Effects of Irrigation with Well Water on Chemical Characteristics of a Weakly Alkaline Soil Used as Rice Field

This paper discussed the effects of irrigation with well water on the salinity and pH of a weakly alkaline paddy soil in Fujin of Heilongjiang Province in the north-eastern part of China.It has been found that after seven years the accumulation of total soluble salts did not occur and that the pH of 0～15 cm layer fell down from 7.92～8.30 to 6.76～7.45,and that the content of anion HCO - 3 and its proportion in the total soluble anions have fallen down.Conversion from paddy soil to upland restored the pH of soil,exchangeable sodium,ESR(exchangeable sodium ratio) to their original levels of upland fields respectively.

Effect of Distance of Sanitary Pits on the Microbial and Heavy Metal Levels in Hand Dug Well Water Samples Consumed by People Living in Akwuke, Enugu South Local Government Area of Enugu State

Studies were carried out to assess the effect of distance of sanitary pits on the microbial and heavy metal levels in hand dug well water samples consumed by people living in Akwuke, Enugu South Local government area of Enugu State, using standard biochemical and spectrophotometric analysis. The well water samples were digested with aqua-regia and four heavy metals (Pb, Cd, Cu and Zn) were assayed in the well water samples at sampling distances of 3, 6 and 10 m respectively from the sanitary pits. The range of mean bacterial counts (cfu/g) for the four detected pathogenic bacteria; S. aureus, Klebsiella pnemeoniae, Echerichia coli and Salmonella enteritidis were 83 - 3730, 510 - 870, 50 - 2535 and 240 - 3420 Cfu/g at sampling distances of 3, 6 and 10 m respectively from the sanitary pits. The mean bacteria counts of the four detected pathogenic organisms in the well water sample at sampling distances of 3 and 6 m respectively from the sanitary pits were above the WHO recommended threshold limits for a safe drinking water. The mean bacterial counts of Salmonella enteritidis in the well water samples of sampling distance of 10 m from the sanitary pits was above the WHO recommended permissible limits. At sampling distances of 3, 6 and 10 m from the sanitary pits, the mean range of Pb, Cd, Cu and Zn in the well water samples were, 0.03 - 0.3, 0.02 - 0.05, 0.46 - 1.71 and 1.63 - 7.03 μg/g respectively. The mean levels of Pb and Cd in the well water samples at sampling distances of 3 and 6 m respectively from the sanitary pits were above their respective WHO recommended threshold limits. The mean heavy metals (Cd, Pb, Cu and Zn) in the well water samples at sampling distances of 3, 6, and 10 m respectively from the sanitary pits were statistically significant at p < 0.05.

Alternative Sanitation and Strategic Directives for the Well Water Security in Cotonou (Benin) and Lomé(Togo)

In the coastal cities of West Africa, land use change, rapid population growth, bad sanitation systems and poor environmental governance degrade the quality of groundwater. This study aimed to assess alternative, acceptable, affordable sanitation disposal and practices for groundwater quality rehabilitation in the cities of Cotonou and Lomé. The study was based on the participatory transdisciplinary approach, field surveys, feedback from interactions with stakeholders, experiences of the practitioners and institutional consultations. This multi-stakeholder approach helped to appreciate ecological aspects of sanitation disposal and its implications on water quality improvement. SWOT model was used to analyze the relevance of assessed ecological system. Well water quality is deteriorated by traditional waste management disposal. Ecological sanitation systems are septic tanks on polyethylene, above-ground latrines and phytoremediation technique in the swamp areas. Collected wastes are used for composting and biogas production. Based on the optimist scenario at 2030 horizon, kind success factors of groundwater security are participation of citizens, existence of sanitation market, valorization of the waste by category, low-cost disposal adaptable to the individual, household and neighborhood’s scales. The strategic directions rely on funding and public policies for WASH, ecological sanitation disposal, cultural environment and good sanitation practices for emergence of new sanitation system to secure and sustain well water quality. But the social acceptability of ecological disposal is limited by the society’s multicultural heritage. These findings could help in decision-making concerning urban groundwater quality protection in the African coastal cities.

