Lecture 9 - 2024 Pollution & Remediation PDF

Part 1. Pollution in the Energy Sector: Hydraulic Fracking and Wind Turbines Part 2. Remediation & Moving Forward  Wind Turbines Large towers with rotating blades that use wind to generate electricity: – Video: https://www.youtube.com/watch?v=tsZITSeQFR0 While overall...

Part 1. Pollution in the Energy Sector: Hydraulic Fracking and Wind Turbines Part 2. Remediation & Moving Forward  Wind Turbines Large towers with rotating blades that use wind to generate electricity: – Video: https://www.youtube.com/watch?v=tsZITSeQFR0 While overall support for wind energy in Ontario is high (~89%), local opposition is strong – Has lead to legal appeals and lawsuits due to a number of reported health concerns and symptoms Source: Council of Canadian Academies, 2015  Wind Energy in Canada 6% of Canada’s electricity demand, generating enough power to meet the needs of over three million Canadian homes. There are 299 wind farms operating from coast to coast, including projects in two of the three northern territories.  Noise and Sound Noise refers to unwanted or unwelcomed sound that produces annoyance or physiological stress – If loud enough and sustained, can cause hearing damage – Associated with community annoyance and sleep disturbances Sound is energy is the form of airborne vibrations or pressure waves (AKA sound waves) – Frequency of sound refers to number of complete sound waves the source produces in a single second (i.e. Hertz, Hz) Frequencies below 20Hz categorized as infrasound, and between 20-200 Hz as low frequency noise – Sound is felt as pressure (loudness), reported as decibels (dB) Wind turbines cause noise by movement of mechanical parts and displacement of air by the moving blades  Wind Turbine Setback Distances Provincial setback distances for wind turbines were established in Ontario to protect public health and safety from noise and structural hazards The setbacks are based on modelling of sound produced by wind turbines and are intended to limit sound at the nearest residence to no more than 40 dB The minimum setback is 550 meters from a receptor Setback distances increase with increasing numbers of turbines and their sound level – E.g. a project with five turbines, each with a sound power level of 107 dB, must have its turbines setback at least 950 metres from the nearest receptor  Wind Turbine Health Study In 2013, Health Canada/Statistics Canada conducted the “Wind Turbine Noise and Health Study” – In-person survey of randomly-selected households a varying distances from wind farms in ON and PEI – Objectively measured outcomes included hair cortisol levels, blood pressure and sleep quality – >4000 hrs of wind turbine noise measurements to assess A-weighted noise levels (dBA), low frequency noise (dBC), and infrasound Overall response rate of 79% (1238/1570 homes participated)  Wind Turbine Health Study The following self-reported health outcomes were measured: – Sleep disturbance (e.g., general disturbance, use of sleep medication, diagnosed sleep disorders) – Illnesses (e.g. dizziness, tinnitus, migraines, headaches) and chronic health conditions (e.g. heart disease, diabetes) – Perceived stress – Overall quality-of-life – Annoyance The only measure associated with increasing levels of wind turbine noise was annoyance, at sound levels >35 dB Similar to other studies, annoyance also modified by other factors (e.g. visual perception, beliefs about intrusiveness, and a lack of direct economic benefit)  Electromagnetic Energy The electromagnetic energy spectrum covers a wide range of radiation frequencies Ionizing radiation is comparatively high in energy and can change atoms into “ions” (charged particles) by removing electrons. "Non-ionizing" radiation, including RF, is comparatively lower in energy but can cause molecules to vibrate. RF radiation is emitted from a variety of common wireless communication devices, including cell phones, cordless (DECT) phones, Wi-Fi computer networks, smart meters, and baby monitors. X-rays, visible light, microwaves, radio waves, and EMF are all forms of electromagnetic energy.  Electromagnetic Radiation A number of symptoms such as itchy skin, insomnia, fatigue, headaches, vertigo, and nausea have been reported by people exposed to electromagnetic radiation. Although some population surveys have linked increased reports of symptoms with greater use of cell phones, a nocebo effect cannot be ruled out, and numerous laboratory studies have not shown a relationship between exposure to RF and the appearance of acute symptoms during or shortly after exposure. Studies examining longer time frames may better identify the relationship between RF exposure and reported symptoms Nocebo effect: A detrimental effect on health produced by psychological or psychosomatic factors such as negative expectations of exposure  Electromagnetic Fields (EMF) EMF