Currently, my company is running our website and intranet in CF. We're looking to move our website to PHP, but the intranet must remain in CF for the foreseeable future. Is it possible to run both CF and PHP on the same server? If so what considerations do I need to worry about?

Yes. It's fine. Just install both. I have had them running on my pc and laptop together for over a year.

Yes, should be fine. I run PHP and ASP.NET alongside eachother (using abyss) no problem.

Having converted coldfusion to PHP myself it is certainly possible. Amusingly I still don't actually know coldfusion. Was certainly a fun experience.

Currently, my company is running our website and intranet in CF. We're looking to move our website to PHP, but the intranet must remain in CF for the foreseeable future. Is it possible to run both CF and PHP on the same server? If so what considerations do I need to worry about?

I was able to setup PHP on our test server (which has CF installed and running) and they're working fine sofar.