M. R. Azom
Civil and Environmental Engineering Department of Islamic University of Technology (IUT), Gazipur, Bangladesh.
K. Mahmud
Civil and Environmental Engineering Department of Islamic University of Technology (IUT), Gazipur, Bangladesh
S. M. Yahya
Civil and Environmental Engineering Department of Islamic University of Technology (IUT), Gazipur, Bangladesh
A. Sontu
Civil and Environmental Engineering Department of Islamic University of Technology (IUT), Gazipur, Bangladesh.
S. B. Himon
Civil and Environmental Engineering Department of Islamic University of Technology (IUT), Gazipur, Bangladesh
Environmental pollution, Impact assessment, Health hazards, Mitigation measures.
Risk Management in Agriculture
The study was conducted by a series of following tasks: 1) Visit tanneries and surrounding areas. 2) On-site assessments and interviews with relevant personnel including workers, managers, and other stakeholders. 3) Preparation of EIA report from the interviews. 4) To suggest some mitigation measures to save the surrounding environment from further degradation. A. Study Area The study was conducted at Shahjalal Tannery and Latif Tannery which are situated in the tanning industrial area of Hazaribag, Dhaka the capital of Bangladesh. The location is just adjacent to the Hazaribag Police Station and river Buriganga. Most of the surroundings are covered by other tanneries, houses, schools. There are many permanent and non-permanent settlements adjacent to the industries. V. ENVIRONMENTAL IMPACT ASSESSMENT Environmental Impact Assessment (EIA) is the assessment of the beneficial and adverse changes in environmental resources or values resulting from industry or any development project. The EIA process of an industry essentially comprises of three sequential elements: 1) Identification of all potentially positive and negative impacts on the natural and human environment resulting from industry. 2) Evaluation or assessment which includes quantification of the identified impacts with respect to a common base and with respect to impacts from other industrial actions. 3) Preparation of a mitigation plan which upon implementation, will reduce or offset the potentially significant negative impacts to acceptable levels. This reduction may result from the implementation of industrial production process alternatives or modifications or environmental protection measures. The plan simply reduces the number or magnitude of adverse impacts. The EIA process may also include a monitoring plan to observe the performance of the mitigation plan adopted for the protection of the environment from degradation and to review the environmental changes during the implementation and operation of the industry. 1) The Method of Assessment: Considering the situation prevailing in the country, a simple methodology was taken for EIA of the tannery. The methodology is based on Environmental Evaluation System (EES). In EIA broader definition of environment is used and takes into account almost all environmental components considering Physical, Chemical, Biological, Ecological, Sociological, Cultural, Economical and Operational aspects. These various components influence the selection of parameters. In Bangladesh, in the absence of a database, it is only possible to estimate the potential environmental changes from the existing situation. In this method, the background environmental conditions were the reference level and the positive and negative changes in environmental conditions resulting from the tanneries were evaluated. The computation of Environmental Impact Value (EIV) needs determination of Vi , the value representing the magnitude of alteration of the environmental parameters, and Wi , the value representing relative weight or importance of the respective parameters. 2) Magnitude of Environmental Alterations: The beneficial and adverse changes in environmental parameters resulting from a tannery, usually expressed in qualitative terms are plotted in a scale to quantify the environmental alterations. Since the changes of environmental parameters are measured with respect to background conditions, no change has 0 values. The adverse changes have been given values -1, -2, -3, -4 and -5 to represent very low, low, moderate, high and severe negative impacts respectively. Similarly, +1, +2, +3, +4 and +5 represent very low, low, moderate, high and very high positive impacts respectively. A value from the scale representing the effect of the project on each parameter was taken to compute the EIV of the tannery. 3) Relative Importance of Environmental Parameters: The EES methodology is based on the assignment of an important unit to each parameter by the judgment of professional experts consists of chemists, biologists, civil engineers, environmental engineers, agricultural scientists, social scientists and urban planners. But in this study due to the absence of proper guidelines for selecting parameters and assigning importance value, judgment was used considering the surrounding environmental condition and some parameters were adopted from Battelle Environmental Evaluation System. All environmental parameters influenced by the tannery are not of equal importance or weight. The importance of a parameter varies from country to country depending on the environmental concerns of the country. In Bangladesh, flood, employment, agriculture, fisheries, etc. carry more importance than many others. The parameters related to tannery industries were given different values based on prevailing environmental concerns in Bangladesh and are presented in Table I. The values representing the importance or weight of the parameters can be used to compute the relative impacts of the parameters which are then summed up to obtain the total EIV. However, this method has the following significant drawbacks: 1) The input judgments are not quantified efficiently. 2) It does not consider the consistency of judgments. 3) Only neighboring parameters in the list are directly compared.
International Journal of Environmental Science and Development, Vol. 3, No. 2, April 2012
Journal