Abstract. 1 Introduction

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1 Risk assessment study of the mutual interactive influence of working procedures on terminals handling dangerous goods in port of Koper (Slovenia) L. Battelino Water Management Institute, Maritime Engineering Department, 1000 Ljubljana, Slovenia Abstract In the ports all around the world terminals for handling dangerous goods with the same potential threat to the environment and population are as a general rule located together at the same area, if it is possible in larger distance from populated area. So is the case in Port of Koper in Slovenia. In the port a terminal for petroleum derivates and a terminal for liquid chemicals are already existing and in the process is the project for a terminal handling liquefied petroleum gas. For this purpose the risk assessment study of the mutual interactive influence of working procedures on terminals handling liquid chemicals, liquefied petroleum gas (LPG) and petroleum derivates has been elaborated. The study comprises risk analysis of singular influence for each terminal considering exceptional events with probability of occurrence of initial accidents and consequences, then establishment of different possible scenarios and their analysis was prepared. At the end suggestions and recommendations for safety measures regarding all operating procedures were stated. 1 Introduction Port of Koper is situated in the northern part of Adriatic sea between two towns, Koper and Ankaran, which are both touristy oriented. The Port has terminals for various goods, among them also terminals for dangerous goods In future in Koper area a terminal for liquefied petroleum gas (LPG) is planned with the jetty located in the Port of Koper and underground pipeline connection in the length of 3 km to the mounded storage in hinterland The new

2 54 Environmental Problems in Coastal Regions jetty for LPG is planned to be in direct vicinity of terminal and jetty for liquid chemicals and jetty for petroleum derivates. 1.1 Terminal Location The location of the existing jetty for petroleum derivates is on the northern side of the entrance into the basin and the jetty for liquid chemicals together with the terminal with above ground tanks is on the southern side of the entrance. Planned location of the jetty for the LPG is on the front of the pier about 300 m towards west into the aquatorium and 100 m to the north from the ship manoeuvring line into the basin. The connection with the shore is planned to be with an access bridge. Immediately after the bridge reaches the shore there is the heating plant for heating the liquefied petroleum gas from temperature - 42 C to +2 C. This plant is very near to the jetty for petroleum derivates. 1.2 Vessel Number and Characteristics Vessel for LPG - max capacity nr - LOA 140 m - frequency.3 3 per year Vessel for petroleum derivates: DWT -LOA 150m - frequency per year Vessel for liquid chemicals: DWT -LOA 120m - frequency per year 2 Risk Analysis of Singular Influence for Each Terminal Procedures This part is considering exceptional events with probability of occurrence of initial accidents and their consequences. The risk assessment studies for each terminal have been arranged according to the various hazards associated with the transport chain of dangerous goods and with the transfer and storage facilities. The selection of hazard events were made such the studies include the following major hazard situations: * collision or the grounding of the approaching vessel carrying dangerous good or ramming along the jetty ; * rupture of a transfer line and leakage in transfer system ;

Environmental Problems in Coastal Regions 55 * rupture of a storage tank or rail/road tanker (terminal for liquid chemicals) or damage on heating plant (LPG terminal).

3 Environmental Problems in Coastal Regions 55 * rupture of a storage tank or rail/road tanker (terminal for liquid chemicals) or damage on heating plant (LPG terminal). One of the most difficult questions in risk assessment studies is the estimation of the frequencies or probability of possible events or failures. For the establishing estimates of the probability of vessel accidents historical data for oil tanker accidents were used which have been modified with specific location data in Port of Koper. Probability of spills during transfer operations such as leak from unloading arms, seriously leaking flange, valve, pump seals, fracture of rigid pipe etc. have been taken according to FAR (Fatal Accident Rate) So was for the probability of spills during storage. Always the human error was taken into account. After the establishing of identification and probability of spills of dangerous material the possible behaviour of spilled material and the consequences were observed. The final consequences of release of dangerous good can be thermal radiation because of immediate fire and blast wave of vapour cloud explosion which both have effects on surrounding population and constructions. Immediate fire occur when the ignition is present near the leakage, while the vapour cloud explosion is possible, if the spill of material has time to evaporate and mix with the air and disperse If the cloud on its way runs into ignition source it can explode and cause blast wave. In the case when the ignition source is not present, the cloud can gradually disperse in the atmosphere under the weather conditions. It can be dangerous in case of very toxic material. Development of consequences (immediate fire with thermal radiation, explosion of dispersed flammable vapour, dispersion of toxic vapour) of initial accidents has influence on terminal equipment, workers, population and property Here we will present the conclusions and the most important findings of the risk assessment study, such as the absolute physical effects magnitude and individual and group risk to the population. 2.1 Risk Assessment for Maritime Part of LPG Terminal Thermal Radiation The distance of influence of thermal radiation is the greatest for vessel accident. Boundary distance of thermal radiation level equal to 12.5 kw/nf, where the influence to the people is shown as 1% lethality in 1 min and 1* degree burns in 10 s, is for this undesirable event 458 m from the centre of ignition accident. Boundaries of this level of thermal radiation for the other accidents (transfer line, heating plant) are smaller, between 15 and 73 m from the source. The absolute safe distance, where the level of thermal radiation gives no discomfort to the population equal to 1.6 kw/nf is again the greatest for vessel accident, 1000 m while for the other are between 70 and 207 m.

