Abstract: Solid waste treatment and disposal is a core course in environmental engineering. In the context of the New Engineering initiative and China's dual-carbon goals, the course should foster higher-order competencies for addressing complex engineering problems, including systems analysis, multi-criteria decision-making, risk control. To tackle slow content renewal, limited hands-on training, fragmented integration of curriculum ideological-political education, and insufficient assessable evidence, this study develops an Outcome-Based Education (OBE) closed-loop quality assurance framework: “course outcomes-learning activities-evidence of learning-attainment diagnosis-continuous improvement” . The course content was reorganized into a progressive “fundamentals-processes-frontiers” structure. We implemented a task-driven blended teaching model incorporating scenario-based ideological-political tasks, and established an experiment/simulation practice chain to enhance design-oriented and integrative training. Using unified item-to-outcome mapping and standardized rubrics, attainment was evaluated via a weighted score-rate method (threshold = 0.60). A historical comparison between the 2020 cohort (pre-reform) and the 2021 cohort (post-reform) shows that attainment for course outcomes 1/2/3 increased from 0.831/0.752/0.780 to 0.887/0.825/0.830, with more than 90% of students meeting the overall attainment threshold. These findings indicate enhanced outcome attainment and provide a replicable reference for similar courses facing safety constraints and high engineering complexity.

Key words: Solid waste treatment and disposal, Outcome-Based Education (OBE), Blended learning, Curriculum ideological-political education, Multi-source assessment, Continuous improvement