On-site stormwater disposal systems shall be located at least 5 feet (1524 mm) from all lot lines and 10 feet (3048 mm) from all foundations or walls existing on the date of application for a building permit or proposed under the application to construct the on-site stormwater disposal system. Systems shall be located 20 feet (6096 mm) from disposal fields and 20 feet (6096 mm) from seepage pits. On-site stormwater disposal systems shall not be located within the building footprint .