All of the Brownsville graves, including Mexican War, Civil War, and postwar USCT, were moved to the national cemetery at Pineville, Louisiana, just across the Red River from Alexandria. It's a sweet little cemetery that also includes the prisoners who died at Camp Ford and three WW2 German prisoners from Camp Fannin, just down US271 from the Camp Ford site near Tyler.

http://www.cem.va.gov/cems/nchp/alexandriala.asp

However, I don't see Peter Sanders in the Nationwide Gravesite Locator for Alexandria, La. He may be one of the unknowns--there are many there, particularly among the bodies moved from other sites.

Vicki Betts