Dear all,
My project is two underground basement parking floors, that are built on the total land area, while the above-grade floors are built on 30% of the total land area.

Should I consider this project as case -1 (non-zero lot line); accounting for the run-off that may occur on the area outside the above-grade building, or case-2 (zero lot line); as I did practically build 100% of the project area for basements.