- Search and rescue operations were mainly conducted by local people, due to lack of professional search and rescue teams.
- Lack of communication also prevented health officials from receiving information about the properties of AN and treatment methods of its toxic effects from the expert of the facility.
- The general manager of the facility urgently requested special foam, sprays, pumps, and gas mask filters, which were insufficient in the facility.
- In reply to an external support request, the fire fighting team of the nearby military airport joined the mitigation operations. Fire brigades of nearby municipalities and Istanbul supplied foam and pumps.
- An evacuation order was issued by the crisis center following the pertinent request from the general manager for an evacuation area of 6 km radius around the facility due to the risk to the public health.

27

Acute toxicity symptoms were observed in the emergency response teams and the public living in the vicinity. A number of 27 workers were reported to have been poisoned. One member of the military fighting team reportedly went into a coma, while the other were affected badly. Inhabitants of settlements in the vicinity of the facility suffered symptoms of acute toxicity, such as hoarseness, vertigo, nausea, respiratory problems, skin irritation, headache, eye and nasal irritation (S¸ enocaklı, 2003b; Aydemir, 2010b).

According to Voice of Yalova (2010), there is an alleged increase in the cancer rate due to the event. It was reported that among the 189 people who prosecuted the company after the incident, 17 had died from cancer (Aydemir, 2010a). Among the 5 members of the military fire fighting team, which responded to the spill in the first days of the incident, one reportedly died of lung cancer and another one is treated for it.

- All animals and vegetation died inside the facility within a 200 m radius from the leaking storage tanks.
- 6500 t of AN were released into air, sea and groundwater.
- Measurements conducted at 3 sampling stations close to the facility showed that AN concentration in the seawater was 0.157-2.88 μg/l 10 days after the incident, which decreased to 0.075-0.178 μg/l after 25 days.
- During the first week from the accident, atmospheric AN concentrations of 360 ppm were measured in the vicinity of the pump and 10–30 ppm at other locations within the facility (Supreme Court, 2004).
- Acrylamide, which is a hydrolysis product of AN in the aquatic environment, was also found in the samples (G¨uven and Gezgin, 2005).

A ban was issued by the local government on the agricultural products harvested in the farms around the facility. The farm products were collected and subsequently destroyed. Production losses were reimbursed by the company, which were afterwards compensated by its insurance.

Due to the natural hazard conditions, the local hospitals and clinics were overcrowded with seriously injured people. Hence, they were not able to respond properly to the poisoned people and treat the symptoms adequately.
Electricity was not available and all water pipes, including the ones used for fire fighting, were broken, causing 400 t of water in the water storage tank to flow into the sea.

During the first year of operation, the extracted ground water was treated by an on-site distillation unit and over 80 t of AN were recovered.

Afterwards, the groundwater was treated in the wastewater treatment plant of the facility to recover the low levels of AN, which could not be efficiently recovered by distillation.

The clean-up performance was optimized by continuously altering the groundwater extraction scheme, according to measurements of the AN concentration, groundwater level and rainfall.

At the end of the third year, the AN concentration had decreased from its initial level of > 80,000 mg/l to non-detectable levels and stabilized.

The pump-and-treat operation was continued for five years, resulting in the treatment of 53,000 m3 of groundwater. Monitoring studies were maintained for two more years, until September 2006 (Zanbak, 2006).

-Barriers were constructed to prevent surface run-off of the AN to the sea.
-Following the recovery of electricity after 36 hours, AN was started to be transferred from the containment dikes into intact tanks and the wastewater treatment pond. About 3000 t of AN were reported to have been collected in this way.
-Emergency response activities continued for more than one week until all spilled material was transferred to safe tanks and evaporation was prevented.

- All storage tanks were strengthened against sloshing effects and secondary roofs were constructed to minimize evaporation in case of a leak.
- Hard piping connections to the storage tanks were replaced with flexible connections.
- The ground of the containment dikes was covered with impermeable material and the dikes were reinforced.
- Foaming sprays were installed around the tanks.
- Underground water pipes that were broken during the earthquake were installed over ground.
- The capacity of emergency generators was increased and additional pumps were installed.

- An extensive ground water pump-and-treat system for hydraulic control and product recovery was initiated after the incident.
- Eleven monitoring wells were constructed in order to determine the extent of groundwater pollution.
- Utilizing 5 additionally boreholes, AN concentration, pH, electrical conductivity and ground level measurements were started at 16 locations within the facility area in September 1999.
- Based on monitoring data, two pumping wells were installed inside the damaged tank dike and four French drain-type drainage trenches were gradually put into operation around the tank farm.

Emergency response plans were reviewed and improved by taking natech scenarios into account.