Tehlikeli maddelerin çevresel risk değerlendirmesi

Abstract

Tehlikeli maddeler, yaşam standartlarını ve refah düzeyini arttırmadaki yadsınamaz özellikleri yanında çevresel riskleri özellikle insan sağlığına olumsuz etkileri ve kaza sonucu oluşan felaketleri göz önüne alındığında sayılarının da yüz binleri bulacak kadar çok olması sonucu yönetimleri açısından karşı karşıya kaldığımız problemlerin karmaşıklığı açıkça ortaya çıkmaktadır. Dünya üzerindeki uygulamalara bakıldığında, tehlikeli madde yönetimindeki ağırlığın çevresel risk değerlendirme noktasında çoğunlukla çevrenin en önemli ancak tek faktörü olmayan insana yönelik doğrudan etkiler üzerinde olduğu, insan faktörü dışındaki diğer çevre bileşenleri üzerinde pek kayda değer bir yaklaşımın sergilenmediği görülmektedir. Bu çalışmada, çevre etki değerlendirmesi ve çevresel risk değerlendirmesi yaklaşımlarından yararlanılarak halihazırda geçerli olan tehlikeli madde yönetim biçimlerine yukarıda bahsedilen eksiklik çerçevesinde bütünsel bir çevresel boyut (insan dışındaki diğer çevre bileşenlerini de içine alan) ve yeni bir yaklaşım getirilmeye çalışılmıştır. Bu yaklaşımda, temel değerlendirme bağlantısı bölgesel bir ekosistem olarak ele alınmıştır. Bu yaklaşımı ortaya çıkarabilmek için konu ile ilgili kavram karışıklıklarının giderilebilmesi yolunda gerekli tanım ve kavramlar da verilerek sırası ile tehlikeli maddelerin özellikleri, sınıflandırılmaları, ülkemizdeki ve dünyadaki yönetim ve yasal çerçevedeki yeri, çevresel risk değerlendirmeleri ve tehlikeli madde kazaları ve eylem planlarını da kapsayan detaylı bir literatür araştırması yapılmıştır. Bu çalışma ile getirilen bazı öneriler ise; Tehlikeli maddeler için tehlikeli madde veri tablolarının oluşturarak bir bilgi bankası oluşturulması, ? Tehlikeli maddelere ait kısa ve uzun vadeli çevresel risk tahminleri yapılarak çevresel risk değerlendirmesi ve hatta çevresel etki değerlendirmesi yapılması, ? Tehlikeli maddelerin risk oranları baz alınarak müdahale için kolaylık sağlanması için daha az sayıda gruplar halinde sınıflandırılması, ? Tehlikeli maddenin üretiminden yani doğumundan düşman oluşuna kadarki evreleri belirlenerek korunma planlan üretilmelidir. Bu planlarda o maddenin kullanım oranları, üretimleri, teknolojileri ve ekonomileri karar vericiler tarafından yönlendirilmiş olmalıdır. ? Tehlikeli maddenin akut veya ani kaza, dökülme gibi irade dışı davranışları için hazırlıklı olunmalıdır. Bu risk tahminleri ile yapılan tüm değerlendirmeleri gözönüne alarak ilk müdahaleden önceki planlama adımı olmalıdır. ? ilk müdahale, veya acil eylem planları hazırlıklı olmanın gereği olarak hazır tutulmalıdır. Bu planlamada en aza indirilmiş sayıda rehberler kullanılmalıdır. ? İlk müdahale planını uygulanmasından sonra tehlikeli maddenin hangi yolla olur ise olsun tahribatını ve etkisini tespit etmek gereklidir. Aynı zamanda müdahale sonrası uzun süreli etkiler ve onların sonuçları tahmin edilerek iyileştirme çalışmalarını başlatan planlar yapılmalıdır. Bu planlar, bilgi toplama ve hazırlıklı olma aşamaları ile bağlantılı olmalıdır. şeklinde özetlenebilir.

