Landfill leachate affects metabolic responses of Zea mays L. seedlings

With an increasing focus on phyto-remediation options for landfill leachate, it is important to understand the responses of plant systems to landfill leachate stress. It is especially important to study the tolerant mechanisms of plant systems. We investigated several physiological changes of Zea mays L. (maize) in response to landfill leachate. Specifically, we investigated growth, chlorophyll content, lipid peroxidation, protein oxidation and activities of antioxidant enzymes. The results indicate that landfill leachate affected the growth and chlorophyll level of maize seedlings. Furthermore, landfill leachate elevated the levels of lipid peroxidation and protein oxidation in leaf tissues in a time-dependent manner, accompanied by the changes in antioxidant status. The physiological responses varied as a function of leachate concentration, and the growth inhibition, chlorophyll content inhibition and oxidative stress occurred after the exposure of higher concentrations of leachate. Higher concentrations of landfill leachate contained higher levels of pollutants. Our results indicate that landfill leachate affected the metabolic responses of plant systems. The risk of pollution occurred mainly in samples of higher concentration. Therefore, the critical aspect of phyto-remediation for landfill leachate is controlling its concentration. In doing so, plant systems may be able to tolerate the environmental stress of landfill leachate.     

Trends in the use of Fenton,electro-Fenton and photo-Fenton for the treatment of landfill leachate

Advanced oxidation processes (AOPs) such as Fenton, electro-Fenton and photo-Fenton have been applied effectively to remove refractory organics from landfill leachate. The Fenton reaction is based on the addition of hydrogen peroxide to the wastewater or leachate in the presence of ferrous salt as a catalyst. The use of this technique has proved to be one of the best compromises for landfill leachate treatment because of its environmental and economical advantages. Fenton process has been used successfully to mineralize wide range of organic constituents present in landfill leachate particularly those recalcitrant to biological degradation. The present study reviews the use of Fenton and related processes in terms of their increased application to landfill leachate. The effects of various operating parameters and their optimum ranges for maximum COD and color removal are reviewed with the conclusion that the Fenton and related processes are effective and competitive with other technologies for degradation of both raw and pre-treated landfill leachate.     

Batch tests on mineral deposit formation due to co-mingling of leachates derived from municipal solid wastes and waste-to-energy combustion residues

Deposit formation in leachate collection systems can be problematic for landfill operations. Deposits from municipal solid waste (MSW) derived leachates are impacted by microbial activity and biofilm development, whereas leachates generated from co-disposal of MSW with combustion residues (CR) from waste-to-energy (WTE) facilities and other mineral-rich waste materials are more prone to forming dense mineral deposits dominated by calcium carbonate. In this study, leachates from laboratory lysimeters containing either WTE-CR or shredded MSW were mixed at different volumetric ratios. The mixed leachates were incubated for 5 weeks in batch tests to evaluate the potential for formation of precipitates. Although mineral precipitates have been reported to form in landfills with no co-disposal practices, in this study mineral precipitates did not form in either the WTE-CR derived leachate or the MSW derived leachate, but formed in all leachate mixtures. Mineral precipitates consisted of calcium carbonate particles, with the highest yield from a 1:1 combination of the WTE-CR derived leachate mixed with the MSW derived leachate. The introduction of gaseous carbon dioxide or air into WTE-CR derived leachate resulted in the production of particles of similar chemical composition but different morphology. Operation of landfills to prevent co-mingling of mineral-rich leachates with microbially active leachates and/or to control leachate exposure to sources of carbon dioxide may help to prevent this type of precipitate formation in leachate collection systems.     

Projection of landfill stabilization period by time series analysis of leachate quality and transformation trends of VOCs

