Environmental Engineering 454
Treatment
—Waste that cannot be recycled should be treated to reduce its hazard.
Disposal
—Waste that is not treated should be disposed of in an environmentally safe manner.
Biomimicry
"replicating nature" Mimicking natural methods of manufacture of chemical compounds to create new ones Imitating mechanisms found in nature (for example, Velcro is like barbs on weed seed) Studying organizational principles from social behaviorof organisms, such as the flocking behaviorof birds or the emergent behaviorof bees and ants
National Implementation and enforcement of OHS
Chief Safety Officer and Inspectors are responsible for monitoring compliance with the OHS Act Have the power to shut down any enterprise for noncompliance Have the power to institute criminal charges against any employer or employee
End of Life Handling
DESIGN FOR DIS-ASSEMBLY (DfD) -developing the assemblies, components, materials, assembly or construction techniques, and information and management systems to accomplish this goal. recovery of materials maximizes economic value and minimizes environmental impacts through reuse, repair, remanufacture, and recycling. last resort -energy recovery from materials and safe biodegradation. DfDenables flexibility, convertibility, upgradability, and expandability supporting efforts to avoid the disposal of products or removal of buildings.
'Contaminants of Emerging Concern'
EDCs (endocrine disrupting compounds) hormones pharmaceuticals
Properties of LD50 and LC50
LD50and LC50 vary significantly with exposure time LD50and LC50 very specific to species tested Very difficult to extrapolate to other species Need to consider MOST SUSCEPTIBLE SPECIES Toxicity of combined contaminants significantly greater than toxicity of individual contaminants
Life Cycle Analysis
One of the most powerful tools (currently) available for sustainable development, Green Engineering etc Considers the total impact of the service/product over it's entire life ("Cradle to Grave") When the LCA of a product or service is assessed, the total picture (effect on environment, sustainability) maychange ... polystyrene cups vs glass cups brown paper bags vs plastic bags solar power vs fossil fuels **draw diagram
Implementing OHS in Workplace
Safety Policy ▪ cornerstone of OHS practice e.g. ▪ Vision ▪ Goals ▪ Commitments ▪ How these will be achieved **know diagram CEO (takes on full responsibilities of the Employer) ▪ may delegate to one or more "16.2 appointees" Safety Representatives -1 for every 100 employees (office), 1 for every 50 employees (industry) Safety Committee/s -one or more safety committees composed of safety representatives
Raw Water Contaminants
Suspended particles -occur generally in surface water and give water a turbid or murky appearance. Includes clay particles, algae, microorganisms, decaying plant material and other organic and inorganic substances. Colloidalparticles -extremely small suspended particles. Dissolved inorganic substances -normally do not affect the appearance of the water, but may cause the water to have a brackish or salty taste. Some dissolved substances may also cause the water to be toxic at very low concentrations e.g. arsenic and mercury. (major species -calcium, magnesium, chloride, fluoride, iron, manganese, nitrate, sulphur) Dissolved organic substances -generally present in most surface waters. Most dissolved organic substances are harmless, e.g. dissolved substances (called humicacids) from decaying plant matter. However, there may also be harmful organic substances in water, such as pesticides and herbicides that find their way into water sources. Micro-organisms -including bacteria, viruses and other organisms. Most are harmless, but disease-causing organisms (called pathogens) may enter water sources as a result of pollution by human and animal wastes and by untreated or poorly treated waste waters discharged into the water source. Water
Challenges facing DPR
Water quality ▪ EDCs, micro-organics, e.g. hormones, pharmaceuticals Public perception ▪ how was this handled in Singapore ? ▪ how was this handled in Windhoek ?
