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International audience; Home composting systems (HC) are known to facilitate municipal solid waste management, but little is known about their environmental impact including their greenhouse gas emissions (GGE). The present research focused on selecting HC configuration producing the least CH4 and N2O. Thus, 4 HC types were used to compost food and yard waste for 150 days and monitored for CO2, CH4 and N2O as of day 15: the wood and plastic bins (WB and PB), the mixed and unmixed ground pile (GPM and GP). Using the same waste recipe, all HC were filled at once (batch fed) to maximize gaseous emissions. Weekly as of day 15, CO2, N2O and CH4 emissions were measured during 2-h sessions using a closed chamber inserted into the compost surface. Monitored compost characteristics indicated little differences over time except for moisture content. From day 15 to 150, CH4 emissions were not measurable. Generation of N2O occurred between day 20 and 120 with PB producing the least because of top and bottom slots providing continuous convective aeration, as compared to the WB with slats over its full height and the naturally aerated mixed and unmixed ground piles. Total N2O emissions of 56 kg CO2-eq (tonne wet waste treated)-1 for PB, 75 for GP, 97 for WB and 99 for GPM represented average value for centralized composting facilities. Present and past scientific works suggest the need for more research to establish the combined effect of management and HC configuration on gaseous emissions, with close CH4 measurements from day 0 to 15. © 2012 Elsevier Ltd.

International audience; Within cities around the world, home composting can reduce the cost of disposing food waste (FW) and yard trimmings (YT). Besides reducing equipment and labour costs, home composting of organic waste eliminates its selective collection and mechanical processing, and reduces the fossil fuel required for these tasks as well as their resulting greenhouse gases. Nevertheless, the successful implementation of onsite composting depends on the active participation of households and the production of a safe soil amendment. The research objectives of the project were therefore to define the operational parameters which optimize the composting process and quality. The research work was first initiated in the laboratory, at the IRSTEA (formerly Cemagref) Research Centre, of Rennes, France, using typical home composting systems (HC) loaded with an organic waste mixture consisting of equal volumes of wet FW and YT. During this experiment, the ground pile, the slatted wood bin, the plastic bin and the rotary drum were compared using different management practices (batch versus weekly feeding, weekly mixed versus not mixed, and with or without wood chips as bulking agent, BA); home composter performance was compared in terms of dry matter (DM), carbon and nitrogen mass balance, and pathogen/parasite counts. These laboratory results were validated during a second experiment conducted with the collaboration of 5 households of Montreal, Canada, where slatted and top/bottom perforated plastic bins were normally loaded and operated by the residents during the summer, while being monitored for temperature, mass loading and compost quality. The laboratory results indicated that bin perforation had a significant impact on compost decomposition: concentrating the perforations at the top and bottom of the bin optimized convective aeration, but concentrated the decomposition at the bin bottom. Weekly mixing and good aeration also helped produce higher compost temperatures. Bulking agent addition retarded the composting process. Compost temperature regime and bin aeration or mixing had little effect on final compost quality and pathogen/parasite counts. For the experiment conducted with 5 households of Montreal, Canada, the best location for the home composter was found to be in a semi-shaded area. Once more, bins with perforations concentrated at their top and bottom produced the highest compost temperatures. Weekly loaded all bins did produce thermophilic temperatures, unless loaded with at least 10 kg of organic waste/week at over 15% DM. Despite compost temperatures seldom reaching thermophilic levels, pathogens were minimized in the final product with good bin aeration fostering a high level of organic waste degradation. To minimize the content of metals and toxic organics in the final product, the feed stock should be clean; the use of back yard herbicides and insecticides should be minimized.

