To find primary sources at CMU (or Prospector or Worldcat libraries) you can add the word sources to your search.
For example: ute and sources
You can also add "type" words to your search, for primary sources of different types.
For example: ranch life and personal narratives.
Words that describe primary source types include:
To find government reports, include the agency name in your search, for example forest service and uncompahgre.
To find environmental impact statements, include that phrase with a location keyword, for example environmental impact statement and uinta.