Importing From Excel .csv W/ No Primary Key

There are some web forms where people can submit work requests to my team. The data is fed into Excel in .csv format. Each request adds a new row to the spreadsheet. Nothing ever drops off.

I am having problems getting that data into my "final" Access tables without repeating the data with each subsequent import/append. There is no unique identifier in the Excel file, only the raw data, all fields of which could be duplicate across requests.(requestor, phone, request by date...) In my Access tables, I have the same fields as in the Excel file, along with an AutoNumber primary key and some additional fields where we can enter when work began and was completed and to who it was assigned.

Say for example 5 requests come in and thus create rows 1-5 in the Excel file. I then import the data into a temp table, and then append to my final table. Works. But say an additional 2 requests come in...I then do another import and append and my final table ends up with rows 1-5 AND 1-7.

I was thinking composite key of some sort, but none of the fields lend themselves to that. Plus I need the ability to edit some of the imported data once it hits my final table (ex: changing a request-by date or request detail), so a field by field comparison of the import table to my final table to determine uniqueness probably won't work either.

I'm thinking the solution would be to add a unique identifer at the source level, but I'm pretty much left to come up with a solution in Access as the web team's resources are unavailable for a few months.

Any ideas to get me started???