India’s move for exploiting shale gas resources in the country has been red-flagged by The Energy and Research Institute (TERI) stating that in a water-stressed country like ours, rapidly approaching water scarcity conditions, the results might not be as dynamic as it had proved for the U.S.
The latest policy brief “Shale Gas in India: Look Before You Leap” explores the question of shale gas being a game changer in the context of India. It explains the nature of shale gas, the technology for its extraction from underground sources, and its potential for India. It also highlights overseas acquisitions of this resource by Indian companies even before it is sourced domestically, and then examines the viability of the technology in India. One of the key determinants of the viability of this technology is the availability of large quantities of clean water. The policy brief points out that conventional gas can occur by itself or in association with oil. Coal bed methane (CBM), which is extracted from coal beds, is also an unconventional gas and, in terms of depth, occurs much closer to the land surface than other similar gases.
However, shale rock is sometimes found 3,000 metres below the surface. Therefore, after deep vertical drilling, there are techniques to drill horizontally for considerable distances in various directions to extract the gas-rich shale. A mixture of water, chemicals, and sand is then injected into the well at very high pressures (8,000 psi) to create a number of fissures in the rock to release the gas. The process of using water for breaking up the rock is known as ‘hydro-fracturing’ or ‘fracking’. The chemicals help in water and gas flow and tiny particles of sand enter the fissures to keep them open and allow the gas to flow to the surface. This injection has to be done several times over the life of the well.
The number of wells to be drilled for shale gas far exceeds the number of wells required in the case of conventional gas and the land area required is a minimum of 80 to 160 acres.
The other interesting contribution to shale gas development in the U.S. is the export of guar gum from India, which helps in improving the viscosity and flow of water in the fracking process. The gum is extracted from guar ki phalli , grown mainly by farmers in Rajasthan and Haryana. Earlier, guar gum was used mainly as an additive in ice creams and sauces, but with the discovery of its use in shale gas extraction, its production has risen enormously, earning almost $5 billion during the period from April 2012 to January 2013.
The Ministry of Petroleum and Natural Gas (MoPNG) has identified six basins as potentially shale gas bearing. These are Cambay, Assam-Arakan, Gondwana, Krishna-Godavari, Kaveri and the Indo-Gangetic plain. In a study conducted by the United States Geological Survey (USGS), recoverable resources of 6.1 tcf have been estimated in three out of 26 sedimentary basins. India had also put out in 2012, a draft policy for the exploration and exploitation of shale gas, inviting suggestions from the general public, stakeholders, environmentalists, etc.
Water issues
The policy is being considered by a group of ministers. The draft policy has identified some of the water issues in the exploitation of shale gas. Optimal exploitation of shale gas/oil requires horizontal and multilateral wells and multi-stage hydraulic fracturing treatments of stimulate oil and gas production from shale. This may require large volume of water 3-4 million gallons per well (11,000 to 15,000 cubic metres of water required for drilling/hydro fracturing depending upon the well type and shale characteristics).
The water after hydraulic fracturing is flowed back to the surface and may have high content of Total Dissolved Solids (TDS) and other contaminants (typically contains proppant (sand), chemical residue occur in many geologic formation, mainly in shale). The possibility of contamination of aquifier (both surface and subsurface) from hydro-fracturing and fracturing fluid disposal and the need for safeguarding the aquifer is the need of the hour.
The government’s draft policy suggests that there should be a mandatory rainwater harvesting provision in the exploration area, which trivialises the extent to which water will be required. It states, as far as possible, river, rain or non-potable ground water only should be utilised for fracking and re-use/recycling of water should be the preferred method for water management. The environmental concerns in using water for fracking have been considerably downplayed and their significance underestimated. Further, enforcing legislation on environmental and water issues is a problem in India, and such legislation has been more in breach than in observance.
India suffers from physical and economic water scarcity whereas the U.S. and Europe do not have the same water worries. The website Indiawaterportal.org points out that in the next 12-15 years, while the consumption of water will increase by over 50 per cent, the supply will increase by only 5 to 10 per cent, leading to a water scarcity situation.
TERI’s own study in 2010, ‘Looking Back to Think Ahead’, demonstrates that India is already a water-stressed country and is fast approaching the scarcity benchmark of 1,000 m3 per capita with unabated growth in the irrigation sector; again, it is evident that potential shale gas bearing areas, such as Cambay, Gondwana, Krishna-Godavari, and the Indo-Gangetic plains are also areas that will experience severe water stress by 2030.
Shale gas basins
It points out that land acquisition is not covered in the shale gas policy, but will be a serious issue because of the large area required for fracking and the consequent displacement of people. When the government invites bids, they are expected to cover three major basins, i.e., Cambay, Krishna-Godavari, and Raniganj (Damodar basin). According to the Oil and Natural Gas Corporation (ONGC), there are about 34 tcf of shale gas in the Damodar basin alone (compared to India’s total conventional gas reserves of 47 tcf) of which 8 tcf are recoverable.
While the potential shale gas reserves overshadow those of conventional gas, we have a long way to go in identifying shale gas rich basins and acquiring the necessary technology and experience to extract shale gas. Meanwhile, the water situation will only get worse due to the reducing availability of fresh drinking water year by year, dropping groundwater levels, and the increasingly polluted rivers and other water bodies. Unless, there is some revolutionary technological breakthrough, which does not need the use of fresh water and chemicals, it is vital that we seriously ask ourselves this question: Should we further endanger a rapidly depleting resource on which all life depends? The answer should be a resounding “NO”, and instead the focus must be on removing the bottlenecks in CBM exploration and production while safeguarding the environment.
