And you are getting this information as PDF files that are located in a
directory on a server?
If all you want to do is create a connection to those files, you can make a
table with hyperlinks. I assume a survey/record can have several
letters/comments associated with it [a one-to-many relationship], so your
Comments table would have an ID field as primary key, maybe "CommentsID" as
an autonumber field, the record ID of the main table as a foreign key, in
other words, a number field called something like "SurveyID", and a hyperlink
field where you store the location of the files.