By Name Essay Example

  • Category:
    Other
  • Document type:
    Assignment
  • Level:
    Undergraduate
  • Page:
    3
  • Words:
    1705

HAZARDOUS WASTE AND CONTAMINATED SITES

HAZARDOUS WASTE AND CONTAMINATED SITES

Hazardous Waste and Contaminated Sites

Introduction

Contaminated sites cleanups as well as regulation of hazardous waste are two crucial elements of contemporary public environmental protection policy. Undoubtedly, every country produces wastes, which may be dangerous to the environment as well as human health. Even though the precise description of a hazardous waste differs across regulatory command, Mueller et al. (2007, p.776) posits that hazardous waste usually entails any thrown-away material that is possibly harmful owing to its toxicity, corrosivity, and ignitability. Producers of hazardous waste do not consist of just bigger industrial plants, like petroleum refiners together with chemical manufacturers, but as well smaller facilities, like photo finishers, and even entities owned by government, like infirmaries. U.S. is one of the leading generators of hazardous waste, since it has more than 600,000 large as well as small generators of hazardous waste. Besides the continuing generation of hazardous waste, scores of countries have devastating land contamination from previous disposal of hazardous waste as well as utilisation and storage of toxic substance (Mueller et al., 2007, p.777). Most countries do have a lot of major sites (as well as scores of more minor sites) that are subject to responses to deal with this contamination. The report seeks to examine in detail one case study (Mercury contaminated site at Minamata Bay, Japan) of a contaminated site.

Case Study

One of the most life-threatening occurrences of industrial contamination as well as mercury poisoning took place in the 1950s, at Minamata, Japan. Chisso Corporation, which was a local plastics and petrochemical company, discarded almost 27 tons of methylmercury into the Minamata Bay for almost four decades (Tomiyasu et al., 2006, p.284). The Chisso Corporation first begun with the production of acetaldehyde in 1932, manufacturing 210 tons yearly, and the production jumped to 6,000 tons yearly by 1951: This was more than 50% of total output in Japan. In the company, mercury was utilised as a catalyst in the acetaldehyde production, which according to (Tomiyasu et al., 2006, p.285) is a chemical used in the plastics manufacturing. The process by product (Methylmercury-contaminated) was drained into the bay, generating an extremely poisonous environment that resulted in contamination of the local fish. Minamata residents, who depended heavily on fish for food, were in danger of contact to methylmercury from the fish they relied for food. The high levels of contamination in the Minamata residents resulted to serious neurological damage; thus, killing over 900 people. What’s more, almost 2 million individuals from Minamata suffered physical condition predicaments or were left enduringly handicapped from the contamination. According to Tomiyasu et al. (2006, p.286), this type of perniciousness in humans is these days acknowledged as Minamata disease. Symptoms of this disease consisted of four extremities’ sensory disorders, lack of sensation, blindness, hearing as well as smell impairments, cerebellar ataxia, in addition to disequilibrium disorder. More dangerous cases resulted in paroxysms, paralysis, seizures, as well as probably death. Besides the outbreak amongst the people of Minamata, the disease was detected in babies born to mothers who were affected by the contamination.

Treatment strategies of environmentally contaminated sites

Basically, the hazardous waste residues and contamination in soils is a vital concern in establishing the suitable treatment strategy. A number of industrial residues such as Lead metal are poisonous, while certain environment contamination that occurring naturally have a reduced toxicity for the reason that scores of natural mineral such as lead metal possess low bioavailability. Low bioavailability according to Efroymson et al. (2004, p.319) signifies that the naturally occurring metals can go through a person’s digestion system practically unabsorbed. Therefore, if toxic compounds can be transformed to naturally occurring forms in that case contaminated sites can be rendered secure, even for people occupancy as well as agriculture, even though selection of crop will be restricted to those plants that uptake low toxic compounds. Furthermore, waste residue as well as soil categorization will be a fundamental factor to establish a suitable treatment strategy. The treatment strategy must make allowances for the toxicity as well as the encapsulation of the contaminant, since such features directly impact on bioavailability and solubility. As such attributes are site specific, Efroymson et al. (2004, p.321) posit that it is extremely imperative to prepare treatment strategies on real field sampling and amassed exposure data. Fundamentally the treatment strategies of environmentally contaminated sites include; removal as well as replacement of contaminated soils through treatment of contaminated soils to safe levels and afterward take back the treated soils to original site. Another strategy is treatments involving the contaminants’ transformation through chemical, biological, and thermal treatment techniques that can be utilised onsite or offsite. Another imperative treatment strategy is contaminants immobilization, which includes restriction of landfill residues as well as containment technologies.

