نشریه زمین شناسی محیط زیست
پیاپی 26 (بهار 1393)

Solid waste excretion is one of the problems of urbanization. The last element obligated the waste management system and the final destiny all wastes should be discarded is bury. Engineering buried sanitary landfill method of waste disposal in land، is to prevent harm to the environment. Landfills in the case of non-compliance with engineering principles، the ability to create very high pollution in the environment، groundwater، surface water and soil. that is have concerned authorities and the public. One of the major landfill pollution، the infecting is caused by the movement of leachate and groundwater contamination. In the design and management of landfills، leachate control، body construction، drainage channels design، is one of the most important factors. Control and reduce the permeability of the landfill is critical environmental factors. To reduce the permeability of the landfill body used geomembranes، clay layers and other impermeable materials. In this study، the effects of added nanoparticles of clay to landfill body soil to reduced permeability has been investigated. This study located in the Bonab city of East Azarbaijan. The results show that adding 3% to 9% clay nanoparticles caused a significant reduction in soil permeability of landfill body. So that the soil permeability reduced from 3. 25×10-6 to 4. 22× 10-7 centimeter per second in normal leachate conditions. In acidic leachate conditions soil permeability reduced from 3. 83×10-6 to 7. 20× 10-7 centimeter per second and in alkaline or basic leachate conditions from 2. 76×10-6 to 2. 02× 10-7 centimeter per second. Thus، the addition of clay and clay nanoparticles significantly reduce the permeability of landfill body to passing leachate.

In this paper try to evaluate the factors effective in instability of the lower Siahbisheh dam wall in the dam left and rghit bank in terms of the slope sliding potential and the solutions to stabilization of the dam wall considering the technical and economic considerations as well as the present limitations. With this aim in view, in the first step the field inspections were made and the important terrain features and tectonic elements were identified, and after collecting the existing set of subsurface information, in order to determining the depth expansion of the sliding mass, the displacement of sliding mass was identified using data resulting from the exploratory soil borings (sondage) having been excavated during the dam project studie's procedures. Next, the geomechanical parameters of the sliding mass were estimated with suitable accuracy for performing the stability analysis and the final instability analyses of the study area were carried out along profiles. Ultimately, the stability analysis results in different conditions: reservoir rapid water drawdown loading, gravity load, the earthquake conditions and the presence of water pressure were evaluated. The results showed that in all sections during loading of rapid drawdown of the reservoir water, the safety factors of the slope will be less than 1 which is indicative of inevitable failure of the slope. Methods of soil excavation and embankment upstream and downstream of the sliding mass and the sliding mass and consolidate choice was offered. Excavation and embankment operations performed in this way, at least according to the calculated maximum volume soil works is left bank.

When the tunnel passes through the weak and different soil conditions, the soil between the tunnel and the surface of the ground move. And the development of these movements to the surface of the ground will be accompanied with the subsidence of the surface structures. Therefore in order to do necessary planning to create supports considering the conditions of the location of doing the project, providing a decision making model is essential in choosing an appropriate option for tunnel supports in planning phase and designing the tunnel project. The aim of this paper is to offer a useful design to specify and choose suitable options for Karaj subway tunnel supports, as a good model for later stages use. This pattern is formed on the basis of technical, financial, administrating, social and effective factors on the site of doing the project by noticing a variety of criteria. The final goal is selecting the most suitable option aimed all the probable options for choosing subway tunnel supports system and noticing effective and important criteria on which basis and by using multi-criteria decision making and new research methods during the operation, proper options are prioritize and ultimately the best ones are chosen. In AHP and TOPSIS methods, alternative (D) NATM method is selected as the best alternative for support system. On the other hand the results taken by numerical modeling with PLAXIS software shown that alternative D is the best support system with 26mm displacement and 10mm subsidence in the section.

Today, the most applied way to access underground in Iran and the world is digging water wells. In addition to exploit advantages, pumping wells have always have several problems such as degradation and instability of their structure, reducing the discharge, forming masses of sand clogging and loss of equipment. According to current statistics, 60% of deep wells drilled in the Kohgiluyeh have a shelf life less than 4 years. The high costs of drilling deep wells and geological sensitivity and degradation and successive failure of wells, deep wells need to study about effective life and affective Factors on wells destruction and preventive methods and appropriate utilization of wells would be inevitable. A sample of 18 wells in the area was used for chemical analysis and preparing and grading tests. Laboratory and field studies and available information, the main causes of destruction and instability of wells in the studied zone were detected as poor design of wells, thin layers of granulated in saturated layer, use of screens with inappropriate size and pores and excessive removal and fouling.

