---

Farmers in the Indus basin, Pakistan have generally switched to groundwater for additional water supplies due to the irregular supply of irrigation water; currently over 50% of the agricultural land in the basin is at least partially irrigated by tube-wells. These wells pump fresh groundwater, which essentially is the result of massive leakage from irrigation canals into the originally saltwater aquifer since the inception of modern irrigation around 1870. Resalinization of the aquifer now threatens long-term prospects of this new groundwater resource. Since building new dams has become ever more complicated, water resources planning now focuses on sustainable conjunctive use of surface and ground waters. The paper evaluates the raising of the Mangla dam, its effects on long-term groundwater balance and water-logging using an irrigation-economic model. It suggests guidelines to optimize the surface and sub-surface reservoirs by considering the farmers' action in response to government policies. Recently the Government of Pakistan decided to raise the height of the Mangla dam to substantially increase the storage capacity of the basin. This decision was based on basin-wide modelling of conjunctive use by using the General Algebraic Modelling System (GAMS)-based Indus Basin Model Revised (IBMR), which was updated for this purpose in 2000 and supplied with new data in 2002. The results of the analysis reinforced the decision to raise the dam height by 9 m instead of 12 m, which would increase water availability by 68% in the basin. One of the objectives of raising the dam height was to increase the sustainability of beneficial groundwater use in the basin by saving about 2 km3/a of groundwater abstractions.

---

Floodwater spreading (FWS) for the artificial recharge of groundwater (ARG), is an easy and economical method of desertification control. An integrated approach to desertification control based on FWS for the ARG was adopted in the Gareh Bygone Plain in southern Iran. Deposition of the suspended load (SL), carried by floodwater into the sedimentation hasins and infiltration ponds, stabilizes the drifting sand and reclaims the eroded rangeland on which the ARG projects are executed. Results of some of the physical and chemical analyses performed on the one to four-year-old sediment samples obtained from the first three sedimentation basins at the Gareh Bygone Plain ARG scheme show that of the 19 factors analyzed, only two changed significantly due to the settlement of the SL in the basins: sand content decreased by 7.9 and 3.8% at the 0-10 and 0-30 cm depth respectively; and the ESP increased by 17.2% at the 0-30 cm depth. Regression equations were developed correlating soil content of organic matter, total N,P, saturation percentage and CEC with silt + clay content. These relationships indicate the geological origin of N and perhaps P and the importance of SL in the fertility status of the drifting sand.

---

The objective of this study was to classify the Shoosh Aquifer to several zones with different water quality in Khuzestan Province, Iran. In this regard, the performance of classification methods (Discriminant function and Cluster analysis) for the classification of groundwater based on the level of pollution with an emphasis on the problem of over-fitting in training data were considered. An over-fitted model will generally have poor predictiveperformance, as it can exaggerate minor fluctuations in the data. Cluster Analysis(CA) was adopted to spatially explain the similarity of sampling stations with respect to measured parameters. Three methods for variable selection were used including regularized discriminant analysis, principal component analysis and Wilks's lambda method. The best algorithm for variable selection was Wilks'lambda which resulted in reducing the generalization error of the test sample to 0.1 for leave-one-out and 4-fold cross-validation. The second best performed algorithm was regularized discriminant function with 0.167 and 0.133 misclassification error for the two above-mentioned methods, respectively. Principal component analysis did not proved to be a promising algorithm for variable selection in the classification methods.