Anaerobic digestors
biodegradation with out oxygen complex, slow reaction: ▪ organics (in solids or liquid) ---> fatty acids ▪ fatty acids ---> acetic acid/acetone ▪ acetic acid ---> methane (g) ▪ overall: organics ---> methane + energy + some biomass each step accomplished by different species of bacteria rate limiting:-methanogenesis requires very careful control of temperature (usually 37oC), pH etc widely applied in industrial effluent treatment (particulate as well as dissolved organics) methane can be used to run a turbine -generate electricity receiving a lot of attention as an alternative source of energy
disinfection dangers
chlorine -can form trihalomethanes(THMs) -carcinogenic ozone -can break down compounds into smaller compounds which may be more toxic than the original
Why do we need an EMS?
helps the organisation to manage and improve its environmental performance help the business to comply with environmental laws and regulations. can generate financial savings through efficient practices (e.g. cutting waste and energy use) will improve the standing and reputation of the business with staff, client companies, partner organisations and wider stakeholders
membrane systems disadvantages
high energy costs because of high operating pressures (?) FOULING !!! -contaminants collect on membrane and reduce the flux
Steps in Water Treatment
identify the contaminants implement suitable removal/reduction processes ---- -clarification processes that are used to remove suspended material from water. These processes include coagulation, flocculation, sedimentation, flotation, filtration -disinfection processes including chemical treatment with chlorine and chlorine compounds, and advanced processes such as the use of ozone as well as physical processes such as ultra violet irradiation -advanced/specialised processes for the removal of dissolved inorganic substances including reverse osmosis, ion exchange and electrodialysis. -advanced oxidation processes are also used for the removal of dissolved organic substances, e.g. activated carbon **look at diagram
coagulation -common coagulants
inorganic metallic coagulants -aluminum sulphate, ferric sulphate, ferric chloride, aluminum chloride, sodium aluminate metal salts (hydrolysed) -polyaluminumchloride (PAC), polyaluminumsulphate(PAS) organic polymers -cationic, anionin, nonionic natural coagulants ?
Advanced oxidation processes
objective -break down "resilient" organics and micro-organics ozonation(O3) ▪ need sufficient high dose to completely oxidise organics, else smaller and more toxic compounds may be formed ozonationin combination with activated carbon (O3/BAC) ▪ ozone breaks the organics down into simpler compounds which are then biologically degraded by bacteria on the activated carbon peroxide/UV ▪ UV catalyses the formation of radicals which are powerful oxidants TiO2 ???
disinfection
objective -deactivate biological species that could be pathogenic ▪ primary disinfection -kill all pathogens that are in the water ▪ secondary disinfection -provide a residualto kill pathogens that are in the distribution network disinfectants :-oxidising agents (Clor O3), heavy metals (Ag or Cu), physical agents (heat or UV) important design parameter: [ C x t] ▪ concentrationof disinfectant and timeof exposure ▪ need high concentration for a short time, or low concentration for a longer time
aerobic digestor
objective: biologically converts organic material into energy, gases and biomass CAS consists of two vessels - ▪ biological reactor (aerated vessel) ---▪ receives liquid containing dissolved organics, ammonia etc from primary clarifier ---▪ aerated via air diffusers or aerator-mixers, to maintain DO > 2 mg/L ---▪ bacteria consume organics and form more bacteria ▪ settling tank ---▪ biomass settles out ---▪ overflow (very little dissolved organics) sent to disinfection step ---▪ underflow (sludge) split into two streams ---▪ returned activated sludge (RAS) -"hungry" bacteria used to seed reactor ---▪ waste activated sludge (WAS) excess sludge sent to sludge treatment plant
OHS Act of 1993
provides for the safety and health of persons at work and in connection with the use of plant and machinery. It further provides for the protection of people other than people at work from hazards arising out of or in connection with the activities from people at work. a pro-activeattempt to prevent and avoid work related injuries and illness regulates and control health and safety in all organisations, from a normal office environment to more hazardous environments like industrial plants and construction sites. Excludes -mine, or mining areas, ships, fishing boats and floating cranes Dangers in the workplace must be addressed by communication and cooperation between the workers and the employer. The workers and the employer must share the responsibility for health and safety in the workplace. Both parties must pro-activelyidentify dangers and develop control measures to make the workplace safe. The employer and the workers should set up a system where health and safety representatives inspect the workplace regularly and then report to a health and safety committee, who in turn may submit recommendations to the employer.
