Karshi-Khanabad, known by soldiers as K2, was an old Soviet base leased to the United States from the Uzbek government after September 11, 2001 because it was just a few hundred miles from al Qaeda and Taliban targets in northern Afghanistan. However, it is believed by many that served there that K2 was contaminated with chemical weapon remnants from the Soviet War era. Many service members took photographs of themselves next to signs warning of “radiation hazard.” Service members at K2 reported that the pond water glowed green and black goo oozed from the ground. The soldiers stayed in tents in and around this glowing pond. Where the tents were located was at a lower elevation than the surrounding land, so when it rained, it flooded the tent city. Water pushed into the tents ankle-deep and often had an oily, multi-colored sheen.

Veterans have long claimed that exposure to chemicals and/or radiation at K2 have caused them to suffer from an array of otherwise unexplained conditions ranging from chronic fatigue and respiratory conditions to various forms of cancer. At least 61 of the men and women who served at K2 had been diagnosed with cancer or died from the disease, according to a 2015 Army study conducted on the base. However, there is speculation that this number may actually be much higher, because the special operations forces working out of K2 during that time period were likely not considered. Military doctors working at the base started raising concerns about the number of personnel who served at K2 being diagnosed with cancer.