10.2190/U5QR-X43L-KLHQ-W47H U5QRX43LKLHQW47H 6 Difficulties in Determining Allowable Maximum Daily Pollutant Loads to Waterways Under PL 92-500 167 178 20020509 20020509 20020509 20020509 U5QRX43LKLHQW47H.pdf http://baywood.metapress.com/link.asp?target=contribution&id=U5QRX43LKLHQW47H 2 Steven Pacenka George H. Nieswand Department of Environmental Engineering, Cornell University Department of Environmental Resources, Cook College, Rutgers University The legal background for water-quality-derived effluent limitations and total allowable maximum daily polluting loads under PL 92-500 is reviewed. Sophisticated techniques are often required to implement these provisions of the law. Nevertheless, the shortcomings of some techniques and the lack of experience with their use may lead to challenge of their results by those affected. Dissolved oxygen models for streams are dissected as an example of technical shortcomings. Recommended are the support of explicit and probabilistic accounts for the uncertainty of such models' predictions and standardized rules from the Federal government for making the conservative assumptions required by the law when uncertainty is present. U. S. Environmental Protection Agency, <i>Guidelines for the Preparation of Water Quality Management Plans</i>, 1974. D. A. Rickert, W. G. Hines, and S. W. McKenzie, Methods and Data Requirements for River Quality Assessments, <i>Water Resources Bulletin, 11</i>:2, 1975. R. W. Abendt, Models in Water Quality Planning, <i>Ecological Modeling, 1</i>:3, 1975. H. W. Streeter and E. B. Phelps, A Study of the Pollution and Natural Purification of the Ohio River, <i>U. S. Public Health Service Bulletin</i>, No. 146, 1925. W. E. Dobbins, BOD and Oxygen Relationships in Streams, <i>Journal of the Sanitary Engineering Division, A. S. C. E., 90</i>:SA3, 1964. S. L. Yu, Uncertainties in Water Quality Monitoring: The Case of Atmospheric Reaeration, <i>Proceedings, International Symposium on Uncertainties in Hydrologic and Water Resources Systems, III</i>, Tucson, Arizona, 1972. R. E. Rathburn, Reaeration Coefficients in Streams-State of the Art, <i>Journal of the Hydraulics Division, A. S. C. E., 103</i>:HY4, 1977. V. Kothandaraman and B. B. Ewing, A Probabilistic Analysis of Dissolved Oxygen-Biochemical Oxygen Demand Relationships on Streams, <i>Journal of the Water Pollution Control Federation, 41</i>:2, Part 2, 1969. L. G. Rich, <i>Environmental Systems Engineering</i>, McGraw-Hill, New York, 1973. R. V. Thomann, <i>Systems Analysis and Water Quality Management</i>, Environmental Research and Applications, New York, 1972. G. E. Hutchinson, <i>A Treatise in Limnology</i>, Vol. I, John Wiley & Sons, New York, 1957. D. J. O'Connor, R. V. Thomann, and D. M. DiToro, <i>Dynamic Water Quality Forecasting and Management</i>, U. S. Environmental Protection Agency Research Report No. EPA-660-3-73-009. J. W. Bulkley, Probably Models of Wastewater Treatment Plant Operation, <i>Journal of Hydrology, 28</i>:1, 1976. B. J. Adams and R. S. Gemmell, <i>Water Quality Evaluation of Regionalized Wastewater Systems</i>, Water Resources Center, University of Illinois at Urbana-Champaign, Report UILU-WRC-0070, 1973. J. Cirello, Transfer of NH₄-N from Benthal Deposits and NO₃-N Losses of Overlying Waters of the Upper Passaic River, Ph.D. dissertation, Rutgers University, New Brunswick, New Jersey, 1975. R. P. Thayer and R. G. Krutchkoff, Stochastic Model for BOD and DO in Streams, <i>Journal of the Sanitary Engineering Division, A. S. C. E., 93</i>:SA3, 1967. W. F. Brutsaert, Water Quality Modeling by Monte Carlo Simulation, <i>Water Resources Bulletin, 11</i>:2, 1975. C. S. Shih, Stochastic Water Quality Control by Simulation, <i>Water Resources Bulletin, 11</i>:2, 1975. S. J. Burges and D. P. Lettenmaier, Probabilistic Methods in Stream Quality Management, <i>Water Resources Bulletin, 11</i>:1, 1975.