Resumen En un experimento a escala piloto desarrollado en Brasil, se cultivaron juveniles de tilapia genéticamente mejorada en efluente de tanque séptico seguido de laguna de alta tasa (LAT). Durante las 22 semanas de la investigación se evaluó la combinación de tres tasas de aplicación superficial de nitrógeno amoniacal total (NAT) (0,6; 1,2 y 2,4 kg NAT.ha-1.d-1) y tres densidades de cultivo (3; 6 y 12 peces.m-2). Los tanques de cultivo funcionaron como unidades de pulimento para tratamiento de las aguas residuales, adicionando (con los mejores resultados, alcanzados con la menor densidad de cultivo y 1,2 kg NAT.ha-1.d-1) las siguientes eficiencias de remoción adicionales a las obtenidas mediante el uso de la LAT: 78,3% para nitrógeno total Kjeldahl; 89,1% para nitrógeno amoniacal; 63,9% para fósforo total; 57,2% para demanda química de oxígeno; 2,36 unidades logarítmicas para E. coli. La productividad de los peces se estimó del orden de 2,67 ton.ha-1 para cultivo durante seis meses por año para climas templados, utilizando la población de plancton natural del agua residual doméstica tratada como la única fuente de alimento.

Abstract In a pilot-scale experiment carried out in Brazil, genetically improved farmed tilapia juveniles were reared in septic tank-high rate algal pond (HRAP) effluent. The combination of three total ammonia nitrogen (TAN) surface loading rates (0.6; 1.2 and 2.4 kg TAN.ha-1.d-1) and three fish stocking densities (3; 6 and 12 fish.m-2) was evaluated during a 22-week research. The fish rearing tanks worked as wastewater treatment polishing units, adding (as the best results, achieved with the lowest fish stocking density and 1.2 kg TAN.ha-1.d-1) the following removal figures on top of those achieved at the HRAP: 78.3% total Kjeldahl nitrogen; 89.1% ammonia nitrogen; 63.9% total phosphorous; 57.2% chemical oxygen demand; 2.36 log units E. coli. Fish productivity was estimated at 2.67 ton.ha-1 for fish culture over six month per year in a temperate climate region, using the domestic treated wastewater natural plankton population as the only food source.

Resumo O tanque séptico é comumente utilizado para o tratamento de efluentes domésticos, especialmente em tratamentos descentralizados, no entanto ele requer manutenção periódica, incluindo a remoção, o tratamento e a disposição do lodo, o que pode ser difícil e custoso. Uma abordagem alternativa, alinhada aos princípios da economia circular, é o uso de unidades de gestão de lodo wetlands (UGLW). Neste estudo, foi realizado um experimento em escala de bancada utilizando seis UGLW (0,0177 m2 cada uma), plantadas com Canna x generalis. Foram testadas diferentes cargas de sólidos totais (ST) (15, 28 e 42 kg ST m-2 ano-1) e níveis de saturação (0,10 e 0,20 m), e uma estratégia de supercarga foi adotada no início da operação. O monitoramento e as análises foram realizados nos primeiros 150 dias de operação. Os resultados demonstraram que, já no início da operação, foram obtidas altas eficiências de remoção, especialmente nas unidades com nível de saturação de 0,20 m, atingindo 80% para ST, 93% para demanda química de oxigênio, 98% para nitrogênio total Kjeldahl e 97% para ortofosfato. Este trabalho mostrou que as UGLW são capazes de realizar um tratamento de alto nível, mesmo com cargas elevadas de sólidos no início da operação. Além disso, esses resultados indicam que cargas ainda maiores podem ser testadas para otimizar o desempenho do tratamento e reduzir a demanda de área. Assim, a configuração das UGLW, bem como as estratégias operacionais adotadas neste artigo, pode ser utilizada em pesquisas futuras, de longo prazo e em grande escala, para melhor compreender os mecanismos ativos de tratamento. domésticos descentralizados periódica remoção custoso alternativa circular UGLW. . (UGLW) estudo 0,0177 00177 0 0177 (0,017 m uma, , uma) generalis (ST 15, 15 (15 2 4 m- ano1 ano 1 ano-1 0,10 010 10 (0,1 020 20 0,2 m) operação 80 93 oxigênio 98 97 ortofosfato disso área Assim artigo futuras (UGLW 0,017 0017 017 (0,01 (1 ano- 0,1 01 (0, 02 0, 8 9 0,01 001 (0,0 ( (0 0,0 00

Abstract The septic tank is commonly used for treating domestic effluents, especially decentralized treatment. However, it requires periodic maintenance, including the removal, treatment, and disposal of sludge, which can be difficult and costly. An alternative approach, aligned with the principles of the circular economy, is the use of wetlands sludge management units (WSMU). In this study, a bench-scale experiment was conducted using six WSMU (0.0177 m2 each) planted with Canna x generalis. Different total solids (TS) loads (15, 28, and 42 kg TS m-2 year-1) and saturation levels (0.10 m and 0.20 m) were tested, and a super-loading strategy was adopted at the beginning of the operation. Monitoring and analyses were carried out over the first 150 days of operation. The results demonstrated that already at the beginning of the operation, high removal efficiencies were obtained, especially in units with a 0.20 m saturation level, reaching 80% for TS, 93% for chemical oxygen demand, 98% for total Kjeldahl nitrogen, and 97% for orthophosphate. This work showed that WSMU are capable of a high level of treatment even with high solids loads at the beginning of operation. Furthermore, these results indicate that even larger loads can be tested to optimize treatment performance and reduce area demand. Thus, the WSMU configuration, as well as the operational strategies adopted in this paper, can be used in future, long-term, and full-scale research to better understand the active treatment mechanisms. effluents However maintenance costly approach economy WSMU. . (WSMU) study benchscale bench scale 0.0177 00177 0 0177 (0.017 each generalis (TS 15, 15 (15 28 4 2 m- year1 year 1 year-1 0.10 010 10 (0.1 020 20 0.2 superloading super loading operation obtained 80 93 demand 98 nitrogen 97 orthophosphate Furthermore Thus configuration paper future longterm, longterm long term, term long-term fullscale full mechanisms (WSMU 0.017 0017 017 (0.01 (1 year- 0.1 01 (0. 02 0. 8 9 0.01 001 (0.0 ( (0 0.0 00

