Quantification of leachate discharged to groundwater using the water balance method and the Hydrologic Evaluation of Landfill Performance (HELP) model

Landfills are a source of groundwater pollution in Gaza Strip. This study focused on Deir Al Balah landfill, which is a unique sanitary landfill site in Gaza Strip (i.e. it has a lining system and a leachate recirculation system). The objective of this article is to assess the generated leachate quantity and percolation to the groundwater aquifer at a specific site, using the approaches of (i) the Hydrologic Evaluation of Landfill Performance model (HELP) and (ii) the water balance method (WBM). The results show that when using the HELP model, the average volume of leachate discharged from Deir Al Balah landfill during the period 1997 to 2007 was around, 6800 m3/year. Meanwhile, the average volume of leachate percolated through the clay layer was 550 m3/year, which represents around 8% of the generated leachate. Meanwhile, the WBM indicated that the average volume of leachate discharged from Deir Al Balah

Comparison and Optimization of ozone – Based Advanced Oxidation Processes in The Treatment of Stabilized Landfill Leachate

-Leachate pollution is one of the main problems in landfilling. Among the most problematic parameters in stabilized leachate are COD, ammonia, and color. The treatment technology that can be used may differ based on the type of leachate produced. Even after treatment, the effluent characteristics are always hard to comply with the discharge standard. Ozonation is one of the chemical processes that can be used in the treatment of landfill leachate. However, its performance when use alone is low; its effectiveness can be improved using advanced oxidants. To date, application of Fenton and persulfate reagents separately to improve ozonation process in one ozone reactor was not well established. The study aimed to evaluate and compare the performance of the three treatment processes, namely ozone, ozone/Fenton and ozone/persulfate in treating stabilized leachate separately at different experimental conditions. The performance of the three methods in the treating stabilized leachate was compared. According to the results, the performance of ozone alone was poor, and utilizing new advanced oxidation material during ozonation of such leachate was required to improve leachate treatability. Ozone/Fenton process is a viable choice for degrading and decolourizing stabilized leachate. Furthermore, ozone/persulfate process has higher performance in ammonia removal as well as it has good removal efficiency of COD and color from stabilized leachate. Suitable data for establishing fully stabilized leachate treatment plant using ozone/Fenton and ozone/persulfate was suggested. The final effluent of ozone/Fenton process complied with the discharge standard for COD and colour

Evaluating impacts of recharging partially treated wastewater on groundwater aquifer in semi-arid region by integration of monitoring program and GIS technique

Abunada, Z ORCiD: 0000-0002-4143-1603The current study investigates the impact of recharging of partially treated wastewater through an infiltration basin on the groundwater aquifer quality parameters. A monitoring program supported by a geographic information analysis (GIS) tool was used to conduct this study. Groundwater samples from the entire surrounding boreholes located downstream the infiltration basin, in addition to samples from the recharged wastewater coming from the Beit Lahia wastewater treatment (BLWWTP), were monitored and analysed between 2011 and 2014. The analysis was then compared with the available historical data since 2008. Results revealed a groundwater replenishment with the groundwater level increased by 1.0–2.0 m during the study period. It also showed a slight improvement in the groundwater quality parameters, mainly a decrease in TDS, Cl⁻ and NO3⁻ levels by 5.5, 17.1 and 20%, respectively, resulting from the relatively better quality of the recharged wastewater. Nevertheless, the level of boron and ammonium in the groundwater wells showed a significant increase over time by 96 and 100%, respectively. Moreover, the infiltration rate was slowed down in time due to the relatively high level of total suspended solid (TSS) in the infiltrated wastewater

Analysis of landfill components in estimating the percolated leachate to groundwater using the HELP model

Landfills are one of the groundwater pollution sources in Gaza Strip. This study focuses on two landfills operating in Gaza Strip; the first is Dear Al Balah landfill which has a lining system and the second landfill is Gaza landfill which does not have a lining system. The main objective of the present study is to assess the effect of landfill components on percolated leachate to groundwater aquifer using the Hydrologic Evaluation of Landfill Performance (HELP) model. A comprehensive analysis of landfill components affecting the generated leachate was conducted. The results showed that the landfill components were ordered in priority according to their effects on percolated leachate through clay layer as follows: (1) existing of lining system enhances the percolation reduction up to 87%, (2) 30% reduction of rainfall level enhances the percolation reduction up to 50%, (3) 50% reduction of existing landfill area enhances

Assessment of groundwater quality due to municipal solid waste landfills leachate

