On February 15, 2017, India’s central government announced the award of contract for development and extraction of hydrocarbons from 44 contract areas nationwide, including 28 on-land fields and 16 offshore. Within a day of the announcement, protests broke out in Neduvasal, a little known village in Pudukottai district in southern Tamil Nadu.
The Neduvasal oil field had been awarded to Karnataka-based Gem Laboratories. Less than two weeks following the announcement, the agitation has gathered steam, feeding off the young energy from the recently concluded protests against the ban on jallikattu. Proponents of the project have questioned the credentials and intelligence of the protestors. Union minister of state for shipping, road transport and highways Pon Radhakrishnan has appealed to the people not to oppose the project blindly. “Are all of them scientists who know enough to oppose the project?” he asked.
The people of the villages in and around Neduvasal are not aware of the project’s specifics. However, interactions with protestors suggest that what they know in general about oil exploration and production, and about the track record of ongoing oil production operations in Nagapattinam, Tiruvarur and Thanjavur districts, is robust enough to form an opinion on the desirability of the project.
The region’s farmers fear that hydrocarbon extraction will disturb the comfortable agrarian economy extant in this region. Neduvasal is located in an area rich in groundwater and blessed with the fertile soil of the delta. Unlike the lower reaches of the delta, where agriculture is in distress, Neduvasal still has a healthy multi-crop farm economy.
The issues raised by the protestors are worth engaging with. Rather than allowing every protest to degrade into name-calling, where protestors are branded ignorant, anti-national, misled or foreign-funded, it may be worthwhile to engage with substantive issues raised by them. To this end, the following is an FAQ on the subject.
The people of Neduvasal are blindly opposing the project. How can they oppose it without knowing the specifics of the project, especially when ONGC has been successfully extracting hydrocarbons in the delta region for decades without protest?
While specific information may not be available, villagers are aware about the general consequences of hydrocarbon extraction thanks to a successful and popular campaign against a controversial coal-bed methane (CBM) project in Thanjavur between 2010 and 2016. Led by the late G. Nammalwar, a popular organic farming proponent, the campaign included a massive awareness drive to educate villagers about CBM as well as about how hydrocarbons are extracted from Earth, the effects of such operations on the environment and on people’s livelihoods.
An exploratory well constructed by ONGC near Neduvasal in 2008-2009 also gave villagers a sense of things to come. “For three months after the well was dug, they would burn the gas night and day. Sometimes the gas would burn orange with black smoke, and sometimes blue with no smoke,” says T. Amudha, an engineering graduate who gave up her job in Chennai after being disillusioned by city life to return to farm in her village. Pointing to a pit filled with oily wastes, she says, “Look at that. That has been lying there for seven years. If there are heavy rains, the wastes flow out of the pond into the neighbouring lands. This is only a small quantity, generated during the exploration stage. Much larger quantities will be generated during oil production.”
“With this in front of me, how am I to believe that they will behave responsibly?” she asks.
Within 100 km from Neduvasal, ONGC operates about two-hundred oil wells and a score of other installations. ONGC’s track record of operating these wells is bad. In 2010, 2011 and 2012, crude oil leaked from underground pipelines running through people’s fields in Nagapattinam and damaged standing crops, irrigation canals and contaminated groundwater.
K. Dhanapalan, a farmer and activist with the Cauvery Delta Farmers Protection Association, says “Fields damaged by oil leaks are never restored, and a meagre compensation after long-drawn complaints process is all that farmers see. Lands scarred by oil take years to recover.”
Incidents of gas leaks and the threat of fires in residential areas add to the concerns of neighbouring communities.
Farmers turn out in large numbers at public hearings to oppose ONGC’s proposals to sink new wells or expand operations. The concerns raised during public hearings highlight the lack of compliance to environmental regulations by ONGC, and a failure by the district administration and the Tamil Nadu Pollution Control Board to enforce the law. At an environmental public hearing conducted in 2014 for drilling wells in Nagapattinam, air and water pollution, groundwater depletion and increased incidence of respiratory diseases, farmland contamination and lapses in restoring damaged lands and awarding compensation were the most common concerns raised by local farmers.
In 2015, farmers from Tiruvarur demolished a shed being constructed by ONGC on paddy lands citing earlier gas leaks and the company’s poor track record.
Dhanapalan points out that “if people know and trust that the extraction of oil and gas can and will be done without harming the environment, they will not protest. The government must prove that hydrocarbons can be extracted safely by putting its existing operations in order, in restoring damaged farmlands and compensating affected farmers.”
Why did the people of Neduvasal not protest at the exploration stage itself?
