The Board of Standards and Appeals may permit modifications to the bulk regulations for certain  enlargements of public utility facilities set forth in paragraph (a) of this Section, provided that the findings set forth in paragraph (b) are met.

1. The Board may permit enlargements which do not comply with the applicable district bulk regulations for buildings or other structures existing on December 15, 1961, within which any one of the following public utilities is located:
   
   Electric or gas utility substations;
   
   Telephone exchanges or other communications equipment structures;
   
   Water or sewage pumping stations; or
   
   Energy infrastructure equipment.
2. In order to grant such permit, the Board shall find:
   1. that the growth of the utility service demand in the area served by the building or other structure requires such enlargement to house the additional facilities needed to fulfill the demand;
   2. that the network of lines, pipes or other distribution facilities located below the surface of the streets is so integrated with the operations carried on within such building that the provision of such additional facilities at another location would cause substantial duplication of plant and facilities and inconvenience to the public; and
   3. that non-compliance, if any, with the applicable yard or height and setback regulations is the minimum made necessary by essential engineering requirements.

The Board may prescribe appropriate conditions and safeguards to minimize adverse effects on the character of the surrounding area and shall require that the certificate of occupancy shall be limited to such use.