Pollution Index Method Research Articles

Geochemical baseline establishment and accumulation characteristics of soil heavy metals in Sabaochaqu watershed at the source of Yangtze River, Qinghai-Tibet Plateau

The establishment of soil geochemical baseline and heavy metal pollution assessment in the Qinghai-Tibet Plateau is of great significance for guiding environmental management in the high-cold and high-altitude regions. A total of 126 topsoil samples (0–20 cm) were collected and the contents of Cu, Pb, Zn, Ni, Cr, Cd, As and Hg were determined in the Sabaochaqu basin of the Tuotuo River, the source of the Yangtze River, in the Tibetan Plateau. The baseline values of 8 heavy metals were determined by mathematical statistics, iterative 2times standard deviation method, cumulative frequency and reference element standardization, and the soil heavy metal pollution in the study area was assessed by enrichment factor method and pollution index method. The results showed that the average contents of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were 31.84, 0.29, 66.07, 17.35, 0.021, 27.86, 49.35 and 88.56 mg/kg, respectively. Baseline values were 22.24, 0.217, 64.16, 15.69, 0.0191, 26.46, 34.91, and 68.62 mg/kg, respectively. There is a great difference between the baseline value of soil heavy metals in study area and the Xizang soil background value, especially the baseline value of Cd was 2.68 times of its background value. The results of the pollution evaluation based on the baseline values showed that the 8 heavy metals were slightly enriched, and the overall pollution status was light pollution, and measures should be taken to control and manage them. The research results can provide a reference value for the evaluation of soil heavy metal pollution in the source region of the Yangtze River, and also provide a theoretical basis for the construction of soil heavy metal baseline values in similar high-cold and high-altitude regions.

The new region demarcation framework for implementing the joint prevention and control of groundwater pollution: A case study in western of Bohai Bay, China

The joint groundwater pollution prevention and control (GPPC) strategy has been extensively implemented to address the coastal region groundwater pollution challenges in China. However, regional groundwater pollution control and treatment efficiency cannot achieve the expected results due to the lack of regional priority control orders and accurate restoration levels. Thus, this study developed a new region demarcation framework method for delineating GPPC zones, in tandem with a comprehensive pollution index method, the DRASTIC model, source apportionment. To validate the new methodological framework, a case study of groundwater pollution in Qinhuangdao, the western of Bohai Bay, China, was implemented to calculate pollution prevention and control zoning. In total, 340 groundwater samples from shallow aquifers with 9 target pollutants (NO3-, NO2-, NH4+, As, Cd, Cr, Cu, Pb, and Ni) were selected as the dataset for GPPC regionalization. The results showed that GPPC zoning further clarified the direction of groundwater pollution protection and management in Qinhuangdao. Compared to the traditional method, the new GPPC zoning better reflects groundwater mobility characteristics and pollution transport and enrichment patterns in terms of groundwater functional integrity and delineation. This new regional demarcation framework method contributes to providing support for the fine division of groundwater pollution zoning and precise pollution control for groundwater resource management in China.

Distribution Characteristics and Ecological Risk Assessment of Heavy Metals in Roadside Soil of Important National Highways on the Qinghai-Xizang Plateau

