Evaluation of municipal solid waste transportation and cost analysis: case study in Banyuwangi Regency

Population growth in Banyuwangi Regency reached 0.61% BPS Banyuwangi Regency, 2022) with waste generation reaching 1,963,033.98 m3/year. Only 13% of the waste that is transported to the Temporary Disposal Site, TDS (RPJMD, 2021) is generated in Banyuwangi Regency in 2022; its waste generation in 2022 is 5378,2 m3/day with existing transportation using 17 units of dump trucks and 5 units of arm-roll trucks. The aim of this paper is to evaluate the most effective and optimal waste transportation system and estimate vehicle operating costs. The research methods were field studies and interviews with staff, drivers, and waste workers. The main information needed is the distance between the TDS and landfill sites locations, the time between locations, and the operating time of the waste trucks. The results showed that the amount of waste transported daily was 211.89 m3/day with a proportion of 4%. Optimization is carried out by setting aside distances on eight dump truck routes using the nearest-neighbor method with the R algorithm. Based on optimization, the distance reduction achieved by sorting eight dump truck routes reaches 102.95 km. In Banyuwangi Regency, the average daily vehicle operating costs for waste transportation are IDR 625,600 for arm roll trucks and IDR 3,325,200 for dump trucks. The average vehicle operating cost per year for 5 arm-roll trucks and 17 dump trucks reaches IDR 4,277,304,940.


Introduction
Banyuwangi Regency is a district in the East Java Province region that is dominated by residential areas, offices, industry, mountains, and forests.The population of Banyuwangi Regency reached 1,718,462 people in 2021, with a population density of 297 people per square km [1].The increase in population in Banyuwangi Regency reached 0.61%, with waste generation reaching 1,959,659.34m 3 /year.Some of the waste generated was transported to the Material Recovery Facility (MRF), Integrated Temporary Disposal Site (TDS), Unit Waste Bank, Main Waste Bank, and the final disposal site (FDS).The amount of organic and inorganic waste generated every day is 5368.9m 3 /day, and only 211.89 m 3 /day is transported to TDS, or around 4% to FDS.Residents handle waste generation by burning 57%, dumping it into watersheds 6%, throwing it outside without processing it 13%, throwing it into a hole without covering it with soil 6%, and dumping it on the ground and covering it with land 3% (RPJMD, 2021).This situation causes waste to pile up and spread over IOP Publishing doi:10.1088/1755-1315/1263/1/012066 2 several roads, as happened in the Genteng area.Waste transportation is divided into 25 districts, and 24 TDS are available [2].Waste delivery is managed by the Banyuwangi Environmental Service (BES).The landfill is located at Karangbendo landfill, which has been the final landfill since November 2022.The landfill is located in Karangbendo Rogojampi Village.Optimizing the distance of waste transportation is a solution for more efficient and optimal waste transportation services.The availability of facilities and working hours are considered to increase the frequency of waste transportation [3].The addition of the frequency of waste transportation must consider the availability of facilities and working time.Economic evaluation via cost-benefit analysis (CBA) of municipal solid waste is essential to establishing the most appropriate treatment or disposal strategy, and it is often a major concern for solid waste management (SWM) policymakers [4].Optimization of dump routes according to distance and travel time using the VRP (Vehicle Routing Problem) method to get the fastest route.The objectives of this paper were to determine a more efficient route than the previous route, to evaluate the waste transportation system in Banyuwangi Regency, and to recommend improved service for better problem-solving in solid waste transportation in Banyuwangi Regency.
Machine learning algorithms have been applied to all aspects of municipal solid waste management, from waste generation to sorting and transportation, to final treatment and disposal, including generation prediction, waste level detection, route optimization, waste classification, compost maturity estimation, heat value, landfill leachate, monitoring of pollutant emissions, process control, and optimization [5].The nearest neighbor algorithm is a heuristic method for solving VRP.Problems are solved by starting from the starting point and looking for the next point [6].Based on research [7] concerning the effect of the nearest-neighbor method on the efficiency of sending waste trucks in the Mataram City Environment Service area, it resulted in savings of 237 km from the original 919 km to 682 km or a reduction of up to 30%.The total travel time for the waste collection fleet decreased by 315 minutes, or 25%, from the previous 1,517 minutes to 1,202 minutes.In addition to saving the total distance and travel time, the cost of transporting dump trucks is reduced by 50% compared to the original transportation costs.The results of this study indicate that the nearestneighbor method can be used as a recommendation for companies to determine an effective road map.
Another study on the application of the nearest neighbor algorithm for electric vehicles used route optimization in route construction during battery charging.This study is based on battery discharge and distance between cities. Environmental solutions, including battery charging stations, will be presented alongside an energy-efficient road theme for electric vehicles.The simulation results show the accuracy of the algorithm in generating an optimized solution for the EV battery charger routing problem.The nearest neighbour-based algorithm has proven to be productive, dynamic, and economical [8].In subsequent research, the use of the nearest neighbour method was identified as one of the heuristic algorithms, which has proven to be a technique that is successfully applied to many combinatorial optimization problems.The nearest neighbour addition algorithm is an efficient computational method for vehicle route problems.Route problems with vehicle capacity in colleges using bus stops as customer points with a total capacity of 20 customers, the number of vehicles is four.The results of using the method with a total distance of 593,262 and making four different routes [9,10].
In another study, the route of delivery of goods was determined using the nearest neighbour method.The number of routes is the least compared to before using the method, and the total distance using the method is 98610 meters, or 98.61 km, whereas if the route before using the method was 124198 meters, or 124.198 km, then the road reduction is 25588, or 25.588, or 20.6026%.The nearest neighbour heuristic can be used to solve the problem as a basis for determining routes.This method can be used to help identify shipping routes to reduce inventory risk and reduce sales to consumers [11].The nearest neighbour method in waste transportation is represented in Figure 1.

