A Mixed-Methods Empirical Juridical-Economic-Logistics Model for Optimising Incentive-Driven Plastic Waste Recovery in the Krui Coastal Tourism Cluster

Background: The Krui coastal tourism cluster has experienced a sharp rise in plastic waste generation, increasing from 0.9 t day⁻^1 in 2016 to 1.2 t day⁻^1 in 2026 (33.3 % CAGR). This escalation threatens marine ecosystems, public health, and the region's tourism attractiveness. Objectives: This study aims to develop an integrated optimisation framework that simultaneously (i) minimises logistical costs of waste collection, (ii) maximises compliance of micro-enterprise operators through behavioural-economic incentives, and (iii) ensures juridical enforceability under the Indonesian Civil Code (KUHPerdata). Methods: A mixed-methods approach was employed. (1) A mixed-integer linear programming (MILP) vehicle-routing model was built using Gurobi 10.0, calibrated with RFID-derived distance, load, and fuel-consumption data from 48 collection trips. The model incorporates load-dependent fuel cost functions (Lestari and Hartono, 2022) and vehicle-type capacity constraints (Putri and Santoso, 2025). (2) A behavioural-economics incentive module estimated compliance probability via a discrete-choice experiment administered to 120 hotel and restaurant managers; logistic regression yielded marginal effects of monetary rewards on compliance (Zhang and Chen, 2024). (3) A doctrinal analysis translated Articles 1243, 1320, 1338, 1244-1245 of the KUHPerdata into a contract template, specifying cure periods, risk-allocation matrices, and mandatory insurance (Wibowo and Prasetyo, 2025). Published in Journal of Coastal Frontiers and Applied Development (JCFAD). CERN Zenodo Record: https://doi.org/10.5281/zenodo.24089643. Publisher: PT CHAIN ASIA CONECT Research and Development Division.