RESUMO Os wetlands construídos (WC) são uma ecotecnologia aplicável para o tratamento descentralizado de esgotos notadamente em pequenas comunidades, em razão de sua simplicidade operacional. Existem vários arranjos e combinações de WC possíveis, destacando-se o arranjo tanque séptico (TS), seguido da modalidade de WC de escoamento vertical (WCV) com recirculação do efluente do WCV de volta para o TS, como proposta para possibilitar a remoção de nitrogênio presente no esgoto afluente. Entretanto, no Brasil, essa configuração e suas implicações operacionais e de desempenho são pouco exploradas. Diante disso, o objetivo deste trabalho foi avaliar o desempenho de um sistema de TS seguido de um WCV com recirculação no tratamento descentralizado de esgoto doméstico. O sistema empregado no tratamento de esgoto de um equivalente populacional de dez habitantes é composto de um TS (4,7 m3 de volume útil), seguido de um WCV (24,5 m2 de área superficial) preenchido com brita e plantado com Canna spp. O monitoramento, que compreendeu um período de nove meses, teve início após um ano e cinco meses de operação do sistema. Utilizando taxa de 50% de recirculação, taxa de aplicação hidráulica no WCV de 85 mm d-1 e carga de 47 g DQO m-2.d-1, foram obtidas boas eficiências para remoção conjunta de demanda química de oxigênio — DQO (80%), sólidos em suspensão totais — SST (85%) e nitrogênio total —NT (42%), mesmo com elevadas cargas orgânicas. Além das boas eficiências apresentadas, o sistema demonstrou ser robusto e de operação simples e representa uma alternativa tecnológica com potencial para o tratamento descentralizado de esgotos de empreendimentos habitacionais.

ABSTRACT Constructed wetland (CW) is an applicable eco-technology for decentralized wastewater treatment, notably in small communities, due to its operational simplicity. CW has several possible arrangements and combinations, among which the septic tank (ST) stands out, followed by the vertical flow constructed wetland (VFCW), with treated effluent recirculation back to the ST to enable nitrogen removal. However, in Brazil, this configuration and its operational and performance implications are little explored. Therefore, this study aimed to evaluate the performance of an ST system, followed by a VFCW with recirculation in the decentralized treatment of domestic wastewater. The wastewater treatment system for 10 inhabitants consists of an ST (4.7 m3 of useful volume), followed by a VFCW (24.5 m2 of surface area) planted with Canna spp. The monitoring, which covered a period of nine months, started after one year and five months of system operation. Using a 50% recirculation rate, VFCW hydraulic loading rate of 85 mm d-1, and organic load of 47 g COD m-2 d-1, good efficiencies were obtained for the joint removal of chemical oxygen demand — COD (80%), total suspended solids — TSS (85%), and total nitrogen — TN (42%), even with high organic loads. In addition to the good efficiencies presented, the system proved to be robust and easy to operate, representing a technological alternative with potential for the decentralized wastewater treatment of housing developments.

Resumen En Costa Rica, el 70.9% de la población utiliza el tanque séptico como sistema de tratamiento individual a las aguas residuales domésticas. A pesar de que los tanques sépticos son la tecnología de tratamiento más utilizada en el país, no se cuenta con información detallada acerca de su funcionamiento y su eficiencia. Además, labores de mantenimiento, como lo es la remoción de lodos sépticos, son ejecutadas directamente por cada familia que usa este sistema y sin que exista un protocolo de limpieza unificado. La evaluación de estos sistemas se llevó a cabo en sistemas de tratamiento fabricados por una de las empresas privadas más importantes del país. Cada equipo evaluado consistía en un tanque séptico y un filtro anaerobio de flujo ascendente (FAFA) para el tratamiento de aguas residuales domésticas. La caracterización incluyó aspectos físicos, químicos y biológicos de la calidad y cantidad del agua residual producida en tres sistemas de tratamiento distintos, considerando variaciones horarias, así como la calidad y la cantidad de lodos acumulados en cada sistema. Los sistemas de tratamiento estaban instalados en dos edificios multifamiliares y una casa unifamiliar. Los resultados indicaron que los sistemas de tratamiento son muy sensibles en cuanto a cantidad y calidad del agua residual, presentando variaciones horarias significativas y además, afectadas por el tipo de uso de agua que se da en los hogares; lo cual está directamente relacionado al funcionamiento del tratamiento.

Abstract In Costa Rica, 70.9% of the population uses the septic tank as an individual treatment system for domestic wastewater. Although septic tanks are the most used treatment technology in the country, there is no detailed information about their operation and efficiency. The maintenance tasks, such as the removal of septic sludge, was carried out directly by each family that uses this system, using their own resources. The evaluation was carried out in treatment systems manufactured by one of the most important private companies in the country. Each equipment consists of a septic tank and an upflow anaerobic filter for the treatment of domestic wastewater. The evaluation included a physical, chemical and biological characterization of the quality and quantity of wastewater produced in three different treatment systems, considering hourly variations, as well as the characterization of the quality and quantity of sludge accumulated in each system. The treatment systems were installed in two multifamily buildings and a singlefamily house. The results indicated that the treatment systems are very sensitive in terms of quantity and quality of wastewater, presenting significant hourly variations and also affected by the type of water use that occurs in homes; which is directly related to the operation of the treatment.

