Camp Leach was the name the U.S. military used for the segment of the Washington, DC main campus of American University during World War I and World War II. The site is now in Spring Valley. During both wars, the university allowed the U.S. military to use parts of its grounds for weapons development and testing. In 1917, 24 days after the United Statesdeclared war on Germany, the university offered its property to the war effort. The military divided the campus into two segments, Camp American University and Camp Leach. The two camps were considered at the time to be "the largest laboratory this side of the sun or other burning stars." Thus, during World War I, Camp American University and Camp Leach became the birthplace of the United States' chemical weapons program. About 100,000 soldiers and 2,000 chemists were employed on the campus. What is now Spring Valley was an undeveloped area on the main campus of American University where the Army was allowed to use for testing chemical weapons, such as mustard gas, therefore also known as the American University Experimental Station or Camp Leach. At the far corner of the university, the military also tested some of its weapons. When the war had ended it was reported that $800,000 worth of World War I munitions were buried in a pit in the same corner of the university.
A decade later, in 2003 many more dangerous sites in the area were uncovered, including perchlorate in groundwater and three burial pits on grounds of the South Korean ambassador's residence. In 2005 ATSDR issued a "Health Consultation"' and 2 years later Johns Hopkins University was contracted for a health study, and reported in 2007. A review of all site data and previous health studies was supposed to be completed by 2013. As of 2017, the work is still ongoing with tons of earth being replaced and at least one house being scheduled for demolition. The site, which included a corner of the university and several neighboring residences, including the residence of the Embassy of South Korea, which occupies a significant percentage of the site. As no buildings have been built directly atop the site, the military announced that the effects of neither the residual chemicals nor the cleanup program will have any effects on students living on the campus. A Restoration Advisory Board is in place. The U.S. Army Corps of Engineers is the lead agency in clean up.