A top document, just released by the Gujarat government, has raised a major alarm. Sponsored by the Gujarat State Disaster Management Authority (GSDMA), and prepared by Mumbai-based engineering consultants, Prestels, in collaboration with international risk management consultants, IEM, USA, the document says, “As one of the most developed and industrialized states in India, Gujarat is home to a high number of hazardous chemical industries”, adding, the data provided by the state government’s Directorate of Industrial Safety and Health suggests that nearly 2,000 industrial units out of about 25,000 working under the factories Act are hazard prone.
Categorising these hazard-prone industrial units, the report says, as many as 380 are vulnerable to major accident hazard (MAH), while 1,019 are Type-A units where chemical quantities handled are below the threshold quantity for MAH units and 758 are Type-B units handle hazardous solvents and highly inflammable liquids. Apart from the MAH, Type-A and Type-B units, there are 1,427 units which pose fire and explosion hazard and 1,730 pose toxic hazard, the report adds.
The situation for Gujarat becomes particularly vulnerable because, the report, titled “Gujarat State Industrial Chemical Disaster Management Plan”, says, in Gujarat, the chemical industry “occupies a preeminent position in the industrial sector of Gujarat, contributing to more than 40% of the industrial output.” It adds, ”Almost the entire range of the chemical process industry exists in Gujarat, including hydrocarbon processing/refining products, petrochemicals-polymers and man-made fibres, fertilizers, health care products, plant protection chemicals, dyes, pigments and intermediates, fine chemicals, surface coating products, salt and salt-based products, ceramics, glass, cement, vegetable oils, fats, and detergents.”
Calling it a major manmade hazard which exists over and above natural hazards such as cyclones, earthquakes, flooding, tsunamis, and storm surges, the report says, “A stretch of 400 kilometres from Ahmedabad to Vapi is known as the Golden Corridor. In the Bharuch district, Ankleshwar, situated on the Narmada estuary, is Asia’s largest chemical zone. To support the rapid development of the textile industry in the state post-independence, a large integrated chemical complex came up at Atul in Valsad district. The discovery of oil and gas in Ankleshwar and the surrounding areas led to the building of Gujarat Refinery Ltd, and the downstream units in the form of petrochemical complex (IPCL) and fertilizer complex (GSFC) at Vadodara.”
Then, “major hydrocarbon complexes are located in Vadodara, Bharuch, Surat, and Jamnagar districts. The caustic/chlorine manufacturing plants are located in Mithapur, Veraval, Surendranagar, Vadodara, Dahej, Jhagadia, and Atul. Toxic chemicals such as cyanides are produced in GACL Baroda, Cyanides & Chemicals at Olpad (Surat District). The refinery and the petrochemical complex triggered the development of small and medium scale chemical industries for the production of chemicals first in Nandesari, followed by Vapi, Vatva, Ankleshwar, and other places.”
The report states, “These include Gujarat Refinery, Indian Petrochemicals Ltd. and Gujarat State Fertilizer Co. along with several downstream units in the Jawaharnagar (Koyali) petrochemical complex area; fertilizer plants at Vadodara, Hazira, Bharuch, Kalol, and Kandla; and petrochemical complexes at Vadodara, Dahej, Hazira, and Jamnagar. The caustic/chlorine manufacturing plants are located in Mithapur, Veraval, Surendranagar, Vadodara, Dahej, Jhagadia, and Atul. Toxic chemicals such as cyanides are produced in GACL Baroda, Cyanides & Chemicals at Olpad (Surat District). The refinery and the petrochemical complex triggered the development of small and medium scale chemical industries for the production of chemicals first in Nandesari, followed by Vapi, Vatva, Ankleshwar, and other places.”
In addition to all this, “the state has a Chemical Port Terminal at Dahej. Kandla Port Trust imports and handles the majority of petrochemical products in India. Additionally, two ports in the private sector located in Mundra and Pipavav, handle major petrochemical products. It is expected that port-based mega-chemical industrial estates would be further developed. In addition to the manufacturing industries, there is significant infrastructure for handling chemicals such as pipelines, transportation (rail and road), and isolated storages”, the report says.
