This study aims at evaluating the improved facultative ponds performance in pilot scale. Wastewater has been collected from primary settling basins of Ahvaz wastewater treatment plant. Treatment efficacy of the four systems (three systems in parallel with a control system) has been evaluated over a period of 12 months at various hydraulic retention times (HRT) and organic loading rates (OLR). There has been no baffle and no attached growth media (AGM) in the control system (S0), while other three systems (S2, S3, and S4) have been equipped with different numbers of baffles and AGM packages, containing the mineral shells. Results show that efficiency of BOD5 removal for S0, S2, S3, and S4 are 53.4%, 60.8%, 64.7%, and 67.6%, respectively, while for COD these rates alter to 28.1%, 37.7%, 45.8%, and 50.1 % and of coliform to 66.7%, 76.6%, 80.7%, and 83.4%. Filtered BOD5 in the effluent of S0, S2, S3, and S4 is 32.5, 27.6, 24.6, and 22.3 mg/l, respectively and 60.2, 52.1, 47, and 44.3 mg/l for TSS. Also the 10-day HRT has been optimum among applied HRTs. As such, attached growth-baffled ponds function better than conventional ones, making the technique, examined in the present paper a low-cost process to establish new wastewater treatment plants or upgrading the existent WSPs, especially in case of warm areas of southwestern Iran.

The annual exposure to indoor radon and thoron imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive of indoor radon and thoron concentrations that were carried out in Rohilkhand region with health risk to the dwellers in the region.  In present study, Solid State Nuclear Track Detectors (SSNTDS ) based twin chamber dosimeter with LR-115 track detector were used for estimating Radon (222Rn) and Thoron (220Rn) gas concentration levels in the dwellings of Moradabad city. The average Radon and thoron concentration levels in the studied dwellings were found to vary from 13.5 to 21.8 Bq m-3 and thoron concentrations is found to vary from 11.7 to 19.5 Bqm-3 and its corresponding geometric mean of equilibrium-equivalent 222Rn and 220Rn concentration were found 7.07 to 1.7 Bqm-3 . The total annual effective dose due to the exposure to radon and thoron was found to vary from3.7 to 6.2 mSv/y whereas from thoron found to vary from 0.3 to 0.61 mSv/y.

The aim of this study is to develop analytical solutions for one-dimensional advection-dispersion equation in a semi-infinite heterogeneous porous medium. The geological formation is initially not solute free. The nature of pollutants and porous medium are considered non-reactive. Dispersion coefficient is considered squarely proportional to the seepage velocity where as seepage velocity is considered linearly spatially dependent. Varying type input condition for multiple point sources of arbitrary time-dependent emission rate pattern is considered at origin. Concentration gradient is considered zero at infinity. A new space variable is introduced by a transformation to reduce the variable coefficients of the advection-dispersion equation into constant coefficients. Laplace Transform Technique is applied to obtain the analytical solutions of governing transport equation. Obtain results are shown graphically for various parameter and value on the dispersion coefficient and seepage velocity. The developed analytical solutions may help as a useful tool for evaluating the aquifer concentration at any position and time.

Predicting the quality of water and air is a particular challenge for forecasting systems that support them. In order to represent the small-scale phenomena, a high-resolution model needs accurate capture of air and sea circulations, significant for forecasting environmental pollution. Data assimilation is one of the state of the art methods to be used for this purpose. Due to the importance of thermal structure in monitoring the variations of environmental phenomena, the present study has used Sea Surface Temperature (SST) in data assimilation method to optimize this parameter. SST is one of the most important factors to conduct researches on the ocean, the atmosphere, and their interaction, not to mention monitoring and forecasting air and ocean phenomena as well as commercial and fishing communities and weather forecasts. This study has aimed to present a satellite-derived SST based on pathfinder advanced very high resolution radiometer (AVHRR) data assimilating in FVCOM (finite volume community ocean model) on the Persian Gulf to examine the effect of data assimilation by using the Cressman scheme. The performance of this method has been compared to the optimal interpolation SST (OISST) data, via both visual comparisons and statistical parameters. Applying assimilation method improves correlation coefficient of the model from 0.92 to 0.99. Results demonstrate that the modeled SST has been completely reconstructed by the data assimilated experiment via the Cressman scheme for this region. The spatial and temporal pattern of SST reveals a significant improvement in the entire domain during the investigated period in the gulf.

The present study investigates the accumulation of vanadium, iron, and nickel in different depths of soil in collection sites of oil sludge, in Masjed Soleyman Oil and Gas Exploitation Company, located in Choob Sorkh Region. To conduct the research, four sampling points have been selected at the mentioned site, with one sampling point chosen outside the site, as the clean area. Soil sampling has been carried out at depths of 50 and 100 cm, using an auger. All samples are measured to evaluate heavy metals, according to the standard method of Inductive Coupled Plasma (ICP) spectroscopy. The parameters of pH, EC, density, and organic compounds have also been measured. Results have shown that EC, TOM, and density of the soil in the collection site of oil sludge were relatively higher than the reference site. In addition, statistical analysis has shown that electrical conductivity and organic compounds were influenced by the discharge of oil sludge. The mean concentrations of Ni, V, and Fe in both depths (50 cm and 100 cm) of the four studied plots were 68.8 mg/kg, 46.3 mg/kg, and 53565 mg/kg, respectively, indicating that Ni concentration is more than the acceptable limits in the soil. Although, the amounts of V (36.3 mg/kg), Ni (62 mg/kg), and Fe (19416 mg/kg) in the reference site were lower than the studied oil sludge accumulation site. Thus the study area is a place for the accumulation of oil sludge, since the high concentration of heavy metals can be attributed to human interference.

