Eye in the Sky
India, Pakistan and Nuclear Confidence
A water vapour plume from a cooling tower vent at Khushab and the discharge of hot water at Trombay prove that Pakistan and India are producing plutonium for nuclear weapons. Easily available satellite images should be used to make them stop proliferation in South Asia.
Control of the production and use of fissile materials is central to non-proliferation. The main international controls on fissile materials are embodied in the Non-Proliferation Treaty (NPT). The treaty requires all member states (except the five chartered nuclear weapon states, the United States, Russia, the United Kingdom, France and China) to pledge not to manufacture or acquire nuclear weapons and accept "full-scope" International Atomic Energy Agency (IAEA) safeguards. Unfortunately, three de facto nuclear states, Israel, India and Pakistan, have not yet signed the NPT and are believed to be continuing the production of fissile materials for weapons.
The recently concluded 2000 NPT Review Conference urged India and Pakistan to do the following: accede to the NPT and the Comprehensive Test Ban Treaty (CTBT): to maintain the moratorium on testing; observe a moratorium on fissile material production for weapons; and strengthen their non-proliferation export control measures. In a bid to blunt international criticism in the aftermath of their nuclear tests in 1998, both countries have reaffirmed that they will maintain their testing moratorium until the CTBT enters into force. However, recently obtained commercial satellite imagery reveals that both countries are still operating their nuclear facilities and adding to their stocks of fissile materials besides engaging in a missile race. Since the hostility between the two countries magnifies the implications of a regional nuclear race, effective measures at the international level are imperative if this race is to be halted. It is necessary in the first instance to persuade both countries to freeze production of weapon-usable nuclear materials. As a concomitant, the international community needs to create a favorable political environment for arresting nuclear proliferation. This includes resuming the Fissile Material Cut-Off Treaty (FMCT) negotiation and devaluing nuclear weapons possession.
Pakistan's plume
The recent development of high-resolution commercial satellite imagery, especially following the launch of the IKONOS satellite by the US Space Imaging Company on 24 September 1999, provides the opportunity for monitoring the operating status of unsafeguarded nuclear production facilities. This is significant because it could potentially contribute to maintaining nuclear moratoria even in a climate of acute bilateral distrust. The two one-metre resolution IKONOS satellite images of Pakistan's Khushab plutonium production reactor and India's Cirus and Dhruva reactors at Trombay, acquired in February 2000, illustrate the potential of this technique.
The construction of the unsafeguarded Khushab reactor was reportedly completed in 1996. After Pakistan announced that Khushab had started operating in April 1998 its operational status had not been independently verified. Although an analysis on Landsat-7 thermal imagery from July 1999 was conducted, it was unable to establish conclusively if the reactor was operational or not. The new 1m-resolution image shows many more details of the reactor facilities than did the previously released 10m-resolution SPOT image of the same site, acquired on 21 May 1992, which could not resolve the dome, cooling towers and high stack—the characteristic visible features of a reactor.
The IKONOS image clearly shows the reactor's mechanical-draft cooling tower, with a water-vapour plume issuing from at least one of its eight vents. This is a standard cooling tower used to remove heat from the reactor core to prevent a meltdown of the reactor fuel. In the tower, cooling is caused by evaporation from drops of films of water to a flow of air. Air discharged by the towers is usually saturated. A visible water-vapour plume is therefore ordinarily formed when the warm, humid air leaving the tower mixes with colder atmospheric air, leading to super-saturation and condensation of small water droplets. The plume can be quite long when the ambient air is near saturation. A visible water-vapor plume from the cooling tower is evidence that a reactor is in operation.
While it is generally assumed that the warm water-vapour plumes from cooling towers are detectable by thermal infrared (TIR) images, it has been found that using existing commercially available satellite, TIR does not always lead to detection. On the other hand this 1m-resolution image at visible band provides an important way of monitoring nuclear activity by detecting such plumes. Based on the dimension of the resolved cooling tower image, the reactor power is estimated at 50MW, which is sufficient to generate enough plutonium for a few nuclear weapons every year. This particular image provides direct evidence of Pakistan's growing nuclear capability. There is also enough evidence to reasonably surmise that Pakistan has resumed Highly Enriched Uranium (HEU) production at the older Kahuta centrifuge enrichment plant (CEP), despite a declared moratorium on such production since 1991. These two facilities contribute importantly to Pakistan nuclear weapons programme.
India's discharge
The other 1m-resolution image shows the Cirus and Dhruva reactors in Trombay, India. These reactors use natural-uranium fuel and heavy-water moderator. The 40MW Cirus reactor began operation in 1960 and produced the plutonium for the May 1974 nuclear test (Pokharan I. This reactor is currently being refurbished. The 100MW Dhruva reactor commenced operation in 1985. Both reactors produce plutonium for India's nuclear wea-pons and operate without IAEA safeguards.
The once-through cooling system of the reactors can be clearly identified in the image. The cooling water from the bay is drawn through the long structure—the intake channel. The discharged water flows back into the bay in the stream—the discharge channel. While the warmer cooling water is discharged into the estuary through an open channel and mixed with the cooler receiving water, the convection and the flow of the discharge water will lead to localised changes in surface roughness and would disturb normal current flows. It is expected that these changes will be observable in images at visible and near-infrared band (VNIR) through the different hues of the cooling and receiving waters.
