Power Plants worldwide are considering conversion from heavy fuel oil to Orimulsion. As a demonstration of screening analysis, the consequences of hypothetical spill scenarios of these two fuels were evaluated and compared using spill modeling. The Spill Impact Model Application SIMAP was run in stochastic mode to determine probabilities and degrees of exposure. In stochastic mode, a large number of simulations are run for a given spill site and fuel release scenario, varying the spill date and time, and thus the environmental conditions, for each run. Outputs of the model were used to (1) generate probabilities that water surface, water column, and shoreline areas would be affected by a release from the given site; (2) determine the highest exposure concentration in time and for any possible environmental condition; and (3) evaluate cumulative exposure at each location around the spill site. The stochastic modeling approach provides an objective, quantitative method for comparing the consequences of the alternate fuels, avoiding the bias of subjectively choosing individual model runs to examine a priori, and providing a distribution of results that may be statistically described. This type of approach is an important advancement in performing ecological risk assessments for spills.

This content is only available as a PDF.