* Commission to announce shale stance around year-end
* Some in industry want regulatory framework
* Uncertainty over methane emissions
BRUSSELS, Oct 3 (Reuters) - European policy-makers will decide by the end of the year whether they need tailor-made rules to cover the development of shale gas reserves, a senior official said on Thursday.
Until now, the European Commission, the EU executive, has said existing environmental law is adequate for the early stages of shale gas exploration in Europe.
Jos Delbeke, director general of the Commission's climate action service, said he expected an announcement around the end of the year as part of a package of future energy and climate policies, addressing 2030 energy targets, energy costs and also shale gas.
"We will deal with shale gas as part of the 2030 questions that are on the table," Delbeke told a debate on shale gas.
"We are doing an analysis of where there may be gaps in our legislation. There may be legislation from the EU."
Even if the Commission does go as far as a legislative proposal, elections to the European Parliament next year followed by a new cast of EU commissioners mean it would almost certainly not be finalised before 2015.
Shale gas development in the European Union is highly controversial.
Industry argues it can curb greenhouse gases, lower energy costs and shore up indigenous supplies. Some in the business, such as Chevron, have said a regulatory framework would be helpful.
But environmental campaigners and commission officials also highlight the complexity of its development in Europe.
Delbeke cited the issues of Europe's population density, environmental concerns and the need to ensure that it was complementary to renewable energy, but did not displace it.
"The impact has been very negative (for Europe). The U.S. has substituted coal for gas and superfluous coal has come to Europe," he said of the shale gas revolution in the United States.
Among the environmental concerns is the release of methane, which is an extremely potent greenhouse gas.
Some research has said methane leaks from shale wells could mean shale gas is even worse than coal for the environment, but uncertainty over how much is emitted is very great.
A new study for the University of Texas at Austin, United States, presented in Brussels on Thursday found emissions from some types of pneumatic devices used in shale gas extraction, were higher than previously thought.
Overall emissions, however, were comparable to the most recent estimates from the U.S. Environmental Protection Agency.
Drew Nelson, a senior manager at the Environmental Defense Fund (EDF), a U.S. advocacy group, said the EDF was supporting 16 separate studies to try to create more certainty about methane emission levels.