Effects of Urban Metabolism on the Well Water Quality in Cotonou (Benin) and Lomé(Togo)

Urban metabolism, a process of material, energy and water flows, consumption or transformation in the cities and outflows of wastes, has impacts on the shallow groundwater. This study addressed the relationship between the urban metabolic system and well water physicochemical and bacteriological quality in the coastal cities of Cotonou and Lomé. A participatory transdisciplinary approach, involving non-academics and academics stakeholders was used to analyse urban inflows and outflows related to groundwater quality. Standard methods were used to measure well water quality from 100 seasonal samples. Waste management revealed poor sanitation and hence a linear urban metabolism with no solid and liquid wastes and excreta recycling. This form of city metabolism reinforced by the seawater inflow is the main source of groundwater quality deterioration in Cotonou and Lomé. The principal water types Ca2+–Mg2+–Cl-– SO2-4 (48.21%), Na+–K+–Cl-–SO2-4 (65.9%) and the Gibbs diagram suggested water-rock interactions and dominance of cations exchange on the hydrogeological compositions, also seasonally controlled by saltwater intrusion or anthropogenic salinization. The water quality index on the range of 35.90 to 169.60 in Cotonou and 82.94 to 364.68 in Lomé indicated well water very poor quality to unsuitable for drinking. Moreover, the bacteriological quality was bad due to total coliforms (112 - 1812;1 - 1000 UFC/100 mL respectively in Cotonou and Lomé), Escherichia coli (40 - 780;1 - 112 UFC/100 mL), faecal enterococci/streptococcus (18 - 736;1 - 118 UFC/100 mL). The findings could help to sustain groundwater quality by controlling the pollution sources linked to urban metabolism.

Effect of Distance of Sanitary Pits on the Physicochemical Properties of Hand Dug Well Water Samples Consumed by People Living in Akwuke Community, Enugu South Local Government Area of Enugu State

Studies were carried out to evaluate the effect of distance of sanitary pits on the physicochemical properties of hand-dug well water samples consumed by people living in Akwuke community, Enugu South Local Government Area of Enugu State, using standard analytical procedures and instrumentation. The mean range of pH, turbidity, electrical conductivity, total dissolved solids, nitrate and sulphate in the well water samples at the determined sampling distances of 3, 6 and 10 m from the sanitary pits were 5.9 - 7.24, 1.92 - 6.63 NTU, 122.03 - 303.91 μs/cm, 100.00 - 261.90 mg/L, 1.21 - 4.68 mg/L and 28.89 - 49/61 mg/L respectively. The investigated mean physicochemical parameters of the well water samples were generally observed to increase with decrease in the distance of the well water samples from the sanitary pits. The levels of the determined physicochemical parameter of the well water samples at sampling distances of 3, 6, and 10 m respectively from the sanitary pits were statistically significant. The mean pH values of the well water samples at sampling distances of 3 and 6 m respectively from the sanitary pits were below the WHO recommended threshold limits for safe drinking water. Additionally, the mean values of turbidity and total dissolved solids of the well water samples at a sampling distance of 3 m from the sanitary pits were above the WHO permissible limits. The pH, turbidity and total dissolved solids are some of the most important parameters used in assessing the quality of any water source, therefore, the poor physicochemical properties of well water samples at a sampling distance of 3 m from the sanitary pits could put at severe health risk consumption of this water over a prolonged time. Siting well water at a reasonable far distance (above 10 m) for sanitary pits especially in communities with severe water scarcity would definitely help guarantee access to safe drinking water by rural as well as urban dwellers in Nigeria.

Quality of Well Water Used for Market Gardening from Lendeng Area Located in Common of Rufisque (Senegal)

This study analysis was conducted to know the quality of well water around the market gardening area of Lendeng located in the common of Rufisque Est (Senegal). In this study, six groundwater samples were taken near the Lendeng market gardening area. The physicochemical parameters of water such as pH, temperature, electrical conductivity (EC), calcium (Ca2+), magnesium (Mg2+), potassium (K+), iron (Fe2+), chloride (Cl-), sulfate (SO3-4) and phosphate (PO3-4) were measured. The analysis results obtained show sulphate and phosphate have the highest levels. These results were compared to drinking water standards from the World Health Organization (WHO). The correlation coefficient ANOVA was applied to the test result of the samples. The statistical study showed that the well water in the market gardening area of Lendeng is not polluted.

