The restoration of meadowland using the pond and plug technique of gully elimination was performed in a 9‐mile segment along Last Chance Creek, Feather River Basin, California, in order to rehabilitate floodplain functions such as mitigating floods, retaining groundwater, and reducing sediment yield associated with bank erosion and to significantly alter the hydrologic regime. However, because the atmospheric and hydrological conditions have evolved over the restoration period, it was difficult to obtain a comprehensible evaluation of the impact of restoration activities by means of field measurements. In this paper, a new use of physically based models for environmental assessment is described. The atmospheric conditions over the sparsely gauged Last Chance Creek watershed (which does not have any precipitation or weather stations) during the combined historical critical dry and wet period (1982–1993) were reconstructed over the whole watershed using the atmospheric fifth‐generation mesoscale model driven with the US National Center for Atmospheric Research and US National Center for Environmental Prediction reanalysis data. Using the downscaled atmospheric data as its input, the watershed environmental hydrology (WEHY) model was applied to this watershed. All physical parameters of the WEHY model were derived from the existing geographic information system and satellite‐driven data sets. By comparing the prerestoration and postrestoration simulation results under the identical atmospheric conditions, a more complete environmental assessment of the restoration project was made. Model results indicate that the flood peak may be reduced by 10–20% during the wet year and the baseflow may be enhanced by 10–20% during the following dry seasons (summer to fall) in the postrestoration condition. The model results also showed that the hydrologic impact of the land management associated with the restoration mitigates bank erosion and sediment discharge during winter storm events. Copyright © 2013 John Wiley & Sons, Ltd.

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Mining operations within the Coeur d'Alene District of northern Idaho have been continuous for over 85 years. Data presented herein demonstrate that early day mining and milling wastes are now affecting the ground‐water quality in several locations. One of the affected areas is the lower Canyon Creek Basin located in the Coeur d'Alene District near Wallace, Idaho. Ground‐water pollution of the Canyon Creek Basin results from leaching of old mine tailings that are intermixed with the upper part of the sand and gravel aquifer. High zinc, lead and cadmium concentrations occur in ground water and soil samples taken from the portion of the sand and gravel aquifer containing old mine tailings. Analysis of water samples from a settling pond located in the upper portion of the study area indicates that the pond water is not the source of the heavy metal concentrations found in the ground water. However, the water from the pond's decanting system provides recharge to ground water and compounds the problem.

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Heat emanating from within the earth is one source of geothermal energy. This vast repository of energy is generated from the decay of natural radioisotopes and heat from the molten core of the earth. Natural sources of geothermal fluids for heating and bathing have been utilized since prehistoric times. The useful applications of hydrothermal resources depend on the temperature of the extracted fluid. Relatively low‐temperature fluids can be effectively applied for purposes such as greenhouse heating, fish farming, and especially space heating. Waters at higher temperatures can be used for a variety of industrial processes and the generation of electricity. Transportation of hot fluid over more than a few kilometers is often economically impractical. It is then possible to apply the power generated by hydrothermal energy in a variety of ways and at distant locations. The efficiency of electrical generation is directly related to the thermal quality of the resource. To successfully compete with the multitude of energy sources available, geothermal energy must be available and retrievable in both a convenient and an economical manner. Conditions have only been met using hydrothermal geothermal resources in the form of hot water and steam, but these particular hydrothermal resources are limited. Most of the world's accessible geothermal energy is found in rock that is hot but contains limited fluid.