Resumo Devido à carência de saneamento básico no Brasil, muitas habitações realizam o tratamento descentralizado de esgotos sanitários. Assim, estudos de custo das alternativas de tratamento são importantes. Uma análise do custo do ciclo de vida foi realizada para investigar o custo dos sistemas wetlands construídos para o tratamento de esgoto sanitário, comparando três cenários com as configurações mais comuns utilizadas. O cenário 1 foi constituído por uma ETE em escala real, localizada no sul do Brasil, composta de um tanque séptico e de um WCFV com recirculação ao tanque séptico. Os demais cenários foram criados: o cenário 2 foi formado por um WCFV, e o cenário 3 foi composto de um tanque séptico, um WCFV e um WCFH. Os valores presentes líquidos obtidos pela análise do custo do ciclo de vida para os cenários 1, 2 e 3 foram decrescentes. O cenário 3 apresentou menor custo do ciclo de vida. O cenário 1 foi o pior em relação à análise, entretanto, devido à utilização da recirculação, este apresentou melhor desempenho ambiental. A análise do custo do ciclo de vida, por levar em conta os custos ao longo da vida útil, mostrou-se uma ferramenta importante e adequada para a escolha da forma de tratamento de menor custo.

Abstract Due to the lack of basic sanitation in Brazil, many households use decentralised treatment of their wastewater. Therefore it is important to analyse the costs of wastewater treatment alternatives. A life cycle cost assessment was performed to evaluate the cost of constructed wetlands for wastewater treatment, comparing three scenarios with the most commonly used configurations. Scenario 1 consisted of a real scale wastewater treatment plant composed of a septic tank and a vertical flow constructed wetland with effluent recirculation to a septic tank, located in south of Brazil. The other two scenarios were created: scenario 2 was formed by a vertical flow constructed wetland and scenario 3 consisted of a septic tank, a vertical flow constructed wetland and a horizontal flow constructed wetland. The results showed that the net present value of the life cycle cost were decreasing for scenarios 1, 2 and 3. Scenario 3 presented lower life cycle cost. Scenario 1 had the poorest performance in the analysis, however, due to the recirculation of the wastewater this was the best performance in environmental terms. Due to the fact that life cycle cost analysis takes into account the cost throughout the life cycle of each scenario, it proved to be an important and suitable tool to help choosing the lowest cost treatment type.

ABSTRACT Objective To carry out a socioeconomic, demographic and parasitological evaluation of quilombola communities in two of the oldest municipalities in Brazil. Material and Methods Between December 2015 and June 2016, of the total of 231 residents of the communities, socioeconomic questionnaires were applied and fecal samples collected from 150 individuals were analyzed by spontaneous sedimentation method and the Kato-Katz method. Results It was observed that 95.3% (n=143) of the interviewees had piped water at their residence, and 76% (n=114) came from wells or springs; 85.3% (n=128) reported that the toilet drain was made in a rudimentary septic tank and 59.3% (n=89) reported having litter buried or burned, showing precarious conditions in basic sanitation. Still on socioeconomic aspects, 80.7% (n=121) of the individuals reported having access to the public health service. Parasitological tests were positive for 48% (n=72) of the analyzed samples, and 25% (n=18) had two or more parasites. The most frequent organism in the study population was the commensal Entamoeba coli (55.6%, n=40), followed by Ascaris lumbricoides (19.4%, n=14) and the commensal Endolimax nana (16.7%, n=12). The Poisson regression showed an increase of 1.59 in the prevalence of parasites for individuals who do not have access to the public health service, when compared to those who have access to these services. Conclusions The results indicate the need to implement public health measures in order to reduce, prevent and treat the parasitological condition of the population to obtain better conditions and quality of life.

RESUMEN Objetivo Realizar una evaluación socioeconómica, demográfica y parasitológica de las comunidades quilombolas en dos de los municipios más antiguos de Brasil. Materiales y Métodos Entre diciembre de 2015 y junio de 2016, del total de 231 residentes de las comunidades, se aplicaron cuestionarios socioeconómicos y se analizaron muestras fecales de 150 individuos mediante el método de sedimentación espontánea y el método Kato-Katz. Resultados Se observó que el 95,3% (n=143) de los entrevistados tenían agua entubada en su residencia y el 76% (n=114) provenía de pozos o manantiales; El 85,3% (n=128) informó que el desagüe del inodoro se realizó en un tanque séptico rudimentario y el 59,3% (n=89) informó que tenía basura enterrada o quemada, que mostraba condiciones precarias en el saneamiento básico. Aún en aspectos socioeconómicos, el 80,7% (n=121) de las personas reportaron tener acceso al servicio de salud pública. Las pruebas parasitológicas fueron positivas para el 48% (n=72) de las muestras analizadas, y el 25% (n=18) tenía dos o más parásitos. El organismo más frecuente en la población de estudio fue el comensal Entamoeba coli (55.6%, n=40), seguido de Ascaris lumbricoides (19.4%, n=14) y el comensal Endolimax nana (16.7%, n=12). La regresión de Poisson mostró un aumento de 1,59 en la prevalencia de parásitos para las personas que no tienen acceso al servicio de salud pública, en comparación con aquellos que tienen acceso a estos servicios. Conclusión Los resultados indican la necesidad de implementar medidas de salud pública para reducir, prevenir y tratar la condición parasitológica de la población para obtener mejores condiciones y calidad de vida.

ABSTRACT Fish processing requires large amounts of water, which is used in equipment washing and in raw material cleaning. In addition water is used as storage and cooling mean before and during processing. The Business Unit of Base (UEB) "Induvilla", in Santa Clara, lacks of an adequate liquid residuals treatment system. The purpose of this research is to propose an adequate system for liquid residuals treatment. Annually this entity has a consumption of 21200 m3 of water and generates 67.45 m3 / day of liquid waste with high pollutant load. The values of COD and BOD5 determined were 1000 and 486 mg / L, respectively, which violate NC 27: 2012. For this reason, the implementation of an anaerobic-facultative lagoons system is required to remove 90% of the BOD5, the system will occupy an area of 228.3 m2. The installation could be carried out 200 meters from the outlet of the residuals from the septic tank where there is a terrain, rectangular with an area of 160 x 500 meters. To transport the waste, an SMF 200/2 / 2-80H A0CT-EX pump will be used. The total investment estimated for the treatment system is $ 13749.83.