To clarify the impact of transportation on the sensitive and fragile ecosystems of the Qinghai Tibet Plateau and major ecological safety barrier functions, soil samples within 0-25 m on the roadside were collected from sections of national highways such as G214, G213, G345, G109, G316, and G317, and the contents of six heavy metals were analyzed. Then, the degree of heavy metal pollution and the risk of ecological hazards were evaluated using the single-factor pollution index method （Pi）, Nemero comprehensive index method （PN）, and potential ecological risk index method （RI）. The results showed that the heavy metal contents of As, Cd, Hg, Ni, Pb, and Zn in the soil of important transportation national roads on the Qinghai Tibet Plateau ranged from 5.65 to 176.00, 0.04 to 0.27, 0.01 to 0.14, 9.52 to 113.00, 9.16 to 54.50, and 24.70 to 109.00 mg·kg-1, respectively, showing high variability. In some sections of the soil, the values of the elements As, Cd, and Hg were higher than the local soil background values. The single-factor pollution index of heavy metals in roadside soil was Pi （As） > Pi （Hg） > Pi（Cd） > Pi （Pb） > Pi （Ni） > Pi （Zn）. The Nemero comprehensive pollution index ranged from 0.41 to 9.20, with an average value of 1.53, indicating clean and mild pollution. Some areas showed a moderate or severe pollution. The average potential ecological risk index of the research section was 106.2, and the soil was generally in a state of no pollution and light pollution. Only two road sections had soil heavy metal enrichment reaching moderate and strong ecological hazards. The comprehensive potential risk of the G213a road section indicated moderate to severe ecological risk, mainly contributed by Hg, As, and Cd. The comprehensive pollution risk of the G317 road section indicated mild to moderate ecological risk, mainly contributed by Hg and Cd. The heavy metal content in the soil of the Qinghai Tibet Plateau road area was not significantly correlated with the roadside distance and soil depth but was significantly positively correlated with the annual average temperature （P < 0.05）. In all, there was a trend of heavy metal input into the soil environment in areas with intense human activities and high traffic flow during road construction on the Qinghai Tibet Plateau.

Assessment and Source Analysis of Heavy Metal Pollution in Farmland Soil Around Tin Mine

Studying the status and source analysis of heavy metal pollution in farmland in typical mining and processing areas is an important prerequisite for promoting farmland soil ecological restoration and farmland protection in concentrated mining areas. In this study, the heavy metal content of farmland soil around a mining area in southwest China was detected, and the pollution status, distribution law, health risks, and sources of heavy metals were studied by using the land accumulation index method, comprehensive pollution index method, kriging interpolation method, health risk assessment method, and PMF receptor model on the sampling data. The results showed that the mean values of eight heavy metals in farmland soil except Ni exceeded the local soil background values, and the results of the ground accumulation index evaluation showed that Cd and Hg were extremely polluted； Pb and As showed medium pollution-heavy pollution； and Cr, Zn, Ni, and Cu were lightly polluted. In the health risk assessment, oral ingestion was the main exposure route posing a health risk to the human body； the main element that constituted non-carcinogenic health risks was As, and the carcinogenic risks were from As and Cd. PMF model analysis showed that the contribution rate of weathering natural sources of iron-bearing ore was 28.02%, and the main factors were Ca and Fe. The contribution rate of agricultural sources was 3.02%, and the main factors were Pb and As. The contribution rate of industrial and atmospheric deposition composite sources was 33.09%, and the main factor was Hg. The contribution rate of the parent material source was 17.27%, and the main factor was Ca. The contribution rate of mining activities such as mining and smelting was 18.60%, and the main factors were Zn and Cd.

Vertical Distribution Characteristics and Ecological Risk Assessment of Mercury and Arsenic in Ice, Water, and Sediment at a Cold-Arid Lake.

Mercury and arsenic are two highly toxic pollutants, and many researchers have explored the effects of the two substances on the environment. However, the research content of toxic substances in frozen periods is relatively small. To explore the spatial and vertical distribution of mercury and arsenic in the ice, water, and sediments of Wuliangsuhai Lake under ice conditions, and to assess the harm degree of the two toxic substances to human beings. We collected the ice, water, and sediments of the lake in December 2020, and tested the contents of Hg and As. The single-factor pollution index method, the local cumulative index method, and the ecological risk coding method were used to assess the pollution status in these three environmental media, and the Monte Carlo simulation combined with the quantitative model recommended by USEPA was used to assess the population health risk. The results showed that (1) The average single-factor pollution values of Hg and As in water were 0.367 and 0.114, both pollutants were at clean levels during the frozen period. (2) The mean Igeo values of Hg and As were 0.657 and -0.948. The bioavailability of Hg in the sediments of Wuliangsuhai Lake during the frozen period was high, and its average value was 7.8%, which belonged to the low-risk grade. The bioavailability of As ranged from 0.2% to 3.7%, with an average value of 1.3%. (3) Monte Carlo simulation results indicate acceptable levels of health risks in both water and ice. This study preliminarily investigated the distribution characteristics of toxic substances and their potential effects on human health in lakes in cold and arid regions during the frozen period. It not only clarified the pollution characteristics of lakes in cold and arid regions during the frozen period, but also provided beneficial supplements for the ecological protection of lake basins. This study lays a foundation for further environmental science research in the region in the future.

