Awareness on usage of contaminated groundwater around Perungudi dumpsite,Tamil Nadu,India

Groundwater is the major drinking water source both in urban and rural area. Mostly in urban and peri-urban areas of developing countries, groundwater is more susceptible to contamination due to urbanization. Therefore, the awareness of usage of groundwater has to be analysed to frame the policy measures and to suggest proper intervention programs. The community residing around Perungudi dumpsite, Tamil Nadu, India, has been chosen to assess the awareness on usage of groundwater using regression model. The groundwater flow and quality analysis assessed technically is in line with people’s perception on groundwater quality. The model results clearly indicate that the socio-economic status (β = 0.167) and distance (β = 0.305) play a major role in groundwater usage. Though 31.2 % of respondents reported that the water quality is bad within 1 km in the contaminated area, 45 % of low socio-economic categories depend on well water. This shows the unawareness of health issues due to the usage of contaminated water. Proper policies have to be framed, especially for the contaminated site to get rid of adverse health impacts due to long-term exposure of contaminated water.     

Monitoring and evaluation of shallow well water quality near a waste disposal site

This study identifies shallow well water contamination sources near the Mae-Hia waste disposal site and the clarification of the extent of well water contamination caused by leachate generated from the disposal site. The water of 40 shallow wells around the Mae-Hia disposal site, where three potential sources of groundwater pollution exist, was sampled and analyzed for physical, chemical, and biological characteristics. Water samples were taken every month from June 1989 to May 1990 along with a measurement of well water levels in order to estimate the groundwater flow direction. Comparison with the drinking water standards/guidelines showed that well water in the study area was not suitable for drinking due to the high contamination of total and fecal coliforms and moderate contamination by nitrate and manganese. It was found that the level of conductivity, total solids, color, chloride, chemical oxygen demand, sodium, copper, and lead in the groundwater of wells located adjacent to the disposal site were higher than in other areas. In addition, higher concentrations of sodium, chloride, calcium, and magnesium in the wells located downstream of the groundwater flow were recorded. Estimation of a leachate plume using chloride as an indicator showed that the wells located in the eastern part of the disposal site, a dominant direction of groundwater flow, were contaminated by leachate generated from the waste disposal site.     

Evaluation of landfill leachate in arid climate-a case study

Generation of leachate from municipal solid waste (MSW) landfill in arid regions has long been neglected on the assumption that minimal leachate could be formed in the absence of precipitation. Therefore, a case study was conducted at two unlined MSW landfills, of different ages, in the state of Kuwait in order to determine the chemical characteristics of leachate and examine the mechanism of leachate formation. Leachate quality data were collected from both active and old (closed) landfills where co-disposal of MSW and other solid and liquid wastes is practiced. The analysis of data confirms that leachates from both landfills are severely contaminated with organics, salts and heavy metals. However, the organic strength of the leachate collected from the old landfill was reduced due to waste decomposition and continuous gas flaring. A significant degree of variability was encountered and factors which may influence leachate quality were identified and discussed. A water balance at the landfill site was assessed and a conceptual model was presented which accounts for leachate generation due to rising water table, capillary water and moisture content of the waste.     

Comparative toxicity of solid waste leachates to Daphnia magna

The comparative acute and chronic toxicities of municipal, industrial, coal-fired power plant, and synthetic fuel solid waste leachates to the aquatic invertebrate Daphnia magna were determined. Seventeen leachates were laboratory-derived by extraction with 0.5 N acetic acid, and one, an arsenic-contaminated groundwater, was naturally derived. The acute toxicity 48-h LC₅₀ estimates (concentrations of the test materials that killed 50% of the test organisms in 48 h) ranged from 0.0005% for a dye waste leachate to > 100% (i.e., undiluted) for a coal gasification waste leachate. The most toxic leachates were derived from a dye waste, a plater's waste, and the arsenic-contaminated groundwater, and the least toxic were from a soybean process cake waste and a coal gasification waste. Of the 16 leachates used in the 28 day chronic toxicity tests, only the arsenic-contaminated groundwater and a municipal sewage sludge significantly affected D. magna reproduction. The former material at 1.0% concentration and the sludge at 0.1% caused about an 88% reduction in the numbers of young produced by exposed females compared with controls. Generally, the industrial waste leachates were more toxic than those from the power plant and synthetic fuel wastes. Because its presence in the test materials interfered with interpretation of the results, acetic acid may not be an appropriate extraction medium for preparation of leachates.     