[Departement_IRSTEA]Ecotechnologies [TR1_IRSTEA]TED; International audience; This study investigated the influence of composting aeration rate on emission concentrations in terms of ammonia, hydrogen sulphide, mercaptan, and Volatile Organic Compounds (VOCs). The influence of the aeration on the gaseous emission was the first process conditions investigated. Organic waste composting generates emissions resulting in a significant level of nuisance often leading to conflicts closing or preventing the installation of treatment plants. Ammonia, hydrogen sulphide and VOCs are the main contributors to compost odours. Conventional solutions are designed to confine the odours or apply a biological or chemical treatment. By establishing the relationship between aeration rate and compost gaseous emission characteristics, preventive control techniques can be introduced. The project investigated the influence of the aeration rate on compost emissions from pig slaughterhouse sludge, using 300 L pilots reactors under forced aeration. Five different rates were tested: 1.68, 4.03, 6.22, 9.80 and 13.04 L/h/kg of wet waste. The aeration treatment was applied to the same waste mixture consisting of Pig Slaughter house Sludge (PSS) and Wood Chips (WC), mixed at a dry mass ratio of 1.2:1(PSS:WC). The Wood Chips (WC) came from the same plot of calibrated 20-40 mm particle size. All experimental materials were analyzed and weighed before starting the experiment. Composting treatments were aerated during 30 to 60 days, and the material was turned every 10 days. The aeration rate was maintained constant while monitoring the compost temperature. The incoming and outgoing ventilation air streams were monitored for O2, CO2 and CH4. A portion of the outgoing ventilation air stream was also bubbled into chemical traps for NH3, H2S and mercaptan quantification. Every two days, another portion of the outgoing ventilation air stream was collected using Tedlar bag and its gases trapped on activated carbon trap to analyze its VOC by Gas Chromatography coupled with a Mass Spectrometry (GC/MS); qualification and quantification of VOCs were obtained by chromatogram processing. At the end of the experiment, all reactors were emptied, to weigh and sample their content for a mass balance analysis. In terms of composting emissions, over 45 VOCs were identified and classified based on their concentration: major constituents (nitrides, sulphides, ketones and alcohols); average constituents (nitride and sulphide compounds, aromatic hydrocarbons and aliphatic hydrocarbons), and minor constituents (terpenes, alkanes, and acids). The concentration of these compounds was based on the concentration over time per kg organic matter of initial wet PSS waste within the air flow rate. The analysis of emission concentrations indicated that higher aeration rates increased emissions, but had no influence on the final waste stability simply because low rates resulted in a longer treatment period and more turning operations. Thus, higher aeration rate enhanced the stripping of gases from the compost matrix. Nevertheless, increasing the aeration rate changed the emission profile with higher rate producing emission peaks rather than an even profile associated with the lower aeration rates. As a result, an aeration strategy must be considered to optimize the treatment of gaseous emissions from pig slaughterhouse sludge composting plant.

International audience; Society is reconsidering composting, this ancient technology, for the treatment and recycling of municipal organic wastes. Municipalities are now encouraging the use of home composting when very little is known about the environmental impact of this practice as compared to other more conventional means. Furthermore, there is a need to establish a standard method to evaluate the impact of such a practice, when the diversified tools presently used produce data which cannot be compared. Within the European LIFE project Miniwaste, a study was conducted to establish a standard method to evaluate the mass and composition of the treated biowaste. The experimented method used a combination of well recognized tools: conducting household surveys; getting households to measure the mass of biowaste (BW) fed into the composters, and; measuring household waste production and its residual organic fraction (ROF). The study of the results obtained thanks to these different tools enabled to propose a simplified protocol that will then be used by other municipalities to assess the impact of home composting in their own communities and compare their results with other European regions. The study was conducted in the sector of Cesson Sévigné, a suburb of the City of Rennes, France. Within the 1000 households contacted, all living in individual homes, 300 were surveyed to characterize their organic waste (OW) management practices. People of 60 years and over were found to be most likely to practice composting. The telephone survey was also used as a simple tool to recruit households to further the study and monitor the mass and type of biowaste actually composted. Accordingly, 38 households volunteered (VH) to weight their fed biowaste during one year: the OW originated either from their kitchens or their yards. 4 parallel campains of household waste characterization (one per season) were conducted. The amounts of organic waste still present in the bins are recorded according to the bio-waste management reported by households. Groups were established to separate households that compost and weigh their composted waste (VH) from, those who compost but do not weigh their waste (NVH) and those who do not compost. The statistical analysis of the results determined differences due to the seasons, to the fact of being weighing volunteers or to practice or not home-composting. It appears that each individual assessment tool does not provide a complete response to the evaluation. Therefore the coupling of several tools is recommended. Finally, the method proposes to implement a survey and measure the output per capita for households 'composters' and 'non-composters.