Prior to the Industrial Revolution, disasters were primarily limited to those caused by natural events like floods, earthquakes, and volcanoes. While disasters still result from such causes today, we are now confronted with others that are relatively unique to the twentieth century. One such cause directly relates to the materials used industrially to produce the amenities of modern life by the chemical, petroleum and nuclear industries. For instance, just consider one product of the chemical industry, vinyl chloride. This raw material is used to make the synthetic plastic PVC. As vinyl chloride is a highly flammable substance, it has a severe fire and explosion hazard. When released from its container, vinyl chloride poses a substantial threat to public health and safety. Bulk quantities of this substance are likely to be encountered in the workplace during storage or handling or during shipment. Vinyl chloride is a single example of a substance that has come to be known as a hazardous material where in general terms, a hazardous material is defined as a material with a substantial potential to pose a danger to living organisms, materials, structures or the environment. Such dangers may consist of explosion or fire hazards, corrosion, toxicity to organisms or other detrimental effects. Hazardous materials may be found in a variety of places even in the home. Some are found dispersed in the air we breath; others are even in the food we eat and the water we drink. In truth, hazardous materials are likely to be found almost anywhere. One of the difficulties in dealing with the hazardous materials is the variety of chemicals that are found in our world today. The results of several studies show that there are between 5 and 6 million chemicals and formulations. A computer review of the total list of Chemical Abstract Service indicated that 1.5 million of these chemicals were common, with 33000 to 63000 of them considered hazardous. To complicate matters, these "hazardous chemicals "are known by 183000 different names. These huge number of hazardous materials are generally classified as follows: ? Class 1 : Explosives (with 5 divisions) ? Class 2: Gases (four divisions) ? Class 3: Flammable liquids (three divisions) ? Class 4: Flammable solids; spontaneously combustible materials; and materials that are dangerous when wet ? Class 5: Oxidizers and organic peroxides ? Class 6: Poisons and etiologic materials ? Class 7: Radioactive materials xvii ? Class 8: Corrosives ? Class 9: Miscellaneous and finally «ORM-D: Other regulated material For indicating and ranking the health, flammability, and reactivity hazards of hazardous materials, The National Fire Protection Association (NFPA) has developed a standard system (NFPA 704). In addition, a special precaution symbol may be used where necessary. This system of identifying hazards associated with various materials was developed primarily for fire protection and emergency personnel but can be useful to anyone who needs to handle potentially hazardous material. As stated in NFPA 704, 'This standard provides a simple system of readily recognisable and easily understood markings, which will give at a glance a general idea of the inherent hazards of any material and the order of severity of these hazards as they relate to fire prevention, exposure, and control". Hazardous materials may be acutely toxic or have long-term chronic effects, even at low concentrations. They include a large number of organic compounds, and a number of inorganic substances, heavy metals, for instance. Millions of kilograms of hazardous materials are transported daily along the highways, railways and waterways. Some of these materials, such as cyclic pesticides, cyanide, organometallic compounds and heavy metals are highly toxic to man and environment, and the accidental release of even small volumes of those materials to the environment may have serious consequences. Accidental spills and releases of hazardous substances can result from a variety of causes including highway, rail, water, industrial plant upsets, the failure of retaining dikes, storm damage, malicious acts, and even air accidents. The cost of returning the environment to an acceptable state following a spill may involve the expenditure of millions of dollars, and even after toxicants have been removed from a spill area, undesirable effects may linger in the environment for many months or years. Hazardous material spills may impair the quality of water, land or air, or all three simultaneously. A land of spill of a non-volatile, toxic substance generally has less impact on the environment than a spill of a highly volatile, toxic substance or a substance that hazardous substance entered a waterway. Land spills can normally be contained and the containment soil removed to a disposal area, localising the effects of the incident. Where air or water contamination is involved, the fluidity of these media favours the transport of highly hazardous substances over a wide area with possible dangerous consequences. Once released to the atmosphere, diffusion and wind currents rapidly disperse vapours and containment is possible. A community rating and evaluation system developed by University of Western Ontario, Canada to find population and environmental hazards in a community has been described and a previous study conducted to