A new mathematical model for identifying pollution sources in aquifers is presented. The model utilizes Lagrange Constrained Optimization Method (LCOM) and is capable to inversely solve unsteady fluid flow in saturated, heterogeneous, anisotropic confined and/or unconfined aquifers. Throughout the presented model, complete advection-dispersion equation, including the adsorption as well as retardation of contaminant, is considered. The well-known finite element method is used to discretize and solve the governing equations. The model verification is implemented using a hypothetical example. Also, the applicability of the developed code is illustrated by the real field problem of Ramhormoz aquifer in southwestern Iran.

Kardeh basin in Karst terrian situated in koppet dag zone. The lime and carbonate stones existing in karst forms have severely been broken up and there are crevices. As karst drainage system is highly sensitive to transference or arrival of any kind of pollutants, the existence of pollutants such as accumulation of garbage, animal excrements, the flow of setliements sewages to rivers, and trash accumulated by tourists can be potential pollutants for karst water sources. Despite the fact that karst water supplies are used in the northern hills of Mashhad, there have not been protective measures, and karst water sources lack management. It is, therefore; imperative to take protetive and managerial measure in order to control and safe guard water sources. This article is aimed at dealing with karst characteristics and kardeh geomorpholical situation in relation to drainage sensitivity, and pollutant factors which have largely been increased in recent years. These factors have been identified and classified in the region, and their concentration situation is drawn in a map, which can be of importance for executives and planners.

In this study, 41 villages of Sabzevar were selected through cluster sampling. The chlorination quality drinking water in these rural areas was the main concern of the study. Also, the technicians knowledge concerning the proper ways of chlorination and chlorometery before and after a training course was evaluated. The results indicated that the present status of chlorination in rural areas was not satisfactory, and only in 10% of the samples, the remaining amount of chlorine after chlorometery could be considered optimal. As for the second concern of the study, the results revealed that the technicians were vaguely informed about the chlorination process; 40% of them could not even figure out the whole capacity of the reservoirs; 90% were unaware of the variable chlorine requirement. The remaining amount of chlorine after chlorination improved from 78% to 25% after the training course.

Background and Objective: Species of Aeromonas are gram negative, facultative anaerobic and opportunistic pathogens that are found in water system. In this study aimed was performed to determine of Aeromonas prevalence in water sources and water supply Network in Qom.Materials and Methods: 150 samples of water sources which were derived from 15 khordad barrier and other urban water sources during 6 months from April 2009 to September 2009 by memberane filteration in particular environment with presence of amplicilin dextrin agar with vancomycin, were taken under evaluation.Results: Culture experiments and Determination of biochemical showed that only in 20 samples to 15 khordad barrier were positive for presumptive Areomonas with an average count 9 CFU/100ml water sample and the most of isolates belonged to the A. hydrophila, A. veronii biovar sobria and A. sobria species. Antibiotic Sensitivity test and tolerance evaluation of NaCl and cl presented some differences compared with E.coli and vibro that Aeromonas comparing with E.coli and vibro are less tolerant than NaCl (max 3%) and cl (max (37.5ppm) but more tolerant observed with antibiotics include ampicilin, erythromycin, amoxycilin, nalidixic acid, tetracycline and trimetoprim.Conclusion: The low abundance of bacteria in the water can be attributed to high chlorine residual (Average 8/0 ppm) and relatively high percentage of minerals and salt water network Qom.

Rivers are one of the most valuable aquatic ecosystems that their physiochemical properties and the biology of their organisms have strong interactions. One of the major rivers in Iran, which covers a variety of ecosystems, is called Tajan River. In this research, the effect of different pollution sources on water quality of this water body was investigated. Samples were collected in seven different sampling seasons (with three week intervals), which had been selected based on agricultural activities in the study area. The levels of nitrate, nitrite, phosphate, ammonia, dissolved oxygen, hardness, alkalinity, pH and BOD5 were measured. The results showed that the concentrations of phosphate and ammonia were much higher than the global standards for river environments. High levels of alkalinity and hardness observed in this river can be useful for the ecosystem health. The levels of other parameters were within or lower than the global standards. However, BOD5 showed higher levels than these standards in some stations.