Interim 2-[18F]Fluoro-2-deoxy-D-glucose Positron Emission Tomography performed after two chemotherapy cycles (PET-2) is the most reliable predictor of treatment outcome in ABVD-treated Hodgkin Lymphoma (HL) patients. We retrospectively analysed the treatment outcome of a therapeutic strategy based on PET-2 results: positive patients switched to BEACOPP, while negative patients continued with ABVD. Between January 2006 and December 2007, 219 newly diagnosed HL patients admitted to nine centres were enrolled; 54 patients, unfit to receive this treatment were excluded from the analysis. PET-2 scans were reviewed by a central panel of nuclear medicine experts, according to the Deauville score (Meignan, 2009). After a median follow up of 34 months (12-52) the 2-year failure free survival (FFS) and overall survival for the entire cohort of 165 patients were 88% and 98%; the FFS was 65% for PET-2 positive and 92% for PET-2 negative patients. For 154 patients in which treatment was correctly given according to PET-2 review, the 2-year FFS was 91%: 62% for PET-2 positive and 95% for PET-2 negative patients.this strategy, with BEACOPP intensification only in PET-2 positive patients, showed better results than ABVD-treated historic controls, sparing BEACOPP toxicity to the majority of patients.

International audience; Urban organic waste (UOW) represents one of the major components of the municipal solid waste (MSW) mainstream. Being the most biologically active fraction and once landfilled, UOW generates greenhouse gases contributing to global warming. Considering such environmental issue, the European Union has set a diversion goal of 65 % for the biodegradable fraction of MSW by 2016. Since modern centralized organic waste treatment systems have an important economic impact even on developed countries, more practical but just as safe solutions are needed. In this context, the onsite composting of food and yard trimmings using home systems (HC) can divert from landfills significant amounts of urban organic wastes. However, few studies pertain to the environmental and sanitary issues resulting from such practice. The aim of this study was to quantify the greenhouse gas (CO2, N2O and CH4) emissions and the pathogen and parasite content of the matured compost produced by HC. This study selected three of the most popular HC with a useful capacity of 320 L: slatted plastic bin; slatted wooden bin, and; ground pile. Each compost system received 60 kg of mixed food waste and yard trimmings. The gaseous emissions from each HC were measured using a closed hood and analysed by gas chromatography (GC). The composts were mixed weekly and sampled for analysis on days 0, 15, 30 and 150. During the active composting phase, the highest CO2 emissions were produced during the thermophilic period from all three HC while the maximum N2O emissions were observed after the mesophilic period. The CH4 emissions were too limited to be measured by gas chromatography. After 150 days of composting, the mature product offered parasite and pathogen levels within standard limits accepted France and North America.

International audience; In developed countries such as those of the european Union, stringent legislations for the recycling of urban organic waste (UOW) have forced municipalities to reconsider traditional practices and seek environmental solutions with a minimum economic impact. As an alternative to centralized composting or anaerobic digestion facilities increasing collection and management costs, the onsite-treatment of UOW using home composting methods (HC) can eliminate transportation and labour costs. Nevertheless, HC needs to be managed in such a way as to produce a sanitary product. This study evaluated the performance of four different HC as compared to a laboratory compost reactor with forced aeration. During the first two weeks of active composting for all four HC, temperatures exceeding 55ºC demonstrated an active microbial community likely stabilizing the waste and reducing its parasite and pathogen levels. After 150 days, the mature compost from all HC exhibited 15 to 20% moisture content except for that of the rotating metallic drum, which remained at 77% because of blocked ventilation ports.

