Environmental Engineering for the 21st Century Addressing Grand Challenges (2019) / Chapter Skim
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Grand Challenge 3: Design a Future Without Pollution or Waste
Grand Challenge 3: Design a Future Without Pollution or Waste
Pages 44-53
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From page 44... ...
An analysis of five high-income countries found that one-half to three-quarters of annual resource inputs are returned to the environment as waste within a year.159 Despite improved efficiency in the use of resources, the overall production of waste in many countries, including the United States, continues to increase.160 The "take-make-dispose" model introduces large amounts of pollutants into the water, soil, and air. Throughout much of the 20th century, large-scale chemical production combined with inappropriate chemical handling and waste disposal created a daunting array of legacy hazardous waste sites globally.165 Technologies to characterize these sites and contain and remove hazardous contaminants have advanced significantly over the past three decades, and there have been many successes.166 However, there remain at least 126,000 hazardous waste sites with residual contamination in the United States alone, about 12,000 of which are considered unlikely to be remediated to the point of unrestricted use with current technology.
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From page 45... ...
343 676 1,293 2,080 573 619 774 912 Waste (kg/capita/year) 219 343 288 344 423 628 777 840 Country Income Group Lower Lower Middle Upper Middle High Income Income Income Income 2010 Projected 2025 Current and projected urban waste generation by income level and year.
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From page 46... ...
These include stakeholder engagement and sampling of public water supplies in the United States, up life-cycle analysis to identify the best long-term solutions to 15 million people live in areas where their drinking water that are socially acceptable and economically viable while exceeds the EPA health advisory level.185 However, in mid- minimizing negative side effects of cleanup activities, such 2018, the Agency for Toxic Substances and Disease Registry as air pollution and ecosystem degradation.191 stated in a draft toxicology risk assessment that the EPA level may be 7 to 10 times too high for two common PFAS compounds to protect against health risks.186 Continued research is needed to determine the scope of the problem, assess the risks posed by the many different chemicals, and develop water treatment options where appropriate to inform policy decisions for use and management of these compounds. Rapidly developing countries are also facing escalating environmental crises as a consequence of major economic growth without regard for socioenvironmental costs.
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From page 47... ...
are accumulating in the food chain with a largely unknown effect.180 Wastewater discharges, urban and agricultural runoff, and fossil fuel combustion sources have overloaded lakes, estuaries, and rivers with nutrients, fostering algal blooms that can deplete oxygen and produce toxins.181 All of these ecological problems ultimately harm human health and disrupt industries such as fisheries and agriculture. In 2014, for example, about 500,000 residents of Toledo, Ohio, were ordered not to use their tap water for days due to toxins produced by an algal bloom in Lake Erie.182 Design a Future Without Pollution or Waste | 47
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From page 48... ...
First, a new paradigm of waste management and pollution prevention is needed -- one that shifts from a linear model of resource extraction, production, use, disposal, and cleanup toward one designed to prevent waste and pollution from the outset. Second, innovative approaches are needed to recover valuable resources from the waste we do produce.
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From page 49... ...
Benefits of such an integrated approach include wise use of resources, improved human health, and enhanced protection of natural systems. Advances needed to support a circular economy include efficient and effective separation and recycling technologies and market forces or government incentives that recognize the broader impacts of pollution and waste (see Challenge 5)
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From page 50... ...
However, MTBE became a groundwater quality problem once gasoline leaked from underground storage tanks because MTBE was able to migrate farther and was more resistant to biodegradation than other compounds in gasoline.194 Of the more than 140,000 new chemicals that have been introduced since 1950, fewer than half have been subject to human safety or toxicity testing.195 EPA's Pollution Prevention Framework can be used to estimate physical properties, which are then used to predict environmental concerns such as toxicity, mobility, persistence, and bioaccumulation, but more development and validation is needed. In addition, there are significant needs related to risk communication to help the public and decision makers understand the true costs of pollution.
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From page 51... ...
. Many of today's municipal and agricultural waste streams are rich in organic carbon, which could be recovered and channeled toward chemical manufacturing or energy recovery.198 The amount of energy contained in wastewater is equivalent to several multiples of the amount of energy required to treat it.199 Energy recovery has been implemented at numerous centralized wastewater treatment plants, including in Oakland, California, and in Strass, Austria, by converting a fraction of the incoming organic carbon to biogas to produce heat and electricity.200 However, technologies have not yet been developed to cost-effectively capture the full potential of the embedded energy.201 Recovery of resources from waste streams has long been practiced, but in a nonsystematic fashion.
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From page 52... ...
What Environmental Engineers Can Do With training in environmental chemistry, microbiology, hydrology, transport processes, solid waste management, water and wastewater treatment, and air pollution -- as well as skills in life-cycle and systems thinking -- environmental engineers bring important capabilities toward designing a future without pollution 52 | ENVIRONMENTAL ENGINEERING IN THE 21st CENTURY: ADDRESSING GRAND CHALLENGES
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From page 53... ...
It is possible to design cookstoves that are much cleaner burning to benefit health, local environmental quality, and climate, but there are cultural, economic, and logistical hurdles to their adoption.213 Improving resource recovery in developed countries may require people to change their behaviors and accept new approaches to waste separation. An interdisciplinary approach applying social and cultural knowledge is crucial to overcoming such hurdles to guide the development and adoption of sustainable solutions.
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