I am confused about the usage of と here. I understand it is acting as an adverb, but I don't see why it isn't being used as an adjective. 色々な. Maybe I am translating it wrong? There are many/various procedures.
The difference between 色々と手続きがある/色々な・・・ is only grammatical (色々と[adv.] modifying ある / 色々な[ adj.] modifying 手続き), and I don't see any difference in meaning.
色々と手続きがある can be 'translated' as There are procedures variously, which obviously is not a normal sentence, but I guess many English speakers would understand it as There are various procedures if forced to.
So you can simply think 色々なXがある / 色々とXがある mean the same thing.
A side note is that 色々とある is also possible, without indicating various what. Here 色々な is impossible simply because there is no noun to be modified. The expression is used mostly in conversation, as an answer to Why?. This is used when you want to be vague. The conveyed message is There are many things/reasons, but I don't want to talk about them to you, or I really cannot elaborate on what they are.