A Methodological Approach to Selecting a Location for a Waste Disposal Terminal for Vessels on the Section of the Pan-European Waterway Corridor VII in the Republic of Serbia

The section of the Pan-European Corridor VII waterway flowing through Serbia is of exceptional international significance, as well as significance to the Republic of Serbia, both in the domains of transport and of environmental protection. In this part of the Pan-European Corridor VII waterway, there is development of both passenger and freight traffic without an established system of control and management of solid waste and wastewater from vessels, which directly threatens the environment, as well as the safety of traffic and people. The crews of international and domestic vessels are faced with the problem of disposing of solid waste, waste oil and waste water, due to the lack of adequate waste terminals in this section of waterway corridor VII (The Danube River). For this reason, the construction of a waste terminal is a priority and an unavoidable necessity as a starting point for establishing a sustainable system of managing waste from vessels in the Republic of Serbia. This paper presents a methodological approach for selecting an optimal location for the construction of such a terminal in the city of Belgrade, capital of Serbia (a case study). The method of multi-criteria evaluation of potential locations was used, as well as the method of evaluating various locations under different scenarios. The specificity of the method used can be seen in the selection of criteria for comparative evaluation of the potential locations, as well as in the evaluation of the potential sites under different scenarios and with weight categories based on the PROMETHEE method. The results presented in this paper make it possible for decision makers to consider different aspects and scenarios when selecting the most appropriate location for the terminal, whilst taking into account the international standards and principles governing this field in the European Union.


Introduction
On its way from the Black Forest in Germany to the Black Sea, the Danube is 2,845 km long and it connects ten countries (Austria, Bulgaria, Croatia, Hungary, Moldova, Germany, Romania, Serbia, Slovakia and Ukraine), making it one of the most important European waterways.The flow of the Danube through Serbia is 588 km long, of which 137 km is a section shared between Serbia and Croatia and 229 km is a section shared between Serbia and Romania.The Danube is categorized as an international waterway by the Convention on the regime of Navigation on the Danube River (Official Gazette of the FPRY, no.8/49, Official Gazette of the FRY, International Agreements, no.6/98).As Corridor VII it is an important route, especially after the opening of the Rhine-Main-Danube waterway (1992).The Danube connects the Black Sea with the industrial centers of Western Europe and the port of Rotterdam.
With the intensification of the development of international navigation and navigation in the Republic of Serbia over recent years, issues related to environmental protection when using waterways have become more and more prominent.In this context, effective mechanisms for the collection and disposal of waste generated by vessels are particularly important.However, although from the Co-WANDA report from 2014 it can be seen that in Romania, Croatia, Hungary, Slovakia and Austria, these mechanisms have already been established (Figure 1 terminal network for the collection of waste from vessels in the countries through which the Danube flows), in Serbia no system of managing waste from vessels has been established.As a consequence, the Danube and its n the erials from vessels, the results of which were used in order to make a decision on the most suitable location.