4 56 Environmental Problems in Coastal Regions Vapour Cloud Explosion In the case of delayed ignition and vapour cloud explosion again the greatest impact can be expected after the vessel accident. The boundary limit with the peak overpressure Pa where we can expect 1% eardrum rupture or 1% serious wounds from flying objects as influence to the people and repairable damage to buildings as influence to the property is about 1200 m from ignition centre. For the other accidents the area is inside boundaries 72 to 159 m. The distances with peak overpressure level 1000 Pa, where is no discomfort to the population, are greater. For vessel accident around 8200 m and for the others 500 to 1000m. 2.2 Risk Assessment for Maritime Part of Terminal for Petroleum Derivates Thermal Radiation Also for the maritime part of terminal for petroleum derivates the influence of thermal radiation is the greatest for vessel accident. Boundary distance of thermal radiation level equal to 12.5 kw/rn^ is 116 m from the centre of ignition. Boundaries of this level of thermal radiation for the other accidents on transfer line are very small, around 3 m from the source. The absolute safe distance, 1.6 kw/nf is again the greatest for vessel accident 480 m, while for the other are between 22 and 29 m Vapour Cloud Explosion In the case of delayed ignition and vapour cloud explosion again the greatest impact can be expected after the vessel accident. The boundary limit with the peak overpressure Pa is about 550 m from ignition centre. For the transfer accidents the area is inside boundaries 12 to 19m. The distances with peak overpressure level 1000 Pa are for the vessel accident around 3700 m and for the other 84 to 128 m. 2.3 Risk Assessment for Terminal for Liquid Chemicals For the liquid chemicals we were analysing the whole terminal, maritime part together with the storage area and rail/road trucks filling area, because everything is in the location where mutual interactive effects were observed further on Thermal Radiation Again the distance of influence of thermal radiation is the greatest for vessel accident. Boundary distance of thermal radiation level equal to 12.5 kw/nf, is for this undesirable event 112 m from the centre of ignition accident. Boundaries of this level of thermal radiation for the other accidents (transfer line, storage area, rail/road trucks filling plant) are smaller, between 4 and 12 m from the source. The level of thermal radiation equal to 1.6 kw/m^ is again the

5 Environmental Problems in Coastal Regions 57 greatest for vessel accident, around 390 m, while for the other accidents are between 15 and 80 m Vapour Cloud Explosion In the case of delayed ignition and vapour cloud explosion again the greatest impact can be expected after the vessel accident. The boundary limit with the peak overpressure Pa is about 76 m from ignition centre. For the other accidents the area is inside boundaries 9 to 41 m The distances with peak overpressure level 1000 Pa are for vessel accident around 520 m and for the other 59 to 282 m 2.4 Individual and Group Risk Individual risk with the highest probability (1x10"' - 1x10"*) if we compare all, the thermal radiation and vapour cloud explosion appears in the immediate neighbourhood of the accident and does not have influence on the population outside the industrial area border. The distance >600 m for vessel accident and for transfer accident the distances between 50 and 400 m already give the individual risk probability <lxlo"*, which is lover than 10"* which is generally accepted as acceptable risk averaged the whole population. The tolerable risk for population exposure from the industry is even higher, 10~* to 10"* 3 Possible Scenarios of Mutual Interactive Influence of Working Procedures and their Analysis Any event on any of discussed complex may cause consequential event on the other complexes and further on this can also induce undesirable event backwards In this study we bound to present the influence after the consequences of immediate fire, which is especially important for the discussed location in the Port of Koper Comprehensive study of each scenario shows the most dangerous points, where we have to introduce the most rigorous safety measures and procedures to minimise the risk. 3.1 Fire of LPG Vessel on the Jetty (Scenario No. 1) The LPG jetty is located 100 m to the north from the main access route to the entrance into the basin and around 300 m to the west from the end of pier /Figure I/. After the vessel accident which can happen after collision with another ship coming in or out of the very busy basin or after ramming along the jetty, the immediate fire with boundary level 12.5 kw/m* 458 m /Figure 21 cause threat to the LPG heating plant facilities, to vessel for derivates and liquid chemicals on their jetties and also to storage area for liquid chemicals. From this

