Factoring Site Age in Evaluation of Groundwater-Contamination Hazard Rating of Abandoned Municipal Solid-Waste Landfill Sites

A time-dependent system for evaluating the groundwater-contamination hazard rating of uncontrolled municipal solid-waste landfills has been reported elsewhere. While prioritizing uncontrolled landfills for remedial actions, this system (TD-HARAS) accords equal importance to the groundwater contamination caused by a landfill in the past and the contamination to be caused in the future. Some policymakers may like to remediate first those landfills that have greater potential for future contamination; landfill age then becomes an important factor to be taken into consideration for landfill prioritization. In this note, the mathematical framework of TD-HARAS has been extended to allow differential importance to past and future contaminations and to incorporate site age in the assessment of the groundwater-contamination hazard rating of landfill sites. A sensitivity analysis of the extended system (ETD-HARAS) shows that the groundwater-contamination hazard rating of a landfill site decreases with increases in ...