The purpose of this study was to evaluate suitability of using the time series analysis for selected leachate quantity and quality parameters to forecast the duration of post closure period of a closed landfill. Selected leachate quality parameters (i.e., sodium, chloride, iron, bicarbonate, total dissolved solids (TDS), and ammonium as N) and volatile organic compounds (VOCs) (i.e., vinyl chloride, 1,4-dichlorobenzene, chlorobenzene, benzene, toluene, ethyl benzene, xylenes, total BTEX) were analyzed by the time series multiplicative decomposition model to estimate the projected levels of the parameters. These parameters were selected based on their detection levels and consistency of detection in leachate samples. In addition, VOCs detected in leachate and their chemical transformations were considered in view of the decomposition stage of the landfill. Projected leachate quality trends were analyzed and compared with the maximum contaminant level (MCL) for the respective parameters. Conditions that lead to specific trends (i.e., increasing, decreasing, or steady) and interactions of leachate quality parameters were evaluated. Decreasing trends were projected for leachate quantity, concentrations of sodium, chloride, TDS, ammonia as N, vinyl chloride, 1,4-dichlorobenzene, benzene, toluene, ethyl benzene, xylenes, and total BTEX. Increasing trends were projected for concentrations of iron, bicarbonate, and chlorobenzene. Anaerobic conditions in landfill provide favorable conditions for corrosion of iron resulting in higher concentrations over time. Bicarbonate formation as a byproduct of bacterial respiration during waste decomposition and the lime rock cap system of the landfill contribute to the increasing levels of bicarbonate in leachate. Chlorobenzene is produced during anaerobic biodegradation of 1,4-dichlorobenzene, hence, the increasing trend of chlorobenzene may be due to the declining trend of 1,4-dichlorobenzene. The time series multiplicative decomposition model in general provides an adequate forecast for future planning purposes for the parameters monitored in leachate. The model projections for 1,4-dichlorobenzene were relatively less accurate in comparison to the projections for vinyl chloride and chlorobenzene. Based on the trends observed, future monitoring needs for the selected leachate parameters were identified.     

Behavior of endocrine-disrupting chemicals in leachate from MSW landfill sites in Japan

Endocrine-disrupting chemicals (EDCs) in landfill leachates and the effluent from leachate treatment facilities have been analyzed by many researchers. However, seasonal and yearly variations and the influence of landfill age are still not clear. In this study, leachate was sampled on four occasions each, at different seasons, from two MSW landfills which receive different waste material. Then, the quantities of alkylphenols (APs), bisphenol A (BPA), phthalic acid esters (PAEs) and organotin compounds (OTs) in leachate were determined. By sampling leachate from landfill cells of different age, the long-term behavior of EDCs was studied. Furthermore, leachate was also sampled at different points in the process of a leachate treatment system, and then the behavior of EDCs in the facility was studied. The concentrations of APs were as low as in surface waters, and OTs were not detected (detection limit was 0.01 microg/l), while BPA and DEHP, which were the most abundant of the four substances measured as PAEs, were found in all the leachates that were measured. Concentrations of BPA and DEHP were almost constant regardless of season, except for a couple of low concentrations observed for BPA. The varying composition of landfilled waste did not influence BPA and DEHP in leachate. Concentration of BPA in raw leachate tends to decrease as the years go by, but the concentration of DEHP was observed to remain at a constant level. BPA was considerably degraded by aeration for leachates from the two landfills, except when the leachate temperature was low. Aeration, coagulation/sedimentation, and biological treatment could not remove DEHP.     

Temporal variation of leachate quality from pre-sorted and baled municipal solid waste with high organic and moisture content

Landfill leachate characterization is a critical factor in establishing a corresponding effective management strategy or treatment process. However, it is often difficult to forecast leachate quality because of a variety of influencing factors such as waste composition and landfill operations. This paper describes leachate formation mechanisms, summarizes leachate quality indicators, and investigates the temporal variation of leachate quality from pre-sorted and baled municipal solid waste characterized with high organic and moisture content. The purpose of the study is to evaluate the potential effects of waste composition and site-specific operational procedures on biodegradation processes and leachate quality at a field-scale landfill that receives in excess of 1800 tonnes per day of refuse. For this purpose, waste disposal and leachate generation rates were monitored and leachate samples were collected for a period of 18 months during the early stages of refuse deposition. Chemical analysis was performed on the samples and the temporal variation of several parameters were monitored including pH, COD, TOC, TDS, chlorides, sulfates, orthophosphates, nitrates, ammonia nitrogen, hardness, and heavy metals. Chemical concentration levels were related to biological activity within the landfill and the results indicated that: (1) pre-sorting and baling of the waste did not hinder waste stabilization; and (2) the high organic and moisture contents resulted in an extremely strong leachate, particularly at the onset of biodegradation processes, which can affect the leachate treatment facility.     