Organoarsenicals in poultry litter: Detection,fate, and toxicity

Arsenic contamination in groundwater has endangered the health and safety of millions of people around the world. One less studied mechanism for arsenic introduction into the environment is the use of organoarsenicals in animal feed. Four organoarsenicals are commonly employed as feed additives: arsanilic acid, carbarsone, nitarsone, and roxarsone. Organoarsenicals are composed of a phenylarsonic acid molecule with substituted functional groups. This review documents the use of organoarsenicals in the poultry industry, reports analytical methods available for quantifying organic arsenic, discusses the fate and transport of organoarsenicals in environmental systems, and identifies toxicological concerns associated with these chemicals. In reviewing the literature on organoarsenicals, several research needs were highlighted: advanced analytical instrumentation that allows for identification and quantification of organoarsenical degradation products; a greater research emphasis on arsanilic acid, carbarsone, and nitarsone; identification of degradation pathways, products, and kinetics; and testing/development of agricultural wastewater and solid treatment technologies for organoarsenical-laden waste.     

Goal-based waste management strategy to reduce persistence of contaminants in leachate at municipal solid waste landfills

The required minimum 30-year post-closure care period for municipal solid waste (MSW) landfills can be shortened by reducing or eliminating of MSW components with long-terms effect in gas and leachate. The objectives of this study were to evaluate the relative persistence of landfill gas, leachate quantity, and selected leachate parameters using post-closure monitoring data from a case study landfill in south Florida. The relative persistence of selected decomposition byproducts in leachate were evaluated by both zero order and first order models based on monitoring data from the case study landfill. The analyses show that although gas and leachate production rates diminish very quickly, some contaminants remain in leachate as the decomposition process continues at a slower rate. For the case study landfill, the parameters which have been detected consistently at high concentrations (above MCL) included chloride, TDS, iron, bicarbonate, benzene, and vinyl chloride. Among these, vinyl chloride has the fastest and TDS has the slowest rate of disappearance in the landfill environment. The effect of waste diversion on persistence times of the selected persistent leachate quality parameters was evaluated. For example, a 40% reduction in the amount of plastics deposited in the landfill could reduce the monitoring time for benzene from 59 to 39 years. Zero order model underestimates the persistence times of the contaminants in leachate due to its linear nature. Shortening the monitoring times can provide significant savings for municipalities who need to continue monitoring leachate quality until the MCL levels are reached.     

On-site radioactive soil contamination at the Andreeva Bay shore technical base, Northwest Russia

The radioactive waste (RAW) storage site at Andreeva Bay in the Russian Northwest has experienced radioactive contamination both as a result of activities carried out at the site and due to incidents that have occurred there in the past such as accidental releases of radioactive materials. The site is an interesting case study for decommissioning due to the extremely large amounts of radioactivity present at the site and the conditions under which it is stored; very little has been previously published in the scientific literature about this site. This paper complements the paper describing dose rates at Andreeva Bay which is published in this issue of Journal of Environmental Radioactivity by the same authors. This study presents new data related to the activity concentrations of (137)Cs and (90)Sr in surface soils and measurements of alpha- and beta-particle fluxes taken at different areas around the site. Limited data on 60Co is also presented. The results of the study indicate that the main areas of site contamination are associated with the former spent nuclear fuel storage facility at Building 5, due to accidental discharges which began in 1982. Substantial contamination is also observed at the solid radioactive waste storage facilities, probably due to the ingress of water into these facilities. More than 240 samples were measured: maximum contamination levels were 1 x 10(6)Bq/kg (137)Cs (mean value 4.1 x 10(5)Bq/kg) and 4 x 10(6)Bq/kg (90)Sr (mean value 1.2 x1 0(5)Bq/kg). Localised patches of alpha and beta contamination were also observed throughout the site.     

