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151.
Patil MP Subramani T Patil SA Chakrabarti T 《Environmental monitoring and assessment》2002,76(3):299-309
A comprehensive environmental assessment (EA) is a pre-requisite before the site for developing a hazardous waste treatment and disposal facility (HWTDF) is selected. However, the resource limitations, especially for developing countries, often dictatethat the detailed EA be restricted to those sites, which are constraint free and have low hazard potentials. Thus, a preliminary screening exercise for assessing the suitability ofsite for developing the HWTDF needs to be carried out to avoid huge costs involved in detailed EA. While screening a HWTDF site,various factors such as present land use, ecologically sensitiveareas, geology and hydrogeology of the area, the quality and quantity of wastes, engineered safeguards, and the operationalprocedures that need to be adopted, are required to be addressed. In this paper, a multi-level screening criteria employing RemoteSensing, Constraint Mapping, Groundwater Pollution Potential Index (DRASTIC Index), and the Site Ranking was used to assess the suitability of a proposed site for the development of HWTDF.The study helped to identify various constraints at the proposedsite and their significance on the development of the HWTDF. 相似文献
152.
Market samples (60) of six seasonal vegetables were monitoredduring 1996–1997 to determine the magnitude of pesticidalcontamination. The estimation of insecticide residuesrepresenting four major chemical groups i.e. organochlorine,organophosphorous, synthetic pyrethroid and carbamate, was doneby adopting a multiresidue analytical technique employingGC-ECD and GC-NPD systems with capillary columns. The testedsamples showed 100% contamination with low but measurableamounts of residues. Among the four chemical groups, theorganophosphates were dominant followed by organochlorines,synthetic pyrethroids and carbamates. About 23% of the samplesshowed contamination with organophosphorous compounds abovetheir respective MRL values. More extensive studies coveringdifferent regions of Haryana state are suggested to get a clearidea of the magnitude of vegetable contamination with pesticideresidues. 相似文献
153.
This paper discusses the REAP1 model and its application for the analysis of CO2 reduction and waste management policies for Japanese petrochemicals. The pros and cons of this modelling approach in comparison to other tools is elaborated. This is followed by a discussion of the model code and the modelling results. The results show that CO2 policies can have significant impacts on waste flows and waste policies can have significant CO2 benefits. As a consequence both effects must be considered in policy assessment. Pricing instruments are recommended instead of regulations because of the complex physical relations in the materials life cycle that extend beyond sector boundaries. A taxation approach is superior to a subsidy approach because rebound effects can be avoided. 相似文献
154.
Zimmer AT 《Journal of environmental monitoring : JEM》2002,4(5):628-632
Recent research has indicated that insoluble ultrafine aerosols (ie., particles whose physical diameters are less than 100 nm) may cause adverse health effects due to their small size, and that toxicological response may be more appropriately represented by particle number or particle surface area. Unfortunately, current exposure criteria and the associated air-sampling techniques are primarily mass-based. Welding processes are high-temperature operations that generate substantial number concentrations of ultrafine aerosols. Welding aerosols are formed primarily through the nucleation of metal vapors followed by competing growth mechanisms such as coagulation and condensation. Experimental results and mathematical tools are presented to illustrate how welding metallurgy influences the chemical aspects and dynamic processes that initiate and evolve the resultant aerosol. This research suggests that a fundamental understanding of metallurgy and aerosol physics can be exploited to suppress the formation of undesirable chemical species as well as the amount of aerosol generated during a welding process. 相似文献
155.
A. M. Cicero M. Mecozzi R. Morlino D. Pellegrini E. Veschetti 《Environmental monitoring and assessment》2001,71(3):297-316
Dredging is a very important procedure for harbor management. InItaly the guidelines for the offshore dumping of dredged materials are issued by the Ministry of Environment. Theydescribed a few steps of dredging activities, such as thesampling strategy, but do not deal with limits or guide-valuesfor the chemical, physical and biological composition of theresulting sediments. The quality of dredged materials is mainlydependent on the presence of inorganic and organic pollutants.In particular, polychlorinated biphenyls (PCBs) and organo-chlorinated pesticides are seen as a high priority inmarine environment by international organizations because oftheir persistence, toxicity and bioaccumulation capacity.In this article the presence of some PCBs and organo-chlorinatedpesticides in sediment samples collected from the harbor ofLivorno (Northern Tyrrhenian Sea) was investigated. Theconcentration of HCHs, Aldrin, Chlordanes, DDEs, DDTs, and PCBsin 12 representative sites ranged between <1 g kg–1and 95, 19, 32, 35, 107, and 111 g kg–1, respectively.The application of univariate and multivariate statisticaltechniques, such as linear regression analysis and principalcomponent analysis, to the experimental data showed a differentdistribution of PCBs in the two sediment layers. On thecontrary, the vertical distribution of the other investigatedpollutants was more homogeneous and affected by randomvariability. The multivariate approach was an important tool to establish more rational criteria for the management of dredged materials. 相似文献
156.