As the image shows, the Dhruva research reactor at Trombay (the Cirus reactors is currently shut-down) was discharging hot water into the upper Bombay bay through a stream, confirming that it was operating when the image was acquired in February 2000. India could also be using its unsafeguarded power reactors to increase its plutonium stocks. There has also been talk of building a new plutonium production reactor comparable to the 100MW Dhruva plant.
As these images clearly show, India and Pakistan are operating dedicated reactors to build up their plutonium stocks and it is time for the international community to urge both countries to declare a moratorium on the production of weapon-usable fissile material. Stopping such production will be to the benefit of both countries, which are still recovering from the diplomatic, strategic and economic consequences of their tests in 1998. High-resolution satellite imagery can be of use in maintaining the moratorium.
Under a moratorium, both countries would shut down their major nuclear production facilities, including the reactors at Trombay and Khushab and the CEP at Kahuta. On-site inspections can be avoided, and with it will be dispelled all fears of potential loss of sensitive information about these defence-related nuclear processing sites. Instead, both countries can use the newly available high-resolution commercial satellite images to verify production freeze independently. So long as these reactors remain inoperative there will be no water-vapour plumes from Khushab and no hot water discharge at Trombay. In the event that they are re-operationalised, these reactors require at least several weeks of irradiation to produce a useful concentration of plutonium in reactor fuel. Hence a site-revisit through 1-m resolution commercial satellites once in several days should be adequate to detect an operating plant.
However, there is one caveat that should be entered. According to one estimation, it will be difficult to monitor the operating status of plants like Pakistan's Kahuta CEP by satellite imagery. Because of their small size and relatively low energy intensity, these plants do not require special cooling systems such as the easily visible cooling towers. Also the TIR imaging system on current generation commercial satellites, cannot measure the roof temperature increase associated with their operation. One way around this problem would be to monitor the uranium hexafluoride production facility used for Kahuta CEP. The production of uranium hexafluoride is an energy-intensive chemical and electrochemical process, and may be detectable from the associated heat signatures. Also such activity at these sites as the shipments between the uranium hexafluoride production facility and the CEP site could be monitored by satellite imagery. Hence it will still be possible to monitor the moratorium.
The recent advances in commercial observation satellites can help India and Pakistan build considerable mutual confidence in a declared moratorium by independently obtaining high-resolution satellite images of each other's key nuclear facilities. Both countries can now obtain such images from more than one source. Beside the IKONOS satellite, the Russian firm, Sovinformsputnik has also started providing 1-m ground resolution satellite images.
It is expected that a dozen more of such satellites from several different countries will be in orbit over next few years. Although they are less capable than military imaging satellites, images from commercial satellite are sufficient to monitor the operating status of these production facilities. Unlike classified spy satellite photos, which are limited to a few countries, commercial satellite imagery can be purchased quite freely.
Of course, for such an approach to succeed a favorable political environment must be provided for arresting nuclear proliferation in South Asia. At the international level, the nuclear non-proliferation and disarmament regime should be strengthened. One immediate measure is to resume negotiations on a global Fissile Material Cutoff Treaty (FMCT), which has been deadlocked in Geneva since 1993. In fact, following the appeal by the recent 2000 NPT Review Conference to the Conference on Disarmament (CD) to commence negotiations immediately with a view to reaching an agreement within five years, there has been strong endorsement for prompt negotiations and conclusion of an FMCT by the CD.
Such a treaty, if it materialises, could end the production of fissile material for nuclear weapons, and make irreversible the drawdown of nuclear weapons material in the arsenals of the United State and Russia. It will also cap the size of all potential nuclear arsenals. A universal FMCT would also draw the three de-facto weapons states into the nuclear non- proliferation regime. The FMCT is therefore one key building block in the nuclear disarmament and non-proliferation regime.
To achieve this, the five nuclear weapon states will need to take some practical nuclear disarmament measures to devalue their own nuclear weapons possession. For instance, the United States will have to refrain from going ahead with the national missile defense (NMD) system being pushed by the new administration in Washington DC and its Defence Secretary. The NMD which could damage the whole international arms-control regime and halt progress on nuclear disarmament. Already, because of its concern that the possible deployment of a US NMD system will intensify competition in outer space, China is unwilling to enter FMCT negotiations independent of agreements to prevent an arms race in outer space. (See also commentary, page7) Without China's participation in the FMCT, India will not sign it and Pakistan in turn will not sign it unless India does.
It is also necessary to maintain the Anti-Ballistic Missile (ABM) Treaty, because without it further nuclear disarmament will not be possible. The United States and Russia should de-alert their nuclear missiles and all the five nuclear- weapon states ratify the CTBT, which has becomes the more urgent after the US Senate's rejection of it last year. The United States and Russia will also have to implement START-II and III as soon as possible and commit to deeper cuts in their arsenals to a level comparable to that of the other three nuclear weapon states, which will induce the latter to join in nuclear disarmament.
These are expectations of a huge magnitude and not at all of the kind that can be realised overnight. But there are signs of hope yet. At the 2000 NPT Review Conference, the 187 NPT member states adopted the first-ever consensus Final Document that strongly endorses the treaty and spells out ways to strengthen the non-proliferation regime. The five nuclear weapon states have also unequivocally undertaken "to accomplish the total elimination of their nuclear arsenals" and it is believed that the five nuclear-weapon states have ended their production of plutonium and HEU for weapons. While this process continues at the international level, within South Asia it is important for India and Pakistan to de-escalate their rapidly accelerating nuclear weaponisation programmes. If they have the interest in it, commercial-satellite based monitoring of fissile-material production is now possible.