The author evaluated the applicability of the Environmental Protection Agency's Organic Leachate Model to wastes containing organic solvents and other organic compounds ("non-solvents"), and determined that the model tends to overestimate the leaching of organic solvents and other organic compounds. Furthermore, when evaluated for its ability to predict leaching of organic compounds, the model was found to predict the leaching of organic solvent compounds with some accuracy, with a correlation coefficient (R²) of 0.671 for this subset of the data. The model's ability to predict the leaching of non-solvent organic compounds, however, was found to be poor, yielding an R² of 0.388 for this subset of the data. The author also investigated the effect that organic solvents have on the leaching of other organic compounds in a waste and found that the presence of solvents increases the potential for leaching among the non-solvent compounds. This conclusion was drawn when the average "leachability ratio", or the ratio of leachate concentration to waste concentration for non-solvent compounds in solvent-bearing waste was found to be nearly four times the average leachability ratio for non-solvent compounds in wastes that did not contain organic solvents. Finally, the author modified the Organic Leachate Model to account for the unique properties of organic solvents in an effort to improve the model's accuracy in predicting the leaching of solvents and other compounds in solvent-bearing wastes. The results of this modelling effort produced an improvement in the predictive ability of the model for both solvents and non·solvents, yielding correlation coefficients (R²) of 0.678 for the subset of data represented by organic solvents, and 0.431 for non-solvents) but the improvement was still not sufficient to justify applying the model to non-solvent compounds. / Master of Science