identification and assessment of potential environmental impact of cesspits on selected groundwater...
TRANSCRIPT
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Identification and assessment of Potential Environmental Impact of Cesspits on Selected Groundwater Wells and
Springs in the West Bank using Modeling
Supervisor: Dr. Mohammad N. Almasri
By: Lina Mahmmoud Hamarshi
Proposal Presentation
February 14, 2011
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General background
In many rural Palestinian areas, wastewater is not collected via a sewerage network but rather it is being disposed of through cesspits.
The majority of cesspits that are in use in the West Bank are not coated or lined and thus wastewater will leach down and percolate and may affect the quality of groundwater.
Groundwater is considered the main fresh water resource in the West Bank and definitely the only reliable source for water supply for Palestinians.
Because of that, protecting groundwater from pollution is a priority. To protect groundwater from pollution, investigating and targeting the potential sources of pollution is vital. One of these sources is cesspits that are considered as concentrated point sources of pollution.
Most wells and springs in the West Bank have shown high concentrations of nitrate and organic pollutants in areas with cesspits.
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There are many of the communities in the West Bank lies on the outcropping areas.
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Research Hypothesis
The cesspits are the main source of pollution for many groundwater wells and springs in the West Bank.
Effect of contaminates originating from cesspits on
nearly well
Transport of nitrate from cesspits to groundwater well
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ObjectivesThe following are the key objectives:
Identification of the wells and springs in the West Bank that encounter heavy contamination especially from cesspits.
To develop a simple yet realistic methodology that can be utilized to assess the potential contamination of groundwater wells and springs due to cesspits.
To implement this methodology by developing a particle- track model using MODFLOW and MODPATH for a specific case study in the West Bank.
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Expected Output A map that highlights the locations of the wells and springs of high contamination.
A map that depicts the locations of the wells and springs that are polluted from cesspits.
A modeling framework that can be used for better assessing the potential of the wells and springs contamination from cesspits.
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Methodology
Problem Description
Selection of contaminated springs and wells
Development of a groundwater particle tracking model
Conclusions and Recommendations
Output Analysis
Data collectionInterviewsfield visit
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Contributing area of the well
Particles from cesspits intersects with catchment
area of the well
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MODPATH
MODPATH is groundwater particle-tracking program, and is a post-processing program for MODFLOW to simulate the movement of contamination from point source of
pollution to the groundwater resource .
Particles can be tracked either forward or backward in time .
http://www.aquaveo.com/modpath
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Literature review
The percentage of household that used cesspits in the West Bank by type of locality and region is 59.7% in urban area, 93.4% in rural area, and 29.1% in camps.
Cesspits are considered as point sources of pollution that are widespread in the West Bank.
In high density residential areas with no sewer systems, cesspits produce significant amounts of contamination such as nitrates, bacteria, and organic matter. This form of pollution is a concern to rural homeowners who use groundwater wells for domestic use.
Elevated concentrations of contaminants in drinking water can cause serious diseases.
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There are many associated problems that transpire from such a practice which is in fact very common and these problems can be summarized as follows:
1. Loss of wastewater that can be collected, treated, and later reused.
2. Since the most of cesspits are not coated or lined, then wastewater will leach down and percolate and may affect the quality of ground water.
The uncontrolled flow of sewage causes many environmental problems and health hazards, these problems can be summarized as follows:3. Destruction of Agricultural land and crops.4. Bad odors and spread of mosquito which affecting
negatively into healthy.
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The recommended solutions that reduce the effect of cesspits in groundwater resources can be summarized as follows:
1. Link all the communities in the West Bank with the public sewage network if it may possible.
2. Replace all cesspits that used in the communities of the West Bank to septic tank.
3. Develop the wastewater services in the West Bank.
4. Develop the planning and management of groundwater resources in the West Bank under the current and future challenges.
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Time schedule
J F M A M J J A S O N D
Data collection
Literature review
Selection of contaminant wells and springs
Identify the need and required tools to be mastered
Develop a model
Analysis of the results
Recommendations and conclusions
Thesis write-up
Defense
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References
Almasri, Mohammad N., 2007, Nitrate contamination of groundwater: A conceptual management framework. Environmental Impact Assessment Review, 27: 220–242.
Anayah, Fathi and Mohammad N. Almasri, 2009. Trends and occurrences of nitrate in the groundwater of the West Bank, Palestine. Applied Geography, 29(4): 588–601.
Bilgehan Nas, Ali Berktay, 2006, Groundwater contamination by nitrates in the city of Konya, (Turkey): A GIS perspective. Journal of Environmental Management, 79: 30–37.
K. E. Murray, D. R. Straud, and W. W. Hammond, 2007. Characterizing groundwater flow in a faulted karst system using optical brighteners from septic systems as tracers. Environmental Geology 53:769–776.
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References
Luay J. Froukh, 2002: Groundwater Modeling in Aquifers with highly Karstic and Heterogeneous Characteristics (KHC) in Palestine. Water Resources Management. pp. 369-379.
MacQuarrie, K. T. B., E. Sudicky, and W. D. Robertson. 2001. Numerical simulation of a fine-grained denitrification layer for removing septic system nitrate from shallow groundwater. Journal of Hydrology 52: 29-55.
Monther Hind, 2004, Investigation on Groundwater Pollution: Field investigation in special locations in North and West of the West Bank, Palestinian Wastewater Engineers Group (PWEG).
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References
PCBS. (2008). (Palestinian Central Bureau of Statistics). Available from: http://www.pcbs.gov.ps/Portals/_pcbs/populati/demd3.aspx.
PWA. (2003). (Palestinian Water Authority). Water resources in the West Bank and Gaza strip.
PWA. (2007). (Palestinian Water Authority). Domestic quality for wells and springs.
Yintao Lu, Changyuan Tang, Jianyao Chen and Yasuo Sakura, 2008. Impact of septic tank systems on local groundwater quality and water supply in the Pearl River Delta, China: case study. Hydrological Processes 22, 443–450.
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Thank
You