Delineation of groundwater contamination around an ash pond: geochemical and GIS approach

The study has investigated the levels of metal contamination in groundwater due to particulate matter fallout and leaching from ash pond and assigned contamination indices for the adjacent localities around an ash disposal site with application of geographic information systems (GIS). Fe, Ba, Cu, Mn, S, Pb, V, and Zn were found to be the major contaminants in groundwater. Enrichment factors (EF) of these elements with respect to the United States Environmental Protection Agency (USEPA) maximum contaminant levels show high values for Mn, Fe, and Pb in groundwater. The zone of attenuation for Ba, Fe, Cu, Mn, S, and Zn in groundwater is about 600-900 m from the ash pond, while Pb did not show any significant attenuation even at a distance of 1200 m. Tube wells around Rankasingha and Kukurhanga villages are most contaminated whereas open wells of Lachhmanpur, Kaniapada, and Kurudul villages showed higher degrees of contamination.     

The use of carbon and nitrogen isotope ratios to identify landfill leachate contamination: Green Island Landfill, Dunedin, New Zealand

A study was undertaken to determine whether the isotopic ratios of C and N could be used to uniquely identify municipal solid waste landfill leachate as a source of contamination in the Kaikorai Estuary, Dunedin, New Zealand. Leachate samples were taken from the adjacent Green Island Landfill (GILF), and surface water samples were collected over an 8-month period from the stream and estuary, upstream and downstream of the landfill. Samples were analysed for delta(13)C-dissolved inorganic carbon (DIC), delta(15)N-NO(3)(-), delta(15)N-NH(4)(+), and particulate organic matter (POM) delta(13)C and delta(15)N. Plant material collected along the Kaikorai Stream was analysed for POM delta(13)C and delta(15)N. Leachate was found to have a distinct isotopic signature characterised by a highly enriched delta(13)C-DIC (as much as 16.11+/-0.23 per thousand ) and highly enriched delta(15)N-NH(4)(+) (as much as 27.42+/-0.90 per thousand ). Evidence of leachate contamination was found in the isotopic signatures of downstream delta(13)C-DIC, delta(15)N-NH(4)(+), and delta(13)C and delta(15)N of plant material POM. Other potential sources of enriched delta(13)C-DIC and delta(15)N-NH(4)(+) present in the study area, such as estuarine waters and livestock effluent, were eliminated on the basis of their isotopic characteristics.     

Water quality and impacts of pollution sources for Eymir and Mogan Lakes (Turkey)

Mogan and Eymir Lakes are two shallow lakes, interconnected hydrologically in the close vicinity of Ankara, Turkey. A total of 245 km(2) of the total 971.4 km(2) watershed is under environmental protection status as "G?lba?i Specially Protected Area". Potential impacts from extensive agriculture, recreation, incomplete infrastructure and other human activities, such as residential settlements, are discussed with reference to previous and more recent pollution monitoring. Six monitoring stations enabling follow-up of previous work were selected in this study. These were on the creeks feeding the lake systems. Generally, summer months showed heavier pollution loads, with Eymir Lake concentrating the pollutants due to flow from Mogan Lake. When compared with the 1995 study; COD, total-P, Kjeldahl-N in the six stations were close or slightly decreased in the present study. Suspended solids significantly decreased; possibly due to erosion control measures and decreased domestic wastewater. The improvement in the pollution state of the lakes is attributed to the construction of a sewage system going around Mogan Lake and collecting wastewater discharges and restrictions to urban settlement development around the lakes brought by the 1/25,000 land use plan controlling further impact from residential developments within the protected area boundaries. The study, while addressing water quality and interactions due to human activities in shallow lakes, also discusses problems associated with human impacts in protected areas with the aim of presenting a complicated case study.     

Spatial variability of shallow groundwater level, electrical conductivity and nitrate concentration, and risk assessment of nitrate contamination in North China Plain

