An expansion of Rush Presbyterian St. Luke's Hospital was constructed above the Pink Line elevated structure, north of the Polk station. This hospital expansion was constructed above the CTA substation. If one walks along the elevated structure to where it passes under the hospital, one will find the substation.
Viewed from the Pulaski Pink Line station, a short distance north, both the the old and new substation buildings stand. With no need to house rotary converters, the new building to the left can be smaller.