History and Objectives: Exited sewage following mechanical methods contains pathogenic agents. Therefore, swage clearance with chlorine and other compounds is necessary. It has been reported that in fixation ponds with regard to a long-time standing, there is a high rate of clearance and there is no need of additional clearance and this reduces the costs. Therefore, this study was carried out to determine the clearance rate of FECAL COLIFORMS in fixation ponds of Shoosh sewage refinery in Tehran in 1999. Materials and Methods: The semi-experimental strategy of this study was carried out on integrated stabilization pond in all of the seasons using two feeding sewage methods The system is a combination of anaerobic and facultative ponds and then two high-performance and complementary with a total time of 20 days. Sampling was done every two weeks from inlet and outlet sewage and number of FECAL COLIFORMS was counted and data were analyzed statistically. Results: It was found out that clearance rate of FECAL COLIFORMS was greater in spring than other seasons (99.97%) and was rather great in winter (greater than 99.5%). This indicates the high performance of the system for clearance of pathogenic agents from sewage. Conclusion and Recommendations: It is concluded that combinational tixation ponds have an appropriate performance for clearance of pathogenic agents. Feeding through upward current can increase the performance, as does the facultative pond. It is recommended to carry out more studies in this field.    

Chitosan, as a coagulant is used in water and wastewater treatment. It has similar performance in comparison with other conventional coagulants, and doesn’t have any disadvantages of them. However, its bactericidal property is lower than the metal based coagulants. In this study the potential synergistic effect of potassium permanganate, as a powerful oxidant, on the Chitosan FECAL COLIFORMS inactivation and turbidity removal has been investigated. Synthetic wastewater samples were prepared by mixing tap water with Bentonite and adding pure culture of FECAL COLIFORMS that provided by biological laboratory of Tehran University of Medical Sciences. After preparing synthetic samples of the wastewater and determining its turbidity and FECAL COLIFORMS concentration, various doses of Chitosan and Potassium Permanganate individually and in combination with each other, were injected to the samples. Afterwards supernatant of jar reactors were investigated for turbidity and FECAL COLIFORMS removal. Simultaneous use Chitosan and potassium permanganate has higher removal efficiency than the individual using of them. Highest applied combined dose (3 mg / L Chitosan and 1.5 mg / L potassium permanganate) reduced FECAL coliform to a level less than 100 MPN/100mL, which is equivalent 4 log-inactivation of FECAL COLIFORMS. Simultaneous use of Chitosan and potassium permanganate in tertiary treatment of wastewater can led to produce lower turbidity, as well as higher microbial quality in the effluent, which can reduce the amount of required disinfectant, consequently disinfection by products formation lowered very much.

Background: Constructed wetlands are systems designed based on the utilization of natural processes, including vegetation, soil, and their associated microbial assemblage to assist in treating different types of wastewater. Methods: Two local Appalachian plants (Louis latifolia and Phragmites australis) were planted into smallscale constructed wetlands to treat domestic wastewater in the North of Iran. The influent wastewater and the effluent from each wetland were sampled daily for 120 days. Experiments were conducted based on the mean ± standard deviation (SD) by analysis of variance (ANOVA). Results: It was found that nitrate, phosphate, FECAL and total COLIFORMS were reduced by 84. 4%, 94. 4%, 96. 3%, 93. 9% for P. australis and 73. 3%, 64. 0%, 94. 4%, 92. 1% for L. latifolia, respectively. Conclusion: According to the results, by using the HF-CW technology with L. latifolia and P. australis plants, the treated wastewater fully meets the wastewater discharge parameters of WHO standards.

Water samples of 0, 50, and 100 nephelometric turbidity units (NTU) spiked with FECAL COLIFORMS (107 CFU/ml) were exposed to natural sunshine in 1l quartz glass tubes fitted with rectors’ compound parabolic concentrators CPCS at two forms CPC1 (whit nanoparticle zinc oxide) and CPC2(without nanoparticle zinc oxide). The samples were characterized using the X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscope (TEM). On clear days, the complete inactivation times (more than 7-log unit reduction in bacterial population) in the systems with CPC1, and CPC2 were 15, and 30 min, respectively. The maximum temperatures obtained in the water samples were 80 ° C for CPC1, and 82 ° C for CPC2. The use of CPC1 with hydroxyl radicals (OH• ) production significantly improved the efficiency of the old CPCS technique, since these systems (CPC1-2) shortened the exposure times to solar radiation and also minimized the negative effects of turbidity and also regrowth was zero in the disinfected samples. Due to two simultaneous effects of high temperatures and UV, regrowth in most ways of solar disinfection was not seen in these examples. Overall, this technology has been proved to be a good enhancement method to inactivate microorganisms under real conditions and represents a good alternative technique to drinking water treatment.

