Satellite image of Kharan Desert
|Test site||Kharan Desert|
|Period||30 May 1998|
|Number of tests||1~2|
|Test type||Underground tests|
|Max. yield||40 kilotons of TNT (170 TJ)|
Chagai-II is the name given to the Pakistan's second atomic test, which were carried out on 30 May 1998 in the Kharan Desert in Pakistan's Balochistan Province. Chagai-II took place two days after Pakistan's first nuclear test, Chagai-I, which was carried out on 28 May 1998 in the Ras Koh Hills in Chagai District.
The initial goals were to tests the new designs of the weapon rather than studying the effects and were differed from the first tests as the tests were primary conducted by Pakistan Atomic Energy Commission, with the armed forces' engineering formations having only a supporting role. The single or two device was performed and was a boosted weapon-grade plutonium device as against the first tests that contained only uranium devices. With the performance of the tests made it sum total of six devices having been performed by Pakistan in 1998.
Test preparations 
The weapon-testing laboratories selections and test sites were initiated by PAEC under Munir Ahmad Khan. A mathematical and three-dimensional space survey was commenced by nuclear physicist dr. Ishfaq Ahmad assisted by seismologist dr. Ahsan Mubarak. The PAEC officials met with Prime minister Zulfikar Ali Bhutto to arrange the preparations and decided to bring the role of armed forces to provide supplies and logistical support. After the meeting, Bhutto sent a classified telegram to Brigadier Muhammad Sarfraz, Chief of Staff at the V Corps stationed in Quetta, Balochistan Province of Pakistan.
Brigadier Sarfraz was tasked with the arranging an army helicopter, Mil Mi-17, for civilian scientists from the PAEC; Brigadier Sarfraz was later posted as deputy E-in-C at the Army Combatant Headquarters in Rawalpindi. In 1977, Brigadier Sarfraz was summoned by CMLA and Chief of Army Staff General Zia-ul-Haq and tasked him with creating the special military engineering formations in 1977. The PAEC officials readily agreed that the secondary tests would be scientific in nature with armed forces playing the engineering roles. The Special Development Works (SDW) was given an immediate commission, having the members from military engineering formations, it directly reported to Chief of Army Staff. Its first commander was Brigadier Sarfraz who entrusted with the task of preparing the weapon-testing laboratories and sites. The SDW later elevated as a nuclear variant of the Pakistan Army's famous Frontier Works Organisation (FWO), and commanded by Brigadier Sarfraz since its given commission.
The weapon-testing laboratories at Kharan had consisted of 24 cold test sites, 46 short tunnels and 35 underground accommodations for troops and command, control and monitoring facilities. The site was 300 by 200 feet and was L-shaped horizontal shafts in the testing labs. The weapon-testing laboratories had an array of extensive cables, sensors and monitoring stations. The SDW took 2–3 years to prepare and were completed in 1980, before Pakistan acquired the capability to physically develop an atomic bomb.
The weapon-testing labs were located at Kharan, in a desert valley between the Ras Koh Hills to the north and Siahan Range to the south. Subsequently, the Chagai Hills-Ras Koh-Kharan areas became restricted entry zones and were closed to the public.
After the Brigadie Sarfraz was sent back the Army Headquarters, Lieutenant-General Zahid Ali Akbar Khan was appointed as Engineer-in-Chief of the Pakistan Army Corps of Engineers (PACE) and the Military Engineering Service, as well as the test commander of the Special Works Development (SDW). The modernization of the tests labs were undertaken by Frontier Works Organization (FWO); the FWO uncredited work in the construction of the weapon-testings labs in Kharan Desert, and had supervised the complete construction on the sites along with SDW. The construction was supervised by the Pakistan Army Corps of Engineers's combat engineer then-Lieutenant-Colonel Zulfikar Ali Khan and the Pakistan Atomic Energy Commission under the leadership of Chairman Mr. Munir Ahmad Khan who co-assigned this task to Member (Technical), PAEC, Ishfaq Ahmad.
