Supplementary file 1_Diagnosing the structure of policy implementation community in waste sorting: a grounded theory analysis from a China’s case study.docx

As China’s urbanization accelerates, the volume, complexity, and growth rate of municipal solid waste have surged, intensifying the “garbage encirclement” crisis and environmental pressures. The efficient coordination of the policy implementation community (PIC)-defined as a stable relational set of multi-stakeholders undertaking grassroots policy execution-is crucial to the efficacy of garbage sorting. This study diagnoses structural dysfunctions within the PIC that lead to policy idling through a mixed-methods design combining social network analysis (SNA) and grounded theory (GT). Analyzing policy texts from J District, Shanghai, SNA reveals a sparse (density = 0.114), hierarchical network structure with unidirectional information flow and marginalized grassroots actors. GT analysis of 51 in-depth interviews identifies four structural tensions: (1) institutional rigidity under a pressure-driven system results in goal distortion and resource misallocation; (2) fragmented coordination networks cause action blockages; (3) conflicting objectives and a lack of consensus among diverse actors intensify internal friction; (4) short-termism and the lack of debugging mechanisms reduce governance resilience. The integration of SNA and GT demonstrates how these institutional tensions translate into policy effectiveness decay through street-level bureaucrats’ daily practices. This study contributes a micro-level, case-based structural diagnosis of PICs, complementing macro-level policy analysis and offering insights for community co-governance in grassroots environmental governance.