membrane systems advantages
very high and consistent product quality, without any chemical addition (or minimal chemical addition) product quality independent of feed quality product quality independent of skills of operator small footprint modular (can be easily expanded) very wide range of commercial membranes that can suit almost any application
Duties of the Employer under OHS
"Every employer shall provide and maintain, as far as is reasonably practicable, a working environment that is safe and without risk to the health and safety of his employees". ensure that the workplace is free of hazardous chemicals, micro organisms, articles, equipment, processes, etc. that may cause injury, damage or disease. where this is not possible, inform workers of these dangers, how they may be prevented, and how to work safely, and provide other protective measures for a safe workplace. identify potential hazards which may be present while work is being done, something is being produced, processed, used, stored or transported, and any equipment is being used establish the precautionary measures that are necessary to protect workers against the identified hazards and provide the means to implement these precautionary measures provide the necessary information, instructions, training and supervision while keeping the extent of workers' competence in mind. In other words, what they may do and may not do not permit anyone to carry on with any task unless the necessary precautionary measures have been taken take steps to ensure that every person under his or her control complies with the requirements of the Act enforce the necessary control measures in the interest of health and safety see to it that the work being done and the equipment used, is under the general supervision of a worker who has been trained to understand the hazards associated with the work such a worker must ensure that the precautionary measures are implemented and maintained. employees on health and safety hazards of any work being done, anything being produced, processed, used, stored, handled or transported, and any equipment or machinery being used. employees on information about precautionary measures against these hazards. the Health and Safety representatives of the occurrence of an incident in the workplace. An incident is an event that occurs at the workplace where ▪ a person is killed, injured or becomes ill. ▪ the spillage of a hazardous chemical substance ▪ where machinery runs out of control, without killing or injuring
Objective of Drinking Water Treatment
"reduce all constituents of water that are either dangerous or aesthetically unacceptable down to acceptable levels"
LD50
(delibrate) dose that causes death in 50 % of test subjects
Environment Management Plan (ISO 14001-2015) Steps
-It is a document detailing, at the highest management level, the environmental policies of a company and the appropriate procedures for its implementation. It is one of the requirements for ISO 14000 certification and other environment programs Plan --> Do --> Check --> Act -Initial Prepatory Review -Environmental Policy -Register of environmental Aspects and Environmental Legislation -management program, objectives and targets -operating procedures -environmental management manual -internal environmental auditing -management review -continuous improvement
Millennium Development Goals
-agenda for reducing poverty and improving lives based on what leaders agreed on at the Millennium summit in 2000 --eradicate extreme poverty and hunger --achieve universal primary education --promote gender equality and empower women --reduce child mortality --improve maternal health --combat AID/HIV, malaria, and other diseases --ensure environmental sustainability -integrate principals of sustainable development into country policies and programs and reverse the loss of environmental resources -reduce by half the proportion of people without access to safe drinking water -achieve significant improvement in the lives of at least 100 slum dwellers --develop a global partnership for development
SDGS relevant to environmental engineers
-clean water and sanitation -affordable and clean energy -sustainable cities and communities -responsible consumption and production -climate action -life below water -life on land
Barriers to DPR
-cost -public perception
Pollution Prevention
-creating, handling, storing, and disposing of waste does not add value to the product or service. -the traditional mechanisms for managing wastes often move wastes from one medium, such as water, to another, such as a landfill. -WASTE COSTS MONEY, TIME, ENERGY and MATERIALS therefore: PP: increasing the efficiency of a process to reduce the amount of pollution generated. Incrementalistapproach -"eco-efficiency", where the current system is tweaked to be better than before. Source Reduction >> recycling >> treatment >> disposal
Alternatives to DPR
-desalinization
coagulation mechanisms
-electric double layer compressor -charge neutralization -inter-particle bridging -precipitation and enmeshment
LEED: Leadership in Environmental Energy & Design
-given to structures that are designed, built, and operated in a sustainable way -examples that meet criteria include: -green roofs -using structure mass to reduce energy demand -minimized materials used to build structure -storage of water/water collection -minimize materials/reuse wastes
Stages in a project
-identification of a need -conceptual approach -design -testing -planning -production/implementation
Approaches to solving a problem
-improve the existing system (incremental) immediate to short term solution to problem -re-engineer the existing system -redefine the problem (holistic view) long term more sustainable solution
Drivers for Water reuse