Methods
The first stage of this research was collecting primary and secondary data.In the second stage, the waste was calculated.In the third stage, the analysis of the route of transportation was carried out using the HCS and SCS methods, and then the mileage optimization was carried out using the nearest neighbor method.The fourth stage concluded by calculating the distance and time of waste transportation.In the fifth stage, the Vehicle Operational Cost (VOC) calculation was conducted both in the existing and the plan state.The flowchart of the research method is represented in Figure 2.

Data collection
In the data collection stage (Figure 1), primary data was collected through field observations and direct interviews with staff, drivers, and waste workers associated with the Banyuwangi Environmental Service (BES).These interviews focused on waste transport activities, while the observations involved monitoring work processes in the field, including following vehicles during transportation.Primary data includes service routes, time between locations, demolition duration, and non-productive time.Secondary data was obtained from the BES and includes information on the population served, waste generation, daily volume transported, transportation routes, number and characteristics of vehicles, as well as distance, time, and schedule of waste transportation services.This combination of primary and secondary data supports a comprehensive analysis to formulate the recommendations for improving the waste transportation system.

Waste generation calculation stage
The volume of waste generated per day was calculated based on the number of households served.The volume of transported and un-transported waste was obtained from records carried out by the BES.The data was based on the BES monthly records.The approach method was conducted to calculate the waste generation based on the capacity of the transportation truck.

Data analysis using HCS/SCS method
The calculating of waste transported duration time of existing condition was analyzed using two methods based on the type of truck.The first was Hauled Container System (HCS) for arm roll truck fleets and the second was Stationary Container System (SCS) for dump trucks.The analysis was conducted to determine the total waste transport time per day and the number of trips, in which each truck route of waste transportation per day can be determined.The HCS method apply this formula.

The nearest neighbor method
The optimization route of waste transportation truck is based on the nearest neighbor method which starting from the starting point (TDS) and looking for the next point (FDS).The more efficient route of waste transportation was processed using VRP method and the base data was distance and travel time of truck.

The stage of calculating vehicle operation costs
The cost calculation includes the operational and maintenance costs of the current waste collection system.Costs calculated include costs operations and maintenance, depreciation, insurance, and overhead.

