The Rainier Cemetery District provides us interment listings for twelve cemeteries located in Columbia County, Oregon.
From the landing page, locate the link "Search a Database" located in the left pane of the web page. That will take you to several links you can follow to finally land on an alphabetized PDF file. The information you can find includes name, grave location, and dates of birth, death, and burial. There are also indicators if the deceased had military affiliation.
The landing page has links to the individual cemeteries where you can find photos and maps.