Analysis of The Effect of Floating Net Cages on Reservoir Water Quality

The use of Darma Waduk is as a source of clean water and a place of fish cultivation in the form of net cages. The number of floating net cages that currently exist is 6521, and the number continues to increase quite significantly from the previous year. The existence of floating net cages affects water quality, while water quality is an aspect to be considered in water utilization. The study aims to analyze the impact of floating net cages on water quality and efforts to control the floating net cage population in Darma Waduk. The research uses a quantitative and qualitative approach, starting with surveys and interviews with floating net cage farmers and related services. Subsequently, water samples were taken, and the results of laboratory tests were analyzed using the Pollution Index (IP) method. The results of the calculation using the pollution index (IP) method at the first point (PDAM Intake Area) obtained a result of 4.14, at the second point (around the floating net cage area of the village of Cipasung) a value of 3.76, and at the third point (in the floating net cage village of Jagara) a score of 4.12. The results of the research showed that the water quality taken from the three points of the sample included light pollution when referring to the class I water quality standard according to PP No. 22 for 2021. However, the presence of household and agricultural waste also contributes to the pollution burden in the Darma Valley.

Identification of the Heavy Metal Lead in the Industrial Area River in Buduran, Sidoarjo Regency using the Pollution Index Method

A river is an open channel that has the function of holding and flowing water from upstream to downstream and to the estuary. The Banjarkemantren River in Buduran District is located close to industrial areas. Pollution index and water quality status refers to the Decree of the Minister of Environment No. 115 of 2003. The highest pH at sampling points AI 3 and AI 4 was 7.9. The Pb content has the same results, namely 0.038 mg/L. This value does not exceed the quality standard limit based on Government Regulation No. 82 of 2001 concerning Water Quality Standards. Determined water quality status. using the Pollution Index method. The quality status of each sample is in "Good" condition (1.0 <Plj ≤ 5.0). The water quality status of the Banjarkemantren river is in the good category.

Evaluation of nitrate in shallow groundwater at Pasirkoja of Bandung City, Indonesia, using the pollution index and the nitrate pollution index methods

Pasirkoja is an old residential area in Bandung City currently densely populated. Some people in Pasirkoja use shallow groundwater for washing and bathing, and some for cooking. Pollutants very easily pollute shallow groundwater, and nitrate is one of the pollutants found in shallow groundwater in residential areas. The water quality status was determined using the pollution index (PI) method based on a Decree of the Minister of Environment Number 115 of 2003 and the nitrate pollution index (NPI) to ascertain the shallow groundwater quality in Pasirkoja of Bandung City, Indonesia. The variables used in the PI method were pH, turbidity, total dissolved solids (TDS), nitrate, and nitrite, while the NPI method used the nitrate parameter. Shallow groundwater samples were taken during the rainy season and dry season. Based on the PI method, the results showed that the quality status of shallow groundwater at the research location is mostly lightly polluted in the rainy and dry seasons. Meanwhile, based on the NPI method, most are clean (not polluted). Differences in the quality status of shallow groundwater depend on the environmental conditions around which shallow groundwater samples were taken. The research results also showed that, based on the PI method, nitrate is not the main parameter that determines pollution at the research location.