In recent years, nitrate (NO3) contamination of groundwater has become a growing concern for people in rural areas in North China Plain (NCP) where groundwater is used as drinking water. The objective of this study was to evaluate groundwater resource level, to determine groundwater quality and to assess the risk of NO3 pollution in groundwater in Quzhou County in the NCP. Ordinary Kriging (OK) method was used to analyze the spatial variability of shallow groundwater level, groundwater electrical conductivity (EC) and NO3-N concentrations, and Indictor Kriging (IK) method was used to analyze the data with NO3-N concentrations equal or greater than the groundwater NO3 pollution threshold (20 mg L(-1)). The results indicated that groundwater level averaged 9.81 m, a level 6 m lower than in 1990. The spatial correlation distances for groundwater level, EC and NO3-N concentration were 21.93, 2.19 and 3.55 km, respectively. The contour map showed that shallow groundwater level areas extended from north to south across the County. Groundwater EC was above 3 dS m(-1) in the most part of the northern county. Groundwater NO3 pollution (NO3-N> or =20 mg L(-1)) mainly occurred in the County Seat areas due to wastewater irrigation and excessive fertilizer leaching from agricultural fields. At Henantuang town, besides suburban of the County Seat, groundwater was also contaminated by NO3 shown by the map generated using the IK method, which was not reflected in the map generated using the OK method. The map generated using the OK method could not reflect correctly the groundwater NO3 pollution status. The IK method is useful to assess the risk of NO3 pollution by giving the conditional probability of NO3 concentration exceeding the threshold value. It is suggested that risk assessment of NO3 pollution is useful for better managing groundwater resource, preventing soil salinization and minimizing NO3 pollution in groundwater.     

Contamination of drinking water resources in the Mekong delta floodplains: arsenic and other trace metals pose serious health risks to population

This study presents a transnational groundwater survey of the 62,000 km(2) Mekong delta floodplain (Southern Vietnam and bordering Cambodia) and assesses human health risks associated with elevated concentrations of dissolved toxic elements. The lower Mekong delta generally features saline groundwater. However, where groundwater salinity is <1 g L(-)(1) Total Dissolved Solids (TDS), the rural population started exploiting shallow groundwater as drinking water in replacement of microbially contaminated surface water. In groundwater used as drinking water, arsenic concentrations ranged from 0.1-1340 microg L(-)(1), with 37% of the studied wells exceeding the WHO guidelines of 10 microg L(-)(1) arsenic. In addition, 50% exceeded the manganese WHO guideline of 0.4 mg L(-)(1), with concentrations being particularly high in Vietnam (range 1.0-34 mg L(-)(1)). Other elements of (minor) concern are Ba, Cd, Ni, Se, Pb and U. Our measurements imply that groundwater contamination is of geogenic origin and caused by natural anoxic conditions in the aquifers. Chronic arsenic poisoning is the most serious health risk for the ~2 million people drinking this groundwater without treatment, followed by malfunction in children's development through excessive manganese uptake. Government agencies, water specialists and scientists must get aware of the serious situation. Mitigation measures are urgently needed to protect the unaware people from such health problems.     

Introduction of a recycling system for sustainable municipal solid waste management: a case study on the greater Banjul area of the Gambia

This research proposes for the introduction of a recycling system in the Gambia to enhance sustainable municipal solid waste management. Poor infrastructures, coupled with inadequate resources and lack of funding, work against the optimization of a MSW disposal service. In the authors’ view, authorities in charge of waste management need to change not only behaviors, but modernize their processes. Recycling technology is a key part of the solution. A model has been developed which suggest the involvement of stakeholders to achieve meaningful sustainable MSWM. This can be achieved by recognizing the role of the informal sector through community-based organizations, Non-Governmental Organizations (NGOs), and the private sector. The open dump approach is leading to severe environmental consequences as the groundwater and soil within the dump is been contaminated. In this study, an integrated municipal solid waste management approach was developed with a model to help achieve sustainable municipal solid waste management. Resource recovery, not waste disposal, must be the ultimate goal with clearly defined end user markets so that the recovery loop is complete. Mandatory sorting of waste at household level would help greatly in making recycling activity successful.     

Influence of global change on phytoplankton and nutrient cycling in the Elbe River

The effects of changing climatic and socioeconomic conditions on the water quality of the Elbe River were investigated using the deterministic model QSim. Since the impact of global change on river water quality marks the endpoint of various processes in the catchment and in the atmosphere, this study was performed within a network of interacting models that determined input parameters for water quality simulations. The development of phytoplankton and nutrient concentrations under conditions of global change was modeled along a 700 km stretch of the river. The simulations revealed a strong, scale-dependent effect of climate change on phytoplankton biomass, leading to a longitudinal shift of the dominating processes (primary productivity vs. respiration) along the river continuum. Under reduced flow, combined with increasing temperature and global radiation, phytoplankton biomass increased and phytoplankton maxima shifted in upstream direction, followed by higher system respiration rates in the adjacent downstream sections. In contrast, higher flow shifted the phytoplankton maximum toward the downstream sections. Even a drastic reduction of phosphorus inputs from anthropogenic sources had only limited influence on algal biomass, due to the ability of algal cells to store phosphorus. A strong reduction in P-inputs especially in the headwaters would be necessary to counterbalance the possible climate-induced effects on algal biomass.     

