Honestly, pulling all 60 yards seems like overkill to me. Cat spray is bad, no question, but it soaks into the pad and the subfloor way more than the carpet itself, so yanking the berber might not even fix the smell if you don't treat what's under it. There's enzyme cleaners out there that break down the urine at the source, and pros who do ozone or hydroxyl treatments that get into the backing. I've seen guys save carpet that everyone swore was toast, and the homeowner saves a ton of money. Now if it soaked through and sat for weeks, yeah, it's probably done, but just saying "cat peed so the carpet's garbage" skips a lot of steps. Your mileage may vary depending on how long it sat and how much got down in there.