• • BTEX contamination exhibited a localized 'point-source leakage' pattern, with detection rates of 24.3%–47.1% and coefficients of variation (2.32–3.90) confirming high spatial heterogeneity, necessitating high-resolution site investigation rather than grid sampling.
• • Benzene, ethylbenzene, and m/p-xylene exceeded Class I screening values, with benzene posing the highest risk: carcinogenic risk up to 7.42×10⁻⁴ and non-carcinogenic hazard quotient up to 38.24, far above acceptable thresholds (typically 1×10⁻⁶ and 1, respectively).
• • Vapor intrusion was the dominant exposure pathway, contributing over 87% of benzene's total risk, underscoring the need for vapor intrusion mitigation in redevelopment planning.
• • MIP detection revealed that benzene and toluene migrated as a whole, while chlorobenzene exhibited delayed migration due to strong adsorption, indicating that co-contaminant transport models must account for compound-specific retardation.