Evaluation of a petroleum hydrocarbon contaminated site for natural attenuation using ‘RBMNA’ methodology

This paper discusses a recently proposed methodology for risk-based monitored natural attenuation (MNA). The methodology is comprised of three interconnected modules. Module 2, the heart of the procedure, focuses on the fate and transport of the contaminant and its natural attenuation (NA). Computer automated tools are recommended to carry out each step of the methodology. The methodology is used in evaluating a site contaminated by the leaking of an underground fuel storage tank. The study observes that NA is effective at the site; however, it poses onsite risk for the initial 15 years. In order to use MNA as a remediation option, appropriate measures must be taken to reduce this initial risk. This paper offers a comparative evaluation of the two most commonly used NA modeling tools—BIOPLUME-III and BIOSCREEN—in studying the present case.