Wednesday, May 6, 2020
Environmental Management for Sustainable Development Specialized Gra
Question: Describe about the Environmental Management for Sustainable Development for Specialized Granite. Answer: A large part of southern Nova Scotia is made up of granites (South Mountain Batholith) (375-380 million years old) exposed at surface. What plate tectonic and geological conditions were necessary to produce this large volume of granite? How could these rocks become exposed at surface? Why is the South Mountain Batholith considered to be a Specialized Granite? How did the Granite uranium vein type deposits form? What genetic relationship would the uranium occurrences in the granite have with the younger uranium roll front deposits in the Horton Group (Carboniferous, 355 million years old) sedimentary rocks? (Give references to support your answer). The granites in the Southern Nova Scotia is formed due to various geological reasons in the South Mountain Batholith region. The collisions of Armorican with the Laurentia-Baltica results in the creation of massive batholiths and are thereby responsible for forming groups of plutons. Importantly, the granite batholiths in Nova Scotia are created in two different ways; the first being continental collision and second is subduction. These rocks are exposed to surface with the process termed as erosion and that is accelerated by the uplifting of continental region over million to hundreds of years. The process removes the overlying rocks and thereby exposes the deeply buried batholiths. The South mountain batholith is considered to be as specialized granite. The granite deposits and occurrences found in the Meguma zone are created in the geochemically specialized interferences of leucomonzo granite, monzo granite and leuco granite. It has been found that the existence of 40Ar-39 and Rb-Sr proves the presence of specialized plutons as carboniferous in South mountain batholith. The same reason is further attributed to the fact that this is termed as specialized granite. The vein uranium deposits are formed as a result of the epigenetic concentrations of the uranium minerals, primarily the pitchblende and the coffinite. These uranium minerals are the only metallic constituents within the veins and are supplemented along with other minerals such as cobalt, copper, silver, nickel and bismuth. Furthermore, these deposits are presented by the intra granitic veins and the peri batholithic veins. The uranium deposits found in the granitoid rocks in the south mountain batholith of Nova Scotia is formed with the fluid migration. These are formed within the shear and fracture zones, which is genetically similar to the uranium roll. Note that these front mainly deposits in the Horton group strata as layer over layers formed through years, which are also referred as carboniferous, and are 355 million years old (Shellnutt Dostal, 2015). A company has hired you to undertake an environmental radioactivity assessment on the area surrounding the town of Tatamagouche, Cumberland County, Nova Scotia (see map 1 from assignment 2). The company wants to build a large resort near the town along the Northumberland Strait. The company has hired you assess the radioactive environmental risks in the area. What are the risks? What kind of uranium enrichment has taken place in the rocks of the area? If the resort has to depend on drilled wells to provide water, what might be some of the problems they might encounter? Given that you must locate a site in this area, what procedures would you undertake to assess the risks and recommend a location? What are the remedial steps that you would recommend at the resort during construction or after it is built? (Give references where applicable) Being an in-charge of supervising the radioactivity effect in the area of Tatamagouche, Cumberland county, I would like to evaluate the effects and will analyse the risks of the radioactivity in this region. The risks of radioactivity in Northumberland are required to be considered seriously as they can be causative towards blood cancer, known as leukaemia; and are probable to affect the community members being exposed to radioactive contents. The affected area of the body by radiation makes the cells to get divided and develop quickly, making the DNA damaged. It has been reported the existence of numerous uranium near the area of Northumberland Strait; Nova Scotia is liable to risk humanity. The uranium enrichment in these areas is mostly of two types (1) carbon and pyrite-related quartz sandstone type and (2) hematite arkosic sandstone type. The former one is dominated with a large number of quartz-rich coarse to fine grained sandstone. Moreover, in the uranium enriched sandstone beds the arkosic type have plenty of dolomitic cement and in mineralised form carbonates are found in the shape of dolomite-calcite veins within the fractures. Depending upon the drilled wells for water the resort will face