The 10th World Congress on Anaerobic Digestion, 29 August - 02 September 2004, Montreal, Canada

The characterization of food waste (FW) and locally available bulking agents (BA) are a prerequisite to optimizing compost recipes. This study measured the variation in FW characteristics (pH, dry matter (DM), carbon (C), wet bulk density and Total Kjeldahl Nitrogen (TKN)) produced by a restaurant and a community kitchen in downtown Montreal, Canada from May to August 2004. The project also measured the mass of FW produced by another restaurant and a group of 2048 households, from June to August 2004. Locally available BA (hay, straw, pine wood shavings, cardboard, left over cattle feed and wheat residue pellets) were also characterized to formulate composting recipes based on the FW characteristics observed during a period representative of winter and summer conditions. Residential and restaurant FW characteristics varied significantly over the summer months, although the mass produced remained constant at 0.61 and 0.56 kg capita1 day1, respectively. In addition, the number of customers served by the restaurant increased by nearly 50% from June to August. The BA with the highest moisture adsorption capacity was found to be the wheat residue pellets, followed by chopped straw. Wheat residue pellets, chopped hay and left over cattle feed all presented a balanced C/N ratio. Wheat residue pellets and wheat straw, chopped hay and cardboard demonstrated neutral pH values. Based on the variable FW characteristics and monthly production rates, the formulation of recipes indicates that compost facilities must be flexible enough to handle seasonal variations of as much as 50% by volume.

The characterization of food waste (FW) and locally available bulking agents (BA) are a prerequisite to optimizing compost recipes. This study measured the variation in FW characteristics (pH, dry matter (DM), carbon (C), wet bulk density and Total Kjeldahl Nitrogen (TKN)) produced by a restaurant and a community kitchen in downtown Montreal, Canada from May to August 2004. The project also measured the mass of FW produced by another restaurant and a group of 2048 households, from June to August 2004. Locally available BA (hay, straw, pine wood shavings, cardboard, left over cattle feed and wheat residue pellets) were also characterized to formulate composting recipes based on the FW characteristics observed during a period representative of winter and summer conditions. Residential and restaurant FW characteristics varied significantly over the summer months, although the mass produced remained constant at 0.61 and 0.56 kg capita1 day1, respectively. In addition, the number of customers served by the restaurant increased by nearly 50% from June to August. The BA with the highest moisture adsorption capacity was found to be the wheat residue pellets, followed by chopped straw. Wheat residue pellets, chopped hay and left over cattle feed all presented a balanced C/N ratio. Wheat residue pellets and wheat straw, chopped hay and cardboard demonstrated neutral pH values. Based on the variable FW characteristics and monthly production rates, the formulation of recipes indicates that compost facilities must be flexible enough to handle seasonal variations of as much as 50% by volume.

