Abstract: The contamination of 15 ground water resources
of a selected region earmarked for the emergency supply
of population has been monitored. The resources have been selected
on the basis of previous assessment of natural conditions
and the exploitation of territory in their surroundings and infiltration
area. Two resources out of 15 have been excluded from further
exploitation, because they have not met some of the 72 assessed
hygienic indicators of extended analysis. The remaining 13 resources
have been the subject of health risk analysis in relation
to the contamination by arsenic, lead, cadmium, mercury, nickel and
manganese. The risk analysis proved that all 13 resources meet
health standards with regard to the above mentioned purposefully
selected elements and may thus be included into crisis plans. Water
quality of ground resources may be assessed in the same way
with regard to other contaminants.
Abstract: For stricter drinking water regulations in the future, reducing the humic acid and disinfection byproducts in raw water, namely, trihalomethanes (THMs) and haloacetic acids (HAAs) is worthy for research. To investigate the removal of waterborne organic material using a lab-scale of bio-activated carbon filter under different EBCT, the concentrations of humic acid prepared were 0.01, 0.03, 0.06, 0.12, 0.17, 0.23, and 0.29 mg/L. Then we conducted experiments using a pilot plant with in-field of the serially connected bio-activated carbon filters and hollow fiber membrane processes employed in traditional water purification plants. Results showed under low TOC conditions of humic acid in influent (0.69 to 1.03 mg TOC/L) with an EBCT of 30 min, 40 min, and 50 min, TOC removal rates increases with greater EBCT, attaining about 39 % removal rate. The removal rate of THMs and HAAs by BACF was 54.8 % and 89.0 %, respectively.
Abstract: Drought is one of the most important natural disasters which is probable to occur in all regions with completely different climates and in addition to causing death. It results in many economic losses and social consequences. For this reason. Studying the effects and losses caused by drought which include limitation or shortage of agricultural and drinking water resources. Decreased rainfall and increased evapotranspiration. Limited plant growth and decreased agricultural products. Especially those of dry-farming. Lower levels of surface and ground waters and increased immigrations. Etc. in the country is statistical period (1988-2007) for six stations in Roudbar town were used for statistical analysis and calculating humid and dry years. The dependable rainfall index (DRI) was the main method used in this research. Results showed that during the said statistical period and also during the years 1996-1998 and 2007. more than half of the stations had faced drought. With consideration of the conducted studies. Drawing diagrams and comparing the available data with those of dry and humid years it was found that drought affected agricultural products (e.g.olive) in a way that during the year 1996 1996 drought. Olive groves of Roudbar suffered the greatest damages. Whereupon about 70% of the crops were lost.
Abstract: Drinking water is one of the most valuable resources
available to mankind. The presence of pathogens in drinking water is
highly undesirable. Because of the Lateritic soil, the iron
concentrations were high in ground water. High concentration of iron
and other trace elements could restrict bacterial growth and modify
their metabolic pattern as well. The bacterial growth rate reduced in
the presence of iron in water. This paper presents the results of a
controlled laboratory study conducted to assess the inhibition of
micro-organism (pathogen) in well waters in the presence of
dissolved iron concentrations. Synthetic samples were studied in the
laboratory and the results compared with field samples. Predictive
model for microbial inhibition in the presence of iron is presented. It
was seen that the bore wells, open wells and the field results varied,
probably due to the nature of micro-organism utilizing the iron in
well waters.
Abstract: The contents of nitrates and nitrites were monitored in
15 ground water resources of a selected region earmarked for the
emergency supply of population. The resources have been selected on
the basis of previous assessment of natural conditions and the
exploitation of territory in the infiltration area as well as the
surroundings of water resources. The health risk analysis carried out
in relation to nitrates and nitrites, which were found to be the most
serious water contaminants, proved, that 14 resources met the health
standards in relation to the assessed criterion and could be included in
crisis plans. Water quality of ground resources may be assessed in the
same way with regard to other contaminants.