Keywords

1 Introduction

In the past decades, the collection, conveyance and disposal of municipal solid waste (MSW) have become a crucial issue especially in major cities all over the world. Due to rapid urbanization, almost half of the world’s population was residing in cities and future projection shows that population may reach 5 billion by 2030 (Omar et al. 2012). The increase in population eventually increases the amount of waste generated in the major cities. In 2012, MSW generation in world cities is estimated to be 1.3 billion tonnes per annum, and it is expected to reach 2.2 billion tonnes per annum by 2025 (Hoornweg and Bhada-Tata 2012). The per capita MSW generation in developed countries and developing countries ranges from 522–759 and 109–526 kg per person per year (Karak et al. 2012). The MSW is usually collected from each home, academic institutions, offices and commercial complexes and is composed of organic materials (food waste, market waste, yard leaves, wood, etc.), plastic, glass, metals and other refuses (Albores et al. 2016). The quantity, composition and proportion of MSW vary from one part of the world to another. This variation in the composition depends on culture, location, climatic conditions, lifestyle, type of energy source and economic status. However, a study by Hoornweg and Bhada (Hoornweg and Bhada-Tata 2012) shows that in global scale, 46% consists of organic waste in MSW followed by paper (17%), plastic (10%), glass (5%) and metal (4%). In the same study, it is explained that OECD member countries have a low organic fraction of 27% when compared to East Asia and Pacific region countries which have a high organic fraction of 62%.

The cities are unable to manage increased MSW generation due to their lack of regulatory, financial, knowledge, institutional, and public participation. As a result of improper MSW management, degradation of the environment and human health effects occur. The major impacts could be contamination of soil, surface water, groundwater by heavy metals in the leachate (Xiaoli et al. 2007; Prechthai et al. 2008), toxic emissions while burning (McKay 2002), human health problems (Giusti 2009; Rovira et al. 2015) and methane emissions (Boeckx et al. 1996; Das et al. 2016). Hence by knowing these effects, there should be a proper MSW management for safe disposal of wastes. The management of waste involves the collection of waste, resource recovery and recycling, transportation and processing or disposal. Of these, the most important one is processing/disposal of waste (Reddy 2011). The common processing/disposal practices adopted in various countries are open burning, landfilling, composting, incineration and recycling or recovery from waste. Open burning and unsystematic landfilling are carried out widely in low-income and developing countries because they are very cheap–cum-rapid process. On the other hand, it will degrade the environment and affect human health, whereas, in developed countries systematic landfilling is carried out extensively. But for systematic landfilling, a vast land resource is required which is a major constraint in cities. In such places, incinerators are preferred which require less place and has the benefit of heat recovery and waste reduction by volume. If the MSW has high organic content, low calorific value and high moisture content (especially in low-income and developing countries) then incinerators will not be a suitable option. Those wastes which have high organic content are preferred for composting in which wastes are transformed into stabilized product. Only after the segregation of organic and inorganic wastes, the composting will become the alternative for the incinerator and landfill (Karak et al. 2012). Recycling and recovery of useful material from MSW at its source leads to waste reduction and recovery of valuable materials (Jha et al. 2011). A study by Lavee (2007) showed that reduction in direct cost up to 11% can be achieved when adopting recycling of MSW.

1.1 MSW Management in India

India is the second highest populated country (1.21 billion) in the world with annual urban population growth rate of 3.35%. In 2011 census, there are 7935 towns and it has increased by 2774 since 2001. The number of Class I towns were also increased from 394 to 468 which includes 53 million-plus cities. The Indian urban population has increased to 31.16% (377 million) in 2011 from 17.29% in 1951, and correspondingly rural population has come down to 68.84% in 2011 from 82.7% in 1951 (Census 2001 and 2011). The projection shows that by next 10 years nearly 50% of Indian population will reside in urban areas (Vij 2012). Activities associated with such population create solid waste in large quantity (Zhu et al. 2008). The solid waste includes solid or semi-solid domestic waste, agriculture, dairy waste, horticulture waste, commercial waste, sanitary waste, institutional waste, street sweepings, silt from the surface drains, catering and market waste and other non-residential wastes, treated biomedical waste (Solid Waste Management Rules 2016). In developing countries like India, the management of solid waste has become crucial since it is a major source of contamination of air, soil and water. The common activities involved in MSW management are waste generation, storage of waste in individual or community bins, waste collection, transport, processing and waste disposal. Generally, the waste generated in urban areas are of large quantities when compared to rural areas.