around wind farms can come from grid connection lines, turbine generators, electrical transformers, and underground network cables International Agency for Research on Cancer (IARC) categorizes EMF as a Class 2B “possible human carcinogen” Consistent with previous studies, a recent study in Ontario found EMF levels from wind turbines are negligible compared to common household exposures Wind Turbines: Causal Model Source: Council of Canadian Academies, 2015  Other Health/Safety Concerns Shadow flicker – Occurs when blades of a wind turbine rotate in sunny conditions, casting moving shadows on the ground – One study found association with annoyance; could also be a distraction hazard for drivers Ice throw and ice shed – Ice can form on turbines, and can be thrown from moving blades – Could present physical hazards to nearby people Structural hazards – Structural collapse and/or blade failure could result in potentially fatal hazards for nearby people – Injuries and fatalities have been reported among workers (during construction and transportation) Map showing the vast potential of offshore wind worldwide (Source: Equinor)  Natural Gas Natural gas is fossil fuel containing mixture of hydrocarbons (e.g. methane, ethane, propane) and can contain other impurities (e.g. Sulphur, CO2) Declining natural deposits of “conventional” natural gas leading to increased extraction of “unconventional” deposits – Conventional = extracted with single vertical well from porous and permeable geological formations – Unconventional = contained in layers in geological formations with low permeability, requiring specialized extraction process (including horizontal/s-shaped drilling and hydraulic fracturing, AKA “fracking”) Shale gas = unconventional gas, mostly composed of methane, and found in tiny layers of sedimentary rock 1-3 km below the earth’s surface (contains small amounts of other gases such as ethane, butane, pentane, nitrogen, helium, and carbon dioxide) Video: https://www.youtube.com/watch?v=VY34PQUiwOQ Source: Office of the Auditor General of Canada, 2012 Source: National Energy Board, 2009  Hydraulic Fracturing Fracking fluid consists of water combined with viscosity-reducing agent and “proppants” (e.g. crystalline silica, ceramic beads) to hold the newly created fractures open – Numerous other chemicals added to limit bacterial growth to prevent well casing corrosion and ensure effectiveness One-quarter of fluid returns to the surface (flowback), along with water in shale, which contains total dissolved solids, high saline content, and naturally occurring radioactive materials – Wastewater can be stored in surface ponds, treated, recycled, or disposed of via deep-well injection  Public Health Implications There are increasing public health concerns related to the extraction of shale gas Potential public health impacts are determined by: – Relative proximity of communities to extraction sites – Pathways of exposure, including: Drinking water Air quality Seismic activity Other impacts  Drinking Water Chemical and radiological contamination of drinking water sources could occur due to: – Spills of hydraulic fracturing fluids and produced water – Underground migration of liquids and gases (e.g. methane) – Well leaks (e.g. due to imperfections in well casing and degradation over time) – Inadequate treatment and discharge of wastewater The U.S. studies have shown higher levels of drinking water well contamination in homes located closer to shale gas production vs. those farther away  Air Quality Shale gas production can generate a variety of air pollutants: – Criteria air pollutants, crystalline silica, hydrogen sulphide (H2S), methane, CO2, and radon Can be due to point (e.g. stack), transportation (e.g. trucks), fugitive (e.g. leaks), or area sources (e.g. aggregate emissions) Each stage of production can lead to different pollutants During construction and operation, vehicle traffic can release diesel exhaust and PM During drilling and completion of wells, flowback fluids can emit air toxins (e.g. VOCs, methane, radon) – Gas portion is often vented or flared off  Air Quality During gas production, pressure and heat are used to separate the gas from produced water and liquid hydrocarbons – Produces VOCs and BTEX (Benzene, Toluene, Ethylbenzene, & Xylene) – Storage of water and hydrocarbons can cause “fugitive” emissions Air pollution depends on characteristics of shale gas and weather conditions Some US studies have shown potential for greater exposure to air pollutants near shale gas production sites, but overall evidence is still limited  Induced Seismic Activity Shale gas production routinely causes minor, injection- induced “micro-earthquakes” (magnitudes 75% of particles present Water treatment not 100% effective in removal Microplastics present in finished water Relatively low concentrations detected Unknown health risk (especially