Methodological Framework
The subject of this paper is the application of the Multi-criteria Evaluation (MCE) method (Josimović et al, 2015) in the selection of a location for a terminal for the disposal and treatment of waste from boats.The MCE method, developed in the early 1970s, is now considered a well-developed scientific field, supported by abundant references (Ananda and Heralth, 2009;Figueira et al., 2005;Kangas and Kangas, 2005).When first developed, MCE was characterised by the methodological principle of multi-criteria decision-making (MCDM) with little or no participatory mechanisms included (Zionts, 1979;Zionts and Wallenius, 1976).The primary objective was to elicit clear preferences from a decision maker and then solve a well-structured problem by means of mathematical algorithms (e.g., to design an engine taking into account its power, weight, and efficiency).
Progressively, the ideas of procedural rationality (Simon, 1976) and the constructive or creative approach (Roy, 1985) led to the development of the multi-criteria decision aid (MCDA), in which the quality of the decision-making process became central.Research started to point out the need to include public participation in MCE (Banville et al., 1998;De Marchi et al., 2000;Proctor, 2004), thus fostering the emergence of participatory multi-criteria evaluation (PMCE) (Banville et al., 1998;Proctor and Drechsler, 2006) and social multi-criteria evaluation (SMCE) (Munda, 2005(Munda, , 2008)).In such a context, appropriate deliberation is a prerequisite to ensuring a quality outcome.Nowadays, the MCE method is often recommended as a convenient support in the decision-making process because of its capacity to point out in many ways multiple alternatives of development on the basis of assessing criteria related to the environment and socioeconomic aspects of sustainable development.
In the context of the methodological approach of the multi-criteria evaluation of potential locations for a terminal for waste from vessels, or the selection of any location for waste materials, two procedures are applied: 1. simple addition of the values obtained for a potential location in relation to the defined evaluation criteria and 2. multiplication of the values obtained with the importance values (weight values).
The first steps in evaluating potential locations is the easiest, and it has very few requirements.By simply adding the score obtained for each individual criterion, the most favorable score is obtained.The assessment of locations in this case does not have different scenarios that could be of great help to decision makers.
The other procedure is more complicated and different scenarios can be used in it.For example, if the criteria for locating the terminal are classified into a number of groups, then the same number of scenarios are considered as there are groups of criteria.In the first scenario, the criteria from one group are favoured as the most important, in the second scenario the most important criteria are from another group, and so on.As the last option, the situation is considered in which the groups of criteria are multiplied by the same score of importance, without favouring any individual of the groups of criteria.By presenting the different scenarios in a synthesis table it becomes easy to see which locations for which scenarios are the most favorable.An example of this type of approach is the PROMETHEE (Preference Ranking Organisation Method for Enrichment Evaluation) method (Brans, Vincke, 1984).The primary advantage of this approach is that it gives decision makers a clear idea about which potential location is the most favorable if the criteria from one particular group are evaluated as the most important (environmental or economic or spatial etc.), and which is the most favorable if the basic groups of criteria are treated equally.The application of the different scenarios is based on the PROMETHEE method (Behzadiana et al, 2010).
A combination of these methodological approaches provides the decision makers with more options on the basis of which it is possible to make an optimal decision, which was the case in the specific example of selecting a location for a terminal for waste from vessels in Belgrade.

Case study: Selecting the Location for a Terminal for Waste from Vessels in Belgrade, the Capital of Serbia
The choice of location for the construction of a terminal for waste from vessels in the city of Belgrade, the capital of Serbia, was carried out in two phases: phase I -identifying potential locations suitable for the terminal, and phase II -multi-criteria evaluation of the potential locations for the terminal.

Identification of Macro Locations Potentially Suitable for the Terminal
Identifying potential locations involved selecting a certain number of locations that meet the basic preconditions for the terminal, and those are: PL4 is the only one of the nominated locations that is situated on the Sava River, in the municipality of New Belgrade (Figure 2).As with the previous three nominated sites, this one is also envisaged by the GUP Belgrade to be for municipal services.PL 4 has an unbuilt area of approximately 45 acres.On one side of this potential location is the New Belgrade district heating complex, and on the other side is the New Belgrade block 70a.At this location there are no bank revetments, and there is no mooring for vessels.
Below is a detailed comparative multi-criteria evaluation of the potential locations, primarily in terms of the defined capacity of the terminal and the economic feasibility of the necessary interventions in the area, with consideration of all of the other implications (strategic, social, environmental, etc.).It was inevitable that all relevant institutions and decision makers would be included in this process, in order to select the location for the terminal as soon as possible and avoid any potential spatial conflict.

Multi-Criteria Evaluation of Potential Locations for the Terminal
This Phase II involves the use of the method of comparative multi-criteria evaluation of the potential locations carried out by means of a few basic steps:  defining the criteria for the evaluation of potential locations,  determining the weight factors and grouping the criteria into weight categories,  multi-criteria evaluation of potential locations according to the weight categories,  evaluation of the potential locations according to different scenarios.

