Risk Of Surface Water Pollution Research Articles

GIS-based risk assessment of tropical surface water pollution by integrating hydrogeological and anthropogenic parameters

Surface water pollution is a huge issue worldwide that keeps growing in magnitude and complexity which leads to millions of people don’t have access to clean water resource. Numerous studies on vulnerability, hazard and risk assessment of water pollution had been conducted yet most of them only focused on one of the three risk components. Therefore, the objective of this study was to apply a geospatial approach that integrated hydrogeological and anthropogenic parameters to assess the risk of surface water pollution in Selangor River Basin, Malaysia. Analytical Hierarchy Process (AHP) and Weighted Linear Combination (WLC) were applied in hydrogeological vulnerability assessment. WRASTIC index was used in anthropogenic hazard assessment. The risk map showed that high-risk zones were mainly located in areas where development and agricultural activities are extensive. Conversely, low-risk zones were in areas that were mostly covered by forest with few developments, such as the upstream region. The results also revealed that high and very risk levels were dependent on soil media and presence of land use and anthropogenic activity especially agriculture, industry, and wastewater presence. The risk map also showed that developed area with high hydrogeological vulnerability would have higher risk of pollution compared to areas without any anthropogenic hazard. The risk map can assist stakeholders to identify at risk of pollution. This allows for better decision-making in integrated river basin management.

Trace element adsorption from acid mine drainage and mine residues on nanometric hydroxyapatite.

Mining Ag, Cu, Pb, and Zn sulfides by flotation produces great volume of residues, which oxidized through time and release acid solutions. Leachates from tailing heaps are a concern due to the risk of surface water pollution. Hydroxyapatite nanoparticles may remove trace elements from acid leachate collected from an oxidized tailing heap (pH ranged 1.69 ± 0.3 to 2.23 ± 0.16; [SO42-] = 58 ± 0.67 to 60.69 ± 0.39mmol). Based on the batch experiments under standard conditions, the average removal efficiency was 96%, 92%, 86%, and 67% for Cd, Pb, Zn, and Cu, respectively. The Zn adsorption was modeled by the Freundlich equation, but Cd, Cu, and Pb isotherms do not fit to Freundlich nor Lagmuir equations. Adsorption and other mechanisms occur during trace elements removal by hydroxyapatite. In the polymetallic system, trace elements saturate the specific surface of hydroxyapatite in the following order Zn, Cd, Cu, and Pb. The pH values must be higher than 7.5 to adsorb trace elements. The dose of 3.8% of hydroxyapatite to acid mine drainage removed efficiently > 80% of the soluble Fe, Cu, Mn, Zn, Cd, Ni, and Pb: 4020.0, 37.3, 34.8, 432.0, 4.4, 0.7, and 0.11mg L-1 from leachate A and 3357.1, 46.6, 27.8, 569.0, 4.7, 0.6, and 1.7 from leachate B, respectively. The application of 0.7% of hydroxyapatite decreased the extractable Pb in unoxidized tailing heaps from 272 to 100mgkg-1. It is likely to use hydroxyapatite to control trace element mobility from mine residues to surrounding soils and surface water.

Development of a method of assessment of ecological risk of surface water pollution by nitrogen compounds

A method has been developed for quantitative and qualitative assessment of the risk of surface water pollution by nitrogen compounds based on the use of the indicator of the total content of inorganic nitrogen forms in water (Ninorg), that is, This indicator is considered as the sensitivity coefficient kn. The choice of the indicator is dictated by the need to protect waters from pollution caused by nitrogen compounds during their flow from agricultural sources (Directive 91/676 /EU). The experience of developed countries has shown that nitrogen compounds deteriorate the quality of water and prevent the achievement of a "good ecological state" of water bodies. For territories with developed agriculture, it is important to establish environmental risks of damage depending on the degree of nitrogen pollution. Quantitative assessments of environmental risk are provided on the basis of a probabilistic approach. The risk was calculated as the product of the probability of a hazardous event occurring multiplied by the consequences of this event. The consequences of river pollution with nitrogen compounds were assessed as the ratio of the total concentration of nitrogen compounds (sensitivity index kn) to its threshold value (50 mg/dm3 or 11.3 mgN/dm3). In order to develop a scale for qualitative and quantitative risk assessment, relationships were established between the sensitivity indicators kн and the risk indicators R' for individual rivers, and for the study area as a whole, by means of spatio-temporal generalization. The probabilistic characteristics of possible environmental damage were determined on the basis of the obtained regression equations of the form R'=f(kn) and the statistical law of distribution of the risk value R'. The developed method will make it possible to determine the rank of the risk zone and the probability of getting into it, depending on the given sensitivity indicator kn

Risk perception of aquatic pollution originated from chemical industry clusters in the coastal area of Jiangsu province, China.

