MIP2AM Decision Analytic Approaches for Integrated Risk Management
Monday, 14 November 2005: 8:00 AM - 11:40 AM in 347-348

(STA-1117-553564) Philadelphia Air Toxics Study: Evaluation of Risk Management Options Using MIRA.

Stahl, C.¹, Cimorelli, A.¹, ¹ U.S. EPA Region III, Philadelphia, PA, USA

ABSTRACT- In 1996, EPA identified air toxics of greatest potential population risk nationally. Thirty-two air toxics on the Clean Air Act's list of 188 of toxic air pollutants plus diesel particulate matter were identified. In 2004, EPA began a study in the Philadelphia area to better identify the local air toxics risk. The investigative approach uses a novel "one atmosphere approach" by considering toxic air pollutants together with ozone and fine particulate matter (PM2.5) precursor pollutants and those pollutants affecting haze rather than individually, as EPA has traditionally done. Using the Industrial Source Complex (ISC) model and the Community Multiscale Air Quality (CMAQ) model, the 1996 results were refined and present day risk was examined for 9 pollutants in Philadelphia. These pollutants are: formaldehyde, acetaldehyde, acrolein, 1, 3-butadiene, benzene, chromium, ethylene dichloride, polycyclic organic matter (POM), and diesel particulates. Using the air quality model results as the data inputs for risk, several risk management options are crafted and evaluated using the Multi-criteria Integrated Resource Assessment (MIRA) approach. MIRA is an approach that allows for the transparent organization of data and integration of environmental, social and economic factors and stakeholder values. These risk management options are evaluated using a variety of decision criteria, including air quality risk metrics (inputs from the air quality model), control costs, and emission reductions obtained from existing control programs. In addition, hypothetical emission control programs can be designed and their effectiveness evaluated against decision-maker/stakeholder-derived criteria by using the MIRA approach. Furthermore, the impacts of data uncertainties that might affect how the risk management options are ranked can also be evaluated. This case study is an illustration of how science can be integrated into EPA risk management and policy making.

Key words: Air toxics, decision making, risk management, stakeholders