-increasing population, industrialization, urbanization (demand goes up but water supply remains constant -increasing contamination of fresh water sources -unplanned development -unregulated industries -water scarce regions - very little rainfall -alternatively, rainfall is not in a catchment zone -Climate change -decrease in local rainfall -major variations in seasonal rainfall -significant changes in summer/winter temperatures, increasing evaporation during the "dry season" -development from environment protection -wastewater/effluents have to be partially treated before discharge to the environment -further-the treated wastewater/effluent may be of a higher quality than the river -it would make sense to go the whole way and treat the water to reuse standards
Development Limits
-natural resources -societal needs & capacity -techno-economic capabilities
New Approaches to Domestic wastewater management
-urine diversion toilets -Gates Foundation "Reinvent the toilet" project
reverse osmosis pressure requirement
30-60-alot Why? • to overcome osmotic pressure of the concentrate (Δπ) • for seawater: Δπ ~ 20 to 30 bar !!! • true driving force = ΔP -Δπ
Risk Assessment
4 steps: Hazard Identification Dose-Response Assessment Exposure Assessment Risk Characterization
Conventional vs. Bioreactor membrane
Advantages over CAS: MLSS not limited by settling characteristics -can operate between 12g/L and 20 g/L • higher volumetric throughput for given reactor volume • small reactor volume required for specified volumetric throughput final product is completely free of SS and bacteria (disinfected) small footprint (reduced reactor volume, no external clarifier, no sludge thickener) substantially reduced sludge production (CAS = 0,6 kg sludge/kg BOD, IMBR = 0,03 kg sludge/kg BOD) enhanced removal of organics ? (more varied biomass population) -very little operator input required very little maintenance required (membrane cleaning every 6 to 12 months) -can be retrofitted to existing AS plants Disadvantages: requires high aeration rates (energy) membranes require chemical cleaning periodically (6 to 12 months) Economics ???
Toxicology
Affected by: form and activity of the chemical dosage / concentration exposure routes and duration species ability to be absorbed metabolism excretion presence of other chemicals Unfortunately, needs to be established by empirical studies ... Dose -response curves ... / concentration-response curves ...**know the diagram toxicity is a function of both dose and time ... acutetoxicity -causes death in hours/days chronictoxicity -causes death over weeks/months/years
What is sustainable development? Give an example.
Bruntland: "Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs." "development that does not exceed the limits of the ecological system within which it takes place." Continue the positive outputs, while minimising and reversing the negative effects -minimise production and emission of waste -maximise efficient utilisation of existing nonrenewable resources -increase usage of renewable resources -devise approaches to deal with new challenges that result from environmental stresses Whilst sustainabilitymay have previously been defined solely in terms of economics, it is now being redefined to include the impact on Society and the Environment, and on the availability of natural resources Example: Shanghai Tower: daylighting through windows, green landscaping for cooling, double facade, wind turbines in the facade.
SDG: Sustainable Cities and Communities
Challenges: 1 billion people continue to live in slums. Urgent action is needed to reverse the current situation, which sees the vast majority of urban residents breathing poor-quality air and having limited access to transport and open public spaces. With the areas occupied by cities growing faster than their populations, there are profound repercussions for sustainability.
SDG: Life below water
Challenges: The expansion of protected areas for marine biodiversity and existing policies and treaties that encourage responsible use of ocean resources are still insufficient to combat the adverse effects of overfishing, growing ocean acidification due to climate change and worsening coastal eutrophication. Solutions: As billions of people depend on oceans for their livelihood and food source and on the transboundary nature of oceans, increased efforts and interventions are needed to conserve and sustainably use ocean resources at all levels.
SDG: responsible consumption and production
Challenges: Worldwide material consumption has expanded rapidly, as has material footprint per capita, seriously jeopardizing the achievement of Sustainable Development Goal 12 and the Goals more broadly. Urgent action is needed to ensure that current material needs do not lead to the overextraction of resources or to the degradation of environmental resources, Solutions: policies that improve resource efficiency, reduce waste and mainstream sustainability practices across all sectors of the economy.
SDG: Clean water and sanitation
Challenges: achieving universal access to even basic sanitation service by 2030 would require doubling the current annual rate of progress. More efficient use and management of water are critical to addressing the growing demand for water, threats to water security and the increasing frequency and severity of droughts and floods resulting from climate change. Solution: Implement integrated water resources management:
SDG: Climate Action
Challenges: far more ambitious plans and accelerated action are needed on mitigation and adaptation. Solutions: Access to finance and strengthened capacities need to be scaled up at a much faster rate, particularly for least developed countries and small island developing States.
