In February 2025, Zeynep Erdem developed the CVM Water Contamination Analysis feature for the dataforgoodfr/13_pollution_eau repository. She engineered a workflow in Python and SQL that loads and merges water quality datasets, focusing on vinyl chloride monomer (CVM) contamination. Leveraging Pandas and DuckDB, she implemented analytics to quantify samples exceeding regulatory thresholds and identify affected communes, supporting public health monitoring and regulatory oversight. The solution emphasized reproducible data integration and threshold-based reporting, with traceability ensured through linked commits. While the work addressed a single feature over one month, it demonstrated depth in data analysis and visualization for environmental risk assessment.