Depending on the requirement for the final effluent in terms of pathogen reduction, only anaerobic and facultative ponds are necessary in some instances. Unless they are property maintained, lagoons can provide a breeding area for mosquitoes and other insects. <> endstream endobj Lagoons - Purdue University College of Engineering PDF United States Environmental Protection Agency Wastewater Technology The pond body directly below the surface aerator of the aeration pond must be reinforced with concrete . They use less energy than most waste water treatment methods. <> Waste Stabilization Ponds (WSPs) are commonly used for sewage treatment. facultative pond advantages and disadvantages facultative pond advantages and disadvantages. >}zUv6yS?iQpH3mB.Ib W?C?H' B`6ke@0wUSy=7I ^>z0WZ6n)/j&}. <>stream the article or any translations thereof. Basins with surface areas many times larger than conventional biological reactors, that utilize relatively low . 0000001707 00000 n The last ponds serves for the retention of stabilised solids and the inactivation of pathogenic microorganisms via heating rise of pH and solar disinfection. endstream <> Its particular focus is on how DFID assistance can best meet the needs of the urban and rural poor for water supply and sanitation services. In addition, it is one of the few low-cost natural processes, which provides good treatment of pathogens. However, large surface areas and expert design are required. to, Advantages and disadvantages of stabilization pond treatment process, Fluid, Electrolyte, and Acid-base Balance, Longmen Town, Lintao County, Gansu Province, launched a large-scale investigation and major renovation of the starch processing industry, The Market Supervision Office of Longmen Town, Lintao County, Gansu Province, carried out a special inspection of food safety before the "Double Festival", Benxi biological hepatitis B and AIDS test box have been registered. PDF Lesson 1 Math Oxidation pond for municipal wastewater treatment | SpringerLink `# ~a8ivHjy2_diw"sfGDl2lG] 9 0 obj Because facultative ponds employ algae as decomposers, the treatment time can range between 2 and 3 weeks, which is attributed to the photosynthetic processes that occur within the unit. facultative pond advantages and disadvantages. facultative pond advantages and disadvantages endobj The impression of spring plowing behind the hard-to-sell fertilizer. <> This makes them particularly suitable for developing countries where many conventional wastewater treatment plants have failed because water and sewer utilities did not generate sufficient revenue to pay the electricity bill for the plant (IRC 2004) (see also -financing projects). The service requires full cookie support in order to view this website. (PDF) Waste Stabilization Ponds: A Viable Alternative for Small The main function of anaerobic ponds is BOD removal, which can be reduced 40 to 85 % (WSP 2007). The report suggests that emerging trends in low-cost, decentralised naturally-based infrastructure and urban wastewater management which promote the recovery and reuse of wastewater resources are increasingly relevant. Provides information on the limitations, advantages and disadvantages, applicability, performance, design criteria, operation and maintenance, and costs of such lagoons. <> Ponds have many advantages and disadvantages compared to treatment in plants. facultative pond advantages and disadvantagesjewelry district nycjewelry district nyc 9 0 obj 90% BOD and TSS; high pathogen reduction and relatively high removal of ammonia and phosphorus; Total HRT: 20 to 60 days, Low capital costs where land prices are low; very low operation costs. <> In the case of high salt content, the use of the water for irrigation is not recommended. facultative pond advantages and disadvantages. 1. endobj Figure 1: Stabilisation pond configurations: AN = anaerobic pond; F = facultative pond; M = maturation pond 2. 17 The documented systems, which vary significantly in terms of complexity, performance and costs, range from simple systems for single-house applications (e.g. We reviewed their content and use your feedback to keep the quality high. 7 0 obj Anaerobic, facultative and maturation ponds as wells as aerated lagoon systems are presented as an appropriate solution in developing countries where sewerage systems are present. x[:4iMH8y'8`"mPIB?/=}~#2,X0@1M?#_73?