In all Residence Districts, the Board of Standards and Appeals may permit potable water pumping stations listed under Use Group IV(B), on sites with a minimum lot area of at least 4,500 square feet, provided that the Board finds that:

1. such use will serve the residential area within which it is proposed to be located; and
2. there are serious difficulties in locating such use in a district where it is permitted as of right and from which it could serve the residential area, that make it necessary to locate such use within a Residence District.

The Board may prescribe appropriate conditions or safeguards to minimize adverse effects on the character of the surrounding area, including requirements that such pumping stations shall be landscaped and surrounded with fences, barriers, or other safety devices.