Can I convert a US Topo from GeoPDF to GeoTIFF format?
Yes, it is possible to convert GeoPDF to GeoTIFF using both commercial and open source software. Two methods for separating US Topo layers and reformatting as GeoTIFF are documented in a paper. This paper is revised at irregular intervals; interested users are encouraged to check the link in this FAQ occasionally for updates.
Some additional information, mostly about reformating with commercial graphic art software, is in the US Topo and Historical Topographic Map Users Guide.
As of April 2015, the National Geologic Map Database project's TopoView application serves GeoTIFF versions of maps in the Historical Topographic Map Collection (HTMC). At this writing, the GeoTIFF versions are not served through other applications, nor are they yet available for bulk delivery.
USGS has no plans to create standard GeoTIFF versions of US Topo maps, as the multi-layer nature of US Topo does not lend itself to a single, simple TIFF product.