|qwfTf?i$"1l}8 p\@TeK,O#yFd(rg?dbi'p?,>,Pz|= ? Im~:{;L(5?T2Vs/IZ1sdm4i0LZ$&&Pl-F@:)}0$/R}~jZNg&[ag8Wz ~o X Ecological sanitation constitutes a diversity of options for both rich and poor countries, from household level up to wastewater systems for mega-cities and needs to become recognised by decision-makers at all levels. Required fields are marked *. High self-help compatibility concerning maintenance. facultative pond advantages and disadvantages T w"F:ddH^0% /@ 0[#a%KI E@' _{a~d Q/d"8+ .U p9 GG^tS~0-o_Oa/Vxi>5IJvo}=~4iKuz};p/^x],;^{?-{m*:Vt7u@@7*@ y;tv DG3H.>k+>'//_^V^vzK_^|.^a{uw]+uOZ{uu_Q`dIvP$#&fGF#R0=_ppV f=]%&z\/_uvz/.}=ko_an_]I&^z}-o]_s! (aerobic, anaerobic, and facultative bacteria; fungi; algae; and protozoa) attached to the medium as a biological film or slime layer (approximately 0.1 to 0.2 mm thick). Waste Stabilization Ponds and Constructed Wetlands Design Manual. Design manual for designers, builders and operators on the design and operation of artificially constructed wetlands and waste stabilization ponds. Only slightly polluted wastewater may be discharged directly into primary facultative ponds. facultative pond advantages and disadvantages - Gunsdown.net the wastewater-fed fishponds in Calcutta in India. 5 0 obj FPs can result in the removal of 80 to 95% of the BOD5 (SPERLING 2007), which means an overall removal of 95% over the two ponds (AP and FP). Volume II. Biological Wastewater Treatment in Warm Climate Regions gives a state-of-the-art presentation of the science and technology of biological wastewater treatment, particularly domestic sewage. They are not appropriate for very dense or urban areas. 10 0 obj Communication Accommodation Theory Critical Essay. 8 0 obj This work presents the establishment of an international research collaboration network and main technical recommendations based on an exhaustive assessment on the state-of-the-art of stabilization ponds in the West-African context. Waste Stabilisation Ponds is the third volume in the series Biological Wastewater Treatment. Advantages and disadvantages of stabilization pond treatment - ECHEMI <> 1. Facultative and anaerobic ponds may be charged with high-strength wastewater. Your email address will not be published. Waste Stabilization Ponds (WSP) | SSWM - Find tools for sustainable 9w.OW x2 eM';j OB"#A}zC 3tkIt@v~o? 1 0 obj The second part of the guide consists of technical factsheets which give a practical overview of the technical and economic characteristics, the operating principle and the pros and cons of the 29 sanitation technology options most commonly used in sub-Saharan Africa. The ponds can be used individually, or linked in a series for improved treatment. For the most effective treatment, WSPs should . Besides the poor economic situation and little political support, it is also the lack of training and research that contributes to this situation. 6 0 obj During anaerobic digestion, biogas is produced which could be collected by covering the anaerobic pond with a floating plastic membrane (PENA VARON 2004;WAFLER 2008). endobj [(K The annexe contains a practical collection of factsheets on selected sanitation system options. )L If used in combination with algae and/or fish harvesting, this type of pond is also effective at removing the majority of nitrogen and phosphorus from the effluent (TILLEY et al. Waste Stabilization Pond Systems are summarized and Advanced Integrated Wastewater Pond Systems (AIWPS) are investigated. For the most effective treatment, WSPs should be linked in a series of three or more with effluent being transferred from the anaerobic pond to the facultative pond and, finally, to the aerobic pond. <> The Clinton Water District provides a secondary level of wastewater treatment by using a facultative lagoon system. %PDF-1.6 % Aquatic plants that are present in the pond should also be removed as they may provide a breeding habitat for mosquitoes and prevent light from penetrating the water column. stream Facultative ponds mean large, but shallow basins meant for the treatment of the sewage through the application of both anaerobic and aerobic processes (Bougrier et al. Construction can take place by semi- or unskilled labourers. <> %PDF-1.6 % <> sergei fedorov current wife; melbourne demons 2017; gonzaga assistant coach salary; tribal loans florida. The purpose of this guide is to assist local contracting authorities and their partners in identifying those sanitation technologies best suited to the different contexts that exist within their town. 1 0 obj The ponds can be used individually, or linked