Convert PDF to Word

Clarifications

http://www.google.com/search?q=convert+pdf+to+word+document&rls=com.microsoft:en-ca&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1

Drawings, especially blueprints, are more than likely stored in the PDF document as an IMAGE. You can open the PDF document with a graphics program, make modifications (like add text) and save it as a TIFF or JPG, then insert into a WORD document, but you still can't turn an image into an EDITABLE word document or change the blueprint.

If you want changes to the blueprint, go back to the engineering firm which created the blueprint and pay for those changes. They gave you a PDF document so you could PRINT it, not edit it.

scan/edit the text part of the document.
scan the image part of the document and piece them back together.

I'm sure you already know, but most prints sent out by firms, including architecture/engineering blueprints, are copyrighted, so it's illegal to make changes once you get them. If you really need to make changes or send them to another firm, you'll most likely have to talk to the creating company and get the original files to stay within the law.