Abstract: Contents. Literature review. 2 Methodology.. 2 Applications, results and discussion.. 2 Conclusions 12. Introduction

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1 Abstract: Landfill is one of the primary methods for municipal solid waste disposal. In order to reduce the environmental damage and to protect the public health and welfare, choosing the site for landfill is of utmost importance. There are several primary factors such as soil characteristics, water bodies, land use and road network should be considered for choosing a site for landfill. The study was carried out for choosing a landfill site in Brazos County, Texas, USA. The possible potential sites for landfill can be determined with the help of GIS. The application of GIS in siting a landfill results in saving money and time. The data for each criterion was converted in to grid layers and was used to run the suitability analysis to determine the site for landfill. The buffer maps for each criterion was created based on the EPA regulations for landfill. The feature class was converted to raster data in order to do spatial analysis. The various grid layers are reclassified into new integer grids based on the potential factors. Finally, all the integer grids are combined and ranked together using raster calculator for selecting a potential landfill site. Contents Introduction 1 Literature review. 2 Methodology.. 2 Applications, results and discussion.. 2 Conclusions 12 Introduction The rise in urban population and industrialization resulted in stringent environmental regulations in order protect the environment and public welfare. The process of selecting a site for landfill is cumbersome and time consuming and needs to be dealt with large amount of spatial data. Moreover, while choosing a site it is very important to consider the state/federal laws concerning landfill, amount of waste generated and amount of waste to be land filled and the impacts of the landfill on the surroundings. The factors for choosing the landfill are considered on environment, engineering and social/cultural aspects [1]. Nowadays, GIS is widely used in land use suitability analysis since GIS can correlate and analyze the spatial relationship between several maps which are used for choosing the landfill site. The basic idea for selecting the site is that the prepared thematic maps are superimposed on one another and the most suitable site is decided based on the several factors we considered for choosing the site. Apart from saving time and cost, using GIS will also help us in monitoring the site with the developed digital data bank. The large amount of geographical data can be correlated easily with GIS and the results can be visualized through graphical representations.[2] In this project, the suitability analysis is carried out with raster data. 1

2 Literature Review Several studies were made in analyzing the suitability of a site selection. In most of the case the study was done using models like Index modeling, Multiple Criteria Decision Making, Weighted Linear combination and Boolean analysis. Usually, the decision maker sets weight for all the parameters which are considered before choosing a site for landfill. By using these models, we could be able to site an accurate location for landfill. The following literatures were reviewed for this study. Sumathi, V.R., Natesan, U., Sarkar, C., GIS Based Approach for Optimized Siting of Municipal Solid Waste Landfill. Waste Management 28, Gomes, E.G., Estellita Lins, M.P., Integrating Geographical Information Systems and Multi- Criteria Methods: A Case Study. Annals of Operations Research 116, Daneshvar, R., Fernandes, L., Customizing ArcMap Interface to Generate a User-friendly Landfill Site Selection GIS Tool. Environmental Informatics Archives, Volume 1, Mahini, S.A., Gholamalifard, M., Siting MSW Landfills with a Weighted Linear Combination methodology in a GIS Environment. Int. J. Environ. Sci. Tech., 3(4): A simple approach is done using ArcGIS in order to determine the suitable site for landfill in Brazos County, Texas. Without doing any modeling this study was carried out. This approach can give us the basic idea about the site and can be suitable only if the study area is small. This approach is used not only for landfill but also for siting a location for schools, construction of parks etc. Methodology The maps for all the site selection criteria for Brazos County, Texas was created using ArcGIS with the data obtained. The parameters considered for selecting the site were Proximity to Rivers Proximity to Lakes Distance from Roads Distance from Railroad Distance from Airport Distance from Residential Area Distance from Commercial Area Elevation For accurate results, we can further add more parameters like Air Quality Index, Ground water table data, geology, flood data, wetlands etc. The basic approach is that to build a suitability model through which we can able to determine a suitable location for Landfill. The above said input datasets are scaled to 1 to 5 by reclassifying. Then appropriate weights are given using weighted overlay analysis to get the final output by setting the percentage of influence of each datasets. [3] Application, Results and Discussion The suitable site for landfill in Brazos County, Texas was studied using Spatial Analysis tool in ArcGIS. In the map created using the data collected, buffers are created using Multiple Ring Buffer function for different distances. The buffer shape file was then converted into raster data using Feature to Raster function. The values 2

