Union Carbide location in Niagara Falls

I'm trying to locate where the UC plant was at 47th St. Some places I read refer to the twin stacks, visible here:
https://goo.gl/maps/g7SxbrdwAG32

and was on the east side of 47th.

Others says Praxair is the former UC plant, which is the west side. Others say Niacet is the former UC plant. See above map.

I'm looking for the plant that had the UCC switchers roaming around in it. Thanks.

How long ago are you talking about? Historicaerials.com has photos from 1972, 1995, and 2002 among others. What was on the east side of 47th in 1972 almost completely changed by 1995/2002, for example

I don't care about the time period other than before a certain date UC was not built and after a date, it was gone.

That whole area around 47th is filled with building. Some were UC and some were other companies.

I'm hoping someone here worked there and may know. Topos won't help as they are not labeled.

I assume you are talking about the chemical plant, not the UCC metals plant? Praxair did buy out the Linde Division of UCC, many years ago.

Yes, but eventually I'd like to ID each company around that intersection, not from a present perspective but historical.