Environmental geochemistry and pollution studies of Aliaga metal industry district

The Aliaga metal industry district located 50 km northwest of Izmir City, in Turkey, includes many metal factories. The geology of the area is represented by Mesozoic flysch deposits and Cenozoic volcano sedimentary rocks. Tectonic elements are NE-SW and NW-SE trending faults and a W-NW trending fault direction that is important for water supply. Rock, soil, stream sediment, and water samples taken at various distances from the industrial area were analyzed for Fe, Ti, Mn, Cr, Pb, Cu, Ni, Zn, and Mo. According to the results, the elements in rocks are reasonable for the range of "Clarke" values, but in the soils and stream sediment, they comprise higher values than are acceptable for agricultural activities. Toxicity analyses were carried out in the drinking artesian water of Cakmakli village and wastewater samples of the factories and river water both of which are used for irrigation of the agricultural areas in and around the investigated area. The people should, however be made aware that this waste and river water is unacceptable for agriculture. Additionally, the contamination of seawater in Nemrut Bay is probably caused by contaminated river and underground water running to the sea. The chemical and toxicity analysis of drinking water samples show that they are above accepted standards and harmful. Previous air pollution studies (funnel gas emission analyses) also show that gas emission contains high amount of dust particles with high Fe, Zn, Pb, and Cu concentrations. As a result, all elements analyzed are of great importance relative to problems concerning contamination of the soil, stream sediment, ground surface water, and air by individual metals from uncontrolled processing of some metal factories.     

Assessment of groundwater contamination in a suburban area of Chennai,Tamil Nadu,India

Groundwater source is the major source of drinking water in most of the suburban areas of India. Groundwater quality was analyzed for pH, TDS, hardness, chloride, fluoride, nitrate, ammonia, phosphate, total coliform and E. coli for the period of January–December 2013. Samples were collected from 10 locations that include 10 shallow wells and 10 deep wells in each location. The quality variation between both shallow and deep wells during pre- and post-monsoon was analyzed. The improper disposal of solid waste and the distance of septic tank were pronounced on E. coli count. The analysis reveals that groundwater contamination is influenced by seasonal changes, environmental condition of the well and maintenance of the well. The high contamination was observed in the wells which are near to the Pallikaranai marsh, and during post-monsoon season, the total dissolved solids and nitrite parameters are slightly increased, whereas chloride increases during pre-monsoon season. Correlation analysis reveals that the chloride and nitrite have a significant relation. The results suggested that the groundwater immediately needs broader protection.     

An evaluation of mixed species in-situ and ex-situ feeding assays: the altered response of Asellus aquaticus and Gammarus pulex

Mixed species feeding assays were undertaken with pollution sensitive (Gammarus pulex) and tolerant (Asellus aquaticus) macro-invertebrates during August 2003 and April 2004. The purpose of this study was to establish if a test animals' response is comparable during in-situ and ex-situ toxicity tests. Seven test sites were established along an undisclosed stream, which received leachate discharge from an unlined, disused UK landfill site. Sampling points A-B were upstream of the contamination, C was adjacent to the influx and D-G were downstream of the leachate discharge (at 100 m intervals). During the in-situ and ex-situ tests, 2-week-old male laboratory bred A. aquaticus and G. pulex were used as test animals. The animals were transplanted to the seven sampling points for the duration of the in-situ tests, whilst water samples from each site were returned to the laboratory for ex-situ testing. The results show that the animals' mortality and feeding rates followed similar trends during the in-situ and ex-situ tests, however, the animals' response was amplified during the in-situ tests. It was also observed that the effects were greater in April, compared to August that may be attributed to a higher frequency of rainfall during spring, which could have flushed a greater proportion of the contaminant load from the waste mass and as a consequence, higher levels of pollution may have leached into the stream from the landfill site. The study, therefore, concludes that in-situ toxicity tests are a more precise monitoring technique, in comparison to ex-situ assays.     