Bongso River Water Quality Status Due to Traditional Oil Mining Activities Using the Pollution Index Method

Traditional petroleum mining activities in 137 old wells in Wonocolo Village, Bojonegoro Regency Council District, East Java, have a positive impact on the local community's economy, but also have a negative impact on the environment in the form of pollution of surface water. The study aims to determine the quality of the Bongso River in the traditional Wonocolo petroleum mining area based on physical and chemical parameters (temperature, pH, DO, TSS, TDS, COD, phenol, and nitrate), as well as analyze the level of pollution in the river using the Pollution Index method. The results of the Bongso River water quality analysis contained parameters that exceeded quality standards, namely, SB 1 station with COD levels of 47.1 mg / L and Phenol 0.196 mg / L. SB 2 station with TDS levels of 1010 mg / L, TSS 93.60 mg / L, COD 94.0 mg / L and phenol 0.552 mg / L. SB 3 station TDS levels 1190 mg / L, TSS 1778 mg/L, COD 84.7 mg/L, and phenol 0.747. Station SB 4 levels TDS worth 1450 mg / L, TSS 1019 mg / L, COD 28.2 mg / L, phenol 0.632 mg / L and DO levels do not meet the minimum quality standards of 3.4 mg / L. Station SB 5 levels TDS 1310 mg / L, COD 103.5 mg / L and phenol 0.364 mg / L. Station SB 6 levels TDS 1400 mg / L, COD 65.9 mg/L and phenol 0.585 mg/L. Station SB 7 levels TDS 1230 mg/L, TSS 54.80 mg/L and phenol 0.556 mg/L. Salinity of the Bongso River increased from upstream (SB1) to middle (SB2); 0 ppt to 4 ppt (rainy season). Water quality status using the IP method shows that SB 1 and SB 5 stations are categorized as Lightly Polluted. Meanwhile, SB 2, SB 3, SB 4, SB 6, and SB 7 stations are categorized as Moderately Polluted.

Comparison between Pollution Index and STORET Methods in Determining Post-Mining Lake Water Quality in Lati Petangis Forest Park, Paser, East Kalimantan after Reclamation

Comparison between Pollution Index and STORET Methods in Determining Post-Mining Lake Water Quality in Lati Petangis Forest Park, Paser, East Kalimantan after Reclamation

Severe microplastic pollution risks in urban freshwater system post-landfill fire: A case study from Brahmapuram, India

To investigate the escalating issue of microplastic (MP), pollution in urban water bodies, this study focuses on the aftermath of the Brahmapuram landfill fire in Kochi, India, analyzing its impact on MP concentrations in nearby freshwater system. The study conducted sampling sessions at the landfill site immediately before and after the fire. Post-fire, findings demonstrated a substantial increase in MP concentrations in surface waters, with levels rising from an average 25793.33 to 44863.33 particles/m³, featuring a notable presence of larger, predominantly black MPs. Sediment samples showed no significant change in MP count, but there was a significant increase in mass concentration. SEM/EDS analysis revealed changes in surface morphology and elemental composition, suggesting thermal degradation. Risk assessment using the Microplastic Pollution Index (MPI) and Risk Quotient (RQ) methods indicated heightened MP pollution risk in surface water post-fire. Hierarchical cluster analysis revealed the landfill's proximity as a significant factor influencing MP characteristics in the aquatic system. The study highlights the escalated challenge of MP pollution in urban water bodies following environmental disasters like landfill fires, underscoring the urgent need for policy and environmental management strategies.