in a series for improved treatment. Facultative Treatment Ponds are the simplest of all WSPs and consist of an aerobic zone close to the surface and a deeper, anaerobic zone. ). BOD removal in both types of facultative pond is in the range 60-80%. For multi-level stabilization ponds, separate gates should be set up at each entrance and exit of the stabilization ponds at all levels . "!qAl0s +)\* `sDx>ZHJ,LE.wJgPbLj6dPfn? 0000006544 00000 n Advantages and Disadvantages of Ponds. Part A provides a comprehensive summary concerning the various aspects of constructing, operating and maintaining pond systems. a) Anaerobic Pond, FACTST FACTATI ODS Operation and Maintenance NBS Technical Details 18 0 obj They are designed for BOD removal and can treat water in the BOD range of 100 to 400 kg/ha/day corresponding to 10 to 40 g/m2/day at temperatures above 20C (MARA and PEARSON, 1998). However, bad odour cannot be avoided reliably with high loading rates. If reuse is not possible, WSPs may not be adequate for areas sensitive to eutrophication (UNEP 2004). %PDF-1.4 <> ICP16009155-1 | Copyright@Qingdao ECHEMI Technology Co., Ltd. Search more information of high quality chemicals, good prices and reliable suppliers, visit, This article is an English version of an article which is originally in the Chinese language on echemi.com and is provided for information purposes only. The purified sewage is introduced into the artificial lake and used as a water source for landscape and sightseeing . Detailed design, operation and maintenance guidance is given. PDF Wastewater Stabilization Ponds (WSP) for Wastewater Treatment - EOLSS 51 21 Short factsheet on the design, operation, maintenance and costs of facultative ponds in the United States. Some advantages and disadvantages of facultative lagoons are listed below: Advantages Moderately effective in removing settleable solids, BOD, pathogens, fecal coliform, and ammonia. PES Dispersion BSP-450 99% White liquid Best Make, C9 aromatic hydrocarbon resins 64742-16-1, acrylonitrile/butadiene copolymer 99.6% White CAS9003-18-3 crm, Trade Alert - Delivering the latest product trends and industry news straight to your inbox. This process is automatic. 0000003791 00000 n Hamzeh Ramadan, Waste Stabilization Ponds - San Diego State University 0000006296 00000 n [11 0 R 12 0 R] Design must be carried out by expert. EMERY, R. Wastewater for treatment in aerobic ponds should have a BOD5 content below 300 mg/l (SASSE 1998). Advantages Disadvantages Low energy usage (feeding by gravity) Robust against load fluctuations . The effluent still contains nutrients (e.g. ()#2mVA'IQ>iJ\&6!K,\/H}Ku3 Qg5#C'N2Qc#l^U$q &n?Sdogl(a0wALSv>oQ;nqs}cHG endobj endobj Waste Stabilization Pond - Akvopedia Corinna: a. PDF Universities of Leeds, Sheffield and York http://eprints.whiterose.ac.uk/ The stabilization pond is located in the natural environment, and the climate has a great effect on it . Table 15 provides a comparison of the advantages and disadvantages of ponds with those of high-rate biological wastewater treatment processes. 7 0 obj Untitled Document [water.mecc.edu] 9 0 obj stream facultative pond advantages and disadvantages myer hr contact Stabilization ponds are a very promising sustainable centralized wastewater treatment option for West Africa due to the favourable climate. According to the International Water and Sanitation Centre (IRC), stabilisation ponds are the most cost-effective (semi-)centralised wastewater treatment technology for the removal of pathogenic microorganisms. endobj Dissolved oxygen is also provided by natural wind mixing. The effluent from lagoon systems can be suitable for irrigation (where appropriate), because of its high-nutrient and low pathogen content. Both have to deal with aeration of the water being treated, but in ponds, oxygen is transferred directly into the water across the surface area without the need for any equipment. PDF Secondary Wastewater Treatment (Waste Stabilization Ponds) aspects and provides practical information on design, financing and planning of faecal sludge treatment plants. 3 0 obj Table 1 provides a comparison of the advantages and disadvantages of ponds with those of high-rate and low-rate biological wastewater treatment processes (note that Aereated Lagoon and WSP system are considered low-rate biological wastewater treatment processes). At peak sun radiation, the pond will be mostly aerobic due to algal activity, while at sunrise the pond will be predominantly anaerobic (ERTAS et al. HWn9 ycf2l2k//%qM7db afUS?