---

Iran is geographically located in the dry belt of the earth and this has led to a natural shortage of water. Isfahan province in the center of the country with a long-term average annual rainfall of about 150 mm is also severely limited water resources. Regardless of this, for about half a century, due to various reasons, water consumption in this province, which is mainly due to the establishment of large national industries and their chains, as well as agricultural development and population growth and urbanization, water consumption has increased greatly and lack the appropriateness of water resources and consumption has increased over time. Out of 35 plains of the province, 27 plains are forbidden or critically forbidden. Since no effective practical action has been taken to control this situation, various consumers have tried to compensate part of this mismatch by digging deep and semi-deep wells, both legally and illegally, using underground resources. The lack of replacement of groundwater aquifers and the continuous decline of their water level have caused the phenomenon of subsidence and their permanent destruction, so that even if there are sufficient water resources, these aquifers are no longer able to hold water. This causes the destruction of the most important foundation of the life in subsidence areas, which is the water sources, to be lost forever, which has many environmental, human and political consequences. Currently, subsidence threatens many parts of the province's infrastructure, such as national communication infrastructure such as Shahreza Road near Mahyar, Meshkat Road near Kashan, Bandar Abbas-Tehran Railway near Zavareh, Isfahan-Shiraz Railway near Mahyar and Marvdasht. Isfahan airport as well as other industrial, religious and historical infrastructures such as industrial towns of the province (Jafarabad industrial town of Kashan, Aran and Bidgol); Religious and tourist places (Imamzadeh Agha Ali Abbas, Naqsh Jahan Complex, and historical stairs of the province); Public places Naghsh 11 bsidence is spreading in almost all areas of Isfahan province, which threatens the survival of the province in various dimensions and it is necessary to think of serious practical measures in this area.

---

Background: Global warming and climate change are widely indicated as important phenomena in the 21st century that cause serious impacts on the global water resources. Changes in temperature, precipitation and evaporation are occurring in regions throughout the world, resulting in changes including, runoff, streamflow and groundwater regimes, reduced water quantity and quality.
Materials and Methods: Relying upon thirty years of base data (1965–1994), three global circulation models (GCM), namely GISS, GFDM and CCC, are utilized to assess impact of climate change to groundwater recharge rates between years 2010 to 2050 for the Guelph region of the Grand River Basin in Canada. The resulting groundwater recharge rates for alternative soil layers are used to assess water balance conditions, and ultimately, the percolation rate to the groundwater using the Visual-HELP model.
Results: While the climate change impact assessment indicates that evaporation will increase and percolation will decrease during summer, increased percolation is indicated in winter due to additional freeze/thaw dimensions of climate change. The net effect is that the impact of climate change, based upon use of GCM models, is expected to increase groundwater recharge rate by 10% on average (7% for CCC, 10.6% for GISS and 12% for GFDM) in future.                                  
Discussion and Conclusions: According to the results of this research in the Guelph region, the monthly average percolation rate is higher with climate change; (i) the percolation rate is increased during winter due to freeze/thaw effects, while (ii) it is decreased during summer due to higher evaporation rate.

---

Nitrogen deficiency ranks right behind water shortage as the second-most constraint to crop production in the coarse-loamy sand of the Gareh Bygone Plain (GBP) in southern Iran. Since better resource utilization is essential for wise energy management, contrary to reported cases, surface water pollution by N maybe a boon in the GBP. The Agha Jari Formation (AJF), in which the Bisheh Zard Basin (BZB) has been formed, contains an-omalously high concentrations of NO3 and NH4+ in its calcareous sandstone, siltstone and marl components. As about 60% of our irrigation water is supplied through under-ground resources and are heavily over-exploited, the artificial recharge of groundwater (ARG) is actively pursued in Iran. Therefore, a major proportion of the ephemeral dis-charge of the BZB is spread over 1365 hectares of sedimentation basins and recharge ponds of the ARG system in the GBP. These basins and ponds are covered with improved rangeland, and eucalyptus (Eucalyptus spp.) and acacia (Acacia spp.) plantations. There-fore, it is expected that some of the geological-N dissolved in floodwater, and also carried by the suspended load, will reach the groundwater and supply the plants coming in con-tact with the water and/or sediment. Moreover, as both NO3 and NH4+ are considered pollutants of groundwater, the relative abundance of each should be determined, so that possible remedial measures can be designed and implemented. To study the origin of N in the BZB, and to investigate the fate of the dissolved and adsorbed N as it travels from the watershed to the root zone, 13 rock samples, 5 floodwater samples and 81 soil samples were collected and analyzed for NO3and NH4+. The NO3-N concentration was lower than that of NH4+-N in most of the samples: 5.1 vs. 9.6 mg kg-1 in rocks, 13.4 vs.17.4 mg L-1 dis-solved in floodwater, 1.3 vs.4.3 mg kg-1 carried by the suspended load, and 10.6 vs.15.5 mg kg-1 in the 0-125 cm soil profile. Assuming that the mean annual inflow of the GBP-ARG system is 7 million m3 ,we receive 89.4±52.4 kg ha-1 yr-1 of NH4+-N and 68.7± 24.6 kg ha-1 yr-1 of NO3-N, of which some furnishes the vegetative cover with N. A part of what remains may reach the watertable after passing through the vadose zone.

