Do you know how much cascade and columbus hops you have (in grams or ounces)? Depending on how much Columbus, you should be able to keep the 60 minute addition, but drop the 45 and 30 minute additions and add those in with the 15 and 5 minute additions or even 5 and 0 minute additions. That will reduce the IBUs and increase the hop flavor (15 & 5 = more flavor) and even aroma (5 and 0 = more aroma) by a bit.
It doesn't list what the grain amounts or OG will be, but I'd guess this would be at the low end for an IPA which is ok for a Pale Ale. If you want to reduce you could leave some base malt out (if the grain is separated). I'd probably just leave it all in there.