The article describes the use of Scots pine bark to identifynitrogen sources in eastern Germany, as well as background areas in Russia and Bulgaria, by using natural isotope ratios of total nitrogen (Nt) and individual N compoundssuch as ammonium (NH4
+), nitrate (NO3
-)and amid nitrogen (amide-N). The samples collected were analysed using an elemental analyser in connection with a gas isotope mass spectrometer (EA-IRMS). Natural 15N abundances in pine bark from impact areas suggest that the ammonium accumulated on the surface of the bark is releasedfrom livestock management. Bark of Scots pines growing near agricultural land had highly depleted 15Nt values (between –8 and –12), while bark from background areas (unpolluted areas) displayed slightly negative 15Nt values (mean 15Nt = –3.8). It is assumed that part of the N adsorbed on the bark surface is mainly derived from ammonia(mean 15Nt = –40.3) escaping from livestock housing and during the application of manure. This assumption is confirmed by experiments under controlled conditions in which manure samples were spread on soil. In addition, temporal and spatial variations of 15Nt abundances in pine bark from various locations in eastern Germany as wellas pine stands in Nature Park Dübener Heath are discussed. 相似文献
157.
Fagundez LA Fernández VL Marino TH Martín I Persano DA Rivarola Y Benítez M Sadañiowski IV Codnia J Zalts A 《Environmental monitoring and assessment》2001,71(1):61-70
Passive diffusion samplers were employed in San Miguel(Buenos Aires Metropolitan Area) for a preliminary airpollution monitoring. The highest loads were observedin downtown, compared with an urban background site.Total suspended particulate matter (TSPM) varied from0.257 to 0.033 mg cm-2 month-1; dust was examinedfor particle nature and size distribution. A similartrend was observed for nitrogen dioxide (NO2) andTSPM spatial distribution, suggesting that traffic isthe major pollution source. Sulphur dioxide (SO2)values were low and rather homogeneous. Levels for theinvestigated pollutants are below EPA's guide linevalues. Geographic (flat area, near to Rio de LaPlata) and climatologic factors (rainfalls andvariable wind directions) contribute to disperse pollutants. 相似文献
158.
A statistical quality control approachto detect changes in groundwater quality from aregulated waste unit is described. The approachapplies the combined Shewhart-CUSUM control chartmethodology for intrawell comparison of analyteconcentrations over time and does not require anupgradient well. A case study from the U.S.Department of Energy's Hanford Site is used forillustration purposes. This method is broadlyapplicable in groundwater monitoring programs wherethere is no clearly defined upgradient location, thegroundwater flow rate is exceptionally slow, or wherea high degree of spatial variability exists inparameter concentrations. This study also indicatesthat the use of the Data Quality Objectives (DQO)process can assist in designing an efficient andcost-effective groundwater monitoring plan to achievethe optimum goal of both low false positive and lowfalse negative rates (high power). 相似文献
159.
Thomas W. May Michael J. Walther Jimmie D. Petty James F. Fairchild Jeff Lucero Mike Delvaux Jill Manring Mike Armbruster David Hartman 《Environmental monitoring and assessment》2001,72(2):179-206
The Republican River Basin of Colorado,Nebraska, and Kansas lies in a valley which contains PierreShale as part of its geological substrata. Selenium is anindigenous constituent in the shale and is readily leached intosurrounding groundwater. The Basin is heavily irrigated throughthe pumping of groundwater, some of which is selenium-contaminated, onto fields in agricultural production. Water,sediment, benthic invertebrates, and/or fish were collected from46 sites in the Basin and were analyzed for selenium to determinethe potential for food-chain bioaccumulation, dietary toxicity,and reproductive effects of selenium in biota. Resultingselenium concentrations were compared to published guidelines orbiological effects thresholds. Water from 38% of the sites (n = 18) contained selenium concentrations exceeding 5 g L-1, which is reported to be a high hazard for selenium accumulation into the planktonic food chain. An additional 12 sites (26% of the sites) contained selenium in water between 3–5 g L-1, constituting a moderate hazard. Selenium concentrations in sedimentindicated little to no hazard for selenium accumulation fromsediments into the benthic food chain. Ninety-five percent ofbenthic invertebrates collected exhibited selenium concentrationsexceeding 3 g g-1, a level reported as potentially lethal to fish and birds that consume them. Seventy-five percent of fish collected in 1997, 90% in 1998, and 64% in 1999 exceeded 4 g g-1selenium, indicating a high potential for toxicity andreproductive effects. However, examination of weight profilesof various species of collected individual fish suggestedsuccessful recruitment in spite of selenium concentrations thatexceeded published biological effects thresholds for health andreproductive success. This finding suggested that universalapplication of published guidelines for selenium may beinappropriate or at least may need refinement for systems similarto the Republican River Basin. Additional research is needed todetermine the true impact of selenium on fish and wildliferesources in the Basin. 相似文献
160.
Ambient Air Quality Monitoring Network Design for Assessing Human Health Impacts from Exposures to Airborne Contaminants 总被引:1,自引:0,他引:1
Existing methods of establishing ambientair quality monitoring networks typically evaluateonly parameters related to ambient concentrations ofthe contaminant(s) of interest such as emissionsource characteristics, atmospheric transport anddispersion, secondary reactions, depositioncharacteristics, and local topography. However,adverse health risks from exposures to airbornecontaminants are a function of the contaminant andthe anatomic and physiologic characteristics of theexposed population. Thus, ambient air qualitymonitoring networks designed for the protection ofpublic health or for epidemiological studiesevaluating adverse health impacts from exposures toambient air contaminants should account for bothcontaminant characteristics and human healthparameters. A methodology has been establishedwhich optimizes ambient air quality monitoringnetworks for assessments of adverse human healthimpacts from exposures to airborne contaminants byincorporating human health risk assessmenttechniques. The use of risk assessment techniquesas the basis for designing ambient air qualitymonitoring networks will help to target limitedfinancial and human resources to evaluate humanhealth risks from exposures to airbornecontaminants. 相似文献