Study on Water Quality of Sekadau River Using Pollution Index Method

One of the leading causes of declining water quality is contamination from human activities. The Sekadau River serves as a primary water source for the residents of Sekadau Regency, facilitating bathing, laundry, kitchen equipment cleaning, and freshwater fish cultivation. The objective of this study is to evaluate the water quality of the Sekadau River, comparing it against Class II standards as stipulated in Government Regulation No. 22 of 2021 on Environmental Protection and Management. Subsequently, pollution levels in the Sekadau River at the measurement point were determined using the Pollution Index Method (PIM). The research findings reveal that the pollution index values for 2018, 2022, and 2023 fall within the lightly polluted category. Conversely, in 2019, the water quality of the Sekadau River exhibited improvement. It complied with water quality standards per the Minister of Environment and Forestry Decree No. 115 on Quality Status Determination Guidelines. Consequently, the Sekadau River remains suitable for bathing, laundry, freshwater fish cultivation, and other purposes requiring water of the same quality as its designated use. However, considering the increasing pollution trends in 2022 and 2023, appropriate measures are necessary to prevent the Sekadau River from becoming more polluted.

WATER QUALITY OF BATANG MERAO WATERSHED AND IMPLEMENTATION OF LANDSAT 8 OLI FOR THE TRANSPARENCY OF LAKE KERINCI WATERS

This research aims to analyse the water quality of the Batang Merao watershed and the implementation of the algorithm model from Landsat 8 Operational Land Imager (OLI) for the transparency of Lake Kerinci waters. The method used is descriptive quantitative, which is used to obtain measured data on water quality using the Pollution Index (PI) method based on the Decree of the State Minister for the Environment (KEPMENLH) No. 115/2003, PP No. 82/2001, and PP No. 22/2021, as well as the kriging method from an algorithm of the Landsat 8 OLI for total suspended solid (TSS) concentrations with the transparency of the waters of Lake Kerinci. Based on the test results of water samples in the Batang Merao DAS showed that several water quality parameters exceeded the Class II water quality standard PP No. 82/2001, which covers Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), and oil and fats parameters. The relationship between TSS concentration and water transparency of Kerinci Lake has a high coefficient of determination, reaching 0.8344; this indicates the transparency of Kerinci Lake is around 2 m or less. This means that the waters of Lake Kerinci have lower transparency.

ANALISIS KUALITAS AIR SUNGAI SAWUR SEBAGAI UPAYA PENGENDALIAN PENCEMARAN AIR DI KECAMATAN SAMBUNGMACAN KABUPATEN SRAGEN TAHUN 2023

Sawur River is a river that is the border of Central Java and East Java which has a brown to black color with a bit turbid so that it is polluted. This study aims to 1) identify the water pollution index in the Sawur River, Sambungmacan District, 2) examine efforts to control water pollution in the Sawur River, Sambungmacan District. Data analysis techniques using the pollution index method to determine the status of river pollution and SWOT analysis to formulate water pollution control efforts. Water samples were tested at 8 sample points and laboratory tests were carried out on nitrates, nitrites, ammonia, phosphates, potassium, detergent, and coliform. The results of the water quality laboratory show that there are several parameter elements that exceed the quality standards, namely nitrite, ammonia, and phosphate. The laboratory results are calculated by the pollution index formula, the pollution index is obtained at all points of the sample categorized as light pollution. According to the SWOT analysis, water pollution control efforts are in quadrant IV with a survival strategy. Efforts that can be made to control water quality over pollution are a) improve the provision of complete information, b) improve coordination between agencies on water pollution, c) increase inventory and identification of polluting sources, d) increase supervision of waste disposal, and e) increase public knowledge and participation for water quality control over pollution.

Geochemical characteristics and sources of heavy metal elements in the southern and western surface soils of Fengdu County, Chongqing

