The Special Development Works (SDW), assisted by the Corps of Engineers, Pakistan Army Corps of Electrical and Mechanical Engineering (PEME), and Frontier Works Organisation (FWO), spearheaded the engineering of the potential sites. The military engineers were well aware of satellite detection, therefore the site at Kharan was constructed with extra cautions. The SDW built around 24 cold test sites, 46 short tunnels, and 35 underground accommodations for troops and command, control and monitoring facilities. The test site was and was L-shaped horizontal shafts. Extensive installations of diagnostic cables, motion sensors, and monitoring stations were established inside the test site. It took nearly 2–3 years for the SDW to prepare and preparations were completed in 1980, before Pakistan acquired the capability to physically develop an atomic bomb.
