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Sewage and Organic Wastes. TREN 3P14: Sustainable Integrated Waste Management David T. Brown. toxics nutrients suspended matter pathogens thermal pollution dissolved gases. anthropogenic origin (e.g. industrial effluent, municipal sewage, tourism operations)
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Sewage and Organic Wastes TREN 3P14: Sustainable Integrated Waste Management David T. Brown
toxics nutrients suspended matter pathogens thermal pollution dissolved gases anthropogenicorigin (e.g. industrial effluent, municipal sewage, tourism operations) naturalorigin (e.g. silt, mineral nutrients, wild animal wastes) Water Pollutants
Significant concern in the tourism industry • Water quality • Water quantity • Aesthetic concerns • Disease and pathogens • Local equity issues
Controlling Water Pollution • Upstream: before the problem occurs • Downstream: after the problem occurs
Upstream Methods of Controlling Water Pollution • process modification in industry: elimination of pollutants and toxics • avoidance of direct discharge into: • water bodies • storm sewers • sanitary sewers • identification of storm drains (e.g. Yellow Fish Road project)
Upstream Methods of Controlling Water Pollution • decoupling of storm and sanitary sewers • runoff control: • increasing absorptive surfaces • avoiding erosion • maintaining streambank and shoreline vegetation • legislation and regulation: guidelines and laws establishing limits on discharge
S E W A G E Neolithic revolution • small towns and settlements -> human waste control generally non-problematic
S E W A G E “In days of old When knights were bold And toilets weren’t invented They’d leave their loads Upon the roads And walk away contented.”
S E W A G E Post - Neolithic revolution: Large towns and cities -> human waste control became a problem high-density living required technologies for handling human wastes in urban areas: • chamber pots and open gutters • pit privies / trench latrines/ outhouses • septic systems and variants • centralized sewage collection and treatment systems
Temporary /short term: packing it out single-use holes pit privies trench latrines Downstream Methods of Managing Sewage: Small scale Meyer, Kathleen. 1989. How to shit in the woods : an environmentally sound approach to a lost art. Ten Speed Press, Berkeley, Calif.
Long-term outhouses settling ponds septic tanks septic fields composting toilets Downstream Methods of Managing Sewage: Small scale van der Ryn, Sim. 1978 (republished and revised 1999). The Toilet Papers: Recycling Waste and Conserving Water. Chelsea Green Publishing, Vermont. Online edition available atwww.brocku.ca/tren/courses/tren3p14/2006/ToiletPapers.pdf
Downstream Methods of Sewage Treatment • domestic sewage treatment: • preliminary: screening andremoval of large contaminants • primary: straining and settling of solids • secondary: removal of biodegradable organic matter and nutrients • tertiary: removal of residual dissolved nutrients and pollutants
Downstream Methods of Sewage Treatment • effluent treatment processes: • mechanical:filtering, gravity separation • chemical: flocculation, coagulation • biological:microbes or macrophytes aerobic or anaerobic • disinfection:chlorination, ozonation, etc. (pathogen control)
Downstream Methods of Sewage Treatment • ‘physical plant’/ ‘engineered’ approach(usually centralized, large scale) • ‘constructed wetland’ approach(centralized or decentralized, large or small scale)
GRIT CHAMBER SETTLING TANK CHLORINATION TANK BAR SCREEN outflow Primary Sewage Treatment Raw sewage Sludge SLUDGE DIGESTER SLUDGE DRYING BED
AERATION TANK GRIT CHAMBER SETTLING TANK SETTLING TANK 2 BAR SCREEN outflow Secondary Sewage Treatment Raw sewage CHLORINATION TANK Methane Air pump Activated sludge SLUDGE DIGESTER SLUDGE DRYING BED
Constructed Wetland EXPERIMENTAL CELLS S.W.A.M.P. (SEWAGE WASTE AMENDMENT MARSH PROJECT) Niagara on the Lake, Ontario
Constructed Wetland EXPERIMENTAL CELLS
Constructed Wetlandmacrophytes Cattails and Water Hyacinth
Large scale constructed wetland Saha Pat Industrial Park, Laem Chabang, Thailand
Settling tank Saha Pat Industrial Park, Laem Chabang, Thailand
Sludge dewatering and drying Saha Pat Industrial Park, Laem Chabang, Thailand
Aeration pond Saha Pat Industrial Park, Laem Chabang, Thailand
Outflow into constructed wetland Saha Pat Industrial Park, Laem Chabang, Thailand
Large scale constructed wetland Saha Pat Industrial Park, Laem Chabang, Thailand
Water and Legislation • multijurisdictional: federal, provincial, and municipal areas of responsibility • multifaceted: laws and regulations deal with • conservation and management of water resources; protection of aquatic life • pollution and liquid discharge • drinking water standards
