Impacts on environment due to methane extraction in
IMPACTS ON ENVIRONMENT DUE
TO METHANE EXTRACTION IN THE
To create awareness among the students about
these kind of projects which will affect our
environment and life resource of all biotics.
This study will help people and organizations to
take account of damages to biodiversity, water
and land resources with CBM mining project.
The Kaveri delta coal-bed methane extraction
project is currently undertaken by Great Eastern Energy
Corporation Ltd (GEECL), a private company based in
The project aims to extract methane gas from coal-bed
using environmentally destructive method of hydraulic
fracturing in the Kaveri river basin.
The company received license to explore and extract
CBM from Thanjavur and Thrivarur districts which are
the major rice cultivating area of Tamil Nadu.
DETAILS ABOUT THE PROJECT:
On July 29, 2010 GEECL won CBM-IV type license
in a biding to explore and extract methane gas and
coal deposit in Mannarkudi block of Thrivarur
district in the Kaveri basin from the Ministry of
Petroleum and Natural Gas, Government of India.
Subsequently then the government of Tamil Nadu
issued petroleum exploration license (PEL) for area
covering 667 sq. km comprising Thanjavur and
DETAILS ABOUT THE PROJECT:
The company has a plan to drill more than 50
crore production wells of 500–1500 ft deep in the
In September 2012 the Union Ministry for
Environment and Forests (MOEF) issued
environmental clearance to the project.
Present state government of Tamil Nadu
temporarily suspended the project citing issues
raised by the farmer.
Planned region for Methane Extraction and already existing pipelines
WHAT IS COAL BED METHANE?
Coal bed methane is a natural gas by-product of
coal formation. During coal formation, organic
matter is chemically broken down into simple
Methane is a by-product of this breakdown.
Due to coal's porous nature, methane gas
produced during coal formation is absorbed into
the coal bed and held in place by the weight of
the surrounding groundwater.
HOW IS COAL BED METHANE
In order to commercially produce coal bed
methane, it is necessary to decrease the water
pressure within the coal bed.
When the pressure is decreased, the methane gas
naturally desorbs from the coal and migrates
through the coal bed.
IMPACTS OF METHANE EXTRACTION
Ground water depletion
Salt water intrusion
Surface water discharge
Large scale environmental effects
IMPACTS TO ENVIRONMENT
Ground Water Depletion.
One of the environmental effects of coal bed
methane extraction is the immense quantity of water
pumped out of the coal bed aquifers.
On average, approximately 12-15 gallons of water
per minute are pumped from each well. During the
initial phase of production, water is pumped at a very
Due to large quantity of groundwater extraction the
water table goes down results in groundwater
In several reported cases, local water wells have
gone dry after coal bed methane operations have
IMPACTS DUE TO SURFACE WATER
Surface discharge is the most common disposal
option for the extracted coal bed water, the
compositional characteristics of coal bed water
can have a tremendous impact on the surrounding
The quality of coal bed water varies considerably
from well to well and basin to basin, but, on
average, the deeper the coal bed, the more saline
the water becomes.
Other compositional elements typically seen in
extracted coal bed water include:
Major Cations (positively charged ions such as
sodium, potassium, magnesium, & calcium)
Major Anions (negatively charged ions such as
chlorine, sulphate, & hydrogen carbonate)
Trace Elements & Metals
(iron, manganese, barium, chromium, arsenic, sel
enium, & mercury)
Organics (hydrocarbons and additives).
The saline and sodic quality of coal bed water can
have catastrophic impacts on local agriculture
when discharged into local waterways.
The moderate to high levels of salt in coal bed
water can destroy soils and decrease crop
The salts gather in the root base of plants, making
it harder for the plants to extract water from the
soil and inhibiting growth.
One of the process used for methane extraction is
Hydraulic fracturing pumps a mixture of heavy
chemicals, water, sand and/or other materials
down an extraction well under extremely high
pressure in order to achieve the desired
Hydraulic fracturing raises serious concerns because
of the chemicals being used and their impact on the
If the coal bed aquifer is tributary to surface water or
other groundwater aquifers, chemical contamination
can spread into domestic, agricultural, and industrial
Some of the chemicals used for this process is
Lead, Uranium & Mercury which are all
Methane exists in the environment as a
greenhouse gas that has been linked to global
After carbon dioxide, methane is the second most
important greenhouse gas. Methane's warming
effect is 21 times greater than that of carbon
dioxide; however, it stays in the atmosphere for a
significantly shorter period of time.
As with all carbon based fossil fuels, burning
coal-bed methane releases carbon dioxide (CO2)
into the atmosphere and contributes to global
CBM (Coal-bed Methane) production also
involves release of methane into the
atmosphere, often referred to as fugitive methane.
Recent studies have found that fugitive release
may be as high as 4 to 9% of the total produced
by a project.