---

---

The partial differential equations for water flow and solute transport in a two-dimensional saturated domain are rendered discrete using the finite difference technique; the resulting system of algebraic equations is solved using a dynamic programming (DP) method. The advantage of the DP algorithm is that the problem is converted from solving an algebraic system of order NC(NL-1) NC(NL-1) into one of solving a difference equa-tion of order NCNC over NL-1 steps and involving NL-1 matrix inversions of order NCNC. The accuracy and precision of the solutions are shown by comparing the results with an analytical solution and calculation of mass the balance. In addition, the perform-ance of the DP model was compared with the results of the MOC model developed by US Geological Survey. In all cases, the DP model showed good results with sufficient accu-racy.

---

---

Aims: This study has been done to investigate the hydrogeological drought and groundwater quality changes over the time in Semnan and Damghan plains.
Materials & Methods: In this research, the groundwater level and groundwater quality changes in of these plains has been evaluated using monthly piezometric wells data for April as groundwater-recharging month and October as groundwater-discharging month and six groundwater quality factors including pH, Chloride (Cl^-), Total Dissolved Solids (TDS), Electrical Conductivity (EC), Calcium (Ca²⁺) and Magnesium (Mg²⁺) were considered to determine groundwater quality changes. Groundwater Resource Index (GRI) and Groundwater Quality Index (GQI) were used to determine hydrogeological drought and changes in its quality, respectively, in studied plains from 2004 to 2018.
Findings: The results illustrated that the trends of groundwater level and GRI are decreasing and there is no steady trend for these indices over the studied period and GRI value is totally higher in city surrounding regions in both plains. According to results of GQI, EC and TDS factors have the highest effect on the groundwater quality, respectively, compared to other factors. GQI value is higher in central and northern parts than compared to other parts in Semnan plain, while in Damghan plain, GQI value in central and western parts is higher than eastern parts.
Conclusion: The correlation between GRI and GQI showed positive results in both plain with 0.542 in Semnan and 0.672 in Damghan, which reflects that the groundwater quality changes with groundwater level changes

---

Aims: In the present study, groundwater quality evaluation for drinking and irrigation purposes in Tashk-Bakhtegan and Maharloo basin was investigated using the data from 420 observation wells.
Materials and Methods: To assess the suitability of groundwater in terms of hydrogeochemical parameters including potassium (K⁺), sodium (Na⁺), magnesium (Mg²⁺), calcium (Ca²⁺), chloride (Cl^-), bicarbonate (HCO₃^-), sulfate (SO₄^2-), Electrical conductivity (EC) and total soluble solids (TDS) for 420 monitoring wells in November 2017 (as a dry month) and May 2018 (as a wet month) and to calculate the Drinking Water Quality Index (DWQI) and Irrigation Water Quality Index (IWQI) were used.
Findings: The results showed that groundwater quality for drinking purpose varied widely across the basin, with the average DWQI value increasing from 238.83 in November 2017 to 249.79 in May 2018. IWQI results also indicated that in most areas, especially in the northern and southern parts of the basin, groundwater has moderate, high and severe limitations for agricultural activities in both months. The average value of IWQI increased from 47.67 in November, 2017 to 49.67 in May, 2018, indicating a slight increase in groundwater quality for agricultural use.
Conclusion: According to the obtained results, necessary precautions should be taken for groundwater before using it for different purposes, and the results of this study can be used in the planning and management of groundwater resources.