SDG: Affordable and Clean Energy
Challenges: some 800 million people remain without electricity while access to clean cooking fuels and technologies needs dedicated attention. In addition, if Sustainable Development Goals 7, 13 and related Goals are to be met, much higher levels of ambition are required with regard to renewable energy, including transportation and heating.
SDG: Life on Land
Challenges: the 2020 targets of Sustainable Development Goal 15 are unlikely to be met, land degradation continues, biodiversity loss is occurring at an alarming rate, and invasive species and the illicit poaching and trafficking of wildlife continue to thwart efforts to protect and restore vital ecosystems and species. Solutions: Protecting important sites for terrestrial and freshwater biodiversity is vital for ensuring long-term and sustainable use of terrestrial and freshwater natural resources.
GE Principle 8
Design for an unnecessary capacity or capability solutions should be considered a design flaw one size fits all = bad, extra size means wasted materials Example: real time process analysis and controlled systems rather that overchlorinating or disinfecting domestic drinkign water, ship by rail with railcars that can attach or detach as needed rather than shipping with underutilized fixed capacity vehicles
GE Principle 10
Design of products, processes, and systems must include integration and interconnectivity with available energy and material flows Make use of what you've got available Example: instead of flaring at refineries use co generation of energy, use regenerative braking and electronic cars
GE Principle 1
Designers need to strive to ensure that all material and energy inputs and outputs are as inherently nonhazardous as possible In implementing this principle this requires the engineer to consider the selected material and energy inputs and outputs to ascertain the hazardousness of each and evaluate whether there maybe a less harmful option which still meets the needs of the client and project. Example: In water and wastewater treatment industries the hazardous inputs and outputs are created from adding chemcials to treat the water, and choices of chemicals is driven by cost rather than considering hazardous nature of them. Usually cheaper to transport concentrated chemicals which are inherently more hazardous
Checking Phase EMS
EMS Audit --> Monitoring & measuring --> non-conformance and corrective/preventative action --> records ---> EMS audit
GE Principle 6
Embedded entropy and complexity must be viewed as an investment when making design choices on recycle, reuse, or beneficial disposition More focused on products than processes. Less complicated products can more easily be recycled. If a product is complex then it should be designed to be reused IBM PC's used to be made with 15 different types of screws (unnecessary complexity) Replaced with 1 type of screw Easier to disassemble & recycle
Exposure Assessment
How much of the pollutant are people exposed to during a specific time period? How many people are exposed? "The process of measuring or estimating the magnitude, frequency, and duration of human exposure to an agent in the environment, or estimating future exposures for an agent that has not yet been released. An exposure assessment includes some discussion of the size, nature, and types of human populations exposed to the agent, as well as discussion of the uncertainties in the above information. Exposure can be measured directly, but more commonly is estimated indirectly through consideration of measured concentrations in the environment, consideration of models of chemical transport and fate in the environment, and estimates of human intake over time."
Workplace Risk
In industry, employees are exposed to work-specific hazards: hazardous chemicals, high temperatures, high pressures working machinery on-site hazards in construction sites
Integration
Integration of local material and energy flows (e.g. eco-industrial park, Kalundborg, Denmark) Four industrial facilities—a power plant, an oil refinery, a plaster-board manufacturing plant, and a biotechnology production facility—and the local municipality participate in the Kalundborg symbiosis.
GE Principle 2
It is better to prevent waste than to treat or clean up waste after it is formed Engineers are often asked to design solutions to treat the waste once created, whereas this principle states that review should be held to ascertain if source reduction can be achieved. Example: Tremendous $$ spent on waste treatment, disposal and remediation; in the past not always considered in cost of plant - full cost accounting (life cycle analysis). Simple (no/low cost) solutions: sloping piping downwards to cut wash solvent use; short, fat pipes reduces drag, lower energy use; paint storage tanks white; no dead-end sample points
Define Ecological Deficit/reserve
It occurs when the Ecological Footprint of a population is higher than the biocapacity of the area available to a population. A national level this means that a nation is importing biocapacity through trade, liquidating national ecological assets, or emitting carbon dioxide waste into the atmosphere. Ecological Reserve is when the biocapacity exceeds a regions Ecological Footprint
GE Principle 12
Material and energy inputs should be renewable rather than depleting Don't want to deplete our natural resources Need resources to be there for future generations Examples: Energy: solar, wind, hydroelectric, geothermal, biomass, hydrogen (fuel cells)
GE Principle 9
Material diversity in multi-component products should be minimized to promote disassembly and value retention Examples: •Automobile design: use single materials rather than alloys (metal and polymeric) •Additives; create multi-functional additives rather than packages, incorporate additive functionality into polymeric backbone (dyes, flame retardants) •Pigments; can pigments be switched "on" and "off"; can changes in pigment physical properties allow for variety of colors?