The exploratory well in Neduvasal is actually not in Neduvasal but in a neighbouring village called Karukkakurichi, on five acres of land belonging to two brothers, Govinda Velar and Kulandai Velar. Banana and sugarcane were being cultivated on the land at the time. “They first came in 2008. But they never gave me any details about the project,” said Govinda Velar, a potter who lives near a kiln in a spacious tree-lined compound. “They said they were running some tests to see if there was petrol beneath our lands, and that it was only a short-term operation. We did not want to part with the land. But they were persistent and brought in the VAO and the tahsildar, who insisted that this was a government project. They took my signature on a piece of paper. I do not even have a copy of that letter,” he recalls.
The statutory environmental public hearing required to be held under the Environmental Impact Assessment Notification (EIA), 2006, has never been held for the Neduvasal exploration project. The environment ministry’s website, which claims to be up-to-date with all relevant information as part of its ease-of-doing-business and transparency initiatives, has neither an EIA nor an environmental clearance for the Neduvasal explorations.
In fact, only one environmental clearance mentions Pudukottai district. But that, too, is dated 2013 and refers to two locations in Pudukottai: Tiruvonam and Karambakudi. It does not mention Neduvasal.
What is known about the project?
The Neduvasal oil field reportedly has a seven-year mining lease that expires on December 31, 2019. The leased area is 10 sq. km from within which oil and gas can be extracted by the contractor. The recent award is part of the Indian government’s October 2015 Marginal Field Policy, aimed at inviting private sector participation in exploitation of marginal and small oil fields.
The project is not a coal-bed methane- or shale-gas-extraction project. So the use of hydraulic fracturing or fracking is unlikely – although it can only be ruled out pending further assessments. The proposal appears to be for a conventional oil and oil-associated gas extraction project with total extractable reserves of 430,000 tonnes of oil and oil-equivalent of gas. Speaking to The News Minute, Gem Laboratories has revealed that it has not made up its mind on the technology to be deployed to extract the hydrocarbons.
Onshore exploratory and production wells in the Cauvery delta are drilled to depths of between 1,750 m and 6,000 m. And the Neduvasal field, too, if developed will be drilled on to these depths.
How are conventional hydrocarbons extracted?
Before production wells are dug, developers sink a large number of appraisal wells to physically assess the extent and characteristics of the reservoir. If the Neduvasal project takes off, these wells will be located within the 10-sq.-km lease area.
The entire lease area will not be acquired; only areas around the proposed drill locations will be leased or acquired. Roughly five acres will be required for each drill site. Neither the locations nor the number of such wells are known at this point. Some wells may subsequently be abandoned or converted to other uses.
Production wells are usually dug to the base of a reservoir while appraisal wells may not go that deep. In the early days of production, when pressure differentials are high, oil/gas will gravitate to the low-pressure area at the bore and emerge to the surface on their own. Only 10-15% of the extractable reserves can be harvested at this primary stage.
Secondary recovery involves injecting high-pressure fluids to flush out the oil or gas trapped inside or in the interstices of the source rocks (sandstone, shale, etc.). New injection wells may need to be drilled for this purpose, or existing appraisal wells may be used. In ONGC’s Cauvery assets, “produced water” – a toxic by-product separated from the extracted hydrocarbons – is used for flushing.
Tertiary or enhanced recovery could involve fracturing the source rock using high-pressure fluids along with harder substances, like sand or aluminum beads that will wedge themselves between fissures, to facilitate hydrocarbon flow.
How is drilling done?
Drilling for exploration, appraisal or production have similar consequences. A drill site may require approximately five acres. The site preparation will involve flattening the land, laying access roads, laying concrete platforms to accommodate the drilling rigs and other infrastructure. Land-use change, alteration of drainage patterns, noise and air pollution are key concerns in this stage.
Once installed and the drilling has begun, the rig will operate on electricity from diesel generators 24×7 until the desired depth has been achieved. During this time, air pollution from generator sets and vehicular movement, and noise pollution, are key concerns.
A drilling fluid, usually water-based mud (WBM), is used to protect the structural integrity of the drilled hole, cool and lubricate the drill-bit and to evacuate the excavated drill cuttings (mud, sand and rock chips) to the surface. WBM is the least toxic of drilling fluids. Nevertheless, along with drill cuttings, it may be contaminated with trace levels of arsenic, cadmium, chromium and mercury depending on the geology of the area. This is a waste stream that requires careful disposal.
Drilling is followed by encasing the well with steel and concrete. The steel casing prevents the well from collapsing – and the concrete and steel also insulate the various water aquifers from the oil, gas and hydrocarbon-tainted brine that will emerge from underground once the well begins operating. However, in the time between drilling and encasing, there is a risk of contamination of exposed aquifers to chemicals or material that are part of drilling fluids.
What are the environmental effects likely to be encountered during the lifetime of a well?