---

Application of oxygen releasing compounds (ORCs) is considered as a novel method in petroleum hydrocarbon remediation from groundwater. ORCs destroy chemically the contaminant by exposure to water which results in hydroxyl radical generation or biologically remove the pollution by biostimulation of the groundwater native microorganisms aerobically. In the present study, calcium peroxide (CaO₂) nanoparticles were applied to supply the required oxygen for growth and activity of the native microorganisms to consume naphthalene (20 ppm) as a carbon source. Additionally, the effect of CaO₂ content, temperature and pH on the performance of nanoparticles were investigated in the naphthalene removal. The results indicated that the microbial population was sharply increased in the presence of 400 mg/L of nanoparticles and at 30^oC and the contaminant was completely removed after 20 days at neutral pH. Furthermore, naphthalene was 100% remediated from groundwater at pH 3, 7.4 and 12 after 2, 20 and 30 days, respectively. This proved the acceleration of chemical oxidation under the acidic condition. At 15 and 30 ± 0.5 ^oC the contaminant was removed from the media within 15 and 20 days respectively. Meanwhile, only 75% of contaminant was remediated from groundwater within 30 days at 4 ±0.5^oC which was due to the reduction in the biological activity and the chemical reaction rate.

---

Groundwater is of important drinking water resources. The quality of those water resources which are not affected by human activities, is characterized by local geological conditions. The present research was conducted in order to investigate the quality of water resources located in the south of Birjand plain, South Khorasan Province, using mass balance techniques. This research dealt with the quality assessment and the distribution pattern of physico-chemical parameters (anions and cations, pH, EC, TSS, TDS, and TH) in the groundwater resources in the region resulting in indentifying the contamination resources. Also, the origins of anions and cations in the groundwater resources as well as their connection with the geological characteristics of the region were evaluated by employing the mass balance techniques. The water sampling was performed systematically based on the distribution wells over the plain, with regard to the distances, and perpendicular to the topographical lines from the heights toward the lower plains down to the main river, 3 kilometers apart across the plain. In average, one third of whole wells in the study area were selected for sampling. The samples were taken during the end of dry season (October 2010) from 27 wells, 2 Qanats, and 1 spring. The cations (Na +, Ca+2, Mg+2, and K+), anions (HCO- 3 , SO 4 2-     , CO 3 2-     , and Cl-), TSS, TDS, pH, and the total hardness of the water samples were measured in the Water, Soil, and Plant   Laboratory, Kavosh Ab Shargh Khorasan Jonobi Engineering Services Co.   To assess the quality of the water resources in the region, in this research the physicchemical   properties of water samples were compared with ISIRI 1053 to identify the contaminated wells. The hardness of the samples was measured and the water resources types were identified using Piper Diagram. Also, through calculating the correlation factors and mass balance, hydrogeochemistry of water resources and probable origin of cations and anions were assessed. The results showed that 50%, 30%, and 10% of the groundwater resources are contaminated with magnesium, sodium, and chloride respectively. The petrological studies verified the presence of ophiolite sequence. A set of ultramafic rocks and basic magma (spilites) with wide developments in southern heights of Birjand plain which had the most effects on the water quality of the region. The water resources contaminations in the region may be due to the presence of listonites from the alteration of ultramafic rocks existed in highlands, upstream of the groundwater resources. 96% of groundwater resources are classified as very hard water. The types of groundwater vary from carbonated calcic in highlands to chloride sodic in downstream and east of the region due to high solubility of Na + and Cl- existing in the soil. %36.6 of water resources were chloric-sodic and the rest were classified as chloric-magnesic, bicarbonatesodic, and bicarbonate-magnesic. The correlation analysis of the parameters indicated that sodium has a very high correlation with chloride, potassium, and sulfate. The positive correlation of Mg 2+ with Ca2+ (+0.614) is an indication of the same origin for both ions. Also, EC with TH (+0.710) and Ca 2+ (+0.710) and TH with TSS (+0.641) show positive correlation. In general, these positive correlations indicate the common geogenic origin of cations and anions in water resources of the region. WATEVAL software was employed for calculating the mass balance using the concentration of anions and cations to find the effective parameters and origin of ions in the water resources. These calculations verify and emphasize on the influence of geological conditions of the region on hydrogeochemical properties of water resources of the plain. Mass balance analysis denotes that the origin of sodium and potassium could be the ion exchange process originated from weathering of mafic rocks (spilites) while the calcium may be released due to weathering of plagioclases of sub-volcanic mass, ferromagnesian minerals, carbonated listonite, and dissolution of limestone in the region.  