The wastes generated are collected separately as biodegradable and non-biodegradable waste. This segregation will help in the recovery of useful products for processing and eventually reduce the amount of waste to be handled. However, this segregation practice is not done properly by local authorities and individuals (Vij 2012). The collected wastes are stored in either movable or fixed bin. For transportation, movable bins are flexible while the fixed bins are time-consuming (Shekdar 2009). The stored wastes are transported to transfer station or taken directly to processing/disposal sites. The segregation step can also be carried out in the transfer station. In India, the waste management system rarely comprises the waste processing unit because of the cost involved in setting up of such units. Further, the unpredictable urban growth makes it more complex process. Without processing unit, the volume of waste to be dumped in landfills will be nearly equal to generated volume. In India, more than 90% of solid waste is disposed of unscientifically in landfills and open dump sites. Apart from landfilling, some of MSW disposal mechanisms such as composting, incineration, refuse-derived fuel and biomethanation are adopted (Sharholy et al. 2008; Kalyani and Pandey 2014).

To make the MSW management more effective in India, a revised and much-defined version of The Municipal Solid Wastes (Management & Handling) Rules, 2000, named Solid Waste Management Rules (SWMR) came into effect from April 2016. Some of the important highlights are discussed here. In SWMR, 2016, the jurisdiction is unfolded beyond municipal area to encompass outgrowths in agglomerated urban areas, notified industrial townships, census towns, areas under the control of Indian airports, railways, port and harbour, defence establishments, central and state government organizations, places of pilgrims, places of historical importance and special economic zones. The SWMR, 2016, gives priority in promoting waste to energy plant by (1) encouraging industries to use refuse-derived fuel, (2) non-recyclable combustible waste having calorific value of 1500 kcal/kg or more shall be utilized for generating energy through refuse-derived fuel, and (3) high calorific wastes shall be used for co-processing in cement or thermal power plants. The SWM Rules, 2016, mandate all local bodies for (1) setting up MSW processing facilities when the population is 1 lakh or more, (2) setting up common or stand-alone sanitary landfills and (3) carrying out bioremediation or capping of old and abandoned dump sites. It also provides specific criteria for site selection of sanitary landfills, setting up development facilities in landfill sites like MSW processing and its treatment facility, SWM in hilly areas, specifications for operation, closure of landfill and rehabilitation of old dump sites (Solid Waste Management Rules 2016).

1.2 MSW Generation in India

The Central Pollution Control Board estimated that 1, 41,064 tonnes of municipal solid waste was generated per day during 2014–2015. Of the total generated waste, 90% of wastes are collected by local bodies and only 34,752 tonnes of collected waste are treated. Maharashtra state generated highest MSW of 22,570 tonnes per day (TPD) followed by Uttar Pradesh (19,180 TPD) and Tamil Nadu (14,500 TPD) (Annual Status Report on Municipal Solid Waste Management 2014–2015). It is estimated that urban India will generate 2,76,342 TPD by 2021, 4,50,132 TPD by 2031 and 11,95,000 TPD of MSW by 2050 (Planning Commission’s Report of the Task Force on Waste to Energy 2014). Another estimate shows that MSW generation will reach 300MT by 2047 and about 169.6 km2 of land is required for disposal (Pappu et al. 2007; Management of Municipal Solid Waste 2010). The average per capita waste generation was found to be 0.11 kilograms per day (Mani and Singh 2016). The MSW composition at the source of generation and waste collection points was calculated on a wet weight basis, and it comprises 40–60% of organic fraction, 30–40% of ash and fine earth, 3–6% of paper and each less than 1% of plastic, glass and metals. The C/N ratio of MSW ranges from 20 to 30, and the calorific value ranges from 800 to 1000 kcal/kg (Sharholy et al. 2008; Gupta et al. 2015).

