The Middle Route of the South-to-North Water Diversion Project (MRP) is strategically important for China, and has made a great contribution to the sustainable development of society and economy in ...North China. Various potential risks of sudden water pollution accidents are distributed along the long canal, which may result in huge losses and endanger the safety of water supply. In order to provide technical support for emergent operations in the MRP, the emergency operation technologies for sudden water pollution accidents were developed. This book introduces these emergency operation technologies, including simulation technology for hydrodynamic and water quality in the main canal, traceability technology, emergency operations, and an emergency management system for sudden water pollution accidents.This book is supported by the Major Science and Technology Program for Water Pollution Control and Treatment (2017ZX07108-001) and National Key R&D Program of China (2017YFC0406004).
Following rapid population increase and industrial development, the ever increasing environmental pollution and the associated sanitation-related problem are no longer regional or local but have ...become an issue requiring global-dimensional concern and the provision of problem-solving alternatives. Especially, since most problems result from inappropriate sewerage and the lack of sewage treatment system are in a serious state occurring in economically underdeveloped regions, and as such, their significance is enormous. The United Nations Environment Programme (UNEP) has been making efforts to establish the technology selection methodology applicable in developing countries, through the accurate status, investigation and analysis of the wastewater management state in Asian and African regions, and the sanitation management guideline utilisable by political leaders or decision-makers. As part of this effort, the Korea Institute of Water Environment (KIWE), together with the UNEP, selected China and Vietnam (in Asia) and Kenya and Ethiopia (in Africa) as subject countries to investigate and perform on-site sanitation management investigations and analysis in this research. Results obtained from the on-site investigation were analysed, and in order to be helpful in establishing a strategy for sanitation management in underdeveloped countries, the strategic framework (SF) has been made based on characterised results.
Circulation of
Cryptosporidum and
Giardia in the environment can be facilitated by spreading of sewage sludge on agricultural or livestock grazing lands or depositing in landfills. Solid waste ...landfill leachate and sewage sludge samples were quantitatively tested for
C. parvum and
C. hominis oocysts, and
G. lamblia cysts by the combined multiplexed fluorescence in situ hybridization (FISH) and immunofluorescent antibody (IFA) method. Subsequently, the effects of four sanitization treatments (i.e., ultrasound and microwave energy disintegrations, and quicklime and top-soil stabilization) on inactivation of these pathogens were determined. The landfill leachate samples were positive for
Giardia, and sewage sludge samples for both
Cryptosporididium and
Giardia. The overall concentration of
G. lamblia cysts (mean; 24.2/g) was significantly higher (
P<0.01) than the concentration of
C. parvum and
C. hominis oocysts (mean; 14.0/g). Sonication reduced the load of
G. lamblia cysts to non-detectable levels in 12 of 21 samples (57.1%), and in 5 of 6 samples (83.3%) for
C. parvum and
C. hominis. Quicklime stabilization treatment was 100% effective in inactivation of
Cryptosporidium and
Giardia, and microwave energy disintegration lacked the efficacy. Top-soil stabilization treatment reduced gradually the load of both pathogens which was consistent with the serial dilution of sewage sludge with the soil substrate. This study demonstrated that sewage sludge and landfill leachate contained high numbers of potentially viable, human-virulent species of
Cryptosporidium and
Giardia, and that sonication and quicklime stabilization were the most effective treatments for sanitization of sewage sludge and solid waste landfill leachates.
This article provides a review and synthesis of the published and selected unpublished literature on historical asbestos exposures among skilled craftsmen in various nonshipyard and shipyard ...settings. The specific crafts evaluated were insulators, pipefitters, boilermakers, masons, welders, sheet-metal workers, millwrights, electricians, carpenters, painters, laborers, maintenance workers, and abatement workers. Over 50 documents were identified and summarized. Sufficient information was available to quantitatively characterize historical asbestos exposures for the most highly exposed workers (insulators), even though data were lacking for some job tasks or time periods. Average airborne fiber concentrations collected for the duration of the task and/or the entire work shift were found to range from about 2 to 10 fibers per cubic centimeter (cm
3
or cc) during activities performed by insulators in various nonshipyard settings from the late 1960s and early 1970s. Higher exposure levels were observed for this craft during the 1940s to 1950s, when dust counts were converted from millions of particles per cubic foot (mppcf) to units of fibers per cubic centimeter (fibers/cc) using a 1:6 conversion factor. Similar tasks performed in U.S. shipyards yielded average fiber concentrations about two-fold greater, likely due to inadequate ventilation and confined work environments; however, excessively high exposure levels were reported in some British Naval shipyards due to the spraying of asbestos. Improved industrial hygiene practices initiated in the early to mid-1970s were found to reduce average fiber concentrations for insulator tasks approximately two- to five-fold. For most other crafts, average fiber concentrations were found to typically range from <0.01 to 1 fibers/cc (depending on the task or time period), with higher concentrations observed during the use of powered tools, the mixing or sanding of drywall cement, and the cleanup of asbestos insulation or lagging materials. The available evidence suggests that although many historical measurements exceeded the current OSHA 8-h time-weighted average (TWA) permissible exposure limit (PEL) of 0.1 fibers/cc, average fiber concentrations generally did not exceed historical occupational exposure limits in place at the time, except perhaps during ripout activities or the spraying of asbestos in enclosed spaces or onboard ships. Additionally, reported fiber concentrations may not have represented daily or actual human exposures to asbestos, since few samples were collected beyond specific short-term tasks and workers sometimes wore respiratory protective equipment. The available data were not sufficient to determine whether the airborne fiber concentrations represented serpentine or amphibole asbestos fibers, which would have a pronounced impact on the potential health hazards posed by the asbestos. Despite a number of limitations associated with the available air sampling data, the information should provide guidance for reconstructing asbestos exposures for different crafts in specific occupational settings where asbestos was present during the 1940 to 2006 time period.