find out the index or an indicator of a toxic spill incident that might happen in bosphorus and its environment is evaluated. Rating values for that study were accounted for the highway, railway, marine and pipeline transport plus the industrial and storage handling of these materials. As a result of that study it can be said that the examined area exceeds the limit values for the environmental hazard rating and should be evaluated in the class of cities having disaster potential. In the early 1970s, intensive efforts were started to develop systems to meet environmental emergencies. Before this time, the emphasis was placed on the development of effective ways to identify hazardous substances, to define physical XVI» hazards associated with the handling of these substances, and develop emergency first aid procedures. Starting in 1970, increasing attention has been directed toward the environmental effects of pollutants and the development of procedures to prevent and cope with emergencies. The primary purpose of emergency plans is to prevent incidents as well as to initiate timely, well organised responses. When developing an emergency plan for a given area, it is necessary to involve many agencies and personnel in the creation of a network of facilities that must function rapidly and precisely in the event of an emergency. It is of utmost importance that an accident be reported as soon as possible and those effective actions follow forthwith. The spilled substance has to be identified, appropriate personnel and equipment have to be rushed to the scene, and the cleanup has to be accomplished without endangering human life, while holding environmental damage to a minimum. The 1996 North American Emergency Response Guidebook (NAERG96) was developed for use by fire fighters, police, and other emergency services personnel who may be the first to arrive at the scene of a transportation incident involving dangerous goods. It is primarily a guide to aid first responders in quickly identifying the specific or generic hazards of the material(s) involved in the incident, and protecting themselves and the general public during the initial response phase of the incident. The guidebook assists responders in making initial decisions upon arriving at the scene of a dangerous goods incident. It is primarily designed for use at a dangerous goods incident occurring on a highway or railroad. All guides have been revised and are now presented in a two-page format and identified by three digit numbers. Since many materials represent similar types of hazards that call for similar initial emergency response actions, only a limited number of guides are required. The orange-bordered guides are not applicable when materials of different classes and/or divisions are involved in an incident and are intermingled. Incidents involving more than one class of material require the incident commander to obtain informed advice as soon as the scope of the incident can be determined. Materials involved in an incident may, by themselves, be nonhazardous; however, a combination of several materials or the involvement of a single material in a fire, may still produce serious health, fire or explosion hazards. Figure! illustrates the steps to find out the appropriate guide during an emergency. In this study, a new approach shown in the Figure2 below is designed to manage the hazardous materials. That approach considers environmental impact assessment and environmental risk assessment together. From the literature review it is seen that there is a need to involve all components of the environment not only man while managing hazardous materials in our community. Some of the propositions made following this study are; ? The control and response activities of hazardous materials should use the same language as it is in traffic for instance. ? As our legislations are lack of enforcement not only amendments should be made but also the institutions to cope with the developments in this area should be established. ? Hazardous material data sheets should be prepared for the materials including the physical, chemical and biological properties of the material, the response information in terms of evacuation distances, fist aid, protective equipment etc. XIX Hazardous material incident yes ID no present on the placard or orange panel?.1 no ID no present on packaging or shipping paper? no Material name present on placard, packaging or shipping paper? yes....,ir.^-..-X ; ID No index Name index Guide no ?^ Placard present? /yes \ Search placard from placards table Thought of hazardous material presence? yes Apply Guidel 11 and watch for additional date Figure 1. Steps of finding out the appropriate Guide during a hazardous material incident xx Information ? Descriptions » Properties. Classification » Potential hazards Forbid production and distribution Risk estimation expfosivity corrosivtty toxicity radioactivity flammabitity infectious carcinogens contanimation Environmental area inventory « Population indexes * Settlement > Social life. Industry ? Climate ? Jeology- hydrogeology ? Ffora^auna... Environmental standarts Forbid production and distribution t INCIDENT Shipment Environmental protection i USAGE Exposure FOOD CHAIN Distribution ? Prevention ? Preparedness ? Response ? Recovery Figure 2. Basic considerations in hazardous material management