The facilityId on a Site is the identifier the lead regulatory agency uses in their own database — for example an EPA RCRA facility ID, a state UST program number, or a CERCLA site ID. Storing it on the Site record lets compliance staff cross-reference piper data with agency portals and include the correct identifier on regulatory report cover pages and correspondence without looking it up each time.
Technical section
Data model, API, and internals — visible to developers.