RESUMEN El procesamiento del pescado requiere grandes cantidades de agua, la cual se emplea en el lavado de los equipos y la limpieza de la materia prima, además de servir como medio para el almacenamiento y la refrigeración antes y durante el procesamiento. La Unidad Empresarial de Base (UEB) “Induvilla”, en Santa Clara, carece de un sistema adecuado para el tratamiento de los residuales líquidos que genera. Esta investigación tiene como finalidad proponer un sistema adecuado para el tratamiento de los residuales líquidos. Anualmente esta entidad tiene un consumo de 21 200 m3 de agua y genera 67,45 m3/día de residuales líquidos con alta carga contaminante. Los valores de DQO y DBO5 determinados fueron 1 000 y 486 mg/L, respectivamente, los cuales incumplen la NC 27:2012. Por tal motivo se requiere la implementación de un sistema de lagunas anaerobia-facultativas para remover el 90% de la DBO5, el sistema ocupará un área de 228,3 m2. La instalación se pudiera realizar a 200 metros de la salida de los residuales del tanque séptico donde se cuenta con un terreno, de forma rectangular con un área de 160 x 500 metros. Para transportar el residual se utilizará una bomba SMF 200/2/2-80H A0CT-EX. La inversión total estimada para el sistema de tratamiento es de $ 13749,83.

RESUMEN Objetivo Realizar una evaluación socioeconómica, demográfica y parasitológica de las comunidades quilombolas en dos de los municipios más antiguos de Brasil. Materiales y Métodos Entre diciembre de 2015 y junio de 2016, del total de 231 residentes de las comunidades, se aplicaron cuestionarios socioeconómicos y se analizaron muestras fecales de 150 individuos mediante el método de sedimentación espontánea y el método Kato-Katz. Resultados Se observó que el 95,3% (n=143) de los entrevistados tenían agua entubada en su residencia y el 76% (n=114) provenía de pozos o manantiales; El 85,3% (n=128) informó que el desagüe del inodoro se realizó en un tanque séptico rudimentario y el 59,3% (n=89) informó que tenía basura enterrada o quemada, que mostraba condiciones precarias en el saneamiento básico. Aún en aspectos socioeconómicos, el 80,7% (n=121) de las personas reportaron tener acceso al servicio de salud pública. Las pruebas parasitológicas fueron positivas para el 48% (n=72) de las muestras analizadas, y el 25% (n=18) tenía dos o más parásitos. El organismo más frecuente en la población de estudio fue el comensal Entamoeba coli (55.6%, n=40), seguido de Ascaris lumbricoides (19.4%, n=14) y el comensal Endolimax nana (16.7%, n=12). La regresión de Poisson mostró un aumento de 1,59 en la prevalencia de parásitos para las personas que no tienen acceso al servicio de salud pública, en comparación con aquellos que tienen acceso a estos servicios. Conclusión Los resultados indican la necesidad de implementar medidas de salud pública para reducir, prevenir y tratar la condición parasitológica de la población para obtener mejores condiciones y calidad de vida.

ABSTRACT Objective To carry out a socioeconomic, demographic and parasitological evaluation of quilombola communities in two of the oldest municipalities in Brazil. Material and Methods Between December 2015 and June 2016, of the total of 231 residents of the communities, socioeconomic questionnaires were applied and fecal samples collected from 150 individuals were analyzed by spontaneous sedimentation method and the Kato-Katz method. Results It was observed that 95.3% (n=143) of the interviewees had piped water at their residence, and 76% (n=114) came from wells or springs; 85.3% (n=128) reported that the toilet drain was made in a rudimentary septic tank and 59.3% (n=89) reported having litter buried or burned, showing precarious conditions in basic sanitation. Still on socioeconomic aspects, 80.7% (n=121) of the individuals reported having access to the public health service. Parasitological tests were positive for 48% (n=72) of the analyzed samples, and 25% (n=18) had two or more parasites. The most frequent organism in the study population was the commensal Entamoeba coli (55.6%, n=40), followed by Ascaris lumbricoides (19.4%, n=14) and the commensal Endolimax nana (16.7%, n=12). The Poisson regression showed an increase of 1.59 in the prevalence of parasites for individuals who do not have access to the public health service, when compared to those who have access to these services. Conclusions The results indicate the need to implement public health measures in order to reduce, prevent and treat the parasitological condition of the population to obtain better conditions and quality of life.

Resumen Se pretende analizar la cobertura de acceso a agua de calidad potable y saneamiento en aguas residuales domésticas, para proponer las metas de país a cumplir en el 2022 y 2030 en el marco del Objetivo 6 de los “Objetivos de Desarrollo Sostenible”. Para lograrlo se cumplieron 5 etapas, que abordan la cobertura y calidad del agua para consumo humano, el saneamiento en aguas residuales domésticas, un resumen sobre el Programa Nacional de Mejoramiento y Sostenibilidad de la Calidad de los Servicios de Agua Potable (PNMSCSAP), la propuesta del Programa Nacional de Manejo Adecuado de Aguas Residuales (PNMAAR) y las metas a cumplir con ambos programas para los años 2022 y 2030, respectivamente. En el 2016 la población de Costa Rica alcanzó 4.889.762 habitantes, cubierta con agua por AyA, Municipios, acueductos rurales, entre otros. La potabilidad fue del 91,8 % y el 99,5% de la población cuenta con agua por tubería, para un total de 1.878 acueductos potables y 696 no potables. El mejoramiento en la calidad del agua se hace manifiesto durante el transcurso de los años, con algunos eventos de contaminación de origen químico. En total 5.222 fuentes se evaluaron durante el 2016, prevaleciendo el uso de nacientes. El 74,1% de la población del país es abastecida con agua sujeta a control de calidad y el 86,3% a tratamiento y/o desinfección. La disposición de excretas en Costa Rica se realiza a través de tanque séptico en 76,6%, un 21,3% por alcantarillado o cloaca (8,2% con tratamiento), 1,9% por otros sistemas y 0,2% no cuentan con sistema de disposición de excretas. Se propone la implementación y sostenibilidad de dos iniciativas, el PNMSCSAP y el PNMAAR, con la intención de contribuir a mejorar los indicadores de calidad del agua y la salud pública del país, considerando los aportes de otros programas como “Bandera Azul Ecológica” y “Sello de Calidad Sanitaria”. Por otro lado, se debe continuar realizando ese tipo de estudios, pero adoptando una visión más integral e interinstitucional, que permita ampliar el ámbito de acción.

