GROUNDWATER CONTAMINATION ASSESSMENT IN THE VICINITY OF ABQAIQ LANDFILL, EASTERN SAUDI ARABIA-GIS APPROACH

Transcription

1 GROUNDWATER CONTAMINATION ASSESSMENT IN THE VICINITY OF ABQAIQ LANDFILL, EASTERN SAUDI ARABIA-GIS APPROACH By Salman F. Al-Khaldi Environmental Sciences

2 Introduction Outline Landfill Classes and Methods Landfill Problems Landfill Leachate Groundwater contamination by leachate Problem Statement Objectives Description of the Study area Methods Limitations Discussion and Analysis Conclusion Recommendation

3 Introduction Water Supply vs Demand in SA Water Supply Water Demand Quantity MCM Year Scarcity of water resources in Saudi Arabia Quantity and quality of groundwater must be protected and efficiently managed. Prevention is better than Cure.

4 Introduction Sources of groundwater contamination are extensive. Landfills are considered one of the major sources of contamination to groundwater. What is Landfilling? Landfills have became critical to most waste management strategies. Simple, Cheap, and Most cost effective method of waste disposal, Despite their sophisticated engineered design, eventually will fail and leak leachate into groundwater.

5 Landfill Classes and Methods Landfills are classified based on wastes disposed into: Class I-Hazardous Waste Class II- Non-hazardous Class III-Non water-soluble Based on method of Landfilling are classified into: Area Progressive Trench Depression

6 Landfill Problems Landfills can present problems with respect to: Aesthetic Spread of disease Odors Fires Contamination of groundwater Gas emissions

7 Landfill Leachate All Landfills generate leachate. Factors affecting the composition of landfill leachate include: Landfill material Landfill conditions Characteristics of entering water Soil characteristics under the landfill

8 Groundwater contamination by leachate Factors governing the degree of groundwater contamination by landfill leachate: Depth of the water table Concentration of contaminants Permeability of the geologic strata Type of geologic strata The toxicity of the contaminants The direction of groundwater flow

9 Problem Statement Landfill leachate contamination to groundwater resources. In an attempt to protect valuable groundwater resources from leachate contamination generated by landfills, an assessment of the groundwater contamination in the vicinity of Abqaiq landfill in eastern province in Saudi Arabia is to be conducted.

10 Study Objectives Description of the site geology and hydrogeology Collection and analysis of groundwater samples for contaminants presence. Applying GIS to evaluating the contaminants extent Applying GIS to Create contaminant transport model of the study area. Suggesting cost-effective remedial approaches available.

11 Methods Field work Identify The disposed wastes Identify the Landfills design Identify the site characters Lab methods Geochemical analysis Heavy metals Hydrocarbon contaminants Modeling and Contouring GIS Best remedial methods

12 STUDY LIMITATIONS Finding and accessing suitable data Lack of training on GIS to exploit it s potentials to it s full

13 Description of the Study area Abqaiq city is located 75 KM south of Dammam city (25.56 N E) Low TDS shallow groundwater (2,500-6,000 mg/l)

14 Geology of the study area There are four principle aquifers beneath Abqaiq Area: 1. The Neogene Formation and the Alat Member of the Dammam Formation (Alat). 2. The Khobar aquifer a member of the Dammam Formation. 3. The confined Umm Er Radhuma (UER) Formation 4. The confined Wasia Formation The rocks consist of marly sandstone, sandy marl, sand, clay and sandy limestone

15 Abqaiq Landfill Located 5 KM south of Abqaiq city. Constructed in 1994 with three monitoring wells installed.

16 0 Scale 1000m APWT-12 APWT-13 DISCUSSION AND ANALYSIS APWT-30 Southwest Basin APWT-32 APWT-11 Increased levels of Total Dissolved Solids (TDS) Increased levels of Total Organic Carbon (TOC) Lake Abqaiq Former RDDS Site tds04_interp APWT-1 GOSP Abqaiq LF LEGEND: APWT-22 GCMP Monitoring Well ABLF-2 Scale m Water Level Contour Abqaiq LF: TDS and Flow Contours

17 RECOMMENDATIONS More collaboration from different organizations Covering a wider area to include other landfills in Saudi Arabia.

18 Conclusion High water demands and resource scarcity deem efficient and effective resource management. Protecting our water resources is of a paramount importance. Landfill generated leachate is one of the potential contaminants to shallow groundwater. Different strategies can be employed to define, measure, and remediate contaminants.

19 THANK YOU

20 Mass Transport Model