Waste generation
Waste disposal in Banyuwangi Regency is carried out by the BES using three different types of operational trucks, including 17 dump trucks, five arm-roll trucks and one compactor truck.As of November 2022, Karangbendo landfill became a landfill located in two villages, namely Karangbendo and Rogojampi Village.Waste is transported by The BES every day during opening hours from 02:00 a.m. to 09:00 a.m.Each truck has a fixed route with different services area.The location of the TDS/depo that will be transported by each truck has been determined by the BES.This waste truck is separated from the service area of each truck.Waste transportation in Banyuwangi Regency starts between 02:00-04:00 WIB with several different departure times for each route that are adjusted to each route and with the hope of reducing the possibility of arriving at the same landfill and resulting in queues considering the conditions Unloading at the FDS can only be done alternately one by one.
According to the Banyuwangi Regency Environmental Service, the total volume of waste transported is 211.89 m³/day.Data on the amount of waste transported compared to estimated data on population and facility generation reaches 5368.9 m³/day, the proportion of waste transported is 4%.This percentage does not meet the waste management program with the target of implementing waste management in the Regency/City area in 2022 of 13.24% according to the Regional Long-term Development Plan (RPJMD) of Banyuwangi Regency for 2021-2026.

Hauled container system (HCS) waste transportation analysis
Waste transportation in Banyuwangi Regency was carried out every day, both weekdays and weekends in 365 consecutive days per year.Waste transport vehicles apply the Hauled Container System (HCS) system with five units of arm-roll truck vehicles.The object of waste transportation analysis with the HCS system includes 11 containers.The arm roll truck has a route that is different from the specifications of Banyuwangi City and the destination area of the Muncar Beach.The evaluation of the time between and the distance travelled is shown in Table 1.Based on the results of calculations, waste transportation or working hours in service areas were not uniformly regulated.Displayed longer working hours than the P 8372 QP armroll truck transportation because of the service location and longer distance compared to other armroll trucks.This can also lead to suboptimal vehicle operation because the workload of each officer is not balanced.The result of optimizing the evaluation of the HCS transmission pattern is an even distribution of waste from the arm roll trucks; the goal is that each arm roll truck has the same travel load and increases the amount of waste transported.Addition of HCS model source locations at depots or TDS on unserved routes.Estimated mileage with the HCS system is a minimum of 45.3 km/day and a maximum of 146.3 km/day.In Ramadhan et al. ( 2019) research, the uneven distribution of waste transport routes can affect the effective working time of each vehicle driver, and the volume of waste transported between drivers of waste transport vehicles is uneven.

Stationary container system (SCS) evaluation analysis
Waste transportation using the Stationary Container System (SCS) system in Banyuwangi Regency is carried out every day on weekdays and national holidays (Sundays), 365 days a year.Waste transport vehicles using the Stationary Container System (SCS) system with 17 units of dump trucks are the object of analysis for waste transportation using the SCS system, which includes 36 TDS, eight depots, and five markets.Meanwhile, trucks have various routes to provide services in 24 sub-districts in Banyuwangi Regency.The results of evaluation is shown in Table 3.
Table 3.The results of the evaluation of the time between and the distance traveled by the SCS system.Based on the results of calculations on the transportation of dump truck vehicles, data on pool time to the first TDS (t1), time from FDS to pool (t2), off-route time (W), and working hours (H) are used to calculate the number of trips that can be made in one working day (Nd).These calculations show that the average time (PSCS) for a dump truck is 3.79 hours, and the time for each trip (TSCS) is 4.52 hours.The average time for loading waste (UC) is quite high, at 1.46 hours.According to the officer in charge of the dumptruck vehicle, the long waiting time was due to the time it took for the cart to come to the TDS/Depot, which affected the length of processing time.This can result in a fairly high time value when waste is loaded into the dump truck.Off-route time (W), average dump truck speed, and used to calculate the number of trips that can be carried out in one working day (ND), produce the average value of the number of trips (ND) of dump truck vehicles at each Depo/TDS location: 0.87-1.Table 4 shows the evaluation result on ND.