The characterization of food waste (FW) and locally available bulking agents (BA) are a prerequisite to optimizing compost recipes. This study measured the variation in FW characteristics (pH, dry matter (DM), carbon (C), wet bulk density and Total Kjeldahl Nitrogen (TKN)) produced by a restaurant and a community kitchen in downtown Montreal, Canada from May to August 2004. The project also measured the mass of FW produced by another restaurant and a group of 2048 households, from June to August 2004. Locally available BA (hay, straw, pine wood shavings, cardboard, left over cattle feed and wheat residue pellets) were also characterized to formulate composting recipes based on the FW characteristics observed during a period representative of winter and summer conditions. Residential and restaurant FW characteristics varied significantly over the summer months, although the mass produced remained constant at 0.61 and 0.56 kg capita1 day1, respectively. In addition, the number of customers served by the restaurant increased by nearly 50% from June to August. The BA with the highest moisture adsorption capacity was found to be the wheat residue pellets, followed by chopped straw. Wheat residue pellets, chopped hay and left over cattle feed all presented a balanced C/N ratio. Wheat residue pellets and wheat straw, chopped hay and cardboard demonstrated neutral pH values. Based on the variable FW characteristics and monthly production rates, the formulation of recipes indicates that compost facilities must be flexible enough to handle seasonal variations of as much as 50% by volume., En 2001, le Ministère de l'Environnement du Québec modifiait son règlement sur la gestion des fumiers à la ferme et exigeait le traitement des eaux usées de laiterie. Par conséquent, les entreprises laitières avec moins de 60 vaches se voyaient obligées d'investir plus de 15 000 $ Can. pour l'installation d'un système conventionnel de traitement de ces eaux usées. L'objectif du projet était donc de modifier le système de fosse septique et champ d'épuration pour pouvoir traiter à coût raisonnable les eaux usées de laiterie, tout en valorisant ces eaux et leurs nutriments. Sur deux fermes avec 40 et 50 vaches, un basin de sédimentation et de captage de gras fut installé en amont de la fosse septique existante, et un champ d'épuration drainé de 0,45 ha fut construit en aval de la fosse septique. Le projet consistait à: faire le suivi des champs d'épuration pour évaluer leur colmatage après deux ans d'opération; mesurer et échantillonner les eaux usées de laiterie pour établir leur charge annuelle en nutriment, élément qui dimensionne le champ d'épuration pour un traitement durable, et; faire le suivi des charges de contaminants évacués par le système de drainage du champ d'épuration qui assure son opération. En effectuant la moyenne des deux fermes, les eaux usées de laiterie offraient une charge annuelle de NT, PT et KT de 60, 50 and 80 kg ha-1 an-1, respectivement; le volume moyen généré était de 17,5 mm/mois, ce qui ne suffisait pas à colmater le champ d'épuration tel que constaté à la fin du projet. L'accumulation de gras dans les tuyaux du champ d'épuration d'une des fermes résultait de l'envoie de lait sale dans le système, l'absence d'adoucisseur d'eau dans la laiterie et le manque de nettoyage de la fosse à sédiments et gras. Le drainage du champ d'épuration assurait son bon fonctionnement sans décharger de charge contaminante dans les fossés environnants. Le système modifié ne coûtait que 4400 $ Can., et réussissait à traiter de façon durable les eaux usées des fermes laitières.

Dairy farms with as many as 200 cows still handle their wastewaters and solid manures separately. Because of the large volume produced and their low nutrient load, these dairy farm effluents (DE) are costly and time consuming to land spread using conventional equipment, such as the tanker. The purpose of this study was to test the equipment and cost to determine the cost of the equipment adapted for the simplified surface irrigation of DE and to establish best management practices to reduce risks of groundwater contamination. The project was conducted on two dairy farms in South Western of Montreal, Canada, where typical DE were applied to irrigated plots of 0.5 and 0.3 ha, respectively, and the groundwater quality was compared to a control plot of the same size. Groundwater quality was monitored for nutrients (total nitrogen, total phosphorus, total potassium and pH) and bacterial counts (total coliforms, faecal coliforms, and faecal streptococci). A manure pump and conventional water irrigation pipes were satisfactory in irrigating with the DE without clogging as long as the DE was collected in a tank separate from that of the solid manure. During all applications, subsurface seepage losses occurred, but these would not be lost to the watercourse when applied in quantities respecting irrigation guidelines and on soils where the groundwater table was at or below the depth of the subsurface drains. Nevertheless, these seepage losses represented less than 1% of the total volume of DE applied, and the seepage nutrient and bacterial load was generally less than half of that of the irrigated DE. The surface irrigation system reduced the cost of land spreading DE from CAN $3.25m3 (conventional tanker) to CAN $1.10m3 (surface irrigation). The heavy total potassium load of the DE requires the rotation of the irrigation plot, on an annual basis.

