Conducting a Phase I Environmental Site Assessment is the best initial step because former coal manufacturing and mining sites may contain contamination. In LEED, redevelopment of contaminated or potentially contaminated sites supports brownfield redevelopment and helps protect undeveloped land, but the project team must first understand environmental risks. A Phase I Environmental Site Assessment reviews historical uses, records, site observations, and potential recognized environmental conditions. If contamination is suspected, additional investigation such as a Phase II assessment may be needed. A site ecology survey may be useful later, but contamination risk is the critical first concern for a former industrial site. Historic-use research is usually part of the Phase I process. Starting construction immediately is unsafe and inconsistent with responsible site development.