Hydrologic

Level gauging has existed at least as long as written history markings on the walls of Egyptian temples show that as early as 3000 years ago humans tracked the level of water for hydrologic data. These nilometers are some of the first recorded uses of systems to measure level (1). 

Relevant hydrological fundamentals are utilized (21) to take account of the complex interaction of physical and chemical processes involving sod or rock, water, and contaminant. Attention is paid to uncertainties in calculated results. 

One of the first complete, continuous simulation models was the pesticide mnoff transport model (PRT) (56). Improvements in the PRT modelled to the hydrologic simulation program—FORTRAN model (57). A number of other models have been developed (58,59). These models represent a compromise between the avadable data and the abiHty to encompass a wide range in soils, climates, and pesticides. These models have had mixed success when extended beyond the data with which they were caHbrated. No model has yet been developed that can be proven to give accurate predictions of... 

W. Majewski and D. C. Miller, eds.. Predicting Effects of Power Plant Once-Through Cooling on Aquatic Systems, Technical Papers in Hydrology 20, United Nations Educational, Scientific and Cultural Organization (Unesco), Paris, 1979. 

The efficiency of the weathering of rocks in using carbonic acid produced in the carbon cycle is affected by various hydrologic, environmental, and cultural controls. The fact that the principal anion in fresh surface water worldwide almost always is bicarbonate attests to the overriding importance of this process. Exceptions are systems in which evaporite minerals are available for dissolution by groundwater or where human activities are major sources of sulfate or chloride inflow. 

Sulfate concentration in streams and changes over time are discussed later in this article as one of the principal indices of human influences on stream water composition. Also, it will be shown that differences and similarities ia sulfate yields help in attaining a reasonable perspective on the importance of various hydrologic and geochemical characteristics of individual drainage systems. 

R. A. Smith and R. B. Alexander, Evidencefor Acid-Precipitation Induced Trends in Stream Chemistry at Hydrologic Bench-Mark Stations, E.S. Geological Survey... 

In hydrological studies, the transfer of water between reservoirs is of primary interest. The magnitudes of the main reservoirs and fluxes (volume per time) are given in Figure 7. The oceans hold ca 76% of all the earth s water. Most of the remainder, ie, ca 21%, is contained in pores of sediments and in sedimentary rocks. A Httle more than 1% (or 73% of freshwater) is locked up in ice. The other freshwater reservoir of significant size is groundwater. Lakes, rivers, and the atmosphere hold a surprisingly small fraction of the earth s water. 

Fig. 7. The principal reservoirs in the hydrological cycle R, reservoirs in units of 10 metric tons (10 km ) E, fluxes in units of 10 km /yr T, residence time, yr. R/F = volume /input—output. Fluxes (flows) are approximate. For range of estimates, see Ref. 8.

As emphasized by Postel and co-workers (9), only freshwater flowing through the solar-powered hydrological cycle is renewable (Fig. 7). 

Water is omnipresent on the earth. Constant circulation of water from the ocean to the atmosphere (evaporation) and from the atmosphere to land and the oceans (precipitation, mnoff, etc) is generally known as the hydrologic cycle (see Fig. 1) (1 2). Within the hydrologic cycHc, there are several minor and local subcycles where water is used and returned to the environment. 

The principal hydrologic parameters involved in the storage and transport of freshwater were studied as early as 1894 and are summarized in Table 1... 

Surface-water hydrology The local surface-water hydrology of the area is important in estahhshing the existing natural drainage and runoff characteristics that must he considered. Other conditions of flooding must also he identified. 

Depression method. At locations where natural or artificial depressions exist, it is often possible to use them effectively for land-filling operations. Canyons, ravines, dty borrow pits, and quarries have oeen used for this purpose. The techniques to place and compact solid wastes in depression landfills vary with the geometiy of the site, the characteristics of the cover material, the hydrology and geology of the site, and access of the site. 

Solid-wa.ste-filling plan. The specific method of filling will depend on the characteristics of the site, such as the amount of available cover material, the topography, and local hydrology and geology. To assess future development plans, it will be necessary to prepare a detailed plan for the layout of the individual solid-waste cells. On the basis of the characteristics of the site or the method of operation (e.g., gas recovery), it may be necessaiy to incorporate special features for the control of the movement of gases and leachate from the landfill. 

Proximity to critical areas specified in government regulations, accessihiUty, site geology and hydrology. 

The process related to the paint shop does not impose a significant pollution load on the environment compared to many other industrial activities. It is, however, essential that all possible aspects of environmental pollution by wastewater, environmental hydrology, environmental hydraulics and pneumatics, air, solid waste, noise and hazardous wastes etc. are reviewed to control any kind of pollution within the prescribed limits. Otherwise subsequent tragedies, if caused by environmental negligence in the industrial processes, may lead to the formation of stricter environmental laws. 

E Parent, P Hubert, B Bobee, I Miquel, eds. Statistical and Bayesian Methods in Hydrological Sciences. Pans UNESCO Press, 1998. 

Existing hydrologic literature Existing hydrologic literature... 

Determine interception points Existing site data, hydrologic for withdrawal options, areas literature site inspection of capping... 

INHECl is a front-end to the HEC-1 model developed by Hydrologic Engineering Center. 

Assists in modeling a watershed and creating the inputs to HEC-1 for hydrologic simulations. 

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