Abstract The study aims to analyze the drinking-water coverage and sanitation in domestic wastewater, in order to stablish the 2022 and 2030 country targets within the framework of Objetive 6 of the “Sustainable Development Objectives”. Five stages were developed: coverage and drinking-water quality, domestic wastewater sanitation, summary of the National Program for the Improvement and Sustainability of the Quality of the Services for Drinking-water (PNMSCSAP), the proposal of the National Program for Wastewater Management (PNMAAR) and the goals to be fulfilled with both programs for 2022 and 2030, respectively. In 2016, the costarrican population supplied with drinking-water by AyA, Municipalities, rural aqueducts, among others, was about 4,889,762 inhabitants. The potability was 91.8% and 99.5% of the population received water per pipeline; with 1,878 aqueducts and 696 non-potable water. Drinking-water quality has improved along the years, in spite of certain chemical pollution events. A total of 5,222 water sources were evaluated during 2016, with the use of spring sources prevailing. Water quality control was applied to aqueducts, wish provided drinking-water to 74.1% of the country´s population. The 86.3% of the population was supplied with treated or disinfected drinking-water. In Costa Rica, 76.6% of excreta disposal was carried out through septic tanks, 21.3% through sewer (only 8.2% received treatment), 1.9% through other systems, and 0.2% lacked excreta disposal systems. In order to improve the country´s water quality and sanitation, two initiatives were proposed: PNMSCSAP and PNMAAR. The programmes “Bandera Azul Ecológica” and “Sello de Calidad Sanitaria” should be included within this scheme. Futher studies with a wider approach are needed.

RESUMO Objetivou-se, com a realização deste estudo, avaliar a qualidade físico-química e microbiológicas dos frutos do mamoeiro Tainung 1, produzidos mediante proporções de tempo de irrigação com água de abastecimento (AA) e esgoto doméstico tratado em tanque séptico seguido de filtros anaeróbios (AE). O delineamento experimental utilizado foi o de blocos casualizados com quatro tratamentos e seis repetições. Os tratamentos foram compostos por T1 (100% de AA mais adubação recomendada), T2 (67% de AA mais 33% AE), T3 (33% AA mais 67% AE) e T4 (100% de AE). A qualidade físico-química e microbiológica dos frutos foi avaliada por meio dos seguintes parâmetros: espessura da polpa (EP), firmeza da polpa (FP), teor de sólidos solúveis totais (SS), pH, acidez titulável (AT), relação SS/AT e nível populacional de Salmonella ssp. e coliforme totais. Observou-se que as proporções de tempo de irrigação com AA e AE aplicadas não proporcionaram alterações, significativas, nas características físico-químicas dos frutos do mamoeiro, indicando que os valores encontrados atendem aos padrões exigidos para a comercialização e consumo in natura. A qualidade microbiológica dos frutos do mamoeiro produzidos com AE é aceitável para consumo humano, uma vez que, foi constatada a ausência de Salmonella ssp. e de coliformes totais.

ABSTRACT When carrying out this study, the aim was to evaluate physicochemical and microbiological quality in fruit of the papaya Tainung 1, produced under different irrigation time ratios with water from the supply (AA) and from domestic sewage which had been treated first in a septic tank and then with anaerobic filters (AE). The experimental design was of randomised blocks, with four treatments and six replications. The treatments consisted of T1 (100% AA plus a recommended fertiliser), T2 (67% AA plus 33% AE), T3 (33% AA plus 67% AE) and T4 (100% EA). The physicochemical and microbiological quality of the fruit was evaluated using the following parameters: pulp thickness (EP), pulp firmness (PF), total soluble solids (SS), pH, titratable acidity (TA), SS to AT ratio and the population levels of Salmonella ssp. and total coliforms. It was found that the applied irrigation time ratios with AA and AE resulted in no significant changes to the physicochemical characteristics of the papaya fruit, showing that the values obtained meet the standards required for marketing and in natura consumption. The microbiological quality of papaya fruit produced with AE is acceptable for human consumption, as there was an absence of Salmonella sp. and total coliforms.

Abstract In the community of Pulinguí belonging to the parish of San Andrés del canton Guano province of Chimborazo-Ecuador, domestic sewage is treated in a system of septic tanks and upward filter, which presents problems of bad smell and low reduction of organic matter. The objective of the present work was to evaluate at laboratory scale the efficiency of pollutant removal by combining the current anaerobic treatment with an aerobic treatment by activated sludge. A prototype with 27.9 liters capacity was designed, built and operated, of which 15.8 liters correspond to the anaerobic zone, 7.7 liters to the aeration zone and 4.4 liters to the sedimentation zone. The system was evaluated for 60 days with domestic wastewater from the cited community. During the evaluation, daily pH and dissolved oxygen determinations were performed, and the Chemical Oxygen Demand (COD) was determined twice a week. The information generated allowed us to observe that the system tended to stabilize during the three weeks of operation, achieving organic removal efficiencies in terms of COD in the anaerobic treatment of 53%, in the aerobic treatment of 75%, achieving a total reduction in The entire 88% system and eliminating the odor. With data from the anaerobic tank taken after 60 days of continuous work, it allowed to project the maintenance of the Pulinguí treatment plant the same that must be realized in approximately each 4 years.

