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GIS 301 - Skyline College - Forsberg

Assignment 3:
Finding a suitable site for a landfill

Scenario:

You have been asked to decide which is the most suitable site for a proposed landfill to be located in northern San Mateo county.  In this assignment you will manually use the GIS methods of overlay and buffering to collect a variety of data from several maps of the area. After reviewing the data, you must pinpoint what you consider the most suitable place for a new landfill.in northern San Mateo county. You should be prepared to present and defend your decision to the rest of the class.


Analysis of Maps

Each group will get a clear plastic map of the area which is the same size as the maps to be analyzed. Lay the plastic map over the maps of data and block out areas inappropriate for a landfill with the pens provided.

Buffering
A landfill must be located at least a half mile away from airports and one quarter mile away from earthquake fault-lines. You will need to find these features and draw a buffer around them to create a polygon blocking out places  where the landfill cannot be placed. The landfill should also be located at a high enough altitude to prevent flooding caused by sea-level rise. You must draw a buffer to exclude areas along the coast less than 5 feet above sea level.

Overlay
A landfill must be located on land with soil rich in clay content. You will need to block out those areas that do not have clay-type soils. A landfill must be located away from homes and businesses. Block out residential, commercial, and other areas of landuse that are incompatible with a landfill. The landfill should also be located in a geologically stable area. Block out areas with a moderate or high susceptibility to fail in a major earthquake, and areas with more than a 6% probability of debris-flow occurence during a major winter storm.

Final Analysis
Once you have completed buffering and overlay procedures, you will find that those places that were not blocked out are possible sites for the landfill. Using what you know of the area, choose what you consider to be the best site for the landfill. Be ready to present your decision to the rest of the class, and prepare to defend your decision.

Summary:

Landuse map: Block out residential, commercial, and other areas of landuse that are incompatible with a landfill. Block out anything within a half mile of an airport.

Debris-flow probability map: Block out areas with more than a 6% probability of debris-flow occurence.

Slope stability during earthquakes map: Block out anything within a quarter mile of an earthquake faultline, and areas with a moderate or high susceptibility to fail in a major earthquake.

Soils map: Block out areas that do not have clay-type soils.

Topographic map: Block out areas along the coast less than 5 feet above sea level.


Based on a scenario layed out in Getting to Know ArcView GIS 1997 ESRI & GeoInformation Intl. pp.3.16 - 3.17