الفهرس 
Problem statementOnly 14 pages are availabe for public view
 |  | from | 193 |  |  |
| | | from | 193 | | |
Abstract
Municipal solid waste (MSW) is considered to be one of the biggest
challenges facing most of the developing countries including Egypt.
Notwithstanding the fact that there are various methods used in the disposal of MSW, landfilling remains an attractive disposal method after applying proper upstream feasible management interventions. The landfill is an engineering structure constructed to contain waste, and prevent contaminants generated from waste reactions from polluting the surrounding environment such as leachate. In developing countries, landfills (and what originally developed as dump areas) usually become unsuccessful after a while in operation for many reasons including receiving medical, and hazardous waste which contains dangerous substances unsuitable for landfilling, and besides, uncontrolled leachate collection that may cause percolation of leachate into the soil, and groundwater (GW).
When MSW is placed in the landfill, MSW becomes subjected to GW underflow and rainfalls. This liquid contained in the waste becomes leachate during waste decomposition and percolation through the landfill body. Improperly designed or operated landfills have some impacts on the environment. These impacts are represented in gases and leachates which
may migrate from the landfill if not controlled. These impacts result in
spontaneous fires, explosions, vegetation damage, unpleasant odors, settlements, soil, and groundwater pollution. In developing countries, landfills usually become unsuccessful after a while in operation for many reasons including receiving medical, and
hazardous waste which contains a dangerous substance, and an
uncontrolled leachate collection system which may cause the percolation
of leachate into the soil, and groundwater (GW). The primary objective of this study is to investigate the effect of acute contamination of groundwater quality by chloride, and other parameters as an indicator to assess such impact and identify its possible causes where one potential cause could be related to liner deterioration over time, and
improper landfilling techniques. Chloride is usually considered as a tracer for GW contamination by leachate and is used to assess the effect of
landfills on GW.
The case study of this research is El-Sadat landfill which is the final
disposal site for Gharbia governorate dedicated for them by Menofia governorate in 2001 for being the nearest desert area available close to
Gharbia governorate. El-Sadat landfill was established in 2007. El-Sadat
landfill has an approximate area of 80 feddans (336,000 m2). Out of the 12
cells of the landfill, seven cells were closed, one cell is in operation, and
four cells (considered for future extension) are not yet constructed. Each
cell volume is 375,000 m3
, where the daily amount of waste transferred to the landfill varies from 1000:1500 m3.
A set of groundwater sampling was chosen and fixed to monitor groundwater quality over several years where two locations downstream, and one location upstream of the landfill were selected.
The analyzed samples indicated that the concentration of chloride in groundwater downstream El-Sadat landfill is almost double the concentration of chloride in the upstream samples.
A software package was also used in this study to simulate a numerical model for the effect of liner deterioration over time, and contaminant migration on groundwater underneath the sanitary landfill site. This numerical model considered 3 different cases of GW flow direction according to the common GW flow direction in the area.
The numerical model cases were found very close to the GW samples analyzed (especially case 2) that also match the GW local flow direction obtained. Through chemical analysis made, Cl concentrations were found in soil
samples collected during boreholes implementation in the site. These
concentrations were found higher in value in samples close to the ground
surface than deep samples which assure that this Cl contamination source
is leachate and migrates through the soil to GW. This study recommends a remedial measure for the landfill to extract the leachate from the bottom of the cells (as the leachate collection system has been broken for many years, and cannot be fixed) to reduce the
migration of the contaminants by drilling wells in the lowest points in each cell to pump out the accumulated leachate to reduce the head of the
mounds. The extraction wells shall be equipped with a leachate submersible pump that should be connected to the evaporation ponds.
Applying the 3-R techniques (reduce, reuse, and recycle) in Egypt and
especially in the Gharbia governorate shall affect positively the waste
quantity and quality reaching El-Sadat landfill which will, in turn, affect
the quality and quantity of leachate generated.