In order to explore the current situation and sources of heavy metal element pollution in the surface soil of the southern and western parts of Fengdu County, Chongqing. In this paper, the test and analysis results of 2955 surface soil samples collected from the project of "Chongqing Jiaoshi Dam Width, Liziwan Width, etc. a total of five 1:50,000 Land Quality Geological Survey" project were carried out. The single pollution index method and the land accumulation index method were used to evaluate the current status of heavy metal pollution in crops and soil. At the same time, correlation analysis and principal component analysis were performed. The results show that: (1) Compared with the soil heavy metal background in the Three Gorges Reservoir area, the average values of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in the study area are enriched to different degrees, except that the average content of Cr is lower than the background value. Among them, As, Cd and Hg elements were obviously enriched. (2) The calculation results of the single index of heavy metals in the surface soil showed that Cd pollution was the main in the area. Cu was only slightly to slightly polluted, and the number of lightly polluted samples accounted for only 0.07%. (3) The average Igeo trend of heavy metals in surface soil in the region was Cd>Hg>As>Pb>Zn>Cu>Ni>Cr. As, Pb, Zn, Cu, Ni and Cr were mainly non-slightly polluted. Cd and Hg elements were heavily polluted, but the sample accounted for a small proportion. The overall display area is dominated by Cd element pollution. (4) The source analysis results show that As, Cu, Pb, Ni, Zn and Cr in the study area are mainly derived from the earth's crust. Its content is related to the geological setting. The pollution of Hg and Cd is likely to be affected by human activities, mainly from atmospheric deposition.

Soil Mercury Pollution of Hainan Island, China: Patterns, Influencing Factors, and Health Risks

Due to the rapid expansion of tourism, mining, and manufacturing, the economy of Hainan Island in southern China has experienced swift growth. However, it also brings the risk of soil pollution by mercury (Hg) as a result of increased traffic and mineral processing activities. In order to investigate the characteristics of soil Hg pollution in Hainan Island and assess the health risk, a total of 239 samples were gathered from five representative regions across the island. The findings indicate considerable fluctuations in the soil Hg concentration across the five sub-study areas, which are influenced by factors such as wind direction, mining activities, and economic development. Changjiang Li Autonomous County, situated in the downwind direction (NW) and rich in mineral resources, shows the highest soil Hg concentration (10.00–1582.50 ng·g−1). Following closely are Haikou and Sanya, the two most economically developed cities on the island, with soil Hg concentrations of 8.33–321.50 ng·g−1 and 6.04–180.50 ng·g−1, respectively. Wuzhishan Nature Reserve and Lingshui Li Autonomous County, located in the upwind area (SE), show the lowest concentrations, ranging between 10.70–104.67 ng·g−1 and 9.43–84.00 ng·g−1, respectively. Both the Single Pollution Index method and the Geo-accumulation Index method were employed to assess the level of Hg pollution. The results indicate that nearly half of the sampling sites are contaminated, in which the proportion of contaminated sites in Sanya and Haikou are the highest, but the level of contamination is low; the heavily contaminated sites are predominantly found in Changjiang Li Autonomous County. However, the low Health Risk Index (HI) ranging from 0.0001 to 0.0334 suggests that although the soil is contaminated with Hg, it does not pose a substantial non-carcinogenic risk to human health.

Heavy Metal Pollution Status and Potential Ecological Risk Assessment in Farmland Surface Soil Along River in Jiaozuo Area

A total of 41 surface soil samples were collected from the farmlands along Guangliji River and Jianggou River in Jiaozuo area, and 7 heavy metals such As Cr, Cu, Zn, AS, Cd, Pb and Ni were determined by ICP-MS (Varian-820).The soil accumulation index method, single factor pollution index method, Nemerow comprehensive pollution index method and potential ecological risk index method were used to evaluate the pollution status and potential ecological risk of heavy metals in the study area. The results showed that compared with the risk screening value (pH>7.5) given in the "Soil Quality Standard for Soil Pollution Risk Control of Agricultural Land" (GB15618-2018), Cd in farmland soil along the two rivers exceeded the screening value by 5.7 times and 1.5 times, respectively, and was the main local pollutant. The Nemero comprehensive pollution index of the farmland along Guangliji River and Jianggou River was 9.71 and 1.88, respectively, which were in the level of heavy pollution and light pollution. The comprehensive potential ecological risk index of farmland along the two rivers is 417.65 and 85.79, with strong ecological risk and slight ecological risk respectively. The comprehensive evaluation shows that there is a certain degree of heavy metal pollution in the farmland soil along the river in Jiaozuo area, especially Cd pollution, and the ecological risk in some areas has exceeded the acceptable level, which should arouse the attention of the local government and relevant departments.