Characterization and Application of the Makoua Clay in the Chemical and Bacteriological Depollution of Gutter and Well Waters of Brazzaville

In this work, the authors made aquatic filters according to the formulation “clay stabilized at 4% of cement mixed with 4% of kambala sawdust and 10% of white sand” then heated to 1050°C to decontaminate the waters of gutters and wells. The authors carried out geotechnical, geochemical, thermal, infrared spectroscopy, and scanning electron microscopy that analyzed the clay material. Geotechnical analyzes have shown that this material is made up of 22% thin sand, 22% of silt, and 56% of clay with 26 plasticity index. The geochemical analysis showed the presence of trace elements shared out as follows: 3% of alkaline metals, 24% of alkaline earth metals, 46% of transition metals, 10% of metal, 16% of lanthanides, 1% of actinides. The most abundant trace elements are barium (19%), vanadium (12%), chromium (11%) and zinc (9%). The thermal and microscopic analyzes revealed the kaolinitic nature of materials. The chemical depollution studies have shown elimination yields of 50% - 52.38% of sulphates;77.33% - 85.19% of phosphates;34.85% - 88.49% nitrates;91.3 - 100 of sulphides;The removal of bacteriological pollution are 92.8% - 98% of total germs;94% - 97% of total coliform and 95% - 98% of E. coli.

Health Consequences of Acid Rain in South West Sweden——Influence of Acid Well Water on Health and Hair Mineral Pattern

Acid rain leads to loss of essential elements from soils and bedrock, causing an imbalance in especially dug well waters, as essential element concentrations decrease and potentially toxic element concentrations increase. In this study 72 private dug wells from acid regions (pH 7.0) in South-western Sweden. Women, drinking the water for at least 5 years, were interviewed about their health and water and hair samples were collected. The concentrations of about 40 elements in water and hair were analysed, mostly by ICP-MS. The concentrations of essential elements such as Ca, Cr, Mo, Se, K, and SO4 as well as the body’s buffering agent HCO3 were significantly lower in acid than in alkaline water. The median Ca concentration was 6 times lower in acid waters, and also in hair compared to alkaline. Median HCO3 was 14 times lower in acid waters. Mg was similar in both populations, since the Swedish bedrock in general has low Mg content, even so limestone in the alkaline area. The concentrations of especially Ca, Cr, HCO3 and SO4, peaked at pH 7.0 - 8.0, due to precipitation of carbonates and sulphates in alkaline soils and leaching from acid soils. The levels of toxic metals such as Cd and Pb were significantly higher in acid well water. High Cu concentration from pipes, causing especially diarrhoea, is a serious acidification problem. The contribution of essential elements to the daily intake from these well waters, 2 Litres consumption per day, was from 0% to above 30% for some elements, clearly showing that 10%, which is generally predicted, can be exceeded for people with private well waters, as well as provide 0%, which is the case for many acid well waters. Water elements were mirrored in hair, e.g. Ca and Mo. The loss of essential minerals, and increased concentration of toxic elements in acid well water, caused mineral imbalances in the body, as mirrored in hair. Women living in the acid area reported more negative health changes than women in the alkaline district, during the time they had been drinking their well water. The number of reported heart, intestinal, muscle, and skin problems were between 2 and 9 times higher among women drinking acid than alkaline well water.

Effect of various Na/K ratios in low-salinity well water on growth performance and physiological response of Pacific white shrimp Litopenaeus vannamei

To investigate the influence of sodium to potassium(Na/K) ratios on the growth performance and physiological response of the Pacific white shrimp( Litopenaeus vananmei), various concentrations of KCl were added to low-salinity well water(salinity 4) in an 8-week culture trial. Six treatments with Na/K ratios of 60:1, 42:1, 33:1, 23:1, 17:1, and 14:1 were replicated in triplicate. The highest weight-gain rate(3 506±48)% and survival rate(89.38±0.88)% was observed in well water with Na/K ratios of 23:1 and 42:1, respectively, while the feed conversion ratio(1.02±0.01), oxygen consumption, and ammonia-N excretion rate was the lowest in the medium with a Na/K ratio of 23:1. Gill Na +-K +-ATPase activity, as an indicator of osmoregulation, peaked in the treatment where the Na/K ratio was 17:1. The total hemocyte count, respiratory burst, and immune-related enzyme activities(ALP, LSZ, PO, and SOD) of L. vananmei were affected significantly by Na/K ratios( P <0.05). After challenged with Vibrio harveyi, the cumulative mortality of shrimp reared in a Na/K ratio of 23:1(30±14.14)% was significantly lower than the control(75±7.07)%. In conclusion, the addition of K + to low-salinity well water in L. vannamei cultures is feasible. Na/K ratios ranging from 23:1 to 33:1 might improve survival and growth. Immunity and disease resistance are also closely related to the Na/K ratio of the low-salinity well water. The findings may contribute to the development of more efficient K + remediation strategies for L. vananmei culture in low-salinity well water.

