Tidal fluctuations in a leaky confined coastal aquifer are damped significantly due to leakage into an overlying phreatic aquifer. Jiao and Tang [1999] presented an analytical solution to a simple model describing this phenomenon. Their solution assumes that the tidal fluctuations in the overlying phreatic aquifer are negligible (i.e., a static phreatic aquifer). Here we examine dynamic effects...

A USGS investigation into the transport of contaminants to public-supply wells (PSWs) in four distinctly different aquifers demonstrates how differences in the chemistry of water produced by PSWs and nearby monitoring wells can reveal where and how contamination-susceptible water enters PSWs. This knowledge can be translated into improved monitoring strategies and protection plans. Samples were...

Intermontane basins in the Trans-Pecos region of westernmost Texas and northern Chihuahua, Mexico, are target areas for disposal of interstate municipal sludge and have been identified as possible disposal sites for low-level radioactive waste. Understanding ground water movement within and between these basins is needed to assess potential contaminant fate and movement. Four associated basin a...

Compaction is a mechanical process in which an earthen material is made more dense. The densification occurs as a direct result of the mechanical loading, and is essentially complete at the end of the loading. Volume changes are incurred as a result of a reduction in the quantity of air voids— water content remaining constant. Since it is impractical to squeeze out all the air, the as-compacted...

Analytical studies are carried out to investigate groundwater head changes in a coastal aquifer system in response to tidal fluctuations. The system consists of an unconfined aquifer, a semi-confined aquifer and a semi-permeable confining unit between them. An exact analytical solution is derived to investigate the influences of both leakage and storage of the semi-permeable layer on the tide-i...

introduction more than 90% of drinking water in cities around the world and about 40% of the agricultural water supply from groundwater resources.,thus, groundwater quality consideration issue is inevitable . one of the most important parameter which can show the quality of drinking water is nitrate concentration. nitrate enters the groundwater and surface water through the decomposition of hum...

the aim of this study was to introduce modified continuous wave compaction (mcwc) technique and compare its obturation quality with that of lateral compaction (lc), warm vertical compaction (wvc) and continuous wave compaction techniques (cwc). the obturation time was also compared among the four techniques.sixty-four single-rooted teeth with 0-5° root canal curve and 64 artificially created ro...

The aquifer thermal energy storage system (ATES) owing to growing demands for sustainable energy has become a popular technology in last few decades for long term storing of excess thermal energy. The efficiency of such a system depends entirely on the capacity of the aquifer to retain heat and hence modeling the heat transfer and transient temperature distribution in the aquifer due to hot wat...

This thesis explores speleogenesis within the Dartry Limestone Formation of Cuilcagh Mountain by considering the hydrogeology of the aquifer in the modern setting but also by considering its evolution since it was deposited during Asbian (Dinantian) times. Due to the synclinal structure of the region, which gently plunges northwestwards, the aquifer remains buried beneath the upland and is not ...