Research on leachate recirculation from different types of landfills

Landfills can produce a great amount of leachate containing highly concentrated organic matter. This is especially true for the initial leachate from landfilled municipal solid wastes (MSW) that generally has concentrations of COD(Cr) and BOD(5) up to 80,000 and 50,000mg/L, respectively. The leachate could be disposed by means of recirculating technique, which decomposes the organics through the action of proliferating microorganisms and thereby purifies the leachate, and simultaneously accelerates organic decomposition through water saturation control. Data from experimental results indicated that leachate recirculating could reduce the organic concentration considerably, with a maximum reduction rate of COD(Cr) over 95%; and, using a semi-aerobic process, NH(3)-N concentration of treated leachate could be under 10mg/L. In addition, the organic concentration in MSW decreased greatly.     

Low-cost treatment of landfill leachate using peat

The EU Landfill Directive obliges member states to collect and treat leachate from landfill sites. In regions of high population density, this is commonly achieved through discharge of the leachate to the municipal sewerage system. In Ireland, rural landfills can be a long distance from a suitable sewerage system, resulting in high transportation costs. On-site treatment systems, when used elsewhere, are mainly aerobic treatment systems, which are costly to construct and operate. There is a particular need for low-cost, low-maintenance leachate treatment systems for small low-income landfills, and for closed landfills, where long-term running costs of aerobic systems may be unsustainable. In 1989, this research work was initiated to investigate the use of local peat for the treatment of leachate from a small rural landfill site. In 1997, following the award of grant-aid under the EU LIFE Programme, a full-scale leachate treatment plant was constructed, using local un-drained peat as the treatment medium. When the LIFE Project ended in February 2001, leachate treatment research continued at the site using a pre-treated peat as the treatment medium. The treatment levels achieved using both types of peat are discussed in this paper. It is concluded that landfill leachate may be successfully treated using a low-cost peat bed to achieve almost 100% removal of both BOD and ammonia.     

Clogging of finger drain systems in MSW landfills

A numerical model ‘BioClog’ is used to examine clogging of granular drainage material within finger drains at the base of landfills. The reduction in porosity of drainage material is evaluated as the accumulation of clog mass reduces the pore spaces of granular media. The leachate mounding within the landfills caused by the reduction in hydraulic conductivity of finger drain is modeled. The effect of overburden pressure on the engineering properties of waste material and consequent leachate mounding is considered. The calculated rates of leachate mound development for two landfills with finger drain leachate collection are shown to be in encouraging agreement with the observed data at the times when data were available. It is demonstrated that a significant leachate mound can be expected to develop over time when the leachate collection system is comprised of finger drains; however the rate of increase and the magnitude at a given time will depend on a number of factors including the grainsize, thickness and spacing of the finger drains, and the thickness of waste as well as the leachate generation rate.     

Evaluating biotoxicity variations of landfill leachate as penetrating through the soil column

Recent studies of leachate-induced ecotoxicity have focused on crude samples, while little attention has been given to changes in biotoxicity resulting from the environmental behavior of landfill leachate. Therefore, we set up a soil column to simulate the underground penetration of leachate into the soil layer, define the rules of migration and transformation of leachate pollutants, and determine the variation in toxicity of landfill leachate during penetration. The results demonstrated that: (1) landfill leachate inhibited the growth and chlorophyll levels, elevated the levels of lipid peroxidation and protein oxidation, and stimulated the antioxidant enzyme activities of barley seedlings. The effects generally displayed a peak value at 12–24 cm, slowly declined at 36–48 cm, and then rapidly decreased with penetrating distance in the column. (2) Statistical correlation analysis of the properties of leachate and the observed biotoxic effects revealed that COD, conductivity and heavy metals (esp. Ni, Mn, Cd) were positively correlated with variations in biotoxicity. (3) The microbial activity of outflowing leachate sampled from the 48 cm port was significantly higher than the activity from succedent ports, and the types of contaminants increased in the leachate outflowing from the same port, implying that microbial behaviors near the 48 cm port could be used to partially evaluate variations in the composition and biotoxicity of landfill leachate. Taken together, the above results illustrate the polluting characteristics of landfill leachate when penetrating a soil column and provide guidance for pollution control and risk assessment of landfill leachate.     