Dairy farms with as many as 200 cows still handle their wastewaters and solid manures separately. Because of the large volume produced and their low nutrient load, these dairy farm effluents (DE) are costly and time consuming to land spread using conventional equipment, such as the tanker. The purpose of this study was to test the equipment and cost to determine the cost of the equipment adapted for the simplified surface irrigation of DE and to establish best management practices to reduce risks of groundwater contamination. The project was conducted on two dairy farms in South Western of Montreal, Canada, where typical DE were applied to irrigated plots of 0.5 and 0.3 ha, respectively, and the groundwater quality was compared to a control plot of the same size. Groundwater quality was monitored for nutrients (total nitrogen, total phosphorus, total potassium and pH) and bacterial counts (total coliforms, faecal coliforms, and faecal streptococci). A manure pump and conventional water irrigation pipes were satisfactory in irrigating with the DE without clogging as long as the DE was collected in a tank separate from that of the solid manure. During all applications, subsurface seepage losses occurred, but these would not be lost to the watercourse when applied in quantities respecting irrigation guidelines and on soils where the groundwater table was at or below the depth of the subsurface drains. Nevertheless, these seepage losses represented less than 1% of the total volume of DE applied, and the seepage nutrient and bacterial load was generally less than half of that of the irrigated DE. The surface irrigation system reduced the cost of land spreading DE from CAN $3.25m3 (conventional tanker) to CAN $1.10m3 (surface irrigation). The heavy total potassium load of the DE requires the rotation of the irrigation plot, on an annual basis.

W. E. B. Du Bois once remarked that “It was in Germany that my first awakening to social reform began” (Aptheker 1982, p. 275). This essay examines the intellectual impact of Du Bois's voyage to Berlin from 1892 to 1894. His acquisition of empirical social research methods under the tutelage of German historical economists, particularly Gustav von Schmoller, armed him with the intellectual and methodological tools he needed in his effort to attack pervasive biological determinist theories in the United States. Using empirical techniques grounded in a “system of ethics” as his conceptual guideposts, Du Bois analyzed race as not a biological but a social phenomenon. To be sure, this was no easy task. He was also a “race man,” who, loyal to his moral commitment to building a program of racial uplift, sought legitimacy as a social scientist from his fellow American sociologists, who summarily ignored his work. Struggling to serve his roles as both scientist and race man, Du Bois functioned within an intellectual space of double consciousness, constantly vacillating between two communities and two voices. In the end, Du Bois would successfully bring the scientific method to the race question, using inductive methods in his sociological studies on the African American experience. This approach made possible his seminal work The Philadelphia Negro (1899) and, subsequently, his research at Atlanta University. In the final analysis, his empirical research stood its ground, successfully advancing a new paradigm for examining race based on the idea that the putative racial hierarchy, theoretically grounded in biological determinism, was nothing more than a social artifact buttressed by racism. He further demonstrated how the economic disparity between Whites and Blacks functioned as the prime catalyst for “a plexus of social problems” that plagued African American life (Du Bois 1898, p. 14). His conclusions were a radical departure from the work of many American sociologists, many of whom were sympathetic to social Darwinism—his most formidable challenge.This essay would not have been conceived without the steady support and constant pushing of my dear friends and colleagues, all of whom have read or heard this paper at various stages: Anne Harrington, Robert Brain, Stephen C. Ferguson, Fanon Che Wilkins, Craig Koslofsky, Matti Bunzl, Peter Fritzsche, Frederick Hoxie, Dianne Pinderhughes, Jason E. Glenn, Bernadette Atuahene, Adam Biggs, Charlton Copeland, and Bikila Ochoa.