Defining the Criteria for Evaluating the Potential Locations
Defining the criteria for determining the location of the terminal is an important methodological step.In practice, two basic groups of criteria are most commonly used.
The first group is that of the elimination criteria which are used in the initial phase of the process of selecting the location for the terminal.The elimination criteria are defined in relation to the actual situation, represented by the restriction criteria.Some of the elimination criteria can be: the planned use of the space, distance from the natural elements of the space, distance from the anthropogenic elements of the space (infrastructure, settlements, protected cultural objects, etc.), and so on.The areas that do not need to be analyzed further are distinguished according to the elimination criteria.For the elimination phase, a single criterion method is generally used, which was the case here.Namely, the elimination criterion in this particular case was "planning documents defining the appropriate use of the land" (in this case for public utilities), together with the fact that all other possible elimination criteria were taken into account in the preparation of the planning/urban planning document that defined such a purpose.
The other group of criteria includes those on the basis of which evaluation of the potential locations will be carried out in an equal manner.The criteria for evaluating the locations can be classified into several groups.These are usually sets of criteria that cover the different implications of the planned project on the environment, and they are:  ecological or environmental criteria,  socio-economic, social or spatial criteria, and  technical and operational criteria (which usually contain certain economic, spatial and environmental criteria).
Any variation of the group of basic indicators is possible.After selecting the relevant criteria, a particularly sensitive and important step in the process of site selection is to define the value of the scale on the basis of which individual criteria are assessed (evaluated, scored).Each criterion is given a corresponding weighted value which is determined on the basis of expert assessment and the evaluation of participants in the process of selecting a location for the terminal.It is usual to use a system of quantitative assessment (e.g.scores ranging from 1 to 5 or from 1 to 3).
The defined criteria (Table 1) in relation to which evaluation of the potential locations for constructing the terminal for waste from vessels in Belgrade was carried out, were based on:  requirements and recommendations of international and national documents in this field,  research and analysis of the practical experiences of other countries and recommendations of the EU, and the availability of relevant data for evaluation,  existing planning/urban documentation,  predictions made regarding the types and quantities of ship-generated waste, that is, the required area for constructing the terminal,  data and information collected during visits to potential sites,  information available on the potential locations, and others.It is possible to classify additional criteria in addition to the above, which could also be used to evaluate potential locations for the future construction of a terminal for boat waste (hydro-geological, geotechnical, geomechanical, etc.).However, the selection of criteria was based only on the data available on the locations, in order for the results obtained from the the evaluation to be objective.In this case, selection carried out in this way proved to be adequate.As shown, each criterion is evaluated with a score of 1 to 3 for each potential location.

Determination of the Weight Factors and Grouping of Criteria into Weight Categories
After selecting the relevant criteria and defining the value scale for each criterion (scores from 1 to 3), the criteria were given appropriate weighted values.The criteria were classified according to their importance into 3 weight categories (WC).Each WC has its own specific value -the weight that is multiplied by the value of the criterion it belongs to.In this way a final score is obtained for each criterion.The specific values for the weight categories are: Between the weight categories, the following applies: K i+1 = K i /1.5  The principle of multi-criteria evaluation of the potential locations according to weight categories is presented in Table 3.
Table 3. Evaluation of the potential locations (PL) according to the chosen criteria Space available for locating the terminal WC 3 9 9 9 9 2.
Distance of the location from the waterway WC 3 6 6 9 6 3.
Distance of the location along the waterway from an international port for cargo traffic WC 3 3 3 9 3 4. Distance of the location along the waterway from an international port for tourist traffic WC 3 3 3 6 3 5.The presence of bank revetments and moorings WC 3 3 3 6 3 6.
Linear distance from the nearest access road WC 2 4. The scores of the criteria (1-3) were multiplied with the specific values for each of the 15 criteria, and in that way the values were obtained that are presented in Table 3. Simply by adding the values for each criterion, a total score was obtained for each potential location.As a result of the evaluation of the locations according to weight categories, the most favorable location was seen to be PL3, after which the locations were in the following order: PL4, PL1 and in last place PL2.The most important advantages of PL3 (the Port of Belgrade) over the other potential locations are:  Proximity of the location to an international port for cargo traffic,  Proximity of the location to an international port for tourist traffic,  The presence of bank revetments,  The relief of the terrain,  arrangement of the terrain,  existing infrastructural facilities.