1.3 Environmental Issues of MSW

Almost all anthropogenic activities will have an impact on the environment and so MSW disposal. Even though proper waste management does reduce the magnitude of impact, it will not eliminate the impact totally. The assessment of the environmental impacts is important to protect environmental settings (Chandrappa and Das 2012). Groundwater is a substantial and invaluable resource for human beings. Groundwater contamination is accelerated after the establishment of industrial development and urbanization (Maiti et al. 2016). MSW unlined and lined landfills are considered to be primary sources of groundwater pollution due to the leachate migration from waste (Reyes-López et al. 2008; Sizirici and Tansel 2015). In India, most of the landfills do not have a barrier or leachate collection system to restrict the migration of leachate into groundwater (Naveen et al. 2016). Leachate is a complex mixture of pollutants having high biochemical oxygen demand, chemical oxygen demand, suspended particles, ammonium nitrogen and toxic characteristics (Kurakalva et al. 2016; Han et al. 2016; Fatta et al. 1999; Regadio et al. 2012). The leachate composition depends upon the nature of MSW, chemical and biochemical processes responsible for the decomposition of waste materials and total water content in waste (Naveen et al. 2016; Fatta et al. 1999). Therefore, groundwater contamination resulting from the landfill leachate shall be considered as a major environmental concern (Singh et al. 2008). Various studies have indicated that total dissolved solids, total hardness, organic matter, sodium, chloride and heavy metals are the important groundwater contaminants emanating from landfill leachate (Akinbile 2012; Smahi et al. 2013; Marzougui and Ben Mammou 2006). The major potential environmental effects associated with leachate are contamination of groundwater and surface water (Kjeldsen et al. 2002). Physicochemical and heavy metal parameters reported in the Indian literatures are presented in Table 1. Apart from leachate, MSW impacts include air pollution and global warming, fires and explosions, unpleasant odours, vegetation damage and landfill settlement (Shenbagarani 2013; Raman and Narayanan 2008).

Table 1 Physicochemical and heavy metal parameters reported in the Indian literature
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1.4 MSW in Vellore City

Vellore is a Sprawling city situated on the banks of River Palar in the north-eastern part of Tamil Nadu. Vellore City has an area of 87.91 km2 with a population of 5.02 lakhs. In the past 20 years, the normal rainfall per year ranges from 917 to 1030.3 mm. Vellore City has a semi-arid climate with very high temperature. Dry and hot weather exists throughout the year. The open dump site is located at the Saduperi village which is 5 km from Vellore City, and it has coordinates of 12° 90′N and 79° 09′E.

The area of open dump site is about 11 acres. For the past 50 years, MSW was dumped here. In dump site, segregation of organic and inorganic waste was not practised. Earlier manure preparation was done and now because of large proportion of plastics waste, separation of plastic process becomes tedious and manure production was stopped. MSW generation per head in Vellore City was 400 grams per day, and total solid waste dumped per day is of 200 tonnes. 563 sanitation workers are employed in Vellore Corporation. A total of 276 vehicles are engaged in sanitary works. With the help of these vehicles, only 150 tonnes of waste are collected daily. The ultimate analysis of Vellore MSW was done by Saravanan et al. (Saravanan and Bhagavanulu 2004), and it was represented in Fig. 1.

Fig. 1
figure 1

Weight percentage of components in Vellore MSW (Saravanan and Bhagavanulu 2004)

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2 Materials and Methodology

2.1 Sampling of Groundwater and Leachate

The sampling wells were identified in and around the solid waste dump site using a random sampling method with 3 km as the periphery. Twenty-two samples are collected for characterization. Of 22 samples, one is leachate sample and remaining 21 are groundwater samples. Within the stretch, we identified and collected 20 borewell samples and 1 open well sample. The open well was situated very closely to landfill. In 20 borewells, one well is situated inside landfill site and others are scattered in 3 km stretch (Table 2). The samples were collected once in 15 days for about six months and transferred to Environmental Laboratory at VIT University, Vellore. The leachate sample is collected from the leachate collecting pit at the dump site.

Table 2 Sampling locations in and around Saduperi MSW dump site
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2.2 Analytical Methods

The collected samples are taken to laboratory and are immediately stored at 4 °C. All groundwater samples were analysed for pH, total dissolved solids (TDS), electrical conductivity (EC), dissolved oxygen (DO), chemical oxygen demand (COD), turbidity, alkalinity, total hardness, calcium, magnesium, chloride, sulphate, nitrate, nitrite, potassium (K), sodium (Na), and heavy metals like nickel (Ni), cadmium (Cd) and chromium (Cr). The experimental analyses are carried out as per Bureau of Indian Standard and American Public Health Association Standard methods (Table 3).

Table 3 Details of measured parameters, its adopted methods and instruments used
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3 Results and Discussion

3.1 Leachate Characteristics

MSW composition, temperature, time, moisture and oxygen are the major factors influencing the quality of leachate (Naveen et al. 2017). Various physiochemical parameters of dump site leachate are presented in Table 4. In this study, leachate has pH value of 7.2, and it indicates the mature stage of dumping site (Jorstad et al. 2004), whereas pH values ranging from 6.9 to 9.8 are observed in similar studies (Raju 2012; Rathod et al. 2013; Shaikh et al. 2012). In MSW, organic matter is degraded to CO2 and NH3 and it further leads to the production of carbonic acid and ammonium ions. This carbonic acid is dissociated to form hydrogen cations and bicarbonate anions (Mahapatra et al. 2011).

