• Decision Making in a Multiple-use Approach to the Reclamation of Strip-mined Lands

      Goicoechea, Ambroes; Duckstein, Lucien; Fogel, Martin; Department of Systems and Industrial Engineering, University of Arizona, Tucson, AZ 85721; Departments of Systems and Industrial Engineering and Hydrology & Water Resources, University of Arizona, Tucson, AZ 85721; School of Renewable Natural Resources, The University of Arizona, Tucson, AZ 85721 (Arizona-Nevada Academy of Science, 1977-04-16)
      With the advent of ever -increasing energy needs, large-scale surface mining has gained new impetus, and there is much concern about reclaiming the mine spoils to bring about beneficial land uses. This paper presents a decision making algorithm labeled PROTRADE, and a case study of the Black Mesa region in Northern Arizona. PROTRADE considers a set of objective functions, a set of physical constraints, articulates the preferences of the decision maker in a progressive manner, and generates a set of alternative solutions. The decision maker is then able to trade level of achievement, for each objective function, against the probability of achieving that level.
    • Simulation of Summer Rainfall Occurrence in Arizona and New Mexico

      Yakowitz, Sidney; Southwest Watershed Research Center, Agricultural Research Service, Tucson, Arizona; Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona (Arizona-Nevada Academy of Science, 1977-04-16)
      Thunderstorms produce most of the annual rainfall and almost all runoff from arid and semiarid rangelands in the southwest U.S. A model was developed to be used for predicting runoff in river basins, flood plane zonings, estimating flood damage, erosion, and sediment transport, and estimating precipitation available for forage growth. This rainfall occurrence model has three parameters: elevation, latitude and longitude, and takes into account rainfall occurrence in 22 stations located in Arizona and New Mexico. From these variables, mathematical equations were developed in an effort to predict point rainfall occurrence. Estimates of the number of seasonal occurrences were used as a check of the equations within the model.
    • Stochastic Prediction of Sediment Yields from Strip Mine Spoils of the Arid Southwest

      Auernhamer, Mark E.; Fogel, Martin M.; Hekman, Louis H., Jr.; Thames, John L.; School of Renewable Natural Resources, University of Arizona, Tucson (Arizona-Nevada Academy of Science, 1977-04-16)
      Mathematical simulation of the erosion process is accomplished by using a time series of hydrologic parameters as inputs into a modified form of the Universal Soil Loss Equation. A parameter to account for antecedent moisture conditions was found to improve the predictive success of the Universal Soil Loss Equation. The simulation predicts sediment yield resulting from a stochastic sequence of precipitation events on an experimental watershed. This sediment model will be used as a component in a larger, more complex hydrologic simulation model which can be used to determine optimum reclamation practices for the strip mined areas of the arid Southwest. Data from regraded strip mine spoils at the Black Mesa of Arizona are used in calibrating the model.
    • A Utility Criterion for Real-time Reservoir Operation

      Duckstein, Lucien; Krzysztofowicz, Roman; Departments of Systems and Industrial Engineering and Hydrology & Water Resources, University of Arizona, Tucson, AZ 85721; Department of Hydrology and Water Resources, University of Arizona, Tucson 85721 (Arizona-Nevada Academy of Science, 1977-04-16)
      A dual purpose reservoir control problem can logically be modelled as a game against nature. The first purpose of the reservoir is flood control under uncertain inflow, which corresponds to short -range operation (SRO); the second purpose, which the present model imbeds into the first one, is water supply after the flood has receded, and corresponds to long-range operation (LRO). The reservoir manager makes release decisions based on his SRO risk. The trade-offs involved in his decision are described by a utility function, which is constructed within the framework of Keeney's multiattribute utility theory. The underlying assumptions appear to be quite natural for the reservoir control problem. To test the model, an experiment assessing the utility criterion of individuals has been performed; the results tend to confirm the plausibility of the approach. In particular, most individuals appear to have a risk-averse attitude for small floods and a risk-taking attitude for large ones.