The present paper has examined the degrading ability of phenol-oxidizing bacterium, Ralstonia eutropha, for biological removal of methylene blue (MB) from aqueous solutions under aerobic conditions. Results show that MB has been extensively eliminated as a co-metabolism in the presence of supplementary carbon (glucose) and nitrogen (yeast extract and peptone) sources and the experimental observations indicate that MB is initially adsorbed on the cell’s surface, in accordance to Langmuir Theory, then to be degraded by the cell. The type of nitrogen source, initial pH, aeration rate, and the presence of CaCl2 are all influential factors in the process of MB removal. The biodegradation kinetics modeling has determined that while playing an uncompetitive role, MB inhibits its biodegradation at high concentrations. According to the best fit Han-Levenspiel Model, the maximum MB specific biodegradation rate (rmax), half-saturation concentration of MB (KS), maximum allowable MB concentration (Sm), and the shape factors (n and m) have been 7.37 mg gcell-1 h-1, 32.13 mg/L, 158.8 mg/L, 0.27, and 0.76, respectively.

The present study has been conducted to assess the surface water quality of Halda River from September 2015 to March 2016. DO, BOD5, COD, pH, EC, Chloride, Alkalinity, and Hardness concentrations in water samples have been found to range within 0.93-5.15 mg/L, 30-545 mg/L, 43-983 mg/L, 6.3-7.3, 110-524 uS/cm, 12-56 mg/L, 35-67 mg/L, and 38-121 mg/L, respectively. Multivariate statistical analyses, such as Principal Component Analysis (PCA) as well as Correlation Matrix (CM) have revealed significant anthropogenic pollutant intrusions in water. Cluster Analysis (CA) has indicated decent results of rendering three different groups of resemblance between the two sampling sites, reflecting the different water quality indicators of the river system. A very strong positive linear relation has been found between COD and BOD (1.000), hardness and EC (0.993), pH and DO (0.979), hardness and COD (0.929), hardness and BOD (0.924), EC and COD (0.922), and EC and BOD (0.916) at a significance level of 0.01, proving their common origin entirely from industrial effluents, municipal wastes, and agricultural activities. River Pollution Index (RPI) has indicated that the water from rivers at Kalurghat and Modhunaghat varied from low to high pollution, which is due to the former area's being mostly industrial zone with some domestic sewage, while the latter underwent less industrial activities. On the contrary, lots of agricultural activities have been found in Modhunaghat. Use of river water can pose serious problems to human health and aquatic ecosystem via biological food chain. The present research suggests special preference for proper management of the river with eco-friendly automation along with development of the country's sustainable economic.

The present study is aimed at characterizing the landfill leachate as well as its impact on the surrounding groundwater in Kolkata, India. Landfill leachate has been seasonally characterized from 2012-2014, indicating the landfill site in methanogenic phase with high contamination of organics, nutrients, salts, and heavy metals. Sixty groundwater samples have been analyzed for twenty two physico-chemical parameters in pre-monsoon, monsoon, and post-monsoon season of 2014. Seasonal alterations of groundwater quality have been evaluated with a statistical tool, Kruskal-Wallis test, to assess the influence of leachate, showing significant changes in almost all its physico-chemical parameters with sampling time. Majority of groundwater samples were contaminated with Hg, Pb, Cd, Cr, Fe, and Mn, indicating very little effect of redox control on the occurrence and transport of heavy metals. Comparison of physico-chemical parameters with World Health Organization (WHO) and Bureau of Indian Standards (BIS) indicate that majority of groundwater samples have been inadequate to use as potable water. Therefore, this study would help in developing policies for landfill leachate treatment programs and controlling groundwater pollution at the concerned landfill site.

Certain species of Hermetia illucens, also known as the Black Soldier Fly(BSF), were found in a compost plant in Roorkee located in Northern India. Its larvae arevoracious eaters of organic waste, hence can play an ecologically-important role in solidwaste management. Morphological analysis of various stages of BSF life cycle by SEMshowed that its body along with its wings is densely covered with hair. The identifiedspecies of BSF were black in color and oviposited into the composted material. The larvaegrew up to 30 mm long in 12 days from an initial length of only 6mm, gaining almost 200%of its initial weight after voraciously feeding on organic waste. The mouth of the H. illucensshowed a well-developed mandibular-maxillary complex that had similar characteristics ofscavengers, making the insect a suitable candidate for organic waste consumption.

In Nigeria irrigated agriculture is an important tool for economic growth, food security, and poverty reduction during dry periods of rain-fed agriculture. The concentration and composition of dissolved constituents in water determines its quality for irrigation use. Water quality studies strongly suggest that agriculture is a leading source of water quality problems, due to pesticides and other agro-inputs, widely used by farmers to improve agricultural productivity. Poor quality irrigation water would therefore obviously affect soil quality and crop productivity. This study was carried out in 2015 to assess the presence of metals and physical properties of water, used for irrigation in Kwara state, Nigeria. Samples were randomly collected from thirty irrigation sources in three senatorial zones of Kwara State. The samples were analyzed for the presence of metals and water quality parameters, using standard procedures. Results showed that the highest concentration of Sulphate (7.0mg/L), Nitrate (8.9mg/L), Sodium (31.6mg/L), Calcium (3.1mg/L), and Magnesium (0.7) ions were within acceptable limits. The Sodium Adsorption Ratio, an indicator for water suitability in agricultural irrigation as well as a standard diagnostic parameter for the sodicity hazard of a soil, was significantly the highest (22.7) in Kwara North. Results of the study point to the need for an effective irrigation water quality assessment to curb nonpoint source pollution that could be caused by improper use of chemicals and pesticides by farmers.