One of two mulching machines reduces vegetative debris by approximately 66 percent, one of two machines operating at the Los Alamos Reduction Site in Guaynabo on Dec. 9, 2017. The day was significant in that the U.S. Army Corps of Engineers, with the help of locally-hired contractors, collected its 1 millionth cubic yard of debris on the island of Puerto Rico in the aftermath of hurricanes Irma and Maria. The milestone is significant in that it comes one day after the largest collection day since operations began, with 38, 239 cubic yards of debris collected Dec. 8.