Evaluation of the Potential Sites Under Different Scenarios
When evaluating the potential locations under different scenarios, based on the PROMETHEE method, the criteria chosen for selecting the location were sorted into primary groups, and in the evaluation, for each individual scenario criteria from one of the primary groups were favored.As the final option, the case was considered in which the groups of criteria were multiplied by the same score of importance, without favoring any particular group of criteria.This scenario has as many criteria as the other groups, plus one for the scenario in which each group of basic criteria is evaluated equally.
The chosen criteria for evaluating the potential locations of the terminal for waste from vessels in Belgrade under different scenarios were classified into three main groups (Table 4).Distance of the location along the waterway from an international port for cargo traffic 16.Sanitary protection zone for the water supply 4.
Distance of the location along the waterway from an international port for tourist traffic 5.The presence of bank revetments and moorings 8.
Linear distance from the nearest access road 9.
Service (access road) -construction 10.Existing infrastructure at the location 14.Market value of the undeveloped construction land at the location The score of each individual criterion from the primary evaluation is multiplied by the weight values for the groups of criteria according to different scenarios.The weight values in this case are percentage values, the total sum of which is 100%, with the largest percentage value given to the group of criteria favored in the given scenario (Table 5).
Table 5.The weight values for the primary groups of criteria in scenarios After multiplying the values of the criteria from the primary evaluation with the weighted criteria according to the different scenarios and their simple sum, ranking was obtained for the locations for the terminal for waste from vessels according to the different scenarios (Tables 6).
Table 6.R Multi-criteria evaluation of all of the scenarios confirmed the results obtained by evaluating the potential locations according to the chosen criteria and weight categories.Thus, location PL3 showed the best values according to each of the scenarios.Location PL4 takes second place for all of the categories, while the remaining potential locations take different positions depending on the scenario.

Recapitulation of the Evaluation Indicating the Best Locations
On the basis of the comparative multi-criteria evaluation of the potential locations, the most important advantages and disadvantages of the candidate locations were identified (Table 8).• Large distance from the international port for cargo traffic (about 9km) • Large distance from the international port for tourist traffic (about 5km) • There are no revetments or moorings • High market value of the construction land • Proximity to residential buildings • Located in the narrow zone of protection for water supply sources.
To sum up the results of the evaluation, it was concluded that all of the locations have certain advantages and disadvantages (Table 8), and that none of the potential locations for the construction of a terminal for waste from vessels in Belgrade are ideal as they do not meet all of the necessary requirements.However, in all of the presented variants and evaluation scenarios, potential location PL3 (Port of Belgrade) had the best results compared to the three other potential locations, so in this context it can be concluded that it is the most favorable for the location and construction of a terminal for waste materials from vessels. eer.ccsenet.
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The -Criteria Evaluation of the Potential Locations According to the Weight Categories value of the undeveloped construction land at the location WC Total sum of the values of the individual criteria 51.0 49.5 75.5 56.5

Table 1 .
Criteria for selecting a location for the terminal for waste from vessels in Belgrade

Table 2 .
Grouping the criteria according to weight categories (WC)

Table 4 .
Classification of the chosen criteria in the basic groups of criteria

Table 8 .
The most important advantages and disadvantages of the potential locations Danubian Serbia", TR36016, financed by the Ministry of Education, Science and Technological Development of the Republic of Serbia in 2011-2016.