It further says, “A cross-country 2,300 km Hazira-Bijapur-Jagdishpur (HBJ) gas pipeline originates from Hazira. A hydrocarbon supply pipeline runs from Kandla to Bhatinda (Punjab). A pipeline network of more than 17,000 km is present in the state. Major LNG terminals are proposed at Pipavav, Dahej and Hazira. The crude oil carrying pipelines are also proposed. Railways, state highways and national highways running through the state carry chemical cargo that originates in or transits through the state. There are several isolated storages mainly at Vadodara, Kheda, Sanand, Bavla, Rajkot, and Bhavnagar.“
It adds, “Major LNG terminals are proposed at Pipavav, Dahej and Hazira, which would necessitate laying of long cross-country pipelines for carrying natural gas. The crude oil carrying pipelines include Salaya-Mathura, Viramgam- Vadodara, and those proposed from Mundra to Punjab State. The petroleum products carrying pipelines include Vadodara-Sabarmati, Kandla-Bhatinda and Jamnagar- Kandla (off-shore). Railways, state highways and national highways running through the state carry chemical cargo that originates in or transits through the state.”
Then there are a total of 183 Gujarat Industrial Development Corporation (GIDC) estates, out of which 13 estates as chemical zones – in Ankleshwar, Dahej, Jhagadia and Panoli (in Bharuch district), Nandesari, Sachin, Petrochemical Complex and Ranoli (in Vadodara district), Naroda, Odhav and Vatva (in Ahmedabad district), Sachin (in Surat district), and Sarigam and Vapi in Valsad district. These estates make Ahmedabad, Bharuch, Vadodara, Valsad and Surat, apart from Kutch, more vulnerable to chemical hazards than other districts. “These districts except Kutch are situated along a north-south alignment, and it is therefore prudent to develop local and regional response capabilities in this geographical region as a priority before other regions”, the report stresses.
Besides, the report states, what would make Gujarat even more vulnerable is if chemical or industrial disaster occurs “as an aftermath of a natural disaster”. For example, Kandla cyclone of 1998 affected oil terminals, jetties, transportation facilities, factories, buildings, warehouses, and storage tanks. There have been reports of chemical spill in Kandla port in the wake of January 26 earthquake in 2001.” Basing their analysis of “vulnerability assessment for MAH, Type-A and Type-B chemical units in the state as per the best available data”, the consultants say, “The proximity to international borders also makes chemical terrorism a possible source of chemical disasters in the state.”
Identifying the type of disasters that are associated with these hazardous units, the report states, the areas are vulnerable to “chemical emergencies are fires, explosions, and toxic releases that affect the population and environment”. It adds, “Additional hazards include chemical spillage or spill over. Chemical corrosion too can cause damage to property and sometimes life. Chemical emergency or disaster can involve one or more of these hazards as described below.”
Pointing out that “fires occur in industry more frequently than explosions and toxic releases”, the report says, “However, the consequences in terms of loss of life are generally less because a fire allows some time for people to escape and physical protection against it may be available. The effects of a fire on people usually take the form of skin burns due to exposure to thermal radiation. The severity of burns depends on the duration of exposure and the intensity of the heat. Heat radiation is inversely proportional to the square of the distance from the source.”
Chemical disasters: The report refers to the type of fire that is possible in chemical industries, saying, “Jet fires occur when a flammable liquid or gas is ignited after its release from a pressurized, punctured vessel or pipe. The pressure of release generates a long flame, which is stable under most conditions. Typically, jet fires have a length less than 50 meters and thus typically stay confined onsite. However, if this jet impinges on a neighbouring tank then that tank ruptures under heat stress. Therefore, it is important to control jet fires to avoid domino effects.”
Then, there is pool fire which “occurs on ignition of an accumulation of liquid as a pool on the ground or on water or another liquid. Pool fire diameters are usually confined to the dyke area of the tank or tank farms. Pool fires can give rise to heat stress under certain conditions. Pool fires in large tank farms can result in a major disaster by a cascading / domino effect.” Pointing towards what may happen in Gujarat, the report draws a parallel with the Indian Oil Corporation (IOC) Jaipur fire of 2009, calling it “an example of a pool fire.”
There is flash fire which “occurs when a cloud of flammable gas and air is ignited. Usually, flash fire or vapour cloud explosion results depending upon the spread of flame post ignition and environmental conditions. In reality, it is difficult to predict whether a flash fire will happen. In a flash fire, within a few second of ignition the flame spreads both upwind and downwind of the ignition source. The duration of this fire is very short, but it can give rise to secondary fires that may take longer to control. A capable fire department should be able to respond to such secondary fires (these are not chemical emergencies but a domino effect).”
Fireballs may occur as “rapid turbulent combustion of fuel, usually in the form of a rising and expanding radiant ball of flame. When a jet fire or pool fire impinges on a vessel containing pressure-liquefied gas, the pressure in the vessel rises and the vessel wall weakens ultimately resulting in catastrophic failure of the vessel. This phenomenon is known as a Boiling Liquid Expanding Vapour Explosion (BLEVE). Although the duration of the heat pulse from a fireball is typically less than 30 seconds, the damage potential is high due to the fireball’s massive surface thermal radiation emissive power. A fireball can also be expected to cause significant overpressures (blast).”