Fungal-contaminated grass and well water and sporadic amyotrophic lateral sclerosis

Fungi are important infectious disease-causing agents,but are often overlooked as environmental factors in disease.We review several lines of evidence that point to a potential fungal origin of sporadic amyotrophic lateral sclerosis(ALS),the most common form of motor neurone disease.Approximately 90%cases of ALS are sporadic,and the aetiology of sporadic ALS is still unknown.We have previously postulated that grass or soil-associated fungal infections may be a leading cause of sporadic ALS.Herein we extend this proposal to water-associated fungi.A wide variety of fungi have been reported in drinking water including Acremonium,Alternaria,Aspergillus,Cladosporium,Fusarium,Penicillium and Trichoderma.Some of these are known to produce neurotoxic mycotoxins.Despite this,drinking water is not routinely monitored for fungal contamination.Fungal contamination could explain the close correlation between distribution of well water and cases of sporadic ALS in the United States.We propose several mechanisms by which an opportunistic fungal infection from environmental exposure(to water,soil or plants)can lead to long term neuronal degradation resulting in the hallmarks of ALS.If confirmed,the association between fungal infection and sporadic ALS could lead to novel treatment strategies for this progressive and fatal disease.

Bacteriological Analysis of Well Water Sources in the Bambui Student Residential Area

Majority of the population in the Bambui student residential area depend on wells as their source of water supply. Due to increasing complaints from students after using this well water sources, this study was carried out to examine the microbial quality of well water sources in the Bambui student residential area, Bamenda, Cameroon as a way of safe guarding public health against water borne diseases. Water samples from a total of fifteen wells, covered and uncovered were assessed for their bacteriological quality using the multiple tube fermentation technique to determine the coliform count using the most probable number method. Positive tubes of the presumptive test were further cultured on appropriate solid media. The organisms isolated were further characterized using standard procedures. The result of the study revealed that most of the wells were grossly contaminated with bacteria pathogens such as Klebsiella species (95%), Escherichia coli (52%) and Salmonella typhi (32.5%). Comparatively, the uncovered wells were more contaminated with bacteria pathogens than the covered well. All the water samples except three exceeded the standard limit of the most probable number (MPN) per 100 ml set for untreated drinking water by the World Health Organization. This result highlight the fact that most well water sources in the Bambui student residential area metropolis are not safe microbiologically for drinking without additional treatment such as boiling or disinfection and this could lead to outbreak of water borne diseases. Good and proper environmental and personal hygiene must be maintained especially by the users of these wells to prevent their contamination with bacterial pathogens. Wells should also be properly constructed.

Tidal Response Characteristics of the Well Water Level in the Sichuan-Yunnan Region

In this paper,the long time series data of the well water-level data of 12 wells in the Sichuan and Yunnan area is analyzed by the Baytap-G tidal analysis software,and well water level tidal response characteristic parameters( amplitude ratio and phase change)are extracted. We analyzed the features of the shape and stage change,and characteristic parameters of the tidal response of well water level before and after the earthquakes,which can provide a new method and approach to analyzing the response relationships between well water level and earth tide and barometric pressure. The results show that Luguhu Well and 9 other wells are affected by earth tides,and their well water level amplitude ratios and phases are relatively stable; the Nanxi Well and Dayao Well water level changes are affected by the barometric pressure combined with tide force,and their well water level amplitude ratios and phases are more discrete. The water level amplitude ratios and phases of Jiangyou Well,Luguhu Well and Dongchuan Well are significant to large earthquakes,and the relationship between seismic energy density and water level amplitude ratios and phases of M_2 wave of the three wells are presented.