Landfill gas emissions are one of the largest anthropogenic sources of methane especially because of food waste (FW). To prevent these emissions growing with world population, future FW best management practices need to be evaluated. The objective of this paper was therefore to predict FW production for 2025 if present management practices are maintained, and then, to compare the impact of scenario 1: encouraging people to stay in rural areas and composting 75% of their FW, and; of scenario 2, where in addition to scenario 1, composting or anaerobically digesting 75% of urban FW (UFW). A relationship was established between per capita gross domestic product (GDP) and the population percentage living in urban areas (%UP), as well as production of municipal solid waste (MSW) and UFW. With estimated GDP and population growth per country,%UP and production of MSW and UFW could be predicted for 2025. A relatively accurate (R 2 > 0.85) correlation was found between GDP and%UP, and between GDP and mass of MSW and FW produced. On a global scale, MSW and UFW productions were predicted to increase by 51 and 44%, respectively, from 2005 to 2025. During the same period, and because of its expected economic development, Asia was predicted to experience the largest increase in UFW production, of 278 to 416 Gkg. If present MSW management trends are maintained, landfilled UFW was predicted to increase world CH4 emissions from 34 to 48 Gkg and the landfill share of global anthropogenic emissions from 8 to 10%. In comparison with maintaining present FW management practices, scenario 1 can lower UFW production by 30% and maintain the landfill share of the global anthropogenic emissions at 8%. With scenario 2, the landfill share of global anthropogenic emissions could be further reduced from 8 to 6% and leachate production could be reduced by 40%.

When handled separately from manures, dairy farm effluents (DE) are costly to manage because of their low nutrient content and large volume. In anticipation of using surface irrigation to lower the land application cost of DE, this projects investigated the impact, on DE characteristics, of different sources and storage systems. Milk house wastewaters were monitored on two farms using a 500 l manhole intercepting these before entering the septic tank. Manure runoff, with and without milk house wastewater, was also characterised on six farms for 1 yr, and on two farms for three consecutive years, where each farm used a different management system. The results indicated that DE containing milk house wastewater, manure runoff or a mixture of both had a relatively low nutrient load, confirming that their application rate needed to range between 205 and 2050m3 ha-1, depending on the management system used. Stored along with solid manure, DE generally had a higher total solids (TS), nutrient loads and bacterial count, as compared to that drained away from the solid manure. Furthermore, for effluent drained away from solid manures, rainfall rather than snow occurring from October to May, inclusively, tended to increase their TS and nutrient load. The ratio of faecal coliforms to faecal streptococci (FC/FS) was greater than 10 when milk house wastewaters were stored along with the manure runoff because milk house wastewaters increased the death rate for FS compared to FC.

When handled separately from manures, dairy farm effluents (DE) are costly to manage because of their low nutrient content and large volume. In anticipation of using surface irrigation to lower the land application cost of DE, this projects investigated the impact, on DE characteristics, of different sources and storage systems. Milk house wastewaters were monitored on two farms using a 500 l manhole intercepting these before entering the septic tank. Manure runoff, with and without milk house wastewater, was also characterised on six farms for 1 yr, and on two farms for three consecutive years, where each farm used a different management system. The results indicated that DE containing milk house wastewater, manure runoff or a mixture of both had a relatively low nutrient load, confirming that their application rate needed to range between 205 and 2050m3 ha-1, depending on the management system used. Stored along with solid manure, DE generally had a higher total solids (TS), nutrient loads and bacterial count, as compared to that drained away from the solid manure. Furthermore, for effluent drained away from solid manures, rainfall rather than snow occurring from October to May, inclusively, tended to increase their TS and nutrient load. The ratio of faecal coliforms to faecal streptococci (FC/FS) was greater than 10 when milk house wastewaters were stored along with the manure runoff because milk house wastewaters increased the death rate for FS compared to FC.

First International Meeting on Environmental Biotechnology and Engineering (IMEBE), September 6-8, 2004, Mexico City, Mexico