Test and blast yield 
The tests were conducted and performed on 30 May 30, 1998 at 1310hrs (1:10 p.m.) (PST). The device was a miniaturized boosted-fission weapon-grade plutonium device yielding 60% of the first tests performed two days earlier. The yield of a nuclear device was reported to be 18-20 kt of TNT equivalent. On the other hand, the international observers estimated their calculation based on the results and data their received from their computer and approximating the figure at mere 2Kt. A crater now takes the place of what used to be a small hillock in the rolling desert, marking the ground zero of the nuclear test there. The Pakistan Atomic Energy Commission (or PAEC) had tested one or more plutonium nuclear devices, and the results and data of the devices were successful as it was expected by the Pakistan's mathematicians and seismologists. The devices were successfully tested and supervised by PAEC's Chief Technical Member (CTM) Dr. Samar Mubarakmand.
Cultural legacy 
May 28 has been officially declared as Youm-e-Takbeer (Day of Greatness) and as well as National Science Day in Pakistan to commemorate the first five tests that were carried out in May 28, 1998. The day was officially signed by the then-Prime Minister of Pakistan Nawaz Sharif. The day is celebrated by giving awards (such as Chagai-Medal) to various individuals and industries in the field of science and industries. Government also established the Chagai-I Medal and it was first awarded to the scientists of Pakistan in 1998 who had witnessed the tests. The graphite mountains are visibly shown in the gold medallion and equal ribbon stripes of yellow, red and white.
Preparations and Test Teams 
Pakistan Atomic Energy Commission 
- Samar Mubarakmand, Member (Technical), Pakistan Atomic Energy Commission.
- Muhammad Hafeez Qureshi, Head of Directorate of Technical Development (DTD)
- Irfan Burney, Director of Directorate of Technical Procurement (DTP).
- Tariq Salija, Director of the Radiation and Istope Applications Division (RIAD).
- Muhammad Jameel, Director of Directorate of Science and Engineering Services (DSES)
- Muhammad Arshad, the Chief Scientific Officer (CSO).
- Tasneem Shah, Director of Computational Fluid Dynamics Division, KRL, (CFDD)
Pakistan Army Corps of Engineers 
- Lieutenant General Zulfikar Ali Khan Engineer-in-Chief of the System and Combat Engineering Division of the Pakistan Army Corps of Engineers
See also 
- Azam, Rai Muhammad Saleh (June 2000). "When Mountains Move". Rai Muhammad Saleh Azam. Karachi, Sindh Province of Pakistan: The Nation (1999) and Defence Journal (2000). p. 1. Retrieved 8 May 2012. More than one of
- PAEC Govt. "The Weapon-Testing Laboratories: An illustration by PAEC.". Government of Pakistan release. Retrieved 7 September 2012.
- Carey Sublette (2 January 2002). "Historical Background:§Preparing to Build the Bomb". Carey Sublette of the nuclear weapon archive. Retrieved 2011.
- Rehman, Shahidur, Long Road to Chagai:§The nuclear development under Army: General Zahid Ali, Printwise Publications, Islamabad (1999)
- "Nuclear Tests:§The Plutonium Device". Federation of American Scientists (FAS) and Pakistan Atomic Scientists Foundation (PASF). December 11, 2002. Retrieved 2011.
- "13th Youm-e-Takbeer to be observed today". 28 May 2011. Retrieved 2011.
- "Youm-e-Takbeer being marked today". 28 May 2011. Retrieved 2011.
- "Republic of Pakistan: Chagai-I Medal". 28 May 2011. Retrieved 2011.
- Chagai-II Test on YouTube
- "Comparison of India's and Pakinstan's nuclear tests and the 30 May 1998 Afghanistan earthquake" (php). Broadband Seismic Data Collection Center. Broadband Seismic Data Collection Center, Pakistan Atomic Scientist Federation (PASF), Pakistan Nuclear Society, Pakistan Seismic Department (PAEC), and Pakistan Meteorological Department. 2010-11-23. Retrieved 2011.
- "KNET recording of second Pakistani nuclear test waveforms" (php). Broadband Seismic Data Collection Center. Broadband Seismic Data Collection Center, Pakistan Atomic Scientist Federation (PASF), Pakistan Nuclear Society, Pakistan Seismic Department (PAEC), and Pakistan Meteorological Department. 2010-11-23. Retrieved 2011.