Environmental Engineering Reference
In-Depth Information
wells in the Weiyuan Block. PetroChina plans to drill more than 100 hori-
zontal shale gas development wells in the next two years in the Sichuan
Basin. These developments indicate that China should fulfill its shale gas
development plan in several years. In June 2013, CNPC announced that it
has started building the country's first dedicated shale-gas pipeline in
Sichuan province - more pipelines will be built with both government
support and private capital.
Recently, the new third plenary session of the 18th Communist Party of
China (CPC) Central Committee issued a detailed reform of the fiscal system
to loosen its grip on capital controls and allow private capital to play a
greater role in China's economy. Private and foreign investment will also be
welcomed to help develop shale gas in China. Despite environmentalists'
fears, the possibility of contamination is small since shale rocks are gener-
ally located much deeper than water aquifers and there are many non-
permeable rock layers between water aquifers and shale-rock formations.
China's shale gas is at least 2000 metres underground, i.e. significantly
deeper than shallow aquifers for drinking water and separated from
underground water by impermeable rock. Several thousand feet of cement
also seals off the annular space between the wellbore wall and the outside of
the well casing to prevent shale gas and formation fluids migrating up to the
freshwater aquifer. Even though a recent study shows that groundwater
contamination was caused by shale gas production in the US, 16 this was
found to be mainly due to poor well integrity or poor cementing. China can
use this information as a wake-up call to monitor the careful drilling and
stimulation of shale gas development. 17 Experiences learned from the US
will help China to extract shale gas effectively and environmentally by
implementing regulations. Indeed, China has scrutinised the well planning
and environmental protection plans; issued a ban on direct emissions of
waste gas; prescribed a more ecient use of water and energy, and a timely
rehabilitation of land, etc.
9 Conclusions
Shale gas production is an indispensable opportunity for China to obtain
energy security to power its booming economy and reduce air pollution.
Even though China's shales present challenges for hydraulic fracturing due
to their complex geological settings, sub-surface and ground conditions, as
well as the need for the development specialist technologies and a suitable
infrastructure, they still offer a very promising prospect. China's shales
represent the largest shale gas resources in the world, and low land costs,
relatively cheap labour, governmental support and policies, stronger en-
vironmental regulations and improving technologies favour their exploit-
ation. Whilst shale gas developments in Poland have proven disappointing
and in France have faced a number of policy obstacles, shale gas develop-
ments in China have made promising progress with new breakthroughs in
indigenous and foreign technology, and the commercial production of shale
 
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