June 29 (UPI) -- The U.S. military in South Korea has permanently relocated its headquarters to a base south of Seoul, a move the U.S. Forces Korea commander described as an investment for the long term.
The massive base in Pyeongtaek, Gyeonggi Province, held its opening ceremony on Friday, where Commander Gen. Vincent Brooks called the new base a day that will go down in history.
"This headquarters building within the complex represents a significant investment in the long-term presence of the U.S. forces in Korea. Ladies and gentlemen, this was a project that cost nearly $10.8 billion to build over 10 years," Brooks said before an audience of more than 300 people that included South Korean Defense Minister Song Young-moo.
"[South Korea's] investment was over 90 percent of the cost, and for that 90 percent, the United States remains with you 100 percent."
Construction of the new base, where a total of 43,000 U.S. military personnel and their families are to reside, cost $10.8 billion. At 14.67 million square meters, it is the largest overseas U.S. base.
A South Korean military source told local newspaper Maeil Business the base is in a good place for U.S. deployment, because it is proximal to Osan Air Base and Pyeongtaek Port.
For 73 years, U.S. Forces Korea had used Yongsan, a district in Seoul, as its headquarters.
The area where the military garrison once occupied was returned to South Korea, but work needs to be done, local television network KBS reported Friday.
According to data about the base, acquired through a FOIA request by South Korean activists and lawyers, there were a total of 84 oil spill accidents at Yongsan from 1990 to 2015.
About seven of those incidents involved oil spills of 3.7 tons or more, and 32 cases where at least 400 liters of oil were spilled.
In 2000, the U.S. Eighth Army commander apologized after the military discharged untreated toxic waste into the Han River in Seoul, according to Stars and Stripes.
U.S. Forces Korea has said the army's "number one priority remains ensuring the continued health and safety of our service members, families, civilian workforce, and Korean neighbors."