Table 4 Dump site leachate characteristics
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BOD5 of leachate was 9100 mg/L and value of COD was 13,200 mg/L. This high level of BOD indicates the presence of organic matter in the leachate (Rathod et al. 2013). From the BOD and COD values, the BOD5/COD ratio was found to be 0.68. BOD and COD values are well correlated with (Rathod et al. 2013) and (Archana and Dutta 2014). The BOD5/COD ratio is the good indicator of leachate age. The young leachate (3–12 months) has BOD5/COD ratio of 0.6–1, followed by a medium leachate (1–5 years) of 0.30–0.60 and old leachate (greater than 5 years) of 0–0.30 (Alvarez-Vazquez et al. 2004). Hence, this dump sites leachate is found to be in young age. The young leachate is mainly composed of organic compounds that will not easily decompose and biodegrade. It also produces refractory compounds that are resistant to biochemical degradation (Agrawal et al. 2011; Abd El-Salam and Abu-Zuid 2015).

The concentration of TDS was recorded as 12,820 mg/L, and this extremely high value of TDS indicates the existence of inorganic materials. In the literature, TDS values ranges from 2027 to 81,000 mg/L (Agrawal et al. 2011; Rathod et al. 2013; Naveen et al. 2017; Jorstad et al. 2004; Bhalla et al. 2012; Aderemi et al. 2011). The chloride content of 5317.5 mg/L in leachate may be due to the mixing of domestic waste. The chloride content is well correlated with (Regadio et al. 2012; Jorstad et al. 2004) similar studies were done in the past. In leachate, the nitrogen cycle is dominated by microbial decomposition of organic carbon. As the time progresses, the nitrogen concentration decreases because of microbial utilization of nitrate compounds and denitrified as ammonia gas. Nitrate concentration was recorded as 4.12 mg/L, which is low in comparison to the reference values (Bhalla et al. 2012). In our study, chromium is abundant with a concentration of 2.84 mg/L.

The metallic elements such as nickel and cadmium are found to be 0.05 and 0.09 mg/L, respectively. Heavy metals concentration in landfills will be high in initial stages because the higher metal solubility is higher as a result of low pH (Kulikowska and Klimiuk 2008). The decrease in solubility of metal occurs in later stages, and a sharp decrease in heavy metal’s concentration is observed (Harmsen 1983). Na+ and K+ in the leachate are recorded with a concentration of 230 and 20.56 mg/L. These ions are not affected due to microbiological activities inside the dump site. Both Na+ and K+ are derived from domestic waste and vegetable residues (Christensen et al. 2001).

3.2 Groundwater Characteristics

Various physicochemical characteristics of leachate-contaminated groundwater samples are given in Tables 5 and 6. The collected groundwater samples were tested for pH and have an average value of 7.07 with 6.58 (GW-8) being the lowest and highest being 7.34 (GW-14). The least and the highest pH values are below the BIS standard values. In earlier studies, the pH of the leachate-contaminated groundwater varied between 4 and 8.16 (Rathod et al. 2013; Anilkumar et al. 2015; Alvarez-Vazquez et al. 2004; Lee et al. 2010; Moody and Townsend 2017; Banar et al. 2006). Dissolved gases and materials influence the pH of the water and shift it to alkaline or acidic side. Acidity in water is because of the presence of carbonic, fulvic, humic and organic acids (Mahapatra et al. 2011). The alkaline pH values can sustain with a high amount of dissolved substances and were good in supporting plant life.

