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31.
The open pit mining nearby shoreline is planned to be extended into below sea level in order to use additional reserves of
the cement raw material (marl). The raw material is currently contaminated by seawater intrusion below a depth of 20 m up
to the distance of 90 m from shoreline. Seawater intrusion related contamination of the material used for the cement production
was investigated by means of diffusion process for the future two below sea level mining scenarios covering 43 years of period.
According to the results, chloride concentrations higher than the tolerable limit of a cement raw material would be present
in the material about 10–25 cm inward from each discontinuity surface, controlling groundwater flow, located between 170 and
300 m landward from the shoreline at below sea level mining depths of 0–30 m. The estimations suggest that total amounts of
dilution required for the contaminated raw material to reduce its concentration level to the tolerance limit with uncontaminated
raw material are about 113- to 124-fold for scenario I (13 years of below sea level mining after 30 years of above sea level
mining) and about 126- to 138-fold for scenario II (43 years of simultaneous above and below sea level minings). 相似文献
32.
The concentrations of Cr, Mn, Fe, Ni, Cu, Zn, and Pb metals in soil samples (N = 21) were determined by flame atomic absorption spectrometry. The modified Community Bureau of Reference (BCR) sequential extraction procedure (three‐step) was used in order to evaluate mobility, availability, and persistence of heavy metals in soil samples taken from an agricultural area in Erciyes University Campus. The operationally defined fractions isolated using the BCR procedure were: acid extractable, reducible, and oxidizable. The mobility sequence based on the sum of the BCR sequential extraction stages was: Mn (70.2%) > Pb (62.9%) > Ni (26.7%) > Cr (15.4%) > Zn (14.4%) > Cu (12.9%) > Fe (1.24%). Multivariate statistical analysis was used to define the possible origin of heavy metals in soils. Correlation analysis, principal component analysis (PCA), and cluster analysis (CA) were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of heavy metals. PCA results revealed that the sampling area was mainly influenced from three sources, namely natural, airborne emissions from domestic heating and traffic. 相似文献
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34.
Landfill site selection by using geographic information systems 总被引：3，自引：3，他引：3
One of the serious and growing potential problems in most large urban areas is the shortage of land for waste disposal. Although
there are some efforts to reduce and recover the waste, disposal in landfills is still the most common method for waste destination.
An inappropriate landfill site may have negative environmental, economic and ecological impacts. Therefore, it should be selected
carefully by considering both regulations and constraints on other sources. In this study, candidate sites for an appropriate
landfill area in the vicinity of Ankara are determined by using the integration of geographic information systems and multicriteria
decision analysis (MCDA). For this purpose, 16 input map layers including topography, settlements (urban centers and villages),
roads (Highway E90 and village roads), railways, airport, wetlands, infrastructures (pipelines and power lines), slope, geology,
land use, floodplains, aquifers and surface water are prepared and two different MCDA methods (simple additive weighting and
analytic hierarchy process) are implemented to a geographical information system. Comparison of the maps produced by these
two different methods shows that both methods yield conformable results. Field checks also confirm that the candidate sites
agree well with the selected criteria. 相似文献