Table-1 shows that 86% of samples are frequent occurrence of dry spells, high evaporation and having Ca-Cl type of water, indicating that the type of etc. on one hand and an unsuitable geological set up on the water in these samples has been changed from Ca-HCO3 other, a definite limit on the effectiveness of surface and type to Ca-Cl type. subsurface reservoirs During recent years, increasing 17 IJISET - International Journal of Innovative Science, Engineering & Technology, Vol. 2 Issue 2, February 2015. www.ijiset.com ISSN 2348 – 7968 This may be because of percolation of waste and wastewater containing high concentration of strong acid ions (CI+NO3+SO4) to ground water [6]. Table-1: Geochemical Classification of Ground Water Samples. Sr. Classification Type No. of % of No. Sampl Sample 1 Alkaline earths Ca- 02 14 (Ca+Mg > 50%) HCO3 exceeds alkali metals and weak acids (CO3+HCO3 > 50%) exceeds strong acids. Figure 1. Location map of Aurangabad district of Maharashtra (study 2 Alkaline earths Ca-Cl 06 86 area). (Ca+Mg > 50%) exceeds alkali metals and strong The district has been divided in 9 talukas viz., acids Aurangabad, Kannad, Soygaon, Sillod, Phulambri, (Cl+SO4+NO3 > Khuldabad, Vaijapur, Gangapur and Paithan talukas. The 50%) exceeds district has geographical area of 10,107 sq.km. Out of weak acids. which 814.15 sq.km is occupied by forest whereas 3 Total 08 100 cultivable area is 8135.57 sq.km and net area shown is 7150.55 sq.km in 2005-06. Agriculture is the main In this paper an attempt has been made to study the occupation of the rural people. Chemical quality of ground water collected from fixed Eight (08) dug wells and bore wells in Aurangabad district (Maharashtra) and its spatial distribution. Special 1.2 Hydrogeology of the Area Emphasis has been given to the chemical quality of the Well waters regarding their portability. The major part (95%) of the district constitutes a sequence of basaltic lava flows (Deccan Trap) while alluvium 1.1 Topography of the Study Area occupies a small portion. There are two distinct hydrogeological units in the district i.e. fissured Aurangabad district is situated in the north central part of formations (different units of basaltic lava flows) and Maharashtra between North Latitude 19° 15’ and 20° 40, porous formations (isolated patches of alluvial deposits). and East Longitude 74° 37’ and 75° 52’. It covers an area The occurrence and movement of ground water is of 10,107 sq. km falling in parts of Survey of India. The controlled by variation in water bearing properties of these district is bounded by Jalgaon district in north by Nasik formations. The depth to water levels in premonsoon district in West, Ahmadnagar and Beed districts in south Shallow water levels within 2 to 5 m bgl are seen in and Parbhani and Buldhana districts in east. The world northern parts of the district in parts of Soygaon and Sillod famous Ajanta and Ellora caves are situated in talukas. Water levels within 5 to 10 m bgl are seen almost Aurangabad district. There are also a few caves near in entire district occupying entire Khuldabad taluka and Aurangabad City. Other monuments of national fame are major parts of Aurangabad, Gangapur, Kannad and Sillod Bibi-ka-Maqbara and Daulatabad fort. (fig.1) talukas. Water levels in the range of 10 to 20 m bgl are seen in the form of 4-5 patches scattered in the district occupying major parts of Paithan and Vaijapur talukas and small parts of Aurangabad, Sillod and Kannad talukas. The depth to water levels during post monsoon ranges between 1.85 (Chauka) and 16.00 (Paithan). The spatial variation of the postmonsoon depth to water levels Shallow water within 5 m bgl are observed in north-south 18 IJISET - International Journal of Innovative Science, Engineering & Technology, Vol. 2 Issue 2, February 2015. www.ijiset.com ISSN 2348 – 7968 extended patch along eastern side of the district occupying distance h and is the random variable at location x . The i parts of soygaon, Kannad, Silod and Gangapur talukas and experimental variogram is fitted in theoretical model such almost entire Aurangabad taluka. water levels within 5 to as Spherical, Exponential, Linear or Gaussian to determine 10 m bgl are observed in major part of the district in three parameters, such as the nugget (c ), the sill (c) and western, southern and north eastern parts of the district, 0 the range (A ). These models are defined as follows [9]. occupying almost entire Vaijapur, Paithan, Kannad and 0 Sillod talukas and parts of Khuldabad and Gangapur talukas[6]. Spherical model: 2. Material and Methods Data Collected samples were analyzed in the laboratory to measure the concentration of the quality parameters. The water quality parameters along with the locations of the tube wells were used for spatial data analysis (SDA), development of semivariogram models and generation of spatial variability maps [7]. 2.1 Geostatistical Approach in Development of Spatial Variability Models For this paper to investigate the spatial correlation of the Aurangabad ground water data sets using Kriging methods And Kriged maps illustrate the spatial relationships. 2.2 Interpretation of Kriging Maps Spatial assessment of groundwater chemistry is important for revealing the correlation between location and the The total dissolved solids (TDS) parameter reflects the hydro chemical variables in the present study. ILWIS 3.7 level of minerals (such as carbonates, bicarbonates, software was used to determine kriged maps (Fig. 2 to 13) chlorides, sulfate, phosphate, silica, calcium, magnesium, [10, 11]. sodium, and potassium) that are present in water samples in dissolved form. The Average value of TDS values for Kriging is a general term describing a geo-statistical groundwater samples ranged between 449 to 545 approach for interpolation at un-sampled locations.