Effectiveness of remedial strategies

Essentially, remedial strategiesare not meant to create a site that is completely uncomplicated or site that is faultlessly clean. There subsist lots form of site contamination, which by and large do not cause any momentous damage; however, in particular situations and in certain concentrations they can bring life-threatening damage as seen in the case of Mercury contaminated site at Minamata Bay. In this regard, the aim of remedial strategies is to stop the contaminants from reaching the waterways, plants, and people that can be impacted adversely. Remedial strategies that cover contaminated site can undoubtedly decrease the risk presented. If remedial strategies are espoused wholly they can bring contaminated soil to the surface, and importantly the strategy helps to appropriately disposed of or covered on-site.  Besides that, sites polluted by historical pesticide utilisation, like farmland, can with the help of remedial strategies be developed for any site utilisation, which includes residential use, making use of institutional as well as appropriate engineering control.

Problems site contamination poses to the environment

Water contamination: Site contamination can result to water pollution, whereby industrial hazardous waste are released into rivers, lakes, as well as other water bodies; thus, making life in water no more hospitable. People contaminate water with enormous scale discarding of household waste and garbage and waste from factories. In scores of countryside areas, people use the contaminated water to cook and drink making it extremely dirty. Contaminated sites also lead to acid rain, which further increase contamination level in the water. Other than these, thermal contamination as well as the exhaustion of dissolved oxygen exacerbates the already aggravated state of affairs of the water bodies. As observed in the aforementioned case study, water contamination impacted the fish used by people for food. Soil contamination is an end-result of contaminated water, acid rain, fertilizers and so on, which leads to contaminated crops. Soil contamination take places when chemicals are discharged by spill or a leakage from underground chemical storage tank which discharges heavy pollutants into the soil. Such contaminants may consist of heavy metals, chlorinated hydrocarbons, pesticides, herbicides, and Methyl Tertiary Butyl Ether (MTBE). These contaminants affects vegetation around the contaminated site, making it hard for vegetations to grow in that site, and results in severe health problems.

Methods to remediate contaminated sites

In-Situ Catalyzed Peroxide Remediation. This method has the potential for hastily treating soils contaminated with relentless organic and poisonous wastes. One way for introducing well-built oxidants into soils that haven contaminated is the catalyzed hydrogen peroxide decomposition to create the hydroxyl radical.

Cover systems: They offer a stabilization method by decreasing the amount of water through-put in a retention basin or burial trench. In this case, the cover usually is made up of a surface layer that holds up plant life, a drainage layer, a gas-venting layer, and a low-permeability layer. Importantly, the site requirements prescribe which layers are essential, and a number of sites will not require all layers.

Incineration Technologies: a number of incinerators can be used to remediate contaminated sites and, they include: fluidized bed, plasma arc, liquid injection, infrared furnaces, and the manifold hearths. In this case, incinerators can be used to volatilize and combust hazardous wastes at temperatures ranging from 870 to 1,200° C.

In-Situ Grouting: shallow landfills in-situ grouting has been utilised to successfully manage the inflow of surface water, in consequence decreasing leach rates, into sites of hazardous waste. Soil Washing that can be used to remediate contaminated site, bearing mind that previous endeavors focused on extraction through aqueous solutions and overlooked the possibilities of contamination volume reduction (EPA, 2013).

Alternative remediation procedures that could have been used

In the above case study, the company should have employed solidification method, since the method could have reduced Methylmercury-contamination by converting the company’s waste into its least toxic, mobile, or soluble form. Importantly, the waste physical nature is not essentially altered in process of the stabilization. Modern companies can use remediation technologies screening matrix since the matrix permits the company to screen through ex situ as well as in situ technologies for either groundwater or soil remediation (EPA, 2013). Variables that can be used by a company in screening consist of contaminants, cleanup time, overall cost, and development status.

Conclusion

In conclusion it has been argued that sites that are contaminated contain substances under or in the land that are truly or potentially unsafe to the environment or health. The report has discussed how Chisso
Corporation careless disposal of methylmercury into the Minamata Bay lead to death of many people in and around the area. What’s more a number of problems site contamination poses to the environment have been discussed and they include water and soil contamination. Finally, important methods to remediate contaminated sites includeIn-Situ Catalyzed Peroxide Remediation, Cover systems, Incineration Technologies, In-Situ Grouting, and Soil Washing.

References

Efroymson, R.A., Nicolette, J.P. & Suter, G.W.I., 2004. A Framework for Net Environmental Benefit Analysis for Remediation or Restoration of Contaminated Sites. Environmental Management, vol. 34, no. 3, pp.315-3631.

EPA, 2013. Remediation Technologies. [Online] Available at: http://www.epa.gov/superfund/remedytech/remed.htm [Accessed 4 June 2014].

Mueller, B.A., Kuehn, C.M., Shapiro-Mendoza, C.K. & Tomashek, K.M., 2007. Fetal Deaths and Proximity to Hazardous Waste Sites in Washington State. Environmental Health Perspectives, vol. 115, no. 5, pp.776-80.

Tomiyasu, T. et al., 2006. Tomiyasu T, Matsuyama A, Eguchi T, Fuchigami Y, Oki K, Horvat M, Rajar R, Akagi H. The Science of the Total Environment, vol. 368, no. 1, pp.283-90.