Pumping test is the most reliable method for determining the hydraulic conductivity and tracer test is the most reliable way to determine the hydraulic connection. Pumping test involves imposing a perturbation such as pumping in a well and measuring the response of the aquifer, for example in terms of head variations (Renard et al. 2009). Those data are then interpreted with the help of analytical or numerical models in order to infer the hydraulic properties (hydraulic conductivity, transmissivity and storage coefficient) of the aquifer (Renard et al. 2009).
Tracer tests are frequently used at the regional scale to delineate the difference between the hydrogeologic and topographic ...view middle of the document...
We apply data from a pumping and tracer tests conducted at the dam site of Salman Farsi of Fars province in 1997 and 1996.
The study site is located in Ghir county, Fars province, south of Iran (Fig. 1). This site is located at a distance of 190 km from the city of Shiraz and 30 km from the city of Ghir.
Fig. 1 Location of the dam site of Salman Farsi in Ghir county, Fars province, south of Iran
The site is part of the Asmari formation limestone. The Asmari Formation is divided into three units: Upper, Middle and Lower Asmari (Fig. 2). This formation belongs to the Oligomiocene period. The Upper Asmari outcrops immediately from the upstream of the dam body. This unit is composed of shelly limestone, marl and Marly limestone (Fazeli 2007). The Middle Asmari is composed of limestone, calcarenite, cherty limestone, nomolitic and Oolitic limestone. The dam is situated on this member. Due to its lithology, the karst features (channels, big caverns, chimneys, etc.) have developed in the Middle Asmari (Fazeli 2007). The Lower Asmari is downstream from the dam site. It contains regularly bedded limestone alternating with marls at the top and thin to very thin limestone and Marly layers at the bottom (Fazeli 2007). Pabdeh Formation is downstream of the Lower Asmari. It consists of Marly limestone, shale and marl. The shale and marl deposits make this formation impermeable (Fazeli 2007).
Fig. 2 A plan view of the piezometer locations relative to the pumped well in geology map of dam site of Salman Farsi.
Figure 2 shows a map of the study site. The Hydrogeology of the site is described in Aghili and Meidani (1998) and Fazeli (2007). According to these studies, The Upper and Lower Asmari have low permeability with some marly layers. The Middle Asmari has much more limestone layers, and also the purity of the limestone increases. Limestone is very brittle, so during the tectonic process more fractures were developed in this unit (Fazeli 2007). Also, impervious layer in most borehole is detected during drilling and lugeon test, so the aquifer at dam site of Salman Farsi is a confined aquifer (Aghili and Meidani 1998).
The pumping and tracer tests conducted in the Asmari. In this area, high karstification generally localized around the intersection of faults or discontinuities.
In November 1997, a pumping test was performed at a dam site of Salman Farsi under the authority of Mahab Ghodss consulting engineering company. One pumping well (Well 1) and six observation wells around it were constructed on the site (Fig. 2). The radial distances of the observation wells from the pumping well, and also some of their characteristics have been presented in table 1.
Table 1 Some characteristics of pumping well and piezometers in a dam site of Salman Farsi (Aghili and Meidani 1998).
Borehole UTM Discharge (L/s) Well depth (m) Depth to water table (m) Thickness of the aquifer (m) Distance from P.W.1 (m)
P.W.1 707531.06 3158326.57...