Resumen En la comunidad de Pulinguí perteneciente a la parroquia de San Andrés del cantón Guano provincia de Chimborazo, Ecuador se tratan las aguas residuales domésticas en un sistema de tanques sépticos y filtro ascendente, que presentan problemas de mal olor y baja reducción de la materia orgánica. El presente trabajo analiza la eficiencia de remoción de estos contaminantes al combinar el tratamiento anaerobio actual con un tratamiento aerobio por lodos activados en un prototipo a escala de laboratorio. Se diseñó, construyó y operó un prototipo con 27.9 litros de capacidad, de los cuales 15.8 L corresponden a la zona anaeróbica, 7.7 L a la zona de aireación y 4.4 L a la zona de sedimentación. El sistema fue evaluado durante 60 días con agua residual doméstica proveniente de la comunidad citada. Durante la evaluación se realizaron diariamente determinaciones de Ph, sólidos suspendidos y oxígeno disuelto, así mismo se determinaron dos veces por semana la Demanda Química de Oxígeno (DQO). La información generada permitió observar que el sistema tendió a estabilizarse durante la semana tres de operación, alcanzando eficiencias de remoción de materia orgánica en términos de DQO en el tratamiento anaeróbico de 53%, en el tratamiento aeróbico de 75%, logrando una reducción total en todo el sistema del 88% y eliminando el olor. Con datos del tanque anaeróbico tomados después de 60 días de trabajo continuo, se permitió proyectar el mantenimiento de la planta de tratamiento de Pulinguí el mismo que debe realizarse en aproximadamente cada 4 años.

Abstract : This paper makes a comparative analysis between the Dipole-dipole, Wenner and Schlumberger arrays through electric resistivity tomography (ERT), about the sensitivity and resolution in the spatial characterization of infiltrating pollutants in septic tank and cone of depression in supply well, both contained in unconfined aquifer. Data acquisition consisted of electrical resistivity rea- dings using five parallel lines with 105m long, electrode spacing and lines of 5m. The data from each line were subjected to 2D inversion and then interpolated to generate 3D blocks, which were extracted from a fixed resistivity isosurface (620 Ω.m), which enabled the modeling of volumes related to the flow structures. The results for the Dipole-dipole array allowed the modeling of the cylindrical structure associated to the supply well, and an isosurface deformation associated to the septic tank, but did not allow the modeling of the plume. The data for the Schlumberger array cannot allow for the cone recognition, but resulted in a drop shape model, associated to the septic tank and similar to a contamination plume. The Wenner array resulted in a model with structure in elongated keel format associated to the cone of depression, and another that is similar to the drop shape model, also associated to the septic tank. The comparative analysis shows that the Dipole-dipole array is recommended in works of modeling vertically integrated three- dimensional structures of high resistivity in the saturated zone. The Wenner and Schlumberger arrays are recommended for modeling vertically integrated three-dimensional structures of low resistivity in unsaturated zone, with emphasis on the Schlumberger array.

Resumen: En este trabajo se hace un análisis comparati- vo entre los arreglos Dipolo-dipolo, Wenner e Schlumberger por medio de pruebas de Tomo- grafía de Resistividad Eléctrica (TRE), como la sensibilidad y la resolución en la caracterización espacial de la infiltración de contaminantes en un tanque séptico y cono de depresión en el pozo de captación de agua; ambos contenidos en acuífero libre. La adquisición de datos consistió en lecturas de resistividad utilizando cinco líneas paralelas con 105 m de largo espaciado, 5 m entre los electrodos y líneas. Los datos de cada línea se sometieron a la inversión 2D, posteriormente interpolado para la generación de bloques 3D, de la cual se extrajo una isosuperficie de resistividad fija (620 Ω.m), lo que permitió el modelado de las estructuras de volúmenes de flujo relacionados. Los resultados para el arreglo Dipolo-dipolo permite el modelado de la estructura asociada con el eje cilíndrico, y un isosurface de la cavidad asociada con la deformación, pero que no permitirá que el modelado de la pluma. Los datos para la disposición Schlumberger no pueden ser reconocidos cono, pero dieron lugar a un modelo de forma de lágrima asociado con el tanque séptico, como una pluma de contaminación. El arreglo Wenner resultó en un modelo con estructura en formato de quilla alargado asociado con el cono de depresión, y uno en formato caída similar también asociado con el tanque séptico. El análisis comparativo muestra que la disposición Dipolo-dipolo se recomienda en las obras de modelado de estructuras tridimensionales de alta resistividad verticales en la zona saturada. La disposición Wenner y Schlumberger se recomiendan en estructuras de modelado en tres dimensiones verticales de baja resistividad en zona no saturada, con énfasis en la disposición Schlumberger.

