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Environmental risk assessment is one of the key tools in environmental engineering. This risk assessment can be qualitative or quantitative and it is based on preliminary studies i.e., baseline study for waste disposal sites. Even though the literature exists on baseline study in general, still there is a lack of guidance regarding development of a site-specific baseline study model for a waste disposal site. This study has two-fold aim, firstly, how to develop site-specific baseline study model for a selected dumping site, and secondly, how this site-specific baseline study can support the environmental engineering via mathematical risk estimation. Mahmood Booti Open Dumping Site (MBODS) is selected to demonstrate the development and application of site-specific baseline study model. This is followed by building a framework that shows how the output of the baseline study can lead to environmental engineering via mathematical risk estimation. The paper provides a mechanism of how to construct a bespoke baseline-study model that is readily useable, avoiding procurement of expensive computer software and yet smoothly connecting with the follow-on stages of the risk assessment. The work presented in this paper can be reproduced repeatedly to create site-specific baseline study models for risk assessment of other waste disposal sites in a cost-effective, consistent and cohesive manner. [ABSTRACT FROM AUTHOR]

This study investigated the seasonal and temporal variations in the extent and source of physiochemical and toxic trace elements in the Lakhodair landfill site of Lahore, Pakistan. For this purpose, systematic composite samples were collected every month, consecutively for 1 year, and analyzed for different physiochemical parameters and trace elements. The results of TDS, TSS, COD, NH3-N, BOD5, sulfate, sulfides, phenolic compounds, and oil and grease were higher than the national environmental quality standard (NEQs). The concentrations of trace elements, especially Mn (1.7 mg/L) and Cd (0.05 mg/L), were above the MPL, while Fe (14 mg/L), Ni (1.6 mg/L), and Zn (6.7 mg/L) were also found higher than the NEQs in some samples. In Lakhodair leachates, the TDS, COD, NH3-N, BOD5, sulfides, and Cl− have high concentration coefficient (i.e., CC 3 to > 6), which falls in the category of considerable to high contamination and risk level, while the remaining parameters were in the category of low to moderate contamination (CC 1 to ≤ 3) and moderate risk. The lower BOD5/COD ratio (< 0.1) in spring and autumn seasons represents the active methanogenesis and anaerobic activities in the Lakhodair landfill site. The anaerobic and methanogenesis activities enhance the redox reaction as a result of CO2 emission, which increases the pH, TDS, COD, Cl−, BOD5, NH3-N, sulfides, and phenolic compounds in the leachate site. However, the lower concentrations of some trace elements in leachate may be because of an anaerobic process that may immobilize the trace elements. It is presumed that the trace elements in the Lakhodair landfill may be in a metastable state, which is difficult to leach out. It is hereby recommended that leachate produced in the Lakhodair landfill site should be handled carefully to limit the environmental and health implications. [ABSTRACT FROM AUTHOR]

Shortage of land for waste disposal and inappropriate landfill site is one of the biggest problems in urban areas. This problem could be solved by applying new technologies like Geographic Information Systems. Most of the landfill sites in Pakistan are selected randomly, and waste is burned in air which has impacts on nature and human lives. The main aim of this research is to determine a suitable landfill site with less impact on environment. In this research, a potential site for an appropriate landfill area for Faisalabad city was determined by using Geographic Information System (GIS) as a tool to aid the decision making process. To achieve this purpose, thematic layers, and different tabular data such as topography, land use, roads network, ground, and surface water, infrastructure, and urban areas were collected. Thematic maps were used to create the vulnerability map for the area and the results were compiled to the buffer zones around sensitive areas. Multi-criteria analysis (MDA) was used to measure the relative importance weighting for each criterion. Each map layers were formed with the aid of GIS and final suitability map was created by overlay analyses of each criterion map. According to obtained results, high and low suitable areas were determined in the study area. [ABSTRACT FROM AUTHOR]