---

The complex behavior of the aquifer system is studied by solving a set of governing equations using either analytical or numerical methods. Numerical techniques like finite difference method (FDM) is being used to solve differential equation in some simple cases. Recently Meshless methods are developed in engineering fields. They are used for solving differential equations in both simple and complex cases. As this methods needs no meshing or re-meshing on the domain the shortages of meshing disappeared. Less studies already performed in groundwater flow modeling with meshless method. In this study Meshless local Petrov-Galerkin with moving least squares approximation function and spline weight function is used to model groundwater flow in Birjand unconfined aquifer in steady condition. The computed surface of groundwater with meshless local Petrov-Galerkin method is compared with the results observation. The results are found satisfactory. The relative mean error and root mean square error of computed groundwater surface from Meshless Local Petrov-Galerkin are 0.0002 and 0.483 respectively.

---

When groundwater is contaminated, removal of contaminants and the restoration of quality may be slow and sometimes, impractical. It can be harmful for human health, the ecosystem and can result in water shortage. Thus, simulation of contaminant transport can be an important task in hydro-environmental studies and consequently, it is necessary to develop the robust models which can determine the temporal forecast of pollution. For temporal modeling groundwater level and contaminant concentration (GLCC), several computational methods, namely, finite difference method, finite volume method, finite element method and boundary element method have been applied for numerical solution of governing physical-based partial differential equation (PDE). Although the physical-based numerical technique are widely used for temporal and/or spatial modeling of systems, some real-world conditions such as anisotropy and heterogeneity can have meaningful impacts on GLCC and restrict the usefulness of such methods. As a result, these method may be replaced by other techniques. In situation where there is no sufficient field data and output accuracy is preferred over perception of phenomena, a data-driven or black box model can be proper subsided. The uncertainty and complexity of the groundwater process have caused data-driven models such as artificial neural networks (ANNs) and adaptive neuro-fuzzy inference system (ANFIS) are widely used by hydrogeologists. Several studies have been performed to examine the susceptibility of artificial intelligence (AI) models for GFCT modeling. Wavelet transform coherence (WTC) is a technique for examination the localized correlation coefficient and their phase lag between non-stationary time series as a function of both time-frequency spaces. Furthermore, the cross-wavelet power is indicated as high common power of two time series and is found in time-frequency space by cross wavelet transform (XWT). Specifically, XWT investigates the regions in time-frequency space with large common power about a consistent phase relationship, and accordingly suggestion for causality between and time series. On the other hand, the WTC explores the regions in time-frequency apace in which and time series co-vary, but not essentially with high power. So, while analyzing two time series for evaluating both causality and local co-variance, the WTC is more suitable. In order to examine the applicability of the proposed AI-meshless model in real world conditions, the contaminant transport problem in Miandoab plain located in the northwest of Iran was considered as the case study. Miandoab plain, is located in a delta region of Zarrineh and Simineh Rivers. Urmia Lake in north of Miandoab plain, the largest salt-water lake in the Middle East, has been experienced climate change in early 2 decades. The wavelet transform coherence used in this study can be considered as a novel method for spatial clustering of piezometers, for detecting the interaction of aquifers in the plain and relationship between water level of the lake and GLs and CCs of piezometers located near the lake shore witch can present helpful information in GL and CC modeling. The results showed that the efficiency of ANFIS model was more than ANN model up to 30%. Reliability of ANFIS model is more than ANN model in both calibration and verification stages duo to the efficiency of fuzzy concept to overcome the uncertainties of the phenomenon.

