Incident description and its Environmental Impact
Mount Polley Mine Spill comprised of a breach of the tailing pond that drained its contaminated water into the Quesnel Lake and the Cariboo River. Consistently, Quesnel Lake was among the largest lakes in the world with clean and deep water. However, after testing the purity of water in the lake, the results revealed that increased levels of arsenic, selenium among other metallic wastes had contaminated the water. The water from the tailing pond consisted slurry of toxic components that contaminated the lake waters as well as addition of mud in the lake. Pollutants spilled in the lake are among the biggest environmental disasters encountered in the Canadian history. Test results indicated that 326 tonnes of nickel, 18, 000 tonnes of copper, 176 tonnes of lead and over 350 tonnes of Arsenic were present in the contaminated water. Notably, the said hard metals have a great environmental impact that affect both human, plants and water creatures negatively.
Extreme selenium level observed in fish after sampling indicated that its impact exceeded safety threshold for human consumption (Letcher & Clement, 2015). Toxic pollutants including vanadium, iron and manganese are health hazards and threatened lives of people and the population of fish. Also, the toxic level of the lake made its water less susceptible to consumption due to high level of MCLGs in the water as stated by the Safe Drinking Water Act. Additionally, the impact of the pollutants extended to the land and polluted the soil due to toxic spills. In addition, adverse spills with high level of liquid strength eroded the soil causation soil sediments to the lake, which added mud to the water body.
Physical and Chemical characteristics of the Waste
Common waste pollutants comprise of copper, iron, vanadium, lead, selenium and silver. The wastes are heavy metals and have adverse impact when consumed due to their extreme health implications. Also, chemical reactions such as oxidation worsens the situation by making metal soluble to water which in turn enhances their impact when they are dissolved in water. For instance, when such chemicals are consumed, they initiate blood level poisoning in children as well as lowering their intelligent quotient. Adverse occasions may lead to impairment related to neurobehavioral development in human when their intake is high. Prolonged exposure to hard metals impacts the brain and triggers gastrointestinal disease (Letcher & Clement, 2015). However, not all metallic components are soluble in water, their deposits corrodes water reservoirs hindering water preservation. Moreover, the said toxic metals ionizes water in the lake raising its pH, which further impacts the life of water creatures as well as plants.
Which of these do you think could have contributed the
most? Take a position and defend it, using at least one outside resource
Pollution of water in the lake is attributed by poor regulation and compromised management of the site that deters its conservancy. Specifically, management, construction and maintenance of mining corporations are regulated by rules and regulations that ensure standards are met to uphold both human and environmental safety. Mount Polley Mine Corporation violated the stipulated regulations that govern the standards of operation of its activities. Its tailing dam collapsed during its construction compromising the underlying earth layer of glacial till that is unaccounted to date (Letcher & Clement, 2015). It is a requirement that the company engineering team investigates the structure and the composition of the underlying geology alongside evaluating its strengths. Since there is no sufficient evidence demonstrating that the dam collapsed out of pressure from within, caution has to be taken to ensure that high standards are observed to prevent chances of risk.
Factor contributing to the Accident
Absence of an outlet for the tailing dam may be the main factor that contributed to its flooding for over four square kilometers. Closed dams without outlets build up pressure due to too much weight of water. Based on the tailing dam case, the dam was constructed without the consideration of the structures holding capacity that contributed to its collapse and flooding due to inability to withstand vast water capacity. The flooding led to loss of people’s lives alongside animals and their habitats (Letcher & Clement, 2015). In addition, the disaster impacted the environment negatively through soil erosion and contamination. Additionally, loss of biodiversity and ecological imbalances comprise the impacts that are observable until today. Therefore, the flooding incident is linked to irresponsible construction and tailing pond’s substandard infrastructure.
Letcher, T. M., &Clement, G. Y. (2015). Heavy Metals Toxicity & the Environment. US National Library of Medicine: National Institute of Health.