Resumen El objetivo del presente estudio fue determinar las coberturas y evolución del porcentaje de población con sistemas de disposición de excretas (DE) en Costa Rica en el periodo 20002014, según los diferentes mecanismos de evacuación como alcantarillado, tanque séptico, letrinas y otros, aunado al inventario y evaluación de la remoción de la Demanda Bioquímica de Oxígeno Total (DBO mg/L) y de Coliformes fecales (CF/100 mL), en los sistemas de tratamiento convencionales de aguas residuales a cargo del AyA y el análisis de las expectativas de cobertura con DE en el país para el año 2021. Para cumplir con el objetivo del estudio se aplicaron los siguientes pasos; primero, se analizaron las enfermedades vinculadas al contacto con las excretas; segundo, se definió el concepto de la UNICEF y la OMS de “Instalaciones de Saneamiento Mejoradas”; tercero, se describió la cobertura de la población del país con DE mediante alcantarillado, tanques sépticos, letrinas y otros, tanto a nivel nacional como regional y en la zona rural y urbana, en el año 2014; cuarto, se realizó un inventario de los sistemas de tratamiento convencional de aguas residuales y las eficiencias con la remoción de DBO total y CF/100 mL en las aguas crudas y tratadas controladas por el Laboratorio Nacional de Aguas, en el mismo año 2014; quinto, se realizó un análisis de la evolución de las coberturas de DE con los diferentes mecanismos de evacuación durante el periodo 2000-2014; por último, como sexto punto, se establecieron las expectativas de DE por alcantarillado y tanques sépticos para el año 2021. Se hizo un resumen de los factores vinculados a la transmisión de enfermedades infecciosas transmitidas a los seres humanos por contacto con excretas. Posteriormente, se definió el concepto de “Instalaciones de Saneamiento Mejoradas” de la UNICEF y la OMS. Con el desarrollo de los datos de cobertura de la población con DE en el 2014, se comprobó que el país cuenta con un 71,5% de habitantes con tanques sépticos, 26,6% con alcantarillado, 1,5% con letrinas y 0,4% no cuenta con ningún mecanismo de DE. Se elaboró un inventario de 58 sistemas de tratamiento de aguas residuales. Se determinaron las eficiencias de remoción de DBO total (mg/L) y CF/100 mL, comprobándose que solamente la laguna de estabilización de Santa Cruz cumple con el valor permitido de 50 mg/L en los efluentes tratados. En el caso de los sistemas de tratamiento convencionales, en su mayoría (78%) cumplieron con el valor permitido de DBO total establecido en la normativa nacional del 2010. Con respecto a la remoción de CF/100 mL, sin bien es cierto los porcentajes son altos (entre 90% y 100%), las elevadas densidades provocan un gran riesgo de contaminación en los cuerpos receptores utilizados en cada sistema. El análisis de la evolución del uso de los diferentes mecanismos de DE, en el periodo de estudio, demuestra un incremento en el uso de tanques sépticos en detrimento del uso de alcantarillado hasta el 2011; no obstante, a partir de 2012 se observa una leve reversión, y en 2014 los datos indican que el uso de tanque séptico bajó a 71,5%. Por último, el análisis de la ampliación del alcantarillado y tratamiento en los 11 cantones de San José permitirá alcanzar entre el 22% y el 25% de población con DE tratadas y un 50% a 53% en el uso de alcantarillado. Este avance permitirá disminuir el uso de los tanques sépticos al 50% en el año 2021. Conclusiones: De conformidad con el concepto de “Instalaciones de Saneamiento Mejoradas” de la UNICEF y la OMS, Costa Rica alcanzó un 99% de cobertura con DE mediante alcantarillado, tanques sépticos y letrinas, lo que ubica al país a la vanguardia de los países latinoamericanos. Sin embargo, esto es paradójico, debido a que el poco tratamiento de las aguas residuales con sistemas colectivos, o alcantarillado, ha provocado un gran deterioro de los ríos en las zonas urbanas. Recomendaciones. Es fundamental ampliar las coberturas de DE por alcantarillado sanitario con tratamiento, para sanear los ríos y otros cuerpos de agua superficiales y subterráneas; además, se debe implementar un Programa Nacional de Manejo Adecuado de las Aguas Residuales, planteando metas a mediano y largo plazo, con el propósito de mejorar la salud pública del país.

Abstract The present study aimed to establish excreta disposal coverage and progress in Costa Rica from 2000 to 2014, considering the different mechanisms for excreta evacuation (e.g. drainage, septic tank, and latrine), and assessing the removal of the Biochemical Oxygen Demand (BOD mg/L) and faecal coliforms (CF/100 mL) within conventional wastewater treatment systems managed by AyA. Likewise, the study aimed to assess the excreta disposal coverage expectations for 2021. Six steps were followed: 1) diseases linked to excreta transmission were analysed; 2) the concept of ‘Improved sanitation facilities’ established by the UNICEF and the WHO was defined; 3) the excreta disposal coverage was described according to the use of drainage, septic tanks, and latrines, in a centralise and decentralise level, and in urban or rural area during 2014; 4) a stock of wastewater conventional treatment systems were carried out together with the efficiency of BOD and faecal coliforms removal in wastewater and treated water controlled by the National Water Laboratory (LNA) in 2014; 5) an assessment of the progress of excreta disposal coverage along the different mechanisms for evacuation was carried out during the period 2000-2014; and 6) the expectations of excreta disposal by septic tanks or drainage were established for 2021. A summary was writing up concerning the factors linked to infectious disease transmission to humans by excreta contact. Subsequently, the concept of ‘Improved sanitation facilities’ established by the UNICEF and the WHO was defined. Based on the data development of the population with excreta disposal coverage in 2014, the study confirmed that 71,5 % of the costarican population possesses septic tanks, 26,6 % drainage, 1,5 % latrines, and 0,4 % lacks of any excreta evacuation mechanism. The stock presented 56 wastewater conventional treatment systems. Efficiency of BOD (mg/L) and coliforms faecal (CF/100 mL) removal were determined; none of the waste stabilization ponds complied with the maximum limit value (50 mg/L). Only 57 % of the 14 activated sludge treatment systems complied with the BOD allowed value established on the national normative in 2010. Coliform faecal removal percentages were high (90 % - 100 %); although, increased density of microorganisms can cause high risk of water sources pollution. The analysis of the progress of the different excreta disposal mechanisms during 2000-2014 showed a rise in the use of septic tanks, during 2000-2011. In 2012 a low reversion was observed, and in 2014 the use of septic tank was reduced to 71,5 %. Finally, an analysis of the enlargement of the drainage and water treatment within 11 municipalities in San José will allow to reach 22 - 25 % of the population with treated excreta disposal, and 50 - 53 % in the use of drainage. This will allow the reduction of the use of septic tanks to 50 % for 2021. Conclusions: In accordance with the concept of ‘Improved sanitation facilities’, Costa Rica have reached 99 % of excreta disposal coverage due to the use of drainage, septic tanks and latrines. However, wastewater has received very little treatment (drainage and collective systems), causing great damage to the rivers within urban areas. Recommendations: It is crucial to enlarge excreta disposal coverage, increasing drainage and wastewater treatment, in order to clean up rivers and others superficial water bodies and aquifers. A National Programme for Suitable Wastewater Manager should be implemented contemplating medium and long term goals, in order to improve public health in Costa Rica.