Assessment of Heavy Metal Concentration in Hand Dug Well Water from Selected Land Uses in Wukari Town, Wukari, Taraba State, Nigeria

Hand dug well water remains the major source of domestic (drinking) water in the city of Wukari. This study was aimed at the assessment of heavy metal concentration in hand dug well water from four land uses of abattoir (A), waste dump site (B), residential (C) and commercial (D) in Wukari Town, Wukari, Taraba State. There are about 76 hand dug wells in the study area and for the purpose of this study. Yamane (1967) sample size technique was adopted. Based on this, 95% confidence level and an error limit of 5% were adopted. Thus, four (4) samples A, B, C and D of hand dug well water purposively drawn from the study area used sterilized bottles. The heavy metals tested for in the water samples include: zinc (Zn), copper (Cu), manganese (Mn), iron (Fe), potassium (K), phosphate, and chromium. The results of the analyses were compared with the NSDWQ*MPL and FEPA (2001) standards. The results shows that the concentration of magnesium and manganese in hand dug well water samples A, B, C and D had higher concentrations than the maximum permissible limits of NSDWQ*MPL and FEPA (2001) standards and the concentration of zinc, copper, iron, potassium, phosphate and chromium in hand dug well water sample A, B, C and D was at different compliance level with NSDWQ*MPL and FEPA (2001) standards. ANOVA (F-ratio) statistics at P_0.05 for variation in heavy metal concentration in hand dug well water from land uses A, B, C and D were insignificant. For now, it can be concluded that hand dug well water in Wukari Town is fit for domestic use, but that efforts should be made to reduce the magnesium and manganese concentration by having control on the anthropogenic factors that lead to such high concentration levels or else, soon this source of water may become unfit for domestic use. It was recommended that aggressive public awareness and enlightenment on possible impacts of hand dug well water pollution from human activities should be embarked upon by relevant agencies.

Evaluation of Corrosion Behaviour of Grey Cast Iron and Low Alloy Steel in Cocoa Liquor and Well Water

Corrosion behaviour of cast iron and low alloy steel in cocoa liquor and well water was investigated. The average weight losses of the specimens were measured using digital weighing balance. The results showed that the weight losses of both cast iron and low alloy steel in both media increases with time. Corrosion rate of cast iron in cocoa liquor increases rapidly with time for up to 336 hours (1000 μm/yr), but in well water the rapid rate of corrosion only lasted up to 187 hours (1160 μm/yr) thereafter it continuously dropping until 264 hours (667 μm/yr) after which it remains constant. Low alloy steel corroded faster in cocoa liquor up to 264 hours (200 μm/yr), whereas the initial rapid corrosion rate only lasted up to 168 hours (180 μm/yr) in well water environment. The results revealed that low alloy steel exhibited better corrosion resistance in both media, with cocoa liquor been more aggressive. Thus, low alloy steel will be a better material for piping and pumping system in cocoa processing industries.

A Discussion on the Generality of Precursor Waves on Well Water Level Records

Taking five underground water level observation wells with high earthquake response capability and located in Shanxi,Hebei and Inner Mongolia as study objects,this paper studies and discusses the generality of precursor waves in well water levels before strong earthquakes. It is indicated that the precursor waves often happen before strong earthquakes,with the ratio of occurrence up to 65% ( 41 /63 ) ; the precursor waves have poor generality in different observation wells,which may be related to the different well-aquifer system of different observation wells and the different source parameters of earthquakes. Compared to the seismic water level fluctuations in a single well,the number of precursor wave times recorded in well water levels before strong earthquakes is slightly less than that of seismic water level fluctuations,with a ratio between 39. 7% and 50. 7%, respectively. The number of observation wells with precursor wave recordings before earthquakes accounts for up to 66. 7% of the total number of observation wells. The precursor wave in well water level records has a certain generality in terms of the number of times recorded and the spatial distribution,except for its manifestation characteristics.