Sand production is defined as the extraction of amounts of fine grain sand and silt while drilling and exploitations of wells. This phenomenon has resulted in quantity, quality, engineering, and environmental problems within parts of the country. The villages of Islamshahr province are among such regions within the country which have been facing this problem in recent years. The goal of this study is to introduce this issue and to explore the reasons, and quantify sand production in 10 fresh water wells within the villages of Islamshahrprovince. In this respect, according to the measurements made within five consecutive cycles in a day(starting point, one, four, eight, and twelve hours) using well head facilities from 1stBahman 1389 untillAban 1390, during which it was proved that HassanabadKhalese, Malekabad, and Shatereh villages located in the southern part of the province do exhibit fine grain sediments which as with the start of pumping and after 4 hours, the sand production reduces; however after 12 hours of the starting point, sand production increases. Although within the northern, and north western regions of Islamshahr province (for instance Ahmadabad Mostofi, FiroozBahram, and Goldasteh,…) which exhibit coarse sediments, as the starting point and after four hours, sand production deemed to be major while after 12 hours of pumping, this amount decreases. Therefore it is recommended to reduce sand production by use of the natural well developments based on proper leaching, pumping tests using controlled motor cycles, artificial development including the implementation of sandy gravel pack, and double gravel pack, along with dual layering of wells, and application of polymer pipes, and sieving filters.

Heavy metals fixation in-situ by using inorganic amendments, is a method for remediation of polluted soils. The goal of this research is to determine 5 kinds of amendments feeiciency for heavy metals fixation of waste-water-irrigated soils in around of Tabriz city and to suggeste the best amendment/amendments. solutions containing CD, Pb< Cu, Ni, and Zn were added to 0.5 gram of 5 amendments including calcite, hematite, zeolite, illite, and bentonite; and 10 soil samples from around of Tabriz city. After shaking, these 5 element concentrations were determined in filtered solution by using atomic absorption instrument. Retention capacity percentages of these elements were ca;culated and by using dankan method, the best amendments were determined. There were sharp differnences of heavy metals retention between amendments. Calcite had the highest retention of Cd, ni, and Zn; hematite the highest one of Cu and Pb; and the least one was for ilite. Calciye, zeolite, bentonite, and hematite had significant (in 5 % level) higher retention capacities of Cd, Ni, and Zn in compared to 10 the soil samples. The highest retention capacities was done by calcite and hematite (without significant differences) for Pb. Calcite hematite, and zeolite had the highest retention of Cu. However, the highest retention was done by illite with significant difference with other 2 amendments. The retention capacities of calcite and hematite amendments for the 5 elements were higher than all 10 the soil samples in 5 % level and can cause low uptake and accumulation of these elements in agricultural crops of polluted soils of around of Tabriz city.

Contamination of soil and crops, including leafy vegetables consumed by heavy metals due to improper management of farming systems in the world, human society has provided a cause of concern. In this research, sampling from 10 farms for the study of heavy metals in leafy vegetables including lettuce (Lactuca sativa), spinach (Spinacia oleracea) and parsley (Petroselinum crispum) has been done. In order to perform the sampling of leafy vegetables at the end of each field season 5 randomly sampled from the beginning, end and middle of each plot were harvested and then each field contamination by heavy metals has been studied. The results showed that the effect of heavy metals treatment was significant on leafy vegetables. Mean comparison showed that the highest Pb (0.17 mg/kg), Hg (0.02 mg/kg) and Cd (0.13 mg/kg) in Spinach and highest Ni (0.10 mg/kg) was achieved Lettuce. Also, the lowest Pb (0.11mg/kg) and Cd (0.10 mg/kg) in Lettuce, Ni (0.08 mg/kg) in Parsley and finally Hg heavy metal (0.02mg/kg) was lowest in Lettuce and Parsley.