The report states, “Explosions are caused when a mixture of air and fuel gets ignited. Depending upon the characteristics of the explosive vapour, the ignition may also result in a flash fire. The Vapour Cloud Explosion (VCE) can be unconfined or confined. Confined explosions occur within some form of containment (e.g. vessels, pipe work), or in less obvious situations (e.g. between buildings), while unconfined explosions can occur in open air.”
The report warns, “Probably the greatest danger arises from the sudden massive release of flammable material producing a large cloud of flammable and possibly explosive vapour. If this cloud were ignited, the effects would depend on a number of factors including wind speed and the degree of dilution of the cloud with air. It could lead to large number of casualties and damage both onsite and beyond. However, the effects are generally limited to less than 300-400 meters.”
Toxic disaster: Coming to the possibility of toxic disasters, the report states, “Continuous or sudden releases of toxic vapours have the potential to cause death and severe injuries at a much greater distance. In theory, such a release could produce lethal concentrations at several kilometres from the point of release. In practice, the actual number of casualties depends on the meteorological conditions, density of population in the path of the cloud, and the effectiveness of the emergency arrangements. Toxic materials can also be carried considerable distances by water.”
It underlines, “Their release into the public sewerage system, rivers, canals and other water courses, either directly, or through contaminated water used in fire fighting, can result in serious threats to public health. While fire and explosion hazards can be controlled and responded by basic (but capable) fire resource capability. However, response to toxic leaks needs specialist training, equipment, and procedures.”
Environmental impact: Coming to “possible environmental consequences of a chemical emergency include”, the report says these could be:
• The release into the atmosphere of toxic or corrosive gases, aerosols or particulate materials which could ultimately harm the aerial, terrestrial or aquatic environments
• The release of liquids or solids which could adversely affect land or water courses and the flora and fauna therein
• Fires or explosions causing damage to buildings or natural environment
• The effects of environmental impact can be direct or indirect, immediate or delayed, temporary or persistent. The persistent effects are of particular importance, such as damage caused to habitats by fire.
Medical consequence: As for medical consequences or chemical explosion, the report states, “Human exposure to chemical releases can occur through air, food and drink, water or direct dermal contact with the chemical. Epidemiologists need to be aware that apparently inexplicable disease outbreaks may be the first evidence of a toxic release into the community. Chemical-induced disorders can manifest themselves in any organ system. Because the body has only a limited repertoire of disease responses, the signs and symptoms may resemble diseases arising from other causes.”
The report points towards the possibility of following adverse responses to toxic exposures:
1. Effects that are local or arise at the site of contact with the chemical, such as broncho-constriction from respiratory irritants or irritation of the skin and eyes by irritant gases
2. Effects that are systemic or affect organ systems remote from the site of absorption, such as depression of the central nervous system from the absorption of solvents through the skin, or necrosis of the liver from the inhalation of carbon tetrachloride
3. Effects on mental health arising from real or perceived releases, which depend on the psychological stress associated with an incident. The timing of the adverse health effects after exposure may vary. Acute effects appear within seconds or minutes, and include eye irritation, broncho-constriction or pulmonary oedema Sub-chronic effects appear within hours or days, and include delayed pulmonary oedema from phosgene, or renal failure in arsenic poisoning Chronic effects appear weeks to years after exposure. These may be of the greatest concern in an incident, even in the absence of any casualties with acute or sub-chronic effects, and may include cancer and reproductive abnormalities.
The report further warns, “Gujarat has been struck by natural disasters frequently in the recent past. These disasters have impacted industries considerably.” It enumerates them:
• The Kandla cyclone of 1998 affected oil terminals, jetties, transportation facilities, factories, buildings, warehouses, storage tanks, timber industry and, most important, the salt industry.
• There have been reports of chemical spill in Kandla port in the wake of January 26 earthquake in 2001.
• Oil production also suffered since the Hindustan Petroleum shifted its operations from Vizag to Kandla after the event of fire.
The report states, “The impact of these natural disasters could trigger a serious chemical accident in Gujarat, particularly in the port-based industries in coastal area that are vulnerable to earthquakes, tsunamis and flooding.” In this circumstance, the report stresses on the need to “consider resilience against natural disasters while locating and designing the new chemical industry. For existing chemical industries, a retrofitting of infrastructure to remain safe in case of earthquakes and flooding should be prioritized by the industry.”
— Rajiv Shah