This is a bit of a guess. Sometimes, "crowned" can mean to have a slightly rounded top, rather than a top that is flat. Here, the sentence could mean that the footings should be laid/poured with a slightly rounded top that reaches a height of 2 inches above ground level. Grade = ground level.

Hello Gary, in the context, "national identifiers" is a sensitive data item. Does it refer to national identification number or so? As for "defined process", there is "A needs a defined process to destroying ID card or resusing them." Does it mean a process that is already constructed or something like that? Thank you very much for your answer!

Those all sound like they depend on context, particularly as the first two sound like jargon. Can you give some context?