Federal Water Legislation(in areas of federal jurisdiction) Canadian Environmental Protection Act (CEPA) :regulates the release of specified toxic substances, the concentration of nutrients in products (e.g. nitrates, phosphates); national regulations for pulp and paper mill effluents Fisheries Act: forbids the depositing of deleterious substances in any waters frequented by fish; regulates aquatic toxicity testing; regulates pulp and paper mill effluents and requires monitoring of effects on fish habitat
Provincial Water Legislation Ontario Water Resources Act: Section 30(1) prohibits the discharge of any material into any water body, shoreline, or bank that may impair the quality of the water Environmental Protection Act (EPA) :Subsection 14: prohibits discharge of any contaminant into the natural environment that causes or is likely to cause an adverse effect
Water Quality Guidelines, Policies, and Objectives: • cover water quality for many types of water uses and aquatic environments (e.g. water storage structures, sewage plant discharge, drinking water quality objectives and treatment requirements, etc.) • legally enforceable when incorporated into a Certificate of Approval or a Control Order Banned and Phased-Out Chemicals: • primary and secondary lists of substances to be banned, phased out, or reduced in use due to their persistence in water or aquatic systems
Drinking Water: Municipalities are responsible for conforming to provincial water quality and treatment guidelines for drinking water from surface and ground sources
MISA(Municipal, Industrial Strategy for Abatement) • program aimed at the virtual elimination of persistent toxic contaminants from all discharges into Ontario waterways • dealt with direct dischargers (into surface waters, e.g. sewage treatment plants, certain industries) and indirect dischargers (into municipal sewer systems).
Objectives: • identify and measure toxic substances in discharges • increase emphasis on control technlogy • pollution prevention and reduction in multi-media transfer of pollutants • strengthen abatement and enforcement mechanisms -> eventual virtual elimination of persistent toxic substances
Municipal-Industrial Strategy for Abatement Advisory Committee was eliminated by Harris government, and MISA program severely weakened. • Avenues for both public input and multi-stakeholder input to government decision-making were removed. Starting in 1995, the Harris Government weakened or revoked nearly every environmental protection law in Ontario and numerous regulations under these laws.
Every aspect of environmental protection was affected, including controls on air pollution, water pollution, pesticides, waste disposal and recycling, urban sprawl, energy use and climate change, natural heritage and biodiversity protection, mining, and forestry. DETAILS: • Canadian Environmental Law Association (http://www.cela.ca/): Environmental Deregulation in Ontario - 1996-2000http://62.44.8.131/coreprograms/detail.shtml?x=1780
Municipal Water Legislation Discharges to Sewers: Municipal sewer use by-laws regulate substances which can be discharged to sanitary, combined, or storm sewers. Based on MOE Model Sewer Use Bylaw. In absence of municipal by-laws, the Ontario Clean Water Agency regulated these parameters. Harris Government Bill 107 promoted privatization of municipal water and sewer infrastructure without voter assent. Budgets for monitoring and regulation were slashed.
Walkerton • E. Coli contamination of municipal water supply from cattle manure results in hundreds of illnesses and seven deaths, including two-year old child • Tragedy deemed preventable • Incompetent management by Koebel brothers (managers of water supply), lack of adequate water testing, excessive budget cutbacks and deregulation all identified as factors in tragedy
Further Details: • The Walkerton Tragedy: http://www.canoe.ca/EcoliTragedy/ • Walkerton Flash presentation:http://www.canoe.ca/EcoliTragedy/Walkerton.swf • Walkerton Inquiry report:http://www.attorneygeneral.jus.gov.on.ca/english/about/pubs/walkerton/part1/
2002: Tory government introduced • Safe Drinking Water Act • Sustainable Water and Sewage Systems Act to guard against another water tragedy like Walkertonhttp://www.ene.gov.on.ca/envision/water/sdwa/index.htm • Act authorized the government to implement key recommendations in Walkerton inquiry report
Acts criticized as inadequate, as source contamination concerns not addressed • Tories defeated in 2003 • Liberal government elected 2003 • Introduced Clean Water Act (Dec 2005)