6 58 Environmental Problems in Coastal Regions we can see it can induce further accidents of great magnitude. It can induce scenario No. 4 (heating plant), scenario No. 5 (jetty, operating building and transfer pipeline for petroleum derivates), scenario No. 6 (storage tanks for liquid chemicals) and as the greatest scenarios No. 2.2 and 3.2 in the case the vessels for dangerous goods are berthing. The connections between scenarios can be seen from Figure 3. The influence of this scenario is very extensive and from this we can conclude the most rigorous safety measures and procedures has to be introduced during planning, building and operating phase of the maritime part of LPG terminal. 3.2 Fire of Vessel for Derivates Approaching the Basin (Scenario No. 2.1) While vessel for derivates is approaching it has to pass LPG jetty and the LPG vessel if it is berthing there. In the case of accident - collision with another ship, it can cause threat to LPG vessel and induces scenario No. 1. For this reason there safety measures have to be taken for all ships manoeuvring in and out of the basin. 3.3 Fire of Vessel for Derivates on the Jetty (Scenario No. 2.2) Fire of the vessel can be induced by accident during manoeuvring of the vessel or by collision with another ship The immediate fire with boundary level 12.5 kw/rn^ 116 m /Figure 21 cause threat to facilities for transfer of petroleum derivates and to LPG heating plant. Both further on induce events of scenarios No. 4 and 5. We can see the scenario No. 4 (fire during transfer and heating of LPG) can further on has influence on scenario No. 1 and again we are in the circle. 3.4 Fire of Vessel for Liquid Chemicals Approaching the Basin (Scenario No. 3.1) This scenario evaluate all the events from anchoring area to jetty. Because the location of the jetty is more inside the basin (Figure 1), the vessel has to pass by LPG jetty and jetty for derivates. In the case there are vessels berthing and if there comes to the accident this scenario has influence to both and further on causes scenarios No. 2 and Fire of Vessel for Liquid Chemicals on the Jetty (Scenario No. 3.2) Fire of the vessel can be induced by accident during manoeuvring of the vessel or by collision with another ship. The immediate fire with boundary level 12.5 kw/m^ 112 m /Figure 21 cause threat to all the facilities for transfer of liquid chemicals and also the storage area So it induce the undesirable events on the terminal itself (scenario No. 6) and does not mean threat to the other parts.

7 Environmental Problems in Coastal Regions Fire During Transfer of LPG (Scenario No. 4) If there is fire on the jetty, it can induce scenario No. 1, while other parts - heating plant and pipeline means threat to transfer pipeline for derivates (scenario No. 5). From this we can conclude, it would be better not to locate LPG heating plant so close to existing pipeline for derivates. 3.7 Fire of the Unloading Arm for Derivates (Scenario No. 5) In this scenario we analyse all transfer facilities for derivates and find only the accident of the unloading arm on the jetty can have influence on the other parts of the terminals for dangerous goods. This influence has direct threat to vessel for derivates (scenario No. 2.2) and further on indirect threat to LPG heating plant (scenario No. 4) and LPG vessel (scenario No. 1). 3.8 Accident on Terminal for Liquid Chemicals (scenario No. 6) The accident on the each part of the terminal has possible influence and further consequences only on the area of the terminal itself, exception is the accident and fire of unloading facilities on the jetty, where the scenario No. 3.2 can be induced. 4 Conclusions of the Analysis The result of detailed analysis of mutual interactive influences scenarios is that the most risky operations are related to ship transport operations of dangerous goods. Manoeuvring of each vessel can influence on other vessels in the manoeuvring basin and also on the terminal equipment, and mostly on the storage of liquid chemicals. The conclusions of the study are that the most strict safety measures has to be implemented regarding all ship manoeuvring into and out of aquatorium particularly while LPG vessel is berthed on the jetty Beside that special attention has to be dedicated to eventual operations on the LPG jetty and on the jetty for petroleum derivates at the same time. In the case of switching of LPG jetty and LPG heating plant towards north, the safety of all three complexes would increase Also strict safety and risk reducing measures and procedures have to be introduced in all the phases from planning, operating and inspection for all dangerous goods handling terminals.

8 60 Environmental Problems in Coastal Regions j» BAZEN 1 LPG Jetty 2 Jetty for Petroleum Derivates 3 Terminal for Liquid Chemicals Figure 1: Layout

9 Environmental Problems in Coastal Regions 61 KOPEB Figure 2: Thermal Radiation Level 12.5

10 62 Environmental Problems in Coastal Regions Scenario No. 1 - Fire of LPG Vessel on the Jetty Scenario No Fire of Vessel for Derivates Approaching the Basin Scenario No Fire of Vessel for Derivates on the Jetty Basin Scenario No Fire of Vessel for Liquid Chemicals Approaching the Basin Scenario No Fire of Vessel for Liquid Chemicals on the Jetty Scenario No. 4 - Fire During Transfer of LPG Scenario No. 5 - Fire of the Unloading Arm for Derivates Scenario No. 6 - Accident on Terminal for Liquid Chemicals Figure 3: Scenario Interaction

Annexure 2: Rapid Risk Assesment RISK ANALYSIS

Annexure 2: Rapid Risk Assesment RISK ANALYSIS RISK ANALYSIS (I) Catastrophic Rupture of LPG Bullet Truck (18 MT) At the LPG bottling plant, LPG will be transported by Bullet Truck tank. In the event of fire in LPG bullet truck in parking area, BLEVE