---

Steady population growth resulted in increasing the land prices which lead to construction of deep excavation. Therefore the use of underground spaces is economically acceptable. One of the most important issues in the design of underground spaces and deep foundation pits is the existence of groundwater and how to control it. The influence of groundwater on a structural project can be very extensive and it may affect the structural design, performance and the total cost of the project significantly. Many problems related to ground water have been observed in excavation sites recently. Those problems have made significant delays in construction process and sometimes lead to significant re-design of the entire operation process. Considering the negative influence of groundwater on the reinforcement system, (e.g. nailing and anchoring) as well as the difficulty of excavation process under wet condition, water must be pumped out from the excavation area. The process of ground water discharge from the construction area which results in lowering the ground water level in that area is called dewatering. Dewatering operation may lead to ground settlement in the vicinity of construction pit which may damage the building. Although the damage due to ground settlement may be negligible, the potential consequences, especially in connection with claims of third parties, requires sufficient attention. In recent years, dewatering and lowering groundwater levels along deep foundation pits subway tunnels in urban environments caused some significant ground subsidence. The mechanism of this type of ground subsidence is that due to water drainage from the soil layers, the hydraulic pressure decreases leading to an increase in the density of the soil and therefore, ground settlement. Dewatering can leads to ground subsidence in different ways where some of them are as: a) removing the finer soil particles from the ground during water pumpage due to a poor pumping performance, b) in the case of dewatering by pumping water from the floor of excavation pit, piping and boiling can reduce the soil strength properties, leading to a failure in the soil mass and c) compaction of the compressible soils or crushable sandy soils due to increasing the effective stress. Some methods such as cut off walls and artificial injection can be used to reduce the ground settlement due to dewatering, but these methods are very time consuming and costly. Furthermore, methods such as artificial injection may have low efficiency and cause environmental effects. Therefore providing a new technique for reducing the dewatering induced ground settlement in less time and cost is necessary. The strategy proposed in this study is to apply a step by step dewatering method, by setting pumping from drainage wells, coincides with the excavation process. For this purpose the PLAXIS2D software is employed as a finite element method to model the settlement due to dewatering. This operation could be applied by modeling two deep foundation pits with the same structures and different groundwater conditions. The proposed step by step method was modeled in this software by estimating the excavation time and coinciding it with water pumping. Step by step dewatering method has some advantages such as reducing the amount of settlement behind the wall and asymmetric ground settlement under adjacent foundation, reducing the amount of water pumping out of the ground, decreasing the Mohr-Coulomb full plastic points in the range of geogrids and reducing the time and cost of dewatering.

---

In the recent decades, water demand has been increased specially in arid and semi-arid areas, led to the over-exploitation of water resources. Groundwater resources are important sources of water supply for domestic, industrial and agricultural consumption. Nowadays, over-exploitation from groundwater resources has increased the pressure on these sources which causes the major environmental damages. In this study, a cooperative game theory model is used to investigate how the cooperation of groundwater resources consumers influences the environmental damage and the benefit of stakeholders. The used model in the present study is developed for investigation of an optimal control problem including the variables of economic, environmental, agronomic, and hydrologic issues. Ant colony optimization method is used to flexible define and solve the simulation-optimization problem of this study which provides an ability to consider an extensive range of objectives and constraints. The results show that how uncontrolled pumping and over-exploitation in each aquifer affect on the stakeholders of the adjacent aquifers. Furthermore, the impacts on aquatic ecosystems are analyzed and presented as environmental damages. The obtained results demonstrate that in different areas, environmental damages are reduced under the coalition and effective cooperation condition among stakeholders and considering the environmental externalities in comparison with status quo. In the recent decades, water demand has been increased specially in arid and semi-arid areas, led to the over-exploitation of water resources. Groundwater resources are important sources of water supply for domestic, industrial and agricultural consumption. Nowadays, over-exploitation from groundwater resources has increased the pressure on these sources which causes the major environmental damages. In this study, a cooperative game theory model is used to investigate how the cooperation of groundwater resources consumers influences the environmental damage and the benefit of stakeholders. The used model in the present study is developed for investigation of an optimal control problem including the variables of economic, environmental, agronomic, and hydrologic issues. Ant colony optimization method is used to flexible define and solve the simulation-optimization problem of this study which provides an ability to consider an extensive range of objectives and constraints. The results show that how uncontrolled pumping and over-exploitation in each aquifer affect on the stakeholders of the adjacent aquifers. Furthermore, the impacts on aquatic ecosystems are analyzed and presented as environmental damages. The obtained results demonstrate that in different areas, environmental damages are reduced under the coalition and effective cooperation condition among stakeholders and considering the environmental externalities in comparison with status quo. In the recent decades, water demand has been increased specially in arid and semi-arid areas, led to the over-exploitation of water resources. Groundwater resources are important sources of water supply for domestic, industrial and agricultural consumption. Nowadays, over-exploitation from groundwater resources has increased the pressure on these sources which causes the major environmental damages. In this study, a cooperative game theory model is used to investigate how the cooperation of groundwater resources consumers influences the environmental damage and the benefit of stakeholders. The used model in the present study is developed for investigation of an optimal control problem including the variables of economic, environmental, agronomic, and hydrologic issues. Ant colony optimization method is used to flexible define and solve the simulation-optimization problem of this study which provides an ability to consider an extensive range of objectives and constraints. The results show that how uncontrolled pumping and over-exploitation in each aquifer affect on the stakeholders of the adjacent aquifers. Furthermore, the impacts on aquatic ecosystems are analyzed and presented as environmental damages. The obtained results demonstrate that in different areas, environmental damages are reduced under the coalition and effective cooperation condition among stakeholders and considering the environmental externalities in comparison with status quo.

