US energy major Chevron said Tuesday it has started drilling its first exploration well for shale gas in Romania despite fierce opposition from local residents.
"Chevron can confirm that drilling activities have commenced at its exploration well site" near the village of Silistea in eastern Romania, a Chevron spokesman said.
"The drilling rig is expected to run until the well reaches a target depth of approximately 4000 metres" (13,000 feet), he added.
The company expects to search for shale gas for 3 to 5 years.
Chevron's attempts to establish its first exploration well in Romania were suspended twice at the end of 2013 owing to demonstrations by opponents of exploiting shale gas.
Many residents from this rural region of Romania fear the use of "fracking", a controversial extraction technique that consists of injecting water and chemicals deep into rock to release gas.
Chevron's exploration site is now a "special security zone" that is guarded by police with people passing nearby required to show identity papers.
Chevron says shale gas could prove crucial for Europe's energy security, especially as the crisis deepens in Ukraine, a key transit country for Russian natural gas supplies.
But environmental rights groups warn against the damaging impact on the environment.
Romania, unlike many countries in eastern and western Europe, is not heavily dependent on Russian supplies since it produces gas itself. Last year Romania imported from Russia only about 10 percent of its supplies, according to financial newspaper Ziarul Financiar.
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