_$/X{x Waste Stabilization Ponds: A Design Manual for Eastern Africa. The direction from import to export should avoid the prevailing local wind direction throughout the year to prevent odor pollution . The oxygenation of the aeration pond is the same as other aerobic processes . HWr x}tliU@$f/G9EPrT\i HW~B$4vfzWe NwN:3yNRGJC?@B! 0000007068 00000 n endobj endobj endobj The wind has an important effect on the behavior of facultative ponds, as it induces vertical mixing of the pond liquid. Waste Stabilization Ponds and Constructed Wetlands Manual. macrophyteor fish ponds). Please enable JavaScript on your browser and try again. xref In cold climates, the HRT and loading may be adjusted. 0000001295 00000 n Some of AIWPS applications are given, emphasizing removal efficiencies in every unit. y"wmlVUvC Lagoon Technology International, RPI The technical content was reviewed by Prof. Duncan Mara (University of Leeds, England). FPs loose ammonia into the air at high pH; and settle some nitrogen and phosphorus in the sludge. 2. The main advantage of anaerobic ponds in a system is that they reduce by as much as 50% the land required for the facultative pond. N-^WJCQoU8lgL^laYXk lq5!JWDlpDS|WqxHlwaB#5nJy>y8b5:ypcluxqu6/*W!9?G! 11 0 obj The entire depth of this fairly deep man-made lake is anaerobic. Lagoons are one of the most popular methods for wastewater treatment around . Pond Treatment Technology. Anaerobic ponds are built to a depth of 2 to 5 m and have a relatively short detention time of 1 to 7 days. (2014): };kj?c?k'1$ . You'll get a detailed solution from a subject matter expert that helps you learn core concepts. Bekldve: 2022. mjus 29. vasrnap Szerz: . Pre-treatment (see Pre Treatment Technologies) is essential to prevent scum formation and to hinder excess solids and garbage from entering the ponds. IT experts - since 1997. However, when mean temperatures fall below 12 C during several month of the years, WSPs seem not to be appropriate (ARTUHR 1983). The major disadvantages of WSPs are a rather long process of days to week (MARA & PEARSON 1998;ROSE 1999) and requirement of large areas of land far away from homes and public spaces for the construction (DEPARTMENT FOR INTERNATIONAL DEVELOPMENT1998). endobj The anaerobic pond must be de-sludged approximately once every 2 to 5 years, when the accumulated solids reach one third of the pond volume. <> Stabilisation ponds also have the advantage of very low operating costs since they use no energy compared to other wastewater treatment technologies and only low-tech infrastructure (see also operation and maintenanceand ensuring sustainability). 0000000016 00000 n @,HZK[%w{(>;K7 u("(PgPJhPZeV+Ni9Z;uu7MW]C~~ncyEwv Stabilization ponds are the preferred wastewater treatment process in developing countries, where land is often available at reasonable opportunity cost and skilled labour is in short supply. However, this depends on the availability of land and its price. endobj ADVANTAGES AND DISADVANTAGES Some advantages and disadvantages of facultative lagoons are listed below: Advantages Moderately effective in removing settleable solids, BOD, pathogens, fecal coliform, and ammonia. <>/Font<>/ProcSet[/PDF/Text/ImageB/ImageC/ImageI] >>/MediaBox[ 0 0 720 540] /Contents 4 0 R/Group<>/Tabs/S/StructParents 0>> xMk@s;_ XVi&mRob #zg "Q*> endobj TVmfn $sx3s \y4 0000003742 00000 n Case Study of the Facultative Lagoon System, Gestin de agua y saneamiento sostenible en zonas rurales, http://www.lagoonsonline.com/clinton-water-district.htm, Settle undigested material and non-degradable solids as bottom sludge, Break down biodegradable organic material, Further treat wastewater through sedimentation and aerobic oxidation of organic material, Reduce some disease-causing microorganisms if. The major variants of pond systems are fully covered, namely: facultative ponds, anaerobic ponds, aerated lagoons, maturation ponds. <> trailer In particular, the appendix and annex provide a working example and a simple methodology to help the designer in preparing adequately detailed designs. % syO@\-{|D++]DFQ5;qk61I\+9L,gSxcHM]R)7Bi0K(KH\>O-ygm 7}WND>Z[VJZYQpFeBzVV\ Oxygen is unable to be maintained at the lower layers if the pond is too deep, and the colour too dark to allow light to penetrate fully or if the BOD and COD in the lower layer is higher than the supply. EAWAG (Swiss Federal Institute of Aquatic Science and Technology), Dorothee Spuhler (seecon international gmbh), Resistant to organic and hydraulic shock loads, High reducution of solids, BOD and pathogens, High nutrient removal if combined with aquaculture, No real problems with flies or odours if designed and maintained correctly, Can be built and repaired with locally available materials, Effluent can be reused in aquaculture or for irrigation in agriculture, High capital cost depending on the price of land, Sludge requires proper removal and treatment, If the effluent is reused, salinity needs to be monitored, Not always appropriate for colder climates. W&+I4@aI\'@ 1992) and anaerobic ponds do not or only rarely contain algae. 