RESUMO Objetivou-se, nesta pesquisa, estudar os efeitos da irrigação com esgotos tratados e da adubação nitrogenada nos atributos químicos de um Luvissolo Crômico cultivado com algodoeiro herbáceo. Instalou-se um experimento em ambiente protegido, disposto em delineamento inteiramente casualizado com quatro repetições, em esquema fatorial 5 x 4. Foram testados cinco doses de adubação nitrogenada (0, 45, 90, 135 e 180 kg ha-1) associadas a quatro fontes de água de irrigação (água do sistema de abastecimento público, efluente de esgoto tratado em reator anaeróbio, efluente tratado em reator anaeróbio e pós-tratado em filtros de areia intermitentes em série e efluente tratado em tanque séptico e pós-tratado em filtro de areia intermitente). Procedeu-se à irrigação diária de julho de 2011 a janeiro de 2012 com base na demanda hídrica da cultura do algodoeiro, com lâmina total de 620 mm. Constatou-se, em relação ao manejo convencional com água de abastecimento, que a irrigação com esgotos tratados proporciona maior acúmulo de micronutrientes, potássio e sódio no solo, elevando os riscos de sodificação em áreas irrigadas.

ABSTRACT The objective of this research was to investigate the effects of irrigation with treated wastewater and nitrogen (N) fertilization on the chemical characteristics of a Haplustalf soil cultivated with cotton. An experiment was conducted in a greenhouse in a completely randomized design with four replicates, and arranged in a 5 x 4 factorial. Five doses of N fertilization (0, 45, 90, 135 and 180 kg ha-1) and four sources of irrigation water (freshwater, wastewater treated by an anaerobic reactor, wastewater treated by an anaerobic reactor and post-treated by intermittent sand filter in series, wastewater treated in a septic tank and post-treated by an intermittent sand filter) were tested. Irrigation was daily performed from July 2011 to January 2012 according to the water demand of cotton resulting in a water depth of 620 mm. It was found that, compared with the conventional management with freshwater irrigation, treated wastewater provides greater accumulation of micronutrient, potassium and sodium in the soil, increasing the risk of sodification in irrigated areas.

Resumo A destinação dos Lodos de Fossa e Tanque Séptico (LFTS) tem resultado em problemas ambientais e de saúde pública, devido principalmente à falta de alternativas adequadas para a destinação, e de fiscalização mais rigorosa. O problema se agrava em municípios desprovidos de estações de tratamento de esgoto, já que a disposição nesses sistemas tem sido a prática mais utilizada no país. Desta forma, a presente pesquisa teve por finalidade avaliar os efeitos da disposição desses lodos no desempenho, operação e manutenção de lagoas de estabilização que tratam lixiviados. O sistema estudado é composto por dois módulos idênticos de lagoa anaeróbia seguida de facultativa, de modo que o módulo receptor de LFTS foi submetido, durante seis meses, a diferentes taxas de aplicação volumétrica de lodo por lixiviado (13 a 204%). Utilizou-se o teste t de Student, para a análise estatística. Os resultados indicaram que, para a taxa máxima, o efluente do módulo receptor apresentou concentrações 1,8; 2,0; e 9,0 vezes superiores ao testemunho, para fósforo, nitrogênio amoniacal e E. coli, respectivamente. Além disso, houve aumento de lodo sedimentado na lagoa anaeróbia receptora (3,5 vezes em relação à testemunho) e formação de escuma (0,4 m3 por mês). Entretanto, as interferências na operação e manutenção são de simples solução, pois esses resíduos podem ser destinados no próprio aterro e os padrões de lançamento em corpos hídricos não foram contrariados. Desta forma, as lagoas de estabilização que tratam lixividados apresentam-se como uma alternativa competitiva para a destinação dos LFTS, resguardadas as condições operacionais estudadas.

Abstract The destination of septage has resulted in environmental and public health problems, due especially to the lack of adequate alternatives for its destination and of closer, more rigorous monitoring. The problem worsens in areas lacking sewage treatment plants, since the disposal in such systems has been the most widely used practice in the country. In this way, the current research aims to evaluate the effects of the sludge disposal in the performance, operation and maintenance of waste stabilization ponds that treat landfill leachate. The treatment system studied is composed by two modules of identical anaerobic ponds followed by facultative ponds. For six months, the receiver modul was submitted to different rates of volumetric sludge application by leachate (13 to 204%). Student's t test was used for statistics analysis. The results indicated that for the maximum rate, the receiver module effluent showed concentrations 1.8; 2.0; and 9.0 times higher than the control modul, phosphorus, ammonia nitrogen and E. coli, respectively. In addition, there was an increase in the sedimented sludge in the receiving anaerobic pond (3.5 times in relation to the control group) and scum formation (0.4 m3 per month). However, the interferences in the operation and maintenance have simple solutions, since these residues may be sorted in the landfill itself and the release patterns in water bodies were not thwarted. In this way, the stabilization ponds that treat leachate present a competitive alternative for the destination of septage, safeguarding all operating conditions studied.