Municipal wastewater treatment
Objective: Reduce contaminants in wastewater streams to acceptable levels before discharge into water bodies
GE Principle 5
Products, processes, and systems should be "output pulled" rather than "input pushed" through the use of energy and materials Example: Grocery stores use RFID to track sales and supplies of chilled food
GE Principle 11
Products, processes, and systems should be designed for performance in a commercial "afterlife" Example: •Conversion of old factories to housing •Disassembly of equipment for reuse of components •Creation of "plastic lumber" from used polymeric packaging material (molecular reuse)
GE Principle 4
Products, processes, and systems should be designed to maximize mass, energy, space , and time efficiency. Example: digital media rather than print media, ecoindustrial park planning rather than urban sprawl,
GE Principle 3
Separation and purification operations should be designed to minimize energy consumption and materials use Example: rather than permanently joining two materials, making them able to be reversibly fastened. Rather than intensive separating of recycled municipal waste, use local/residential material and energy systems. Recycling of PET bottles: selfseparation of products using intrinsic physical/chemical properties
Doing Phase EMS
Structure & Responsibility --> training, awareness, and competence --> communication --> documentation --> EMS Documentation -->document control --> operational control --> emergency preparedness and response
GE Principle 7
Targeted durability, not immortality, should be a design goal Example: CFCS, non-flammable, non toxic, inexpensive, but too stable and they migrate to the upper atmosphere and contribute to ozone depletion
Define and Explain Green Engineering
The design, discovery and implementation of engineering solutions with an awareness of potential benefits and problems in terms of the environment, the economy and the society throughout the lifetime of the design. It considers both technical and non-technical approaches and issues -necessitates engineering solutions that are innovative and creative. -puts into perspective, and prioritises, sustainability.
Why are we running into a water problem?
Total water: -97% saline -3% fresh Of Fresh: -68.7% glacier -30.1% ground water -.3% surface water Of Surface Fresh: -87% lakes -2% rivers
Economic Indicators for change
Traditional -Median income per capita income relative to the U.S. average - unemployment rate number of companies number of jobs -size of economy as measured by GDP and GNP Sustainable: -number of hours of paid employment at the average wage required to support basic needs -diversity and vitality of local job base, number and variability in size of companies, number and variablity of industry types, variability in skill levels required for jobs -wages paid in the local economy that are spent in the local economy, Dollars spent in the local economy which pay for local labor and local natural resources, percent of local economy based on renewable local resources
Social Indicators for Change
Traditional: -SAT and other standardized tests scores -number of registered voters Sustainable: -number of students trained for jobs that are in the local economy, number of students who go to college and come back to the community -number of voters who vote in elections, number of voters who attend town meetings
Environmental Indicators for Change
Traditional: -ambient levels of pollution in air and water -tons of solid waste generated -costs of fuel Sustainable: -use and generation of toxic materials, vehicle miles traveled -percent of products produced which are durable, repairable, or readily recyclable or compostable -total energy used from all sources, Ratio of renewable energy used at renewable rate compared to nonrenewable energy
Source reduction
Waste (hazardous substance, pollutant, or contaminants) should be prevented at the source (prior to recycling, treatment, or disposal
Recycling
Waste generated should be reused either in the process that created it or in another process.
Dose-Response Assessment
What are the health problems at different exposures? "A dose-response relationship describes how the likelihood and severity of adverse health effects (the responses) are related to the amount and condition of exposure to an agent (the dose provided). The same principles generally apply for studies where the exposure is to a concentration of the agent. Typically, as the dose increases, the measured response also increases. At low doses there may be no response. At some level of dose the responses begin to occur in a small fraction of the study population or at a low probability rate. Both the dose at which response begin to appear and the rate at which it increases given increasing dose can be variable between different pollutants, individuals, exposure routes, etc.
