Probably could have used "collection points" rather than "dumpsters" in the article. "Dumpster" seems rather cold and off-putting.
"Volunteers are asked to only remove Wreaths Across America wreaths, no other decorations, from the headstones. Dumpsters will be positioned throughout the cemetery to deposit the wreaths."
https://wtop.com/arlington/2019/01/arlington-national-cemetery-seeks-volunteers-to-remove-holiday-wreaths/