Background and Objectives: Qualitative evaluation of sewage sludge before any kind of application is essential. The present study was aimed to investigate Total coliform, FECAL coliform and Salmonella in sewage sludge produced at wastewater treatment plants in Azerbaijan Province, Iran.Materials and Methods: Nine wastewater treatment plants were chosen in East Azerbaijan Province, and their sludge from drying bed was studied. Total COLIFORMS, thermo-tolerant COLIFORMS, and Salmonella spp., were surveyed during winter time, 2015. Total and thermos-tolerant COLIFORMS were enumerated by EPA method 1680 and salmonella was counted using EPA method 1682.Results: In the case of total coliform, sludge sample from Jolfa with 1.82´106 MPN/g showed the highest contamination, while Sarab showed lowest FECAL coliform count with 2.02´103 MPN/g. As in the case for FECAL coliform, the bacteria count for thermo-tolerant COLIFORMS was higher in Jolfa than other cities; on the other hand, Ahar with no FECAL coliform count or less than 2.2 showed the minimum contamination rate to FECAL COLIFORMS. In case of Salmonella spp., sludge samples from Ahar and Bostan Abad did not show any salmonella. While sludge sample from Tabriz wastewater treatment plant was determined as the most contaminant sludge with bacteria count equal to 84 per g. Moreover, sludge sample from Sarab wastewater treatment plant showed the least contamination rate, and bacteria count was 6 per g.Conclusion: From the stand point of microbial quality, all sludge samples met class B standards set by USEPA, while none of them could provide class A standards. Thus, special precautions must be taken in case of soil amendments by the sludge produced from wastewater treatment plants.

Background: This study investigated the interaction between heterotrophic bacteria and coliform, FECAL COLIFORMS, FECAL streptococci bacteria in water supply networks.Methods: This study was conducted during 2013 on water supply distribution network in Aq Qala City, Golestan Province, Northern Iran and standard methods were applied for microbiological analysis. The surface method was applied to test the heterotrophic bacteria and MPN method was used for coliform, FECAL coliform and FECAL streptococci bacteria measurements.Results: In 114 samples, heterotrophic bacteria count were over 500 CFU/ml, which the amount of FECAL coliform, coliform, and FECAL streptococci were 8, 32, and 20 CFU/100 ml, respectively. However, in the other 242 samples, with heterotrophic bacteria count being less than 500 CFU/ml, the amount of FECAL coliform, coliform, and FECAL streptococci was 7, 23, and 11 CFU/100ml, respectively. The relationship between heterotrophic bacteria, COLIFORMS and FECAL streptococci was highly significant (P<0.05). We observed the concentration of COLIFORMS, FECAL streptococci bacteria being high, whenever the concentration of heterotrophic bacteria in the water network systems was high.Conclusion: Interaction between heterotrophic bacteria and coliform, FECAL COLIFORMS, FECAL streptococci bacteria in the Aq Qala City water supply networks was not notable. It can be due to high concentrations of organic carbon, bio-films and nutrients, which are necessary for growth, and survival of all microorganisms.

In this work, the performance of two treatment plants in the City of Mashhad, one with an aerated lagoons system and the other one with waste stabilization ponds system were evaluated in regard to their efficiency in reduction of pathogenic microorganisms. For this purpose, over a period of one year (with 15-days intervals), samples were taken from the influent and effluent (prior to disinfection unit) of the above mentioned treatment plants. The samples then were analyzed for parameters such as temperature, pH, density of total COLIFORMS (TC) and FECAL COLIFORMS (FC), dissolved oxygen and total suspended solids concentration. The results indicated that the aerated lagoons system was much more efficient in removal of indicator bacteria than the waste stabilization ponds during autumn and winter periods. However during the summer months, the waste stabilization ponds showed a higher efficiency in this regard. In general, the waste stabilization ponds system reduced the density of TC and FC by 0.21-2.15 log10 and 0.20-2.33 log10, respectively. In contrast, the levels of reduction in aerated lagoons system were in the range of 0.29-2.03 log10 for TC and 0.42-2.40 log10 for FC. Results indicated that solar intensity, pH and dissolved oxygen concentration were found to be the most significant parameters that reduced the microorganisms population in waste stabilization ponds, While, in the aerated lagoons system, the dissolved oxygen concentration in aerated basin and solar intensity play the most important role. In general, without receiving an adequate disinfection, the effluent from waste stabilization ponds and aerated lagoons cannot provide the microbiological standards required for irrigation of agricultural crops.