中国固体废物管理政策变迁逻辑与完善路径

系统梳理固体废物管理政策的变迁逻辑,研究固体废物管理政策的聚焦内容和发展趋向,有助于明晰固体废物管理政策完善路径。研究立足于已颁布的固体废物管理政策,运用统计方法分析固体废物管理政策的文本结构和内容,找出中国固体废物管理政策变迁的内在逻辑;紧密结合当前“无废城市”建设的政策需求,提出政策优化完善路径。研究发现:固体废物管理政策文本类型多元、效力级别多样,政策框架体系逐步优化完善;固体废物管理政策热点具有鲜明的时代发展烙印和动态演变特征,政策涉及的领域越来越广,政策内容更具针对性和全面性,政策执行更具指向性和可操作性;无害化、减量化、资源化,污染防治、监督管理、二次污染、回收利用、循环经济等是政策关注焦点;政府从宏观层面强化顶层设计,以政策引导规范为主,注重政策协同、技术支撑、治理水平提升等助推无害化、减量化、资源化目标实现;固体废物管理政策实施的工具手段多元化、要素支撑多样化,固体废物管理的技术支撑关注度逐步提升、管理模式与治理路径已进入适应性转型。立足现实需要,固体废物管理的市场化政策与激励机制不足,适用性技术关注度不高,综合管理水平和治理能力亟待提升。结合国外“无废城市”建设的理论研究、实践行动和政策举措,从固体废物生命周期管理政策、技术范式政策、主体协同政策、引导激励政策及法律法规政策等方面提出中国“无废城市”建设的政策完善路径方向。     

City surface solid waste in Nigerian cities

Within the last few years, uncleared solid wastes, in the form of heaps, have become a common sight in many Nigerian streets and open spaces. In order to assess the magnitudes of these wastes, a survey of selected 15 Nigerian cities was conducted for 2 months in 1982 with a team of 116 enumerators. It was found that the volumes of these uncleared wastes ranged from about 2 × 10⁶ kg/yr to as high as 56 × 10⁶ kg/yr in the cities studies. It was also found that the areas within a radius of 0.5 km of the city centres accounted for about 40% of these uncleared volumes of solid wastes.As distances increased from the city centres, the volumes of these wastes tended to decline. Therefore, it was determined that the main problem areas for uncleared solid wastes are in and around the city centres. These areas should demand special attention by city waste disposal agents.     

Exposure and vulnerability to climate extremes: population and asset exposure to coastal flooding in Dar es Salaam, Tanzania

The paper provides a first quantitative estimate of the potential number of people and value of assets exposed to coastal flooding in Dar es Salaam, Tanzania. The study used an elevation-based geographic information system-analysis based on physical exposure and socio-economic vulnerability under a range of climate and socio-economic scenarios. It particularly considered a worst-case scenario assuming even if defences (natural and/or man-made) exist, they are subjected to failure under a 100-year flood event. About 8% of Dar es Salaam lies within the low-elevation coastal zone (below the 10 m contour lines). Over 210,000 people could be exposed to a 100-year coastal flood event by 2070, up from 30,000 people in 2005. The asset that could be damaged due to such event is also estimated to rise from US35 million (2005) to US35 million (2005) to US10 billion (2070). Results show that socio-economic changes in terms of rapid population growth, urbanisation, economic growth, and their spatial distribution play a significant role over climate change in the overall increase in exposure. However, the study illustrates that steering development away from low-lying areas that are not (or less) threatened by sea-level rise and extreme climates could be an effective strategic response to reduce the future growth in exposure. Enforcement of such policy where informal settlements dominate urbanisation (as in many developing countries) could undoubtedly be a major issue. It should be recognised that this analysis only provides indicative results. Lack of sufficient and good quality observational local climate data (e.g. long-term sea-level measurements), finer-resolution spatial population and asset distribution and local elevation data, and detailed information about existing coastal defences and current protection levels are identified as limitations of the study. As such, it should be seen as a first step towards analysing these issues and needs to be followed by more detailed, city-based analyses.