What should be used as a baseline data for hazardous site?

Baseline data for a hazardous site should include information on existing environmental conditions, such as soil, water, and air quality, as well as biological and ecological assessments of the area. It should also encompass historical land use, potential contaminant sources, and community health data. This comprehensive baseline helps establish the degree of contamination and informs remediation strategies and risk assessments. Additionally, it serves as a reference point for evaluating the effectiveness of cleanup efforts over time.