Environmental impact assessment of leachate recirculation in landfill of municipal solid waste by comparing with evaporation and discharge (EASEWASTE)

In some arid regions where landfill produces minimal amount of leachate, leachate recirculation is suggested as a cost-effective option. However, its long-term impacts to environment remain disputed. For the purpose of revealing the environmental impacts of leachate recirculation in landfill, four scenarios were modeled using EASEWASTE, comparing the strategies of leachate recirculation (with or without gas management), evaporation and discharge. In the current situation (Scenario A), a total of 280 t of waste was generated and then transported to a conventional landfill for disposal. A number of contaminants derived from waste can be stored in the landfill for long periods, with 11.69 person equivalent (PE) for stored ecotoxicity in water and 29.62 PE for stored ecotoxicity in soil, considered as potential risks of releasing to the environment someday. Meanwhile, impacts to ecotoxicity and human toxicity in surface water, and those to groundwater, present relatively low levels. In Scenario B, leachate evaporation in a collecting pool has minimal impacts on surface water. However, this strategy significantly impacts groundwater (1055.16 PE) because of the potential infiltration of leachate, with major contaminants of As, ammonia, and Cd. A number of ions, such as Cl^?, Mg²⁺, and Ca²⁺, may also contaminate groundwater. In Scenario C, the direct discharge of leachate to surface water may result in acidification (2.71 PE) and nutrient enrichment (2.88 PE), primarily attributed to soluble ammonia in leachate and the depositional ammonia from biogas. Moreover, the direct discharge of leachate may also result in ecotoxicity and human toxicity via water contaminated by heavy metals in leachate, with 3.96 PE and 11.64 PE respectively. The results also show that landfill gas is the main contributor to global warming and photochemical ozone formation due to methane emission. In Scenario D, landfill gas flaring was thus be modeled and proven to be efficient for reducing impacts by approximately 90% in most categories, like global warming, photochemical ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. Therefore, leachate recirculation is considered a cost-effective and environmentally viable solution for the current situation, and landfill gas treatment is urgently required. These results can provide important evidence for leachate and gas management of landfill in arid regions.     

Toxicological evaluation of the chemical oxidation methods for landfill stabilization

As the stabilization criteria for landfill sites, only chemical criteria for the leachate discharges from the landfill sites have been used in Japan and many other countries. Recently, chemical oxidation has been developed as a method for the early-stabilization of landfills. However, by-products that are difficult to detect by chemical analysis can be produced by this method. Therefore, toxicity tests are useful tools for detecting the changes of leachate quality after application of this method. The heat source in the A landfill was analyzed by organic position inquiry technology, and ozone-treated leachate was sprayed back to the heat source in the landfill. Toxicity changes of the leachate after the spray were monitored using Microtoxtrade mark, ToxScreen-II, and DaphTox tests. The hardly-degradable organic matter was efficiently removed and toxicities of the leachate in the heat source decreased after the application. These toxicity results were significantly related to chemical oxygen demand (COD) changes. Thus, it was concluded that the toxicity tests were effective for monitoring the leachate quality after applying the chemical oxidation method for landfill stabilization, and its incorporation to establish the criteria for early-stabilization of landfill sites needs to be considered.     

Electrochemical oxidation for landfill leachate treatment

This paper aims at providing an overview of electrochemical oxidation processes used for treatment of landfill leachate. The typical characteristics of landfill leachate are briefly reviewed, and the reactor designs used for electro-oxidation of leachate are summarized. Electrochemical oxidation can significantly reduce concentrations of organic contaminants, ammonia, and color in leachate. Pretreatment methods, anode materials, pH, current density, chloride concentration, and other additional electrolytes can considerably influence performance. Although high energy consumption and potential chlorinated organics formation may limit its application, electrochemical oxidation is a promising and powerful technology for treatment of landfill leachate.     

Longitudinal data analysis in support of functional stability concepts for leachate management at closed municipal landfills

Landfill functional stability provides a target that supports no environmental threat at the relevant point of exposure in the absence of active control systems. With respect to leachate management, this study investigates “gateway” indicators for functional stability in terms of the predictability of leachate characteristics, and thus potential threat to water quality posed by leachate emissions. Historical studies conducted on changes in municipal solid waste (MSW) leachate concentrations over time (longitudinal analysis) have concentrated on indicator compounds, primarily chemical oxygen demand (COD) and biochemical oxygen demand (BOD). However, validation of these studies using an expanded database and larger constituent sets has not been performed. This study evaluated leachate data using a mixed-effects regression model to determine the extent to which leachate constituent degradation can be predicted based on waste age or operational practices. The final dataset analyzed consisted of a total of 1402 samples from 101 MSW landfills. Results from the study indicated that all leachate constituents exhibit a decreasing trend with time in the post-closure period, with 16 of the 25 target analytes and aggregate classes exhibiting a statistically significant trend consistent with well-studied indicators such as BOD. Decreasing trends in BOD concentration after landfill closure can thus be considered representative of trends for many leachate constituents of concern.     