Landfills are one of the groundwater pollution sources in Gaza Strip. This study focuses on two landfills operating in Gaza Strip; the first is Dear Al Balah landfill which has a lining system and the second Gaza landfill which does not have lining system. The objective of this study was assessment degree of groundwater pollution around the two landfills due to percolated leachate from the two landfills. Groundwater samples from 18 water wells located downstream of landfills in addition to two leachate samples were collected during dry season in November 2008 to study possible impact of leachate percolation into groundwater. Several physical and chemical parameters were tested in groundwater and leachate samples, these include temperature, pH and EC, NO 3, NH 4, Cl, SO 4, BOD, COD, TOC, Pb, Fe, Cu, Cd, Zn. The Geographic Information System (GIS) was used as a tool to illustrate spatial distribution of the pollutant indicators around both landfills in the periods 1995, 1999, 2001 and 2008, respectively. The results showed that most of wells were contaminated, where concentration of most physical and chemical parameters were above acceptable standard levels for potable or irrigation water. It is quite evident that landfills present potential threats to the surrounding environment

Risk assessment of nitrate transport through subsurface layers and groundwater using experimental and modeling approach

Landfills are one of the main point sources of groundwater pollution. This research mainly aims to assess the risk of nitrate (NO-3) transport from the unlined landfill to subsurface layers and groundwater using experimental results and the SESOIL model. Samples from 12 groundwater wells downstream of the landfill were collected and analyzed in 2008, 21 years after the landfill construction. The average NO-3 concentration in the wells was 54 mg/L, slightly higher than the World Health Organization (NO-350 mg/L) standards. SESOIL model was used to predict the NO-3 concentration at the bottom of the unsaturated zone. Results indicated that the current mean NO-3 concentration at the bottom of the unsaturated zone is 75 mg/L. the model predicted that the level of NO3 will increased up to 325 mg/L within 30 years. Accordingly, the NO-3 concentration in groundwater wells near the landfill area is expected to gradually increase with time. Although the current risk associated with the NO-3 level might not be harm to adults, however, it might pose severe risks to both adults and infants in the near future due to NO-3 leaching. Urgent mitigation measures such as final cell cover (cap), lining system and vertical expansion should be considered at the landfill to protect the public health in the area. © 2017, © 2017 Informa UK Limited, trading as Taylor & Francis Group

The application of SWAT-GIS tool to improve the recharge factor in the DRASTIC framework: Case study

The robustness of groundwater vulnerability assessment using the conventional DRASTIC framework is highly dependent on the quality of the input data. The current study investigates the vulnerability of the western part of the coastal aquifer of the Gaza Strip, part of the Palestinian southern-western coastal aquifer. The study intends to re-introduce the recharge factor (R) in DRASTIC framework through the application of SWAT model and investigates its impact on the quality of vulnerability assessment compared with the conventional DRASTIC framework (No SWAT). Not only a higher recharge resolution map was generated when applying the SWAT model, but also an improved vulnerability index by 52% due to the incorporation of the local zonal-operation vulnerability concept was achieved. While the conventional DRASTIC framework (No SWAT) resulted in 74% of the study area has either extreme high or extreme low vulnerability classes, SWAT model was able to smoothen the vulnerability identification by capturing the slight gradual vulnerability variation over the study area with more precise vulnerability assessment. The resulted vulnerability assessment was validated using real field nitratedata(NO3-) of water samples collected from the entire study area. The vulnerability assessment using the SWAT model was in good agreement with the nitrate levels in the area compared with the conventional DRASTIC where the residual error encountered in the case of SWAT application (20%) was less than in the conventional DRASTIC;(77%). The results were also validated using receiver operator classification (ROC) and the area under curve (AUC) confirming the improved assessment due to SWAT model application. The current new approach is sought to support the decision-making process and water managers to better manage the proposed aquifer recharge scheme in the study area as well as to better manage the limited water resources

Risk assessment of nitrate transport through subsurface layers and groundwater using experimental and modeling approach

Landfills are one of the main point sources of groundwater pollution. This research mainly aims to assess the risk of nitrate (NO-3) transport from the unlined landfill to subsurface layers and groundwater using experimental results and the SESOIL model. Samples from 12 groundwater wells downstream of the landfill were collected and analyzed in 2008, 21 years after the landfill construction. The average NO-3 concentration in the wells was 54 mg/L, slightly higher than the World Health Organization (NO-350 mg/L) standards. SESOIL model was used to predict the NO-3 concentration at the bottom of the unsaturated zone. Results indicated that the current mean NO-3 concentration at the bottom of the unsaturated zone is 75 mg/L. the model predicted that the level of NO3 will increased up to 325 mg/L within 30 years. Accordingly, the NO-3 concentration in groundwater wells near the landfill area is expected to gradually increase with time. Although the current risk associated with the NO-3 level might not be harm to adults, however, it might pose severe risks to both adults and infants in the near future due to NO-3 leaching. Urgent mitigation measures such as final cell cover (cap), lining system and vertical expansion should be considered at the landfill to protect the public health in the area. © 2017, © 2017 Informa UK Limited, trading as Taylor & Francis Group