Failed well sites have to be restored and returned to the land-use that prevailed prior to drilling – that is, agricultural use in the delta region. According to Dhanapalan, this is seldom done. Of the 600 or so wells that are part of the Cauvery assets, only 200 are producing wells. The remainder, barring a few that are used as injection wells, is abandoned. According to Dhanapalan, “None of these have been restored. At five acres a well, that translates to 2,000 acres of fertile land abandoned to become dense thickets of the dreaded karuvelam (Prosospis).” Karuvelam is a thorny weed that desiccates the land and has taken over the Tamil countryside.
The land surrounding the exploratory well in Karukkakurichi, near Neduvasal, is a case in point. While the surrounding lands have standing crops and healthy vegetation, the lands surrounding the idle well is carpeted by karuvelam.
Production wells also pose other challenges:
Produced water – When oil and gas are brought up to the surface, they emerge along with water that coexists with hydrocarbons in the reservoir. This is a significant waste stream by volume in oil-and-gas extraction operations. Where extraction is enhanced through flooding the reservoir with water, the quantities of produced water can be even greater. Depending on the age of the well and the nature of production, between two and nine barrels of produced water can be generated for every barrel of oil extracted.
Produced water is highly saline and corrosive, and will contain hydrocarbons like the toxic benzene, polycyclic aromatics, heavy metals and naturally occurring radioactive material like dissolved uranium, radon and radium. Pipelines or vessel interiors used to store or transport these effluents are prone to corroding and developing scales and salt deposits. The scales themselves tend to concentrate the toxins within the effluent, and ought to be handled as hazardous wastes.
ONGC’s delta operations claim to have 21 effluent treatment plants (ETP) to handle 70 million litres of produced water per day. Some of the treated water is reused in injection wells for waterflooding hydrocarbon reservoirs and the remainder disposed by pumping into old wells. Deepwell injection for disposal or for waterflooding are governed by dedicated rules in other countries and followed up with monitoring as well as informing the public of it.
However, produced water is dealt with casually in India. The EIA reports, which ought to dedicate entire sections to predicting and managing the impact of produced water, has nothing more than one passing reference to the waste stream. No information is available in the public domain about the performance of these ETPs either.
Groundwater contamination can occur if the well casing in production wells fail or wells collapse, exposing the aquifers to produced water and hydrocarbons emerging from the bore. They can also occur in abandoned or idle wells that may not be plugged, or where the plugs get damaged over time. Where and when this happens, hydrocarbons, gases and associated water can enter drinking-water aquifers. Idle wells that are not plugged should be subjected to routine checks for fractures in the casing or other defects. The exploratory well near Neduvasal has not been monitored since it was capped in 2009.
Groundwater, surface water and land contamination can also occur due to improper handling of waste streams – e.g., spills of produced water, temporary or long-term surface storage of produced water or oily wastes, leaks from crude oil pipelines, etc.
Air pollution can occur due to fugitive emissions or leaks. Volatile organic compounds (VOCs), including toxic chemicals like benzene (which causes leukaemia), ethylbenzene, xylene and toluene, can be mobilised in the air. Flaring or venting of gases is generally not a good practice as it represents a waste of the fuel that is to be harvested.
However, where this is done, ground-level air quality tends to deteriorate and pose a localised health hazard. Many of the VOCs can combine with nitrous oxides emitted from diesel exhaust to form ground-level ozone, a respiratory irritant.
Since methane – a potent greenhouse gas – is a major constituent of natural gas, venting the gases into the atmosphere can appreciably worsen global warming risks.
Blow-outs and explosions – Hazardous incidents such as blow-outs – caused by sudden surges in pressure inside the bore – result in gases erupting and exploding from the well mouth. These are the most hazardous incidents that can occur at a well site, and result in the discharge of large quantities of pollutants into the atmosphere. A single blow-out can last from a few minutes to several days. The 2010 Deepwater Horizon spill at BP’s oil installation in the Gulf of Mexico has been the worst blowout incident to date. It took five months to tame.
Blow-out risks are sought to be reduced by safety devices and good practices, and are relatively rare.
Land subsidence and salinity intrusion – Large-volume extraction of fluids, such as water or hydrocarbons, can result in land-subsidence. According to the US Geological Service, “This induced subsidence, which is either sub-regional or local in extent, has its greatest impact on flat coastal plains and wetlands near sea level where minor lowering of the land surface results in permanent inundation.”
This is particularly problematic for the delta region, which is already facing sea-water intrusion owing to rising sea levels, rampant sand-mining and the exploitation of underground resources like groundwater, apart from oil and gas.
Note: The sections on oil and gas extraction and environmental/health effects of hydrocarbon production has been sourced from several documents, including those already cited above. More here, here and here.
Nityanand Jayaraman is a Chennai-based writer and social activist.