Consequences of raising the height of a landfill in a water-deficient climate

A large-scale field experiment has been carried out at the Coastal Park landfill which serves the City of Cape Town, South Africa. The landfill is unlined, and the City Council was under pressure from the central Government to cap and close the existing landfill and to establish an extension to the landfill with a lining to prevent the escape of leachate into the ground water. Measuring cells, installed to measure the rate of leachate flow from the landfill had shown that over a period of 9 years, from 1987 to 1995, leachate flow had averaged only 2% of rainfall. It therefore appeared possible, by increasing the moisture absorption capacity of the landfill, i.e., by increasing its height, to stop the leachate flow completely. If this could be achieved, there would be no need for a lining, and the raising would considerably extend the life of the landfill.The paper describes the experiment and its results, including the effects of the raising on leachate flow, settlement, leachate quality and the potential for polluting ground water, and the landfill’s water balance.     

Design considerations of constructed wetlands to reduce landfill leachate contamination in tropical regions

In tropical regions, landfill leachate contamination at municipal solid waste disposal sites is a critical issue because of the large volume of highly contaminated leachate formed during the rainy season. We evaluated the efficacy of constructed wetlands (CWs) with the ability to reduce the water volume and pollutant levels to reduce leachate contamination compared to the most commonly used treatment system, stabilization ponds, based on parameters obtained in a field experiment in Thailand. The simulation indicated that CWs had a higher potential to reduce the water volume than stabilization ponds over the course of a year. Scenario evaluations under varying initial water depths, system depths, and area sizes indicated that the CWs could reduce the treatment area to prevent overflow and leachate pollution. In addition, the CWs were estimated to reduce the leachate amount and pollution by 83–100% and 92–99%, respectively. When there is limited land available, deeper CWs can be used to sustainably prevent contamination from leachate overflow. Effectively designed CW systems may be valuable for both reducing the required area and the contamination; therefore, CWs are a promising option for sustainable landfill leachate treatment systems in developing tropical regions.     

Seasonal dynamics in leachate hydrochemistry and natural attenuation in surface run-off water from a tropical landfill

Open waste dump systems are still widely used in Indonesia. The Jatibarang landfill receives 650-700 tons of municipal waste per day from the city of Semarang, Central Java. Some of the leachate from the landfill flows via several natural and collection ponds to a nearby river. The objectives of the study were to identify seasonal landfill leachate characteristics in this surface water and to determine the occurrence of natural attenuation, in particular the potential for biodegradation, along the flow path. Monthly measurements of general landfill leachate parameters, organic matter-related factors and redox-related components revealed that leachate composition was influenced by seasonal precipitation. In the dry season, electrical conductivity and concentrations of BOD, COD, N-organic matter, ammonia, sulphate and calcium were significantly higher (1.1-2.3 fold) than during the wet season. Dilution was the major natural attenuation process acting on leachate. Heavy metals had the highest impact on river water quality. Between the landfill and the river, a fivefold dilution occurred during the dry season due to active springwater infiltration, while rainwater led to a twofold dilution in the wet season. Residence time of leachate in the surface leachate collection system was less than 70 days. Field measurements and laboratory experiments showed that during this period hardly any biodegradation of organic matter and ammonia occurred (less than 25%). However, the potential for biodegradation of organic matter and ammonia was clearly revealed during 700 days of incubation of leachate in the laboratory (over 65%). If the residence time of leachate discharge can be increased to allow for biodegradation processes and precipitation reactions, the polluting effects of leachate on the river can be diminished.     

Phytotoxicity of landfill leachate on willow – Salix amygdalina L.