Table 5 Physicochemical characteristics of leachate-contaminated groundwater samples
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Table 6 Minimum, maximum and average values of water quality parameters
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Total dissolved solids represent both dissolved and suspended matter in a water sample. All groundwater samples exceeded the permissible limit of 500 mg/L. The highest TDS values are recorded in GW-8 and GW-21 with a concentration of 9690 and 7620 mg/L, respectively. The very high TDS observed in the groundwater samples suggests percolation of leachate into groundwater and indicates the presence of inorganic materials (Mor et al. 2006). In the literature, TDS values of the groundwater ranges from 1440 to 25,514 mg/L (Bhalla et al. 2012; Alvarez-Vazquez et al. 2004; Kulikowska and Klimiuk 2008). High concentration of TDS makes water unpalatable and also causes irritation in gastrointestine in humans. Electrical conductivity (EC) indicates the presence of metals and amount of materials dissolved in water. The EC values in this study range from 757 to 6492 µS/cm. EC values up to 11,560 µS/cm are observed in the literature (Smahi et al. 2013). Except for GW-1 and GW-16, all groundwater samples exceeded the BIS limits which make them hard water and unfit for drinking. The highest values of calcium and magnesium hardness are 2050 and 5950 mg/L, respectively. Even the lowest hardness recorded in GW-16 (582.5 mg/L) is very close to BIS limit of 600 mg/L. By Piper plot (Fig. 2), calcium and magnesium are found to be major ions in groundwater sample. Hardness values from 1070 to 2890 mg/L are reported in the literature (Kulikowska and Klimiuk 2008; Harmsen 1983). Alkalinity is caused by the presence of carbonate, bicarbonate and hydroxide compounds.

Fig. 2
figure 2

Piper trilinear plot of major ions in the groundwater samples

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Dissolution of CO2 and carbonate minerals supplies bicarbonate into nearby groundwater. MSW in unlined dump site and oxidation of organic materials are the potential sources of alkalinity in groundwater (Mor et al. 2006). In present study the alkalinity concentration of the groundwater samples are recorded in the range of 660–2400 mg/L. The maximum value 2400 mg/L is 12 times higher than the desirable limit, i.e. 200 mg/L.

An excess of Cl− in water is usually taken as an index of pollution and considered to be a tracer for groundwater contamination (Loizidou and Kapetanios 1993). The range of chloride concentration is between 345.64 and 2153.39 mg/L. High concentration of chloride in groundwater is in correlation with leachate chloride concentration. The only source of anthropogenic contamination near sampling area is dump site indicating migration of leachate into groundwater. The chloride content, exceeding the concentration level of 250 mg/L, causes odour and taste problems.

Chemical oxygen demand (COD) is a measure of oxygen equivalent to the organic matter content of the water susceptible to oxidation by a strong chemical oxidant and thus is an index of organic pollution. Previous studies used COD as organic indicators to assess the groundwater pollution caused by the landfill (Mor et al. 2006). In this study, the average COD values of all samples are estimated to be 247 mg/L. Hence, it shows the strong correlation of organic matter in the leachate and shows the state of pollution level. Nitrate is a common contaminant of groundwater that originates from septic systems, manure storage and fertilizers. Nitrates, most highly oxidized form of nitrogen compounds, are the end product of the aerobic decomposition of organic nitrogenous matter (Moody and Townsend 2017; Al Sabahi et al. 2009). Nitrate concentration in samples was in the range between 0.01 and 1.32 mg/L which is within the standard limits.

As per World Health Organization (WHO), the concentration of potassium should be within 200 mg/L. Potassium is weakly hazardous in water, but it does spread pretty rapidly, because of its relatively high mobility and low transformation potential (Bali and Devi 2013). Potassium has been reported being an indication of the leachate effect, and their concentration in the sample is between 1.28 and 64.76 mg/L. All samples are within desirable limits. Maximum sulphate concentration was found in GW-2. The sulphate ion concentration in groundwater is due to the presence of domestic waste. In similar studies, maximum potassium and sulphate concentrations are 76 and 300 mg/L (Nagarajan et al. 2012).

Chromium in drinking water should be less than 0.05 mg/L. In most of the samples, the concentration is exceeding the standard value. Maximum concentration is found in sample GW-20 (1.1 mg/L), and lowest concentration is 0.2 mg/L in sample GW-3. Cadmium has a standard limit of 0.003 mg/L. In sample GW-21, the concentration is 0.05 mg/L which is highest. In the case of nickel, the maximum concentration observed was 0.48 which exceeds the standard limit.

3.3 Piper Plot

Piper plot represents the chemistry of water samples graphically. In general, we can classify the sample points in the piper diagram into six fields (Kumar 2013). They are as follows:

  1. (i)

    Ca–HCO3 type,

  2. (ii)

    Na–Cl type,

  3. (iii)

    Ca–Mg–Cl type,

  4. (iv)

    Ca–Na–HCO3 type,

  5. (v)

    Ca–Cl type,

  6. (vi)

    Na–HCO3 type.

Piper plot was created for collected samples using results obtained from analytical tests. Piper diagram consists of anion triangle, cation triangle and a diamond apex which shows combined plot of anions and cations.