5 Stabilizing the pond body and its inlet and outlet, (1) Design points of the stabilization pond. Facultative waste stabilization ponds, sometimes referred to as lagoons or ponds, are frequently used to treat municipal and industrial wastewater in the . 1. endstream endobj 52 0 obj<. Very simple. endobj The anaerobic pond is the primary treatment stage and reduces the organic load in the wastewater. <>stream An aerated lagoon can usually discharge throughout the winter while discharge may be prohibited from an ice-covered facultative . 2008). Due to the algal activity, pH rises leading to inactivation of some pathogens and volatilisation of ammonia. These systems are composed of a series of ponds: (1) anaerobic ponds, (2) facultative ponds, and (3) maturation ponds. 0000003867 00000 n <> facultative pond advantages and disadvantages - Zolucky.sale (= Integrated Environmental Technology Series <>stream 12 0 obj The stabilization pond is located in the natural environment, and the climate has a great effect on it . The inlet and outlet should adopt multi-point water inlet and multi-point water outlet to make the water distribution on the cross section of the pond as even as possible . In contrast of waste stabilisation ponds where the oxygen required for stabilising the organic matter is furnished by algae, the oxygenation is provided in Aerated . 3. Wastewater treatment - Food and Agriculture Organization The design of the pond body should consider impact resistance and damage resistance . Photosynthetic algae release oxygen into the water and at the same time consume carbon dioxide produced by the respiration of bacteria. (1992): Whereas anaerobic and facultative ponds are designed for BOD removal, maturation or polishing ponds are essentially designed for pathogen removal and retaining suspended stabilised solids (MARA et al. High efficiency while very simple operation and maintenance. Stabilization Ponds . 3m away from the pond surface . W&+I4@aI\'@ Common Lagoon Problems, Two Montana Towns Use Lagoons, For More Information. [/PDF/Text/ImageB/ImageC] This paper shows that there are comprehensive experiences and available technologies that meet new and sustainable sanitation requirements. This publication deals with the feasibility of waste stabilisation ponds for the simultaneous treatment of collected sludge (by vacuum trucks) and wastewater from the domestic sewer system. Please enable cookies on your browser and try again. endobj (b) (i) Considering the discharge of organic effluent into a river, compare the processes of reaeration of the stream and the rate of decomposition of the organic waste for the four different zones of the polluted stream Require little energy, with systems designed to operate with gravity flow. facultative pond advantages and disadvantages - Abconsultant.pk Advantages. What are lagoon systems?, Advantages and Disadvantages of Lagoon Systems, Two, Three or Four Lagoons are Better than One, Facultative Lagoons Treat Wastewater Naturally, Lagoons Use Simple Design, Lagoons Need Proper Operation, Maintenance, . Sludge can be removed by using a raft-mounted sludge pump, a mechanical scraper at the bottom of the pond or by draining and dewatering the pond and removing the sludge with a front-end loader. The 55 chapters are divided into 7 parts over two volumes: Volume One: (1) Introduction to wastewater characteristics, treatment and disposal; (2) Basic principles of wastewater treatment; (3) Stabilisation ponds; (4) Anaerobic reactors; Volume Two (also available in the SSWM library): (5) Activated sludge; (6) Aerobic biofilm reactors; (7) Sludge treatment and disposal. Lagoon systems can be cost-effective to design and construct in areas where land is inexpensive. PEARSON, H. 1992; SASSE, 1998; TILLEY et al. Wastewater Use in Agriculture, Compendium