ISLAMABAD — News that the fourth reactor at Pakistan's Khushab nuclear facility is now operational marks the fulfillment of Pakistan's long-term goal to establish a plutonium-based nuclear deterrent.
Mansoor Ahmed, lecturer in the Department of Defence and Strategic Studies at Islamabad's Quaid-e-Azam University, specializes in Pakistan's nuclear program and its delivery systems.
He said operation of the fourth heavy water reactor marked the "fulfillment of [the Pakistan Atomic Energy Commission's] long-standing goal [as per the original plan approved in April 1972] of a plutonium-based weapons program that was conceived and planned by the late chairman, Munir Ahmad Khan."
The program has been developed in phases, but Ahmed says the 2005 Indo-US nuclear deal "aggravated Pakistan's strategic anxieties in terms of huge asymmetries in stockpiles of fissile material, particularly plutonium, that became a driver for the third and fourth production reactor at the Khushab Complex, the second one largely being the product of technological determinism."
News that the fourth reactor is operational comes from a Jan.uary 16 report by the Institute for Science and International Security (ISIS), which analyzed commercial Digital Globe satellite imagery from December 2014 and January 2015.
ISIS's conclusion on the operational status of Khushab 4 is based on a high-resolution image dated Jan.uary 15, 2015, showing steam venting from the cooling system.
ISIS has followed construction of the reactor since it first became aware of it in early 2011. It , and also highlighted that it was generally similar to the second and third reactors built at the complex, but ithas however noticed a number of differences.
In addition to the fourth reactor, three identical additional buildings were also had been constructed that were not built done so for the second and third reactors. There are also Some additional smaller support buildings associated with the fourth reactor were also built.
Vegetation has also been cleared from the area between the first reactor, and the second and third reactors. Whether this has been done intentionally is unknown, but the ISIS report speculates that if it has been cleared intentionally it could indicate preparation for future construction.
There is also new construction activity of an undetermined nature being undertaken at the southwest portion of the complex south of the present reactors, and close to the heavy water production plant.
The report speculates that groundwork for a fifth reactor cannot be ruled out, citing how and bases this assumption on the size and shape of the security perimeter surrounding the construction site , which is similar to that surrounding the second, third and fourth reactors. The visible foundations of the construction work within the new perimeter are also similar to that for the fourth reactor.
However, the new construction is being undertaken close to the southern boundary of this security perimeter closer to the river, and not in the center. The ISIS report concludes therefore that it is too early to determine whether this construction will be a fifth reactor.
Ahmed believes this is unlikely.
"It is unlikely that Pakistan will go for a fifth reactor any time soon. We are already facing indigenous natural uranium ore shortages that limit the number of production reactors that can be operated on indigenous fuel," he said.
Adding, "Natural Uranium ore also has to be prioritized for the production of UF6 [uranium hexafluoride] as feedstock for the gas-centrifuge program--which may or may not have been scaled down or capped."
Public information is not available on the reactors at Khushab, but according to an expert ISIS consulted the first Khushab reactor is likely to have a power capacity of about in the region of 50 megawattsMWth, and the second, third and fourth reactors perhaps having double or greater power output. They will therefore be able to produce twice the amount of plutonium as the first reactor.
AhmedMansoor generally agrees.
"Khushab-1 was designed as a multipurpose research/production reactor that could produce weapons grade plutonium; radioisotopes and tritium simultaneously through normal reactor operations."
However, he believes the assessment that the new reactor is more powerful than the preceding ones is purely based on speculation and photo-interpretation even though any increase in the reactor's thermal output may not be readily apparent from the satellite images.
"The experts' opinion of heavy water reactors seems to suggest that adding heat removal capacity through additional cooling towers in the second, third and fourth Khushab reactors as a means to increase their power and thus the overall plutonium production capacity, is speculative at best", he said.
Adding, "Theoretically, this might be true, as is the in-built design feature of achieving greater power through the use of slightly enriched fuel as opposed to normal natural uranium fuel for such reactor types, but whether or not it is true in Pakistan's case cannot be conclusively ascertained."
Furthermore The capabilities of these reactors has important implications for the type and number of warheads that Pakistan could can produce if it has sufficient stocks of fissile material. , either a larger number of less powerful fission devices, or a smaller number of thermonuclear ones.
"Any one of these heavy water reactors can be partially or wholly dedicated to producing tritium if lithium-6 targets are irradiated in the core, and/or through normal reactor operations of all four of them. As a general rule of thumb, for every 72 kilograms of weapons grade plutonium, 1 kilogram of tritium is produced as a byproduct of heavy water reactor operations. However, only 4-5 grams of this fusion fuel is needed to boost a fission device several times."
Email: uansari@defensenews.com.
Usman Ansari is the Pakistan correspondent for Defense News.