Status and risk assessment of heavy metal pollution in farmland soil in the southern suburbs of Jiaozuo City

A farmland in the southern suburb of Jiaozuo City was selected As the research area, 36 surface soil samples were collected, and the contents of heavy metals (Cd, Cr, Zn, Ni, Cu, Pb and As) in soil were determined. The ecological risk of heavy metals in soil was assessed by single factor pollution index method, Nemerow comprehensive pollution index method and potential ecological risk index method. The results showed that the average contents of Cd, Cr, Zn, Ni, Cu, Pb and As in the soil were 1.25, 62.96, 79.00, 28.91, 22.60, 11.02 and 42.25mg/kg, respectively. Cd and As in soil exceeded the standard, and the exceedance rate was 92.75% and 83.5%. The single factor pollution index was Cd>As>Cr>Zn>Cu>Ni>Pb from large to small, and Cd reached the moderate pollution level. The results of Nemerow comprehensive pollution index showed that Cd reached the level of severe pollution, and As was the level of severe pollution. The evaluation results of potential ecological risk index showed that Cd was at the moderate risk level, As was at the slight risk level, and other heavy metals were at the slight risk level. The comprehensive potential ecological risk index RI value was 13.87-266.80, which was at the slight to moderate risk level. Cd and As were the main risk sources of soil heavy metals, and their contribution rates to the comprehensive potential ecological risk index were 79% and 18%, respectively.

Effects of seasonal variation on the water quality of the Kadalundi river, India: evaluation of water quality indices, physicochemical and biological parameters

ABSTRACT The quality of the water depends on a variety of factors as it can contain both natural and manmade impurities. In this work, the water quality of the Kadalundi river, Kerala, India has been assessed with a special focus on the impact of seasonal variations . The quality of water for the entire year was analysed thoroughly collecting sixty water samples. The physicochemical parameters, such as turbidity, pH, total dissolved solids, total hardness, chlorides, iron, nitrate, dissolved oxygen, biochemical oxygen demand, and chemical oxygen demand, as well as bacteriological parameters (total coliforms and Escherichia coli), were evaluated as per the Indian standard methods, IS 3025. Each parameter was compared with the standard desirable limit prescribed by the Bureau of Indian Standards. The results were further examined with the weighted arithmetic water quality index and the Nemerow’s pollution index (NPI) methods. The study reveals that the overall water quality is very poor and hence proper treatment before use is recommended. According to the NPI, turbidity and iron are the most contributing parameters to the pollution of the river.

Evaluating the landfill leachate quality using leachate pollution index (LPI) and technique for order preference by similarity to an ideal solution (TOPSIS)

Variability and diversity of landfill leachate cause difficulties in assessing the actual degree of threat to the environment and selecting an appropriate method of disposal or treatment. Therefore, quantifying leachate contamination potential is essential in landfill management and could be used to assess the accuracy of landfill operation and its impact on surrounding areas. The aim of this paper was to evaluate the performance of the Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) method and its suitability in determining leachate pollution potential in comparison to the Leachate Pollution Index (LPI) method. For this purpose, the quality of leachate from the landfill, collected four times a year from 2004 to 2021, was analysed. The following parameters were monitored: pH, EC, Pb, Cu, Zn, Cr, and Hg. On the basis of the measured parameters, the LPI and TOPSIS indexes were calculated. The obtained results indicated that the TOPSIS method is more sensitive and accurate in observing changes in leachate quality. It can be applied to any number of contaminant parameters without restrictions on scope, quantity, or their relative importance. It can also be used to compare the variations in leachate quality over time or to analyse differences in leachate quality among various landfill sites.