Route optimization
The Banyuwangi Environmental Service (BES) regulates and determines the route for waste transport vehicles during waste transportation operations in Banyuwangi Regency.Based on direct research and observation of transportation route data, the existing conditions of the current waste transportation route were analyzed by eight waste transportation routes for the total distance of waste transportation from the pool (the BES) to FDS (FDS Karangbendo, Rogojampi) using the nearest neighbour method to determine the shortest route that can be passed by each dump truck.The goal is to find a transportation route with the best and most efficient distance and time.The existing route and total distance each truck is listed in Table 5 and the map of existing route is shown in Figure 3.  From the results of the analysis using the nearest neighbour method with the R algorithm with the help of the https://posit.cloud/site, it shows that some of the dump truck vehicle routes have changed the order of the routes taken to reach the FDS service, which are marked with a description of the new route.Route changes are shortened by reducing the total distance of eight existing routes into 462.3km (the route shortened of 105.95 km), while the existing total route distance is 565.25 km.The optimization route is listed in Table 6, and the map of new route is shown in Figure 4.

Vehicle operational costs
Vehicle operating costs are costs that arise financially when the vehicle is used according to its designation.The depreciation value is due to the age of the vehicle, taking into account information on estimated investment costs and depreciation related to the acquisition of transportation equipment (trucks).Operating and maintenance costs include the wages of truck drivers and employees, maintenance, oil, parts purchases incurred annually, and fuel expenses incurred daily.Cost analysis consists of comparison between existing and optimization routes is shown in Table 7.

Conclusion
The existing condition of the waste transportation system in Banyuwangi Regency has 5 units of armroll trucks operating with an average distance of 94.48 km/day and an average travel time of 1.82 hours/day, and 17 units of dump trucks with an average mileage of 45.32 km/day and a travel time of 4.51 hours/day.The existing transported waste generation is 211.89 m3/day (4%) of the estimated waste generation per day of 5368.9 m3/day.The results of route efficiency using the nearest neighbour method with the R algorithm show that the eight updated routes are the most effective and optimal solution in terms of distance, showing a reduction in the existing mileage of 105.95 km on eight routes and 102.95 km on a total of 17 dump truck routes.The cost of transporting waste, which consists of the total operating and maintenance costs and annual maintenance depreciation, is IDR 4,277,304,940.The daily fuel price for transporting waste with five arm-roll trucks is IDR 625,600 and for 17 dump trucks, IDR 3,325,200.The cost of transporting waste per day for the eight optimized truck routes is IDR 2,899,285 per day or IDR 425,915 per day.

Figure 1 .
Figure 1.The stage of the nearest method in waste transportation.

Figure 2 .
Figure 2. The flowchart of research method.

Figure 3 .
Figure 3.The existing route of waste transportation.

Figure 4 .
Figure 4.The optimization of new route of waste transportation.

Table 1 .
The results of the evaluation of the time between and the distance traveled by the HCS system.The results were based on the calculation of distance traveled, transport time per trip Phcs trip, HCS waste hauling time, and the average speed of the number of transportation trips per day on armroll truck transport vehicles in Banyuwangi Regency.The average value of the number of trips (ND) of armroll truck vehicles at each Depo/TDS location is 2.49 (≈ 3 trips) per day, it is shown in Table2.

Table 5 .
Existing route and total distance.

Table 6 .
New route and total distance.

Table 7 .
Comparison of daily operational costs of existing routes and optimization routes.Annual vehicle operating costs are the result of annual calculations of maintenance costs, driver and employee wages, and vehicle depreciation.Based on the results of the evaluation, the total operational costs are IDR 3,110,475,000 in operating and maintenance costs, and vehicle depreciation is Rp.1,166,829,940 per year, so that vehicle operating costs per year become IDR 4,277,304,940.Vehicle operational costs incurred every day are material costs.vehicle fuel with a total daily cost of IDR 625,600 for five arm roll trucks and IDR 3,325,200 per day for 17 dump trucks.