Hazard Identification
What health problems are caused by pollutants? Hazard Identification is the process of determining whether exposure to a stressor can cause an increase in the incidence of specific adverse health effects (e.g., cancer, birth defects). It is also whether the adverse health effect is likely to occur in humans.
Risk Characterization
What is the extra risk of health problems in the exposed population? A risk characterization conveys the risk assessor's judgment as to the nature and presence or absence of risks, along with information about how the risk was assessed, where assumptions and uncertainties still exist, and where policy choices will need to be made. Risk characterization takes place in both human health risk assessments and ecological risk assessments In practice, each component of the risk assessment (e.g. hazard assessment, dose-response assessment, exposure assessment) has an individual risk characterization written to carry forward the key findings, assumptions, limitations, and uncertainties. The set of these individual risk characterizations provide the information basis to write an integrative risk characterization analysis. The final, overall risk characterization thus consists of the individual risk characterizations plus an integrative analysis.
Define Ecological Footprint
a determination of the biologically productive land area required to provide an individual's resource supplies and absorb the wastes their activities produce, ie. the amount of nature needed for an individual to occupy and keep intact their daily lifestyle, measures how much demand human consumption places on the biosphere. measured in global hectares. It is derived by tracking how much biologically productive area it takes to absorb a population's carbon dioxide emissions and to generate all the resources it consumes. Consumption is calculated by adding all imports and subtracting exports from national production. It uses yields of primary products (cropland, forest, grazing land) to calculate how much area necessary to support a given activity
Membrane definition
a selective barrier that allows some species to pass through easily, whilst restricting the passage of other species
Environmental Management System
a structured framework for managing an organisation's significant impacts on the environment Significant impacts: -all the ways in which the business impacts on the environment -waste generation, water and energy use, gaseous emissions, transport, consumption of raw materials, use of hazardous raw materials or production of hazardous wastes, space utilised, impacts on wildlife (biodiversity).
Water Quality Standards
acceptable levels of contaminants based on toxicology data and human perceptions
Sustainable Development Goals
aka. 2030 agenda: will mobilize efforts to end all forms of poverty, fight inequalities and tackle climate change, while ensuring that no one is left behind. -are unique in that they call for action by all countries, poor, rich and middle-income to promote prosperity while protecting the planet. They recognize that ending poverty must go hand-in-hand with strategies that build economic growth and addresses a range of social needs including education, health, social protection, and job opportunities, while tackling climate change and environmental protection. -no poverty -zero hunger -good health and well-being -quality education -gender equality -clean water and sanitation -affordable and clean energy -decent work and economic growth -industry, innovation, and infrastructure -reduced inequalities -sustainable cities and communities -responsible consumption and production -climate action -life below water -life on land -peace, justice, and strong institutions -partnerships for the goals
Hazard
anything that can cause harm
Environmental toxicology
deals with the effects of chemicals on living organisms. ▪ an impact on one level will be reflected in other levels as well. ▪ e.g. there is evidence that elevated PCB levels in fish results in adverse health effects to children born from mothers who included fish in their diet.
Define and Explain the Tragedy of the Commons
defined as an economic theory that describes how people often use natural resources to their advantage without considering the good of a group or society as a whole. When a number of individuals consider only their own welfare in its manner, it leads to negative outcomes for everybody , as the natural resources become depleted. Example: the extinction of the dodo bird, native to only a few islands this flightless bird provided easy meat for sailors traveling the southern Indian Ocean. Due to over hunting the Dodo was driven to extinction less than a century after its discovery.