The main purpose of the research is to investigate the relationship between pathogenic mirco-organisms (total COLIFORMS (TC) and FECAL COLIFORMS (FC)) with physical and chemical parameters of water in different depths of reservoirs. Samples were taken from different depths of the dam reservoir in June, , July and August, when the water was in maximum temperature, pH, TC, FC, electrical conductivity (EC), pressure (P), Total phosphorus (TP), total dissolved solids (TDS), dissolved oxygen (DO) and temperature (T) were measured. Preliminary results showed that pH, DO and T parameters decreased with increasing depth in the water column, while EC, TDS and TP increased. The results obtained from multivariate statistical analysis methods revealed that TC and FC were affected by P and TDS changes. By moving from the surface to the bottom of the dam reservoir, the distribution of the COLIFORMS decreased, which is unbalanced, and no specific pattern of coliform distribution can be considered. Based on the analysis of the relationships, it was found that 58% of total coliform and 59% of FECAL coliform changes were predictable if the total soluble and pressurized solids were quantified. Also, by Pearson correlation analysis, it was determined that total coliform and FECAL coliform, in none of the four levels, were correlated with total soluble solids and pressure parameters, and none of these parameters had a significant direct effect on them. As a result, FECAL coliform and total coliform are directly related to T, Do and pH and inversely related to EC, TDS, and strain.

The lake in the protected Bakhtegan zone is the shelter to wildlife and very important from an ecological and environmental viewpoint. The lake has a unique diversity in terms of Halophilic and Halotolerant bacteria. Based on our experiments, from among the six genera ofHalobacteriaceae, only the four Halobacterium, Haloarcula, Halococcus, and Haloferax genera were isolated, the greatest frequency (mean: 54%) belonging to Halobacterium and the least frequency (mean: 4%) belonging to Haloferax among the isolated genera. The Halotolerant bacteria isolated included Pseudomonas sp., Flavobacterium sp., Micrococcus sp. and Bacillus sp. genera. The greatest number of Halotolerant bacteria isolated from the lake water was Pseudomonas (mean: 72%). Furthermore, the number of total COLIFORMS was greater than the number of FECAL COLIFORMS. Statistical analysis revealed that Halophilic and Halotolerant colonies had the same mean numbers only at Tashk and Gomban sampling sites but that the mean numbers obtained at Dehzir sampling site was significantly different from those obtained at the former two. It was also found that increasing salt concentration and pH level increased the number of halophilic colonies while increased levels of dissolved oxygen decreased their numbers.Salt concentration, pH level, and DO level had similar effects on the number of total and FECAL coliform colonies.

The aim of this study was to investigate the microbial and physicochemical parameters of Neur Lake water. Five stations (studied stations according to geographical location, water elevation, flows to the lake) were selected. Sampling was done twice in year, once in spring and summer and Autumn 1395. The microbial tests were performed including counting the total number of bacteria, total coliform and FECAL coliform, streptococcus and sulfite Reducing Bacteria. The highest density of heterotrophic bacteria was in summer and at station 1 (50, 000 cfu / ml). The highest levels of FECAL COLIFORMS were at station 1 and 3 (110 cfu / ml) in autumn. The highest incidence of streptococcus was at station 3 (110 cfu / ml) in summer. The highest frequency of sulfite reduction bacteria was at station 1 in the spring at PO4mg / l, NH4mg / l and NO3mg / l in all seasons in the EPA standard. The COD, BOD and pH in some seasons were higher than the standard EPA standard The amount of heterotrophic bacteria, total coliform and streptococus in some seasons and stations was higher than the standard, due to the increase of environment and water temperature, Passing livestock in the region, and some tourist and agricultural activities in the warm seasons. Wind and water turbulence and sediment increase in the autumn were the causes of microbial contamination in Neur Lake. The lake is not desirable for fish species, especially cold water, due to the high parameters of physical and chemical properties of water.