---

Underground water is an important source for drinking and agriculture in the worlds. Due to Extraction of these resources and too frequent droughts in recent years the level of resources has been a significant drop. The aim of this study was to investigate the impact of drought on groundwater levels and estimate the time lag of drought in Plain of Darab. To do this, using rainfall data of Darb ghale darab Station and climate index SPI was extracted conditions of drought. And trend by using the Mann - Kendall non-parametric test was analysis. Then hydrograph of ground water level from 71 to 89 years by using the arithmetic mean of 42 wells was plotted. Finally, by using Mann - Kendall test, trend of 19-year ground water level data of the study area was given analysis. The results indicate that the region Experience of drought during this time and rainfall has been decreased. Analysis of 42 wells showed that the decline in groundwater levels in 40 wells has increased and two other wells, one of them had fixed trend, and other has been reduced in the drop rate. And results of correlation in precipitation data and drop in Groundwater Level showed that the decline in groundwater levels than precipitation occurs with 5 months lag.

---

Fresh vegetables are important sources of nutrients, vitamins and fiber and their consumption, especially in raw form, has increased in recent years due to special attention to improving the health of society. Today, despite the use of strict disinfection methods in vegetable and salad factories, The problem of microbial contamination, especially Escherichia coli mesophilic bacteria, remains in the summer. The aim of this study was to investigate the possibility of interstitial contamination of vegetables with coliforms and specifically Escherichia coli. In this study, iceberg lettuce and non-disinfected vegetable samples were used as control samples and 4 samples of disinfected lettuce and vegetables were randomly sampled from the production line. Samples were inoculated into the relevant culture medium after disinfection with peracetic acid solution and calcium hypochlorite and then final rinsing with water. To evaluate the surface contamination, after 1, 5 and 20 minutes and also to examine the interstitial contamination Finely chopped face After 20 minutes, a specific test for Escherichia coli was performed. The growth of this bacterium was observed in control samples and very finely chopped vegetable samples. The results of this study indicate the accuracy and adequacy of the disinfection process and the lack of surface contamination and the possibility of interstitial contamination and absorption of this bacterium through the roots and vessels of the plant.

---

Tackling environmental hazards has always been one of the main concerns of the country is responsible for program planners. Unfortunately, due to the risks of the operation and less attention is gradual subsidence due to increased exploitation of Aquifers in recent years, learned to be a common problem accordingly. This study evaluates the possibility of subsidence phenomenon possible dangers it as a threat to human projects within the study adhered Kermanshah Plain. The statistics used for this study, 22 of 65 wells using geographic information system maps for the drop in water was prepared. The area that was chosen by the loss of water and geologic logs wells studies to identify the range of sensitivity maps were studied sediment deposits were prepared creating subsidence phenomenon. Finally, using the fuzzy model in GIS software, each layering sensitivity deposits fall in water level set membership, using overlapping gamma phase map sensitivity of the phenomenon of subsidence in 3 classes' sensitivity of large, moderate and low was preparation. The above map shows that the risk of subsidence phenomenon eastern city of Kermanshah in the southern village of Deh pahn that the drop in groundwater is high, the fine-grained sediments are higher than elsewhere in the region.