Because of low investment and operational costs, interest is increasing in the use of willow plants in landfill leachate disposal. Toxic effects of leachate on the plants should be avoided in the initial period of growth and phytotoxicological testing may be helpful to select appropriate leachate dose rates. The aim of this study was to determine the phytotoxicity of landfill leachate on young willow (Salix amygdalina L.) cuttings, as a criterion for dose rate selection in the early phase of growth. Over a test period of 6 weeks plants were exposed to six concentrations of landfill leachate solutions (0%; 6.25%; 12.5%; 25%; 50% and 100%), under two different regimes. In regime A willow plants were cultivated in leachate solution from the beginning, whereas in regime B they were grown initially in clean water for 4 weeks, after which the water was exchanged for leachate solutions. The lowest effective concentration causing toxic effects (LOEC) was calculated (p < 0.05). In regime A LOEC was between 5.44% and 6.50% of leachate concentration, but slightly higher in regime B (5.32–6.59%). Willow plants were able to survive in landfill leachate solutions with electrical conductivity (EC) values up to 5.0 mS/cm in regime A, whereas in regime B plants were killed when EC exceeded 3.0 mS/cm. This indicates an ability of willow plants to tolerate higher strengths of landfill leachate if they are cultivated in such concentrations from the beginning.     

LCA and economic evaluation of landfill leachate and gas technologies

Landfills receiving a mix of waste, including organics, have developed dramatically over the last 3-4 decades; from open dumps to engineered facilities with extensive controls on leachate and gas. The conventional municipal landfill will in most climates produce a highly contaminated leachate and a significant amount of landfill gas. Leachate controls may include bottom liners and leachate collection systems as well as leachate treatment prior to discharge to surface water. Gas controls may include oxidizing top covers, gas collection systems with flares or gas utilization systems for production of electricity and heat.The importance of leachate and gas control measures in reducing the overall environmental impact from a conventional landfill was assessed by life-cycle-assessment (LCA). The direct cost for the measures were also estimated providing a basis for assessing which measures are the most cost-effective in reducing the impact from a conventional landfill. This was done by modeling landfills ranging from a simple open dump to highly engineered conventional landfills with energy recovery in form of heat or electricity. The modeling was done in the waste LCA model EASEWASTE. The results showed drastic improvements for most impact categories. Global warming went from an impact of 0.1 person equivalent (PE) for the dump to −0.05 PE for the best design. Similar improvements were found for photochemical ozone formation (0.02 PE to 0.002 PE) and stratospheric ozone formation (0.04 PE to 0.001 PE).For the toxic and spoiled groundwater impact categories the trend is not as clear. The reason for this was that the load to the environment shifted as more technologies were used. For the dump landfill the main impacts were impacts for spoiled groundwater due to lack of leachate collection, 2.3 PE down to 0.4 PE when leachate is collected. However, at the same time, leachate collection causes a slight increase in eco-toxicity and human toxicity via water (0.007E to 0.013PE and 0.002 to 0.003 PE respectively). The reason for this is that even if the leachate is treated, slight amounts of contaminants are released through emissions of treated wastewater to surface waters.The largest environmental improvement with regard to the direct cost of the landfill was the capping and leachate treatment system. The capping, though very cheap to establish, gave a huge benefit in lowered impacts, the leachate collection system though expensive gave large benefits as well. The other gas measures were found to give further improvements, for a minor increase in cost.     

Characterization and tropical seasonal variation of leachate: Results from landfill lysimeter studied

This study aims to characterize the leachate and to investigate the tropical climatic influence on leachate characteristics of lysimeter studies under different seasonal variations at KUET campus, Bangladesh. Three different situations of landfill were considered here as well as both the open dump lysimeter-A having a base liner and sanitary landfill lysimeter-B and C at two different types of cap liner were simulated. The leachate characteristics, leachate generation and climatic influence parameter had been continually monitored since June 2008 to May 2010, these periods cover both the dry and rainy season. The leachate generation had followed the rainfall pattern and the open dump lysimeter-A without top cover was recorded to have highest leachate generation. Moreover, the open dump lysimeter-A had lower total kjeldahl nitrogen (TKN), ammonia nitrogen (NH(4)-N) and TKN load, while both the COD concentration and load was higher compared with sanitary landfill lysimeter-B and C. In addition, sanitary landfill lysimeter-B, not only had lowest leachate generation, but also produces reasonable low COD concentration and load compared with open dump lysimeter-A. Result reveals that lysimeter operational mode had direct effect on leachate quality. Finally, it can be concluded that the knowledge of leachate quality will be useful in planning and providing remedial measures of proper liner system in sanitary landfill design and leachate treatment.