A brownfield site refers to previously used or industrial land that may be contaminated but has the potential for redevelopment. In cybersecurity and IT, these sites are often repurposed for building new data centers or other technological infrastructure. Redeveloping brownfield sites can be cost-effective and environmentally beneficial, as it makes use of existing resources and locations instead of developing new, undeveloped land (known as greenfield sites). However, redeveloping brownfield sites may require addressing legacy issues such as pollution, outdated facilities, or security vulnerabilities. In the context of cybersecurity, special attention must be paid to physical and digital security risks that could arise from the site's previous use.