A Preliminary Study on Mechanisms of Well Water Temperature Responses Based on the Modes of Stress Loading

Based on the studies of the predecessors, and contrasting the modes of stress loading with water level and water temperature response characteristics of a well-aquifer system, this paper draws a preliminary conclusion on the mechanisms of water temperature responses in a well caused by three modes of stress loading, i.e. gas escape, heat dispersion and cold water penetration mechanisms for elastic seismic wave stress loading; the fracture seepage mechanism for seismic wave stress loading and the hydrodynamic mechanism for earth tide stress loading and stress-dissipative heat mechanism for long period slow stress loading in the earthquake preparation stage. This paper illustrates the typical observation examples for each mode of stress loading and makes a preliminary study on their mechanisms.

Optimization of the Algorithm for Increasing Injection Rate in Water Injection Wells for Pressure Optimization in P Oilfield

In today’s society, with the continuous growth of energy demand, Bohai Oilfield, as an important offshore oil resource base in China, is facing increasingly severe challenges while contributing to national energy security. In order to improve the quality of water injection in the oilfield and gradually achieve efficient and stable production, Bohai Oilfield has launched a water injection well pressure optimization project, focusing on improving the efficiency and quality of water injection in the water injection wells, in order to achieve the optimal water injection plan. In practical work, P Oilfield continues to promote the development of water injection well pressure optimization projects, emphasizing practical exploration and continuous optimization of work plans. However, during the project implementation process, there were some problems, one of which was that the statistics of cumulative injection volume were not scientific enough, resulting in a more comprehensive and accurate presentation of the actual results of pressure optimization work. In the context of continuous improvement work, after careful analysis and research, P Oilfield has decided to optimize the cumulative injection rate algorithm to guide the oilfield’s water injection work in a more refined way, ensuring sufficient and good water injection, and enhancing the oilfield’s production efficiency and comprehensive competitiveness.

Diagnostic Method and Adaptability Analysis of Multiple Water Breakthroughs in Horizontal Well in Combined Well Pattern

The combined well pattern has been widely used in reservoir development, with a common pattern being a horizontal well in the center for oil production and multiple vertical wells around for water injection. For this type of well pattern, determining the horizontal well is affected by which injection wells, especially when the injecting water breaks through, accurately determining the direction of water inflow will provide an important basis for targeted water well measures. Based on the production performance data of horizontal wells, the semi logarithmic relationship curves of water-oil ratio, derivative water-oil ratio, and cumulative production were used for the first time to determine the breakthrough problem of water injection in the surrounding water injection wells of horizontal wells based on their response characteristics. The adaptability of this method under different influencing factors was analyzed. Introducing the parameter of cumulative production not only preserves the variation trend of the derivative of water-oil ratio with time, but also facilitates the processing of actual production data.

Total Indicative Dose Determination in Water from the North Riviera Well Field of SODECI in Abidjan, Cote d’Ivoire

The Uranium-238 (238U), Thorium-232 (232Th) families and Potassium-40 (40K) are of terrestrial origin and contribute generally to an individual’s external exposure through our presence in this environment. They also contribute to the internal exposure through the ingestion of products and beverages such as water that are close to the earth. The aim of this work is to determine the committed effective dose or Total Indicative Dose (TID) due to gamma radioactivity of the borehole water from the Nord Riviera (NR) well field operated by the Côte d’Ivoire Water Distribution Company (SODECI) for the supply of drinking water to part of the population of Abidjan. In addition, the populations, with their habits, could use these borehole waters directly as drinking water. To this end, water samples from the seven (07) functional boreholes were collected and analyzed on a gamma spectrometry chain, equipped with an HPGe detector in the laboratory of the Radiation Protection Institute (RPI) of the GHANA Atomic Energy Commission (GAEC). The results of the specific activities of 238U, 232Th and 40K obtained were transcribed into TID. As the natural radioactivity of the borehole water is high [1], the TIDs calculated from the activity results of the natural radionuclides238U, 232Th, and 40K vary for the seven boreholes from 0.150 to 0.166 mSv/yr with an average of 0.161 ± 0.034 mSv/yr. The TID of the control tower, where the borehole water is mixed and treated for household use, is equal to 0.136 ± 0.03 mSv/yr. The TIDs obtained are therefore all slightly greater than the WHO reference dose value of 0.1 mSv/yr. But all remain below the UNSCEAR reference dose of 0.29 mSv/yr.