of Sanitation Systems and Technologies (Arabic), Epuration des eaux uses par Lagunage a Microphytes et a Macrophytes en Afrique de l'Ouest et du Centre- Etat des lieux, performances puratoires et critres de dimensionnement, How to Select Appropriate Technical Solutions for Sanitation, Environmentally sound technologies in wastewater treatment for the implementation of the UNEP/GPA "Guidelines on Municipal Wastewater Management", Lagunas de Estabilizacion para Descarga de Liquidos de Camiones Atmosfericos, Ecological Sanitation and Reuse of Wastewater. ADVANTAGES AND DISADVANTAGES Some advantages and disadvantages of TFs are listed below. <> <> To prevent leaching, the ponds should have a liner. <> Various case studies on the reuse of pond and lagoon treated water in urban agriculture. Rensselaer Polytechnic Institute (RPI), SHILTON, A. There are three types of ponds, (1) anaerobic, (2) facultative and (3) aerobic (maturation), each with different treatment and design characteristics. 2nd Revised Edition, Biological Wastewater Treatment in Warm Climate Regions Volume 1, Training Material on Anaerobic Wastewater Treatment, Greywater Management in Low and Middle-Income Countries, Review of Different Treatment Systems for Households or Neighbourhoods, Guidance Manual on Water Supply and Sanitation Programmes, Advanced Integrated Wastewater Pond Systems, Waste Stabilization Ponds and Constructed Wetlands Design Manual, Design Manual for Waste Stabilization Ponds in Mediterranean Countries. 2 0 obj %PDF-1.3 Volume II of the Guidelines for the safe use of wastewater, excreta and greywater provides information on the assessment and management of risks associated with microbial hazards and toxic chemicals. series of vertical and horizontal-flow planted soil filters). ti raleigh 40th anniversary replica. This compendium gives a systematic overview on different sanitation systems and technologies and describes a wide range of available low-cost sanitation technologies. b) Facultative Pond, and The major topics covered are: microbiology and ecology of wastewater treatment, reaction kinetics and reactor hydraulics, conversion of organic and inorganic matter, sedimentation, aeration. PEARSON, H.W. (We`ll never share your email address with a third-party.). <> It explains requirements to promote the safe use of wastewater in agriculture, including minimum procedures and specific health-based targets, and how those requirements are intended to be used. Waste Stabilization Ponds (WSPs) are large, man-made water bodies. oKz~[_Zn[U/_Z x2}[[oJ.O_[/k^m~|5J~[\%{Z NCh{!@8]{p.9x^AA* yU2)GbD_.GZ d[GO[tZWv/uK^iMn ^4tM4_i_ B[T[oa0k*ov{k}GIW ePRw4aW/L&i rkUd $_L}~NTA~u]oN2 _____ The design principle of the water inlet is: for a general rectangular pond, the water inlet should be set at 1/3 of the length of the pond . What are the advantages and disadvantages of these three Waste Stablization Ponds listed below: a) Anaerobic Pond, b) Facultative Pond, and c) Aerobic Pond This problem has been solved! endstream 2003-2023 Chegg Inc. All rights reserved. Wind energy is one of the important auxiliary energy sources of the stabilization pond. October 13, 2010 no comments. (2003): Community-Based Technologies for Domestic Wastewater Treatment and Reuse- options for urban agriculture, Index of dept/chem-eng/Biotech-Environ/FUNDAMENT. Dar es Salaam/Copenhagen: Blackwater, Faecal Sludge, Greywater, Brownwater, Faeces, Excreta, Sludge, Fertigation Water, Biogas (if anaerobic pond is covered). As a complete process, the anaerobic pond serves to: BOD removal in anaerobic ponds is governed by the same mechanisms that occur in all other anaerobic reactors (MARA et al. The process (as in septic tanks) relies on the sedimentation of settable solids and subsequent anaerobic digestion in the resulting sludge layer. endobj facultative pond advantages and disadvantages They are simple to operate and maintain and generally require only part-time stuff. clarins or charlotte tilbury. )?0 f (X$y!9'yBvV2Aj=y +eNkp4BA4Y]@@")t` VZgk8C=lTe57t)MWZdN*84z27BZb"*PFymyj]UxJndu {z,B2Y\jkU5^IwYf0i4jfm]pRwI 5|Y0##ju?iV/HUsLgNWnf.0ykr&^:]?+dg"#{!K8?~yO?=~RJ{/6jo1eH98J^0z25&\N;2^,<7G(lH=Nh`/w=epGE +Y&\pgc6+V:P#ZGU_ ZvQ z s_:n*yU!2]WYy\=M56mzWKYx"gR[5] %-&: YfsQqrll1 SbRQrUpIo^NcRj? (9k|6m}ue|dU?1gXD.Rw Tv}~MF+_HW#?xWe8&. <> The advantages of mass communication are as follows. Wastewater Technology Fact Sheet Facultative Lagoons
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