Design for the Environment
design approach in which environmental burdens are intentionally considered and eliminated where possible at the design phase. stategies include: -source reduction -material recovery -use of treatable as opposed to untreatable materials
Three pillars or Triple Bottom Line Principle
development must: -meet a society need -be viable and sustainable from a point of view of economics -be sustainable in terms of the environment
Planning Phase EMS
environmental aspects + legal and other requirements --> objectives & targets --> environmental program
LC50
environmental concentration that causes death in 50 % of test subjects
"Natural wastewater technologies"
freshwater sources --> usage --> waste water (rivers, lakes, sea, ground) --> evaporation --> water vapor in atmosphere
Risk
likelihood (probability) of injury, disease, or death there are innumerable sources of risk ... Risk = f[hazard, exposure]
Risk Perception
peoples assessment of potential hazards/risks UNDERESTIMATIONof real risk, usually based on : familiarity with the risk voluntary involvement with the risk perceived positive value of the risk lack of knowledge of the hazard ▪ e.g. crime levels, smoking, cellphones, driving at speed OVERESTIMATIONof the risk usually based on: involuntary involvement lack of knowledge of the hazard ▪ e.g. recycling of wastewater for potable use
Industrial Ecology
shift process from "linear" to "closed loop"
Duties of Employee
take care of his or her own health and safety, as well as that of other people who may be affected by his or her actions or negligence to act. co-operate with the employer where the Act imposes a duty or requirements on the worker carry out any lawful instruction which the employer or authorised person prescribes with regard to health and safety comply with the rules and procedures that the employer gives him/her wear the prescribed safety clothing or use the prescribed safety equipment where it is required report unsafe or unhealthy conditions to the employer or health and safety representative as soon as possible if he or she is involved in an incident that may influence his or her health or cause an injury, report that incident to the employer, and authorised person or the health and safety representative as soon as possible, but no later than by the end of the shift.
Define Biological Capacity
the area of productive land available to produce resources or absorb wastes for an individual given current management practices. Measures in standard units called global hectares
Design stage
the engineering stage where the greatest influence can be achieved in terms of sustainable outcomes. Represents the time for innovation, brainstorming, and creativity, offering an occasion to integrate sustainability goals into the specifications of the product, process, or system. sustainability goals can be incorporated into design evaluation as a minimum standard for bringing the design to production or implementation. Fundamental
Environmental Risk
the risk resulting from exposure to a potential environmental hazard : specific chemicals chemical mixtures such as secondhandsmoke and automobile exhaust pathogens stratospheric ozone depletion climate change scarcity of safe water applies to the health of plants, animals, and entire ecosystems, which support human livelihood and enhance our quality of life. We will focus on environmental risk to Humansderived from exposure to chemicals or substances.
Exposure
time or frequency for which you are exposed to the hazard effects include: -death, disease, birth defect, infertility, stunted growth, neurological disorder etc. paths: ingestion, inhalation, or skin contact. drinking water, eating food, ingesting soil and dust, inhaling airborne contaminants that could be in a vapour or particulate form, and contacting chemicals that are transported through the skin.
direct potable water reuse
▪ No intermediate water body ▪ treated wastewater from wastewater treatment plant goes directly into potable water treatment plant ▪ need/applicability ▪ no suitable water body available as an intermediate ▪ treated wastewater is of higher quality than the water body
Carcinogens
▪ concentration of a chemical builds up in an organism/species over time/trophic levels ▪ e.g. PCBs may have had no direct adverse effect on adult fish but there is an impact on some fish offspring and the next trophic level (humans). Toxic effects -carcinogenicand non-carcinogenic. ▪ carcinogenpromotes or induces tumors(cancer) ▪ primary carcinogens directly initiate cancer ▪ pro-carcinogensare not carcinogens but are metabolized to form carcinogens and thus indirectly initiate cancer ▪ co-carcinogensare not carcinogens but enhance the carcinogenicity of other chemicals ▪ promotersenhance the growth of cancer cells.
Palatable Water
▪ free of turbidity ("cloudiness") ▪ free of odours and tastes ▪ free of colour palatable does not equal safe
Endocrine Disruptors
▪ mimic the effect of hormones ▪ sources and typical compounds...
Modification to CAS
▪ nitrification: NH4- + 2O2 ---> NO3- + 2H+ + H2O (requires oxygen) ▪ denitrification: (carbohydrate) + NO3- ---> N2 + H20 + CO2 + NH3 (inhibited by oxygen) ▪removal of phosphorous: In the anaerobic compartment phosphorus is removed by converting it from dissolved phosphate to particulate phosphorus stored in biological cells, removed in secondary clarifier
indirect potable water reuse
▪ treated wastewater goes into an ENVIRONMENTAL BARRIER (river, lake, ground) ▪ water extracted from river/lake/ground and treated to potable standards
Potable Water
▪ water that is safe for consumption ▪ free of harmful micro-organisms ▪ free of harmful chemicals