The first step: screening potential areas by using modified criteria from the PCD
in order to achieve suitable criteria used in this study. Due to each of areas in Thailand have
different environmental characteristics in topography, hydrology, geology, and etc., therefore,
siting criteria should be used flexibly to help make better decisions for siting analysis. The criteria
were selected by taking into account environmental characteristic of the area. The criteria
considered several factors were shown as follow:
Watershed class: landfill should not be located within watershed areas class 1
and class 2.
Flood risk: landfill should not be located in flood risk area.
Stream and lake: landfill should be located more than 300 meters.
Groundwater table: landfill should not be located within areas where the
groundwater table less than 1.5 meters below the base of the landfill.
Recharge area: landfill should not be located within recharge area.
Well and wastewater treatment plant: landfill should be located more than 700
meters of any water supply well and wastewater treatment plant.
Soil: landfill should have natural clay liner or clay available for liner, and final
cover material available. Avoid sites with highly permeable soil. (Suggested site
hydraulic conductivity of not over 3×10-5
)
National park and forest zone: landfill should not be located in this area.
Major road: landfill should be located more than 100 meters but less than 10,000
meters.
Airport: landfill should be located more than 5,000 meters around airports as
notified by the regulatory authority or the aviation authority.
Community area: landfill should be located more than 3,000 meters.