Anions are plotted as a percentage of \( {{{\text{SO}}_{4}}^{2 - }},{ {\text{Cl}}^{-}}, {{{\text{HCO}}_{3}}^{-}} \; {\text{and}}\; {{{\text{CO}}_{3}}^{2 - }} \). Cations are plotted as a percentage of Na+, K+, Ca2+ and Mg2+ (Shenbagarani 2013). From the plot, it is concluded that most of the samples are in Ca–Mg–Cl and Ca–HCO3 type. Similar result was observed in the previous study (Nagarajan et al. 2012). This result indicates Ca2+, Mg2+ of cations and Cl−, \( {{{\text{HCO}}_{3}}^{ - }} \) of anions are dominant in water samples. It is well correlated with higher concentration of hardness and chlorides in groundwater samples.

3.4 Leachate Pollution Index (LPI)

Leachate pollution potential varies according to geographical area, and for comparing potentials of the different landfill site, 80 panellists were surveyed. The survey was conducted using multiple questionnaires to formulate LPI based on Rand Corporation’s Delphi Technique (Kumar and Alappat 2005). LPI is a number ranges from 5 to 100 that expresses the overall leachate contamination potential of a landfill based on several leachate pollution parameters at a given time. It is an increasing scale index, wherein a higher value indicates a poor environmental condition. The LPI can be used to report leachate pollution changes in a particular landfill over time (Mor et al. 2006; Umar et al. 2010). LPI can be used as an environmental monitoring tool and indicator for remedial measures. LPI depends on various parameters like m, P i , W i which represents the number of leachate pollutant parameters, the sub-index score of the ith leachate pollutant variable and the weight for the ith pollutant variable, respectively. The stepwise detail of formulation of LPI is presented in (Kumar and Alappat 2005).

3.5 Parameters Considered for LPI Calculation

In this study, the parameters available for calculating LPI are pH, TDS, COD, BOD, chlorides, chromium and nickel. LPI for these parameters are calculated in Tables 7 and 8. For calculation, the following formula was used.

Table 7 Leachate pollution index of Saduperi dump site sample
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Table 8 LPI calculation for standards (solid waste management rules)
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$$ {\text{LPI}} = \frac{{\mathop \sum \nolimits_{i = 1}^{m} w_{i} p_{i} }}{{\mathop \sum \nolimits_{i = 1}^{m} w_{i} }} $$

where

LPI:

Leachate pollution index

m :

Number of leachate pollutant parameters available

P i :

The sub-index score of the ith leachate pollutant variable

W i :

The weight for the ith pollutant variable

The sub-index scores of the ith leachate pollutant and the weight for the ith pollutant variable were taken from the literature (Bali and Devi 2013; Umar et al. 2010). LPI of leachate from Saduperi dump site was found to be 34.14 which is higher than untreated leachate in Jamalpur landfill site of Ludhiana City (Bhalla et al. 2014). LPI ranging from 19.5 to 45.01 was observed in previous studies (Bali and Devi 2013; Umar et al. 2010). The LPI calculation for standards given in municipal solid waste management and handling rules 2013 was also done. LPI value was found to be 7.88 for inland surface water disposal and 6.64 for land disposal. When compared with suggested LPI standards (7.88 and 6.64), the leachate from Saduperi dump site has high pollution potential with LPI of 34.14 and hence immediate remedial measures are recommended.

4 Conclusions

This work represents a real-time case study of MSW open dump site located at Saduperi, Vellore District, Tamil Nadu, India. Leachate and groundwater samples are collected in and around open dump site to analyse the possible impact of leachate on the quality of groundwater. Various physicochemical parameters and heavy metal concentration are carried out and reported. Results showed that leachate collected from dump site is of young age and has a high BOD, COD and TDS values. To quantify leachate pollution potential, LPI was calculated for standard concentration given in MSW rules and dump sites leachate. The LPI value was found to be four times greater than the corresponding standard LPI values. By this result, the leachate emanated from dump site should have contaminated nearby resources. The water quality analysis showed that wells situated near the dump site (e.g. GW-8) are highly contaminated than the wells that are far away. This is due to the fact that leachate being a viscous fluid is hindered due to the mass of solid soil matter. One of the significant findings is that the concentration of TDS, alkalinity and total hardness in most of the groundwater sample exceeds the BIS limits. The heavy metal concentrations present in the samples are found to have a potential threat to public health. Since there is no other source of contamination of wells, it is concluded that due to leachate from dump site groundwater has been contaminated. Proper management of dump site should be done to minimize the effect of leachate on groundwater. Engineered landfill sites should be provided with impermeable liner and drainage.