3 of the input raster data can be modified and prioritized using the function Reclassify. The same procedure is followed for all the shapefiles created using the data obtained. The data was collected from ESRI, TIGER, Geocommunity, Google Earth(Airport), TAMU-Library. The GIS files for Rivers, County Boundary from city of College Station website [4]. Brazos County was downloaded from Centre for Geospatial Technology, Texas Tech University. The Elevation data was obtained from Texas Natural Resources Information System. The Landuse data was obtained from Evan Library, Texas A&M University, Texas. The GIS file for Rail road was downloaded from ESRI. Road & Rail Network Map Using the data obtained, the road map ( Fig.1) was created in ArcGIS. For finding the suitable location, first buffers were created around the roads. Using the function Multiple Ring Buffer option, buffers were created for 15m, 150m, 250m, 350m and 500m. The buffer shape file was then converted to raster file using the function Feature to Raster. The grid cell values are prioritized such that the longer distance was rated one and so on. The final map is shown in Fig.1 and Fig 2. Fig 1. Road Map Brazos County Fig.2. Road Network - Reclassify 3

4 Rivers & Lakes Map The river map was created and using the function Multiple Ring Buffer, buffers are created for distance of 30m, 100m, 200m, 300m, and 500m. The buffer shape was converted in to raster data and reclassification was done. The final maps for rivers are shown in Fig.3 & Fig.4 and for lakes are shown in Fig.5 & Fig.6 Fig.3. River Maps Brazos County Fig.4. Rivers Map - Reclassified 4

5 Fig.5. Lakes Map Brazos County Fig.6. Lakes Map - Reclassified Residential & Commercial Area Map The Landuse map was created using ArcGIS. The residential areas were selected using the function Selection by Attributes and a separate layer was created for this selection. Buffer for the selection layer was created using Multiple Ring Buffer for 15m, 150m, 250m, 350m and 500m. The new buffer layer was converted in to a new raster data and reclassification was done. Similarly commercial area map was created. The maps residential are shown in Fig.7 & Fig.8 and similarly the maps for commercial area are shown in Fig.9 and Fig.10. Airports Map The Airports map for Brazos County was created using Google Earth. The Geographic Coordinates for all the airports in Brazos County was taken from Google earth. A new dbase table was created in the Arc Catalog. The co-ordinates are added in the attribute table using the function Edit. The table data was exported in order to create a new shape file giving the corresponding coordinate system. The buffer distance in the new shape file was created for each point using the function Multiple Ring Buffer for 100m, 200m, 300m, 400m and 600m. The buffered shape file is then converted into raster data and reclassification was done. The Maps are shown in the Fig.11 and Fig.12. 5

6 Airport Name Longitude Latitude Coulter Field Easterwood field st.joseph Heliport TAMU Flight station Tom j Moore Airport Varisco Airport Fig.7. Land Use Map Brazos County Fig.8. Residential Map - Reclassified 6

7 Fig.9. Land Use Map Brazos County Fig.10. Commercial Map Reclassified Municipal Solid Waste disposal sites Map The municipal solid waste disposal site for the state Texas was obtained from TCEQ. In the attribute table, the sites for Brazos County were selected using the function Selection from Attributes. It s a point shape file and buffer distances were created for 30m, 150m, 250m, 350m and 500m. The buffered shape file was then converted into raster data using function Feature to Raster. Similarly the grid values are prioritized using the function Reclassify. The maps are shown in the Fig.13 and Fig.14. Elevation The Elevation map for the state Texas was obtained. The Brazos County was selected from the shape file. A separate shape file for Brazos County was created using the function Clip. The same is converted in to raster data using the function Feature to Raster. Using the function Slope, the slope for the raster data was determined. The maps are shown in the Fig.15, Fig.16 and Fig.17 7

8 Fig.11. Airports Map Brazos County Fig.12. Airport Map Reclassified 8

9 Fig.13. MSW sites Map Brazos County Fig.14. MSW sites Map Reclassified 9

10 Fig.15. Elevation Map Texas Fig.16. Elevation Map- Brazos County 10

11 Suitability Analysis Fig.17. Slope Map Brazos County The raster maps created for all the parameters are over laid to each other in order do the suitability analysis. Using the Weighted Overlay Analysis, the values of all the datasets can be evaluated and ranked. The default scale evaluation of 1 to 9 by 1 was used for the analysis. All the raster data was added to the weighted tool. The reclassified values are shown in the field values. The percentage of influence of all the data sets can be specified. In this study, the percentage of influence was set equal for all the datasets. The final map is shown in the Fig

12 Fig.18. Overlay Analysis Map Brazos County Conclusion This is a simple approach for selecting a site for Landfill. Several models like Multi Criterion Decision Making, Index Modeling and IDW have been made in order to find the accurate location for landfill. This study can be further made accurate by choosing more parameters like Air quality Index, flood plain data, wetlands, parks etc. 12

13 References: [1] Daneshvar, R., Fernandes, L., Customizing ArcMap Interface to Generate a User-friendly Landfill Site Selection GIS Tool. Environmental Informatics Archives, Volume 1, [2] Sumathi, V.R., Natesan, U., Sarkar, C., GIS Based Approach for Optimized Siting of Municipal Solid Waste Landfill. Waste Management 28, [3] [4] 13