Abstract: ^ digital computer model was used to model an unconfined sandstone aquifer (Arikaree aquifer) in about 340 square miles (880 square kilometers) in southeastern Wyoming. The model was calibrated by comparing observed and calculated changes in the potentiometric surface and leakage from the aquifer along streams during water year 1974. The comparison was fairly good for changes in the potentiometric surface and was good for leakage. The calibrated model was used to predict changes in the potentiometric surface and leakage through water year 1979, assuming no new ground-water development after 1974 and normal recharge to the aquifer. Water-level declines of as much as 14 feet (4.3 meters) were predicted, but much of the area would be relatively unaffected. The total predicted decrease in leakage between water years 1974 and 1979 was about 500 acre-feet (0.6 cubic hectometer) per year; the greatest decrease was predicted along streams closest to areas of pumpage.

From introduction: The primary objective of this study was to determine the net transport of zinc into the study area from urbanized perimeter, out of the study area across the northern boundary of the study area, and across the sediment-water interface within the study area, all within a limited time period. A secondary objective was to assemble as much data on other trace metals--their concentrations and chemical states in water, suspended solids, sediments and interstitial fluids--as possible within the time and funding constraints of the study in order to describe the existing trace metal conditions in the south bay. Thus the bulk of effort was directed toward evaluating the distribution and movements of zinc, but the data collected on the distribution and movements of zinc, but the data collected on the distribution of other metals is important and is reported here.

From abstract: This report presents the theory and method of calculation used by MIX2, describes the input to the program, presents results of two test cases, and provides a program listing.

Abstract: The route of the partly completed Cross-Florida Barge Canal follows the St. Johns, Oklawaha and Withlacoochee Rivers. If the canal is ·completed, the Summit Reach, connecting the Oklawaha and Withlacoochee Rivers will be excavated into the Floridan aquifer. Large springs that discharge from this limestone and dolomite aquifer flow to the Oklawaha and Withlacoochee Rivers.

From introduction: The North Coast Limestone area is one of the two most important ground-water provinces of Puerto Rico--the other being the South Coast Alluvial aquifer. The investigation of the water resources of the South Coast has progressed to the point that at this time (mid-1971) an electric-analog model of the area is being prepared. The hydrology of the North Coast Limestones, however, was never investigated as a whole before this investigation, and, therefore, this study was designed to assess the most important hydrolic features of the area.