Stagnation is widely believed to predispose water systems to colonization by Legionella. A model plumbing system was constructed to determine the effect of flow regimes on the presence of Legionella ...within microbial biofilms. The plumbing model contained three parallel pipes where turbulent, laminar and stagnant flow regimes were established. Four sets of experiments were carried out with Reynolds number from 10 000 to 40 000 and from 355 to 2000 in turbulent and laminar pipes, respectively. Legionella counts recovered from biofilm and planktonic water samples of the three sampling pipes were compared with to determine the effect of flow regime on the presence of Legionella. Significantly higher colony counts of Legionella were recovered from the biofilm of the pipe with turbulent flow compared with the pipe with laminar flow. The lowest counts were in the pipe with stagnant flow. We were unable to demonstrate that stagnant conditions promoted Legionella colonization. Plumbing modifications to remove areas of stagnation including deadlegs are widely recommended, but these modifications are tedious and expensive to perform. Controlled studies in large buildings are needed to validate this unproved hypothesis.
In the aftermath of Hurricane Katrina, which devastated the city of New Orleans in August 2005, restoration workers were at risk for respiratory illness from exposure to airborne particles and ...microbial agents. In support of an epidemiologic investigation of this risk, an exposure assessment for restoration work activities (demolition, trash & debris management, landscape restoration, sewer/waterline repair, and mold remediation) was performed from 2005 to 2012. For 2005 and 2006, Occupational Safety and Health Administration (OSHA) data (n = 730) for personal and area monitoring of total and respirable dust exposures of restoration workers were accessed and analyzed. The most significant exposures were for demolition work, with average respirable dust exposures in 2005 above the action level of 2.5 mg/m
3
and 17.6% of exposures exceeding the permissible exposure limit (PEL) (5 mg/m
3
). Additional personal and area monitoring for thoracic particulate matter was performed from 2007 to 2012 (n = 774) and samples were assayed for endotoxin and (1→3, 1→6)-β-D-glucan (n = 202). In order to integrate the OSHA data with the later monitoring data, three independent predictive models were developed to convert total and respirable dust measures into the equivalent thoracic dust. The three models were not statistically different and the modeling results were in good agreement with an overall coefficient of variation of 16% for the thoracic dust means across work activities estimated by each of the three models. Overall, thoracic dust exposure levels decreased by about an order of magnitude within the first year after Katrina and then more gradually declined and stabilized through 2012. Estimated average exposures to endotoxin and microbial glucan in 2005 were as high as 256 EU/m
3
and 118 μg/m
3
, respectively, and likewise were seen to decrease dramatically and stabilize after 2005. The results of this exposure assessment support previously published reports of respiratory illness including sinusitis, toxic pneumonitis, and Katrina Cough among restoration workers in the years immediately after the hurricane.
Little is known about how the growth of halogenated disinfection by-products (DBPs) in drinking water is affected by time spent in a distribution system. Experiments were performed to compare the ...rate of trihalomethane and haloacetic acid production in a simulated pipe environment to that observed for the same water held in glass bottles. Results showed that although the rate of chlorine consumption in the pipe was much greater than in the bottle, there was no decrease in the amount of haloacetic acids produced and that trihalomethane levels actually increased by an average of 15%. Separate tests confirmed that this increase was due to a reservoir of organic precursor material associated with deposits on the pipe wall. This work suggests that the rate of DBP production in a distribution system will not necessarily be reduced by increased chlorine consumption due to non-DBP producing reactions with deposits on the pipe wall.
Le dernier rapport du Programme commun OMS/UNICEF de suivi de l'approvisionnement en eau et de l'assainissement (JMP), intitul "Progr s en mati re d'assainissement et d'alimentation en eau - rapport ...2010" pr sente les estimations les plus r centes sur l'alimentation en eau et l'assainissement ainsi que les incidences et les tendances vis- -vis de l'atteinte de la cible des OMD en mati re d'eau potable et d'assainissement. A seulement cinq ans de la date butoir pour les OMD, il appara t essentiel d'intensifier les efforts afin d'atteindre la cible des OMD, en particulier pour l'assainissement, et d'adresser les probl mes de disparit s flagrantes qui existent au niveau mondial.
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