According to "the Layout Scheme of the Chemical Industry in Jiangsu Province From 2016 to 2030" and "the Development Planning in the Coastal Area of Jiangsu Province, China," several chemical industry clusters will be located in the coastal area of Jiangsu province, China, and the risk of surface water pollution will be inevitably higher in the densely populated region. To get to know the risk acceptance level of the residents near the clusters, public perception was analyzed from the five risk factors: the basic knowledge about the pollution, the negative effects on aquatic environment imposed by the clusters, the positive effects brought by the clusters, the trust of controlling aquatic pollution, and the acceptance of the clusters. Twenty-four statements were screened out to describe the five factors, and about 600 residents were covered in three typical clusters surveyed. On the whole, the youth showed a higher interest on the survey, and middle-aged people were likely to be more concerned about aquatic pollution incident. There was no significant difference on risk perception of the three clusters. The respondents investigated had good knowledge background on aquatic pollution and the residents identified with the benefits brought by the clusters. They were weak in risk awareness of pollution originated from the chemical enterprises' groups. Although the respondents regarded that chemical industry clusters did not expose all points of pollutants' generation to the public, they inclined to trust the administration agencies on controlling the pollution and welcome the construction of chemical clusters in their dwelling cities. Besides, risk perception showed obvious spatial distribution. The closer were the samples' sites to the clusters and the rivers receiving pollutants, the higher were the residents' perceived risk, benefit, and trust. However, there was no identical spatial difference on risk acceptance, which might be comprehensively influenced by various factors. Demographic variables on diverse risk acceptance levels were further illustrated, and some useful conclusions might be provided for managing the response of residents to aquatic pollution and helping identify effective precautionary measures in the vicinity of chemical industry clusters.

Biological nitrogen removal in a modified anoxic/oxic process for piggery wastewater treatment

AbstractPiggery wastewater is characterized by its high ammonium concentration and low COD/nitrogen ratio. The indiscriminate discharge of untreated piggery wastewater from scattered household pig farms has posed a potential risk of surface water pollution in rural areas of southern China. In this study, an anoxic/oxic (A/O) process with elastic fillers tightly packed in each tank was investigated for piggery wastewater treatment. Two anoxic tanks and two aerobic tanks were used in series and the hydraulic retention time of each was 24 h. Dissolved oxygen concentration in the aerobic tanks was intentionally controlled at below 2 mg L–1 for the implementation of nitritation. After sludge acclimation, three recycle ratios from 100 to 300% were tested. More than 90% of organic matter was removed from raw piggery wastewater despite recycle ratio values. However, the NH4+-N concentrations in the effluent slightly increased from 30 to 65 mg L–1 as the recycle ratio increased. Higher recycle ratio benefited the ...

Relative risk of surface water pollution by <I>E. coli</I> derived from faeces of grazing animals compared to slurry application

Relative risk of surface water pollution by <I>E. coli</I> derived from faeces of grazing animals compared to slurry application

Relative risk of surface water pollution by E. coli derived from faeces of grazing animals compared to slurry application

Abstract. This article examines some of the factors that influence the relative risk of Escherichia coli pollution of surface waters from grazing animals compared to cattle slurry application. Drainage water from pipe‐drained plots grazed with sheep (16 sheep + lambs per hectare) from 29 May to 17 July 2002 had average E. coli counts of 11 c.f.u. mL−1 or 0.4% of estimated E. coli inputs over the grazing period. Drainage water from plots on the same site treated with cattle slurry (36 m3ha−1 on 29 May 2002) had lower average E. coli counts of 5 c.f.u. mL−1 or 0.03% of estimated faecal input. Sheep (16 lambs per hectare) grazing under cooler, moister conditions from 24 September to 3 December 2001 gave drainage water with much higher average E. coli counts of 282 c.f.u. mL−1 or 8.2% of estimated input, which is more than twice the average E. coli counts previously reported under such conditions (Vinten et al. 2002 Soil Use and Management 18, 1–9). Laboratory studies of runoff from soil slabs after slurry application showed that the mobility of E. coli in surface soil decreased with time, suggesting that increased attachment to soil or migration to ‘immobile’ water also provides at least part of the physical explanation for the relatively higher risk of pollution from grazing animals compared with slurry. Sampling for E. coli in field drainflow and in streamwater during a storm event in the predominantly dairy Cessnock Water catchment, Ayrshire, Scotland supported the hypothesis that E. coli transport is linked to grazing animals. For a 7‐mm rainfall event, roughly 14% of the estimated daily input from grazing livestock was transported to the river, even though little slurry spreading had occurred in the catchment in the previous month. Spot sampling of field drains in grazed fields and silage fields in the same catchment also showed that grazing animals were the principal source of E. coli and faecal streptococci.

Toxic risk of surface water pollution—six years of experience

Assessment of an ecological quality of surface water is necessary for effective protection, abatement and successive revitalisation of river ecosystems. This quality is primarily given by biological impact of surface water pollution. Substances contained in pollution are frequently toxic to aquatic organisms. Risk of chronic impact of surface water pollution is very often underestimated due to hidden long time action of pollutants. Proper estimation of the risk is not possible from results of chemical analyses and data of substances' toxicity. Chemical analyses are not able to detect all substances presented in water including the products of reactions between them. In addition, a simultaneous presence of substances can modify their final effect on aquatic organisms. Therefore, a complex method of assessment of toxic risk of surface water pollution based on ecotoxicological approach was developed. The toxic risk of surface water pollution is determined from results of evaluation of toxic risk of organic part and inorganic part of surface water pollution. Resultant degree of toxic risk of total pollution is given by the highest degree detected in any part of the water pollution. Presented method, which is routinely used for monitoring in the Czech part of the Odra river basin, was fully standardised and published in the form of the Czech branch technical norm of water management (TNV) in the year 2000.