Selection of optimal aggregation function for the revised leachate pollution index (r-LPI)

Area of Science:

• Environmental Science
• Water Quality Assessment
• Waste Management

Background:

• Landfill leachate poses significant pollution risks.
• Quantifying leachate pollution potential is crucial for environmental protection.
• Existing methods may lack comprehensive assessment capabilities.

Purpose of the Study:

• To develop a robust tool for quantifying landfill leachate pollution potential.
• To introduce the revised leachate pollution index (r-LPI).
• To evaluate various aggregation functions for composite indicator development.

Main Methods:

• Utilized the fuzzy Delphi analytic hierarchy process (FDAHP) for index development.
• Selected 11 leachate parameters across three criteria using the fuzzy Delphi method (FDM).
• Employed fuzzy analytic hierarchy process (FAHP) for parameter and criteria weighting, and rating curves for normalization.

Main Results:

• Examined 14 aggregation functions, eliminating 8 based on specific criteria.
• Conducted sensitivity analysis on the remaining six aggregation functions.
• Quantified information loss during parameter aggregation.

Conclusions:

• The weighted additive function was identified as the most effective for quantifying landfill leachate pollution potential.
• The revised leachate pollution index (r-LPI) using the weighted additive function is recommended.
• The developed r-LPI provides a reliable method for assessing leachate pollution.