trouble, as there is a water shortage in these areas of Nova Scotia as it prohibited the flowing water in the drilled wells. According to the report of OBrein et al. (2014), it is accounted that drilled wells have higher radon values than the dug wells, which further results in a shortage of water. Another suitable area for the construction of the resort in Nova Scotia is the Horton Group Strata of the Windsor area. In order to overcome the effect of the radiation, the company should take proper radiation protection measures and can even avoid deadly disease like cancer in these regions. It should prefer over dug wells and other means than drilled wells for water. Other than this, safe dumping of radioactive material and close inspection of community health is essential after the construction. You have been given the task to locate a high-level nuclear waste disposal site somewhere in Canada. What would be the criteria for locating a site? How might you test the site before proceeding with construction? What about the social aspects of the disposal site selection, how could these be overcome? What kind of monitoring would have to be done on the site after it started operation to assure health and safety? How would this site compare to a disposal for low level radioactive material? Why has there not been a permanent disposal site in Canada before now? (Give references) The radioactivity of used nuclear fuel is very high and thus it needs a site for its proper disposal. According to Canadas nuclear power program, the research mainly focussed upon the recycling of the useful and necessary parts of the used fuels and disposing of the remaining parts. It has focused on long-term management of the highly radioactive wastes using the concept of Deep Geological Disposal (DGD) (Stone, 2016). The criteria for selecting for the radioactive waste disposal must follow the Deep Geological Repository (DGR) protocols, which is being proposed by Ontario Power generation. According to the guidelines of DGR, recovered from the various nuclear generating station, will be finally received at the waste packaging area of DGR and then finally disposed into the underground repository of the selected location. Nuclear power disposal is a major issue and concern for the nuclear power generation. The company should follow certain guidelines to ensure the safety and minimum risk to life, such as using TLD batch for workers, using protective equipment during work, and providing appropriate protection as well as education to people who are working in close proximity of exposure. Notably, the social aspects faced by the companies for selecting a disposal site tends to face problems which may be due to the local residents. In order to overcome this situation, a site far away for a residential area and reach of common people should be selected. Transportation of the waste to the disposal site should be given proper care, to avoid any accident in the vicinity, it must have fencing and notification board. Note that followed by disposal, the underground water in the particular area should not be used by the residents close to the epicentre, as it is contaminated due to radioactive leakage. The health measures that are critical to being implemented in the locality include regular check-up of community members, providing proper education, and routine testing of water and soil for radioactive detection. Another significant concern in this regard are linked to low level radioactive waste generates from milling, uranium mining and mill tailings. According to AECL, these wastes should be disposed of through improved sand Trench which needs 150 years of isolation. The reason that permanent disposal of radioactive wastes is not possible for Canada because of the economic issues. On the other hand, scientifically, the half-life of a radioactive substance is in billion years and that it has the potential to risk the community member upon exposure. Hence the only possible solution is following the guidelines and making the radioactive substance dump in a location far away from residential reach. References: OBrien, K. E., Risk, D., Rainham, D., OBeirne-Ryan, A. M. (2014). Using field analogue soil column experiments to quantify radon-222 gas migration and transport through soils and bedrock of Halifax, Nova Scotia, Canada.Environmental Earth Sciences,72(7), 2607-2620. Shellnutt, J. G., Dostal, J. (2015). Granodiorites of the South Mountain Batholith (Nova Scotia, Canada) derived by partial melting of Avalonia granulite rocks beneath the Meguma terrane: Implications for the heat source of the Late Devonian granites of the Northern Appalachians.Tectonophysics,655, 206-212. Stone, W., Kroukamp, O., Moes, A., McKelvie, J., Korber, D. R., Wolfaardt, G. M. (2016). Measuring microbial metabolism in atypical environments: Bentonite in used nuclear fuel storage.Journal of microbiological methods,120, 79-90.
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