NEW YORK (Reuters) - The city of Buffalo, New York, banned the natural gas drilling technique of hydraulic fracturing on Tuesday, a largely symbolic vote that demonstrates concern about potential harm to groundwater from mining an abundant energy source.

The city council voted 9-0 to prohibit natural gas extraction including the process known as "fracking" in which chemicals, sand and water are blasted deep into the earth to fracture shale formations and allow gas to escape.

The ordinance also bans storing, transferring, treating or disposing of fracking waste within the city.

No such drilling projects had been planned in Buffalo, located in New York state, though city officials were concerned that fracking waste water from nearby operations was reaching the city sewer system.

Backers of the measure hope it will help build pressure against fracking, which environmentalists say endangers groundwater as a result of leaking chemicals.

Pittsburgh, Pennsylvania, has enacted a similar ban.

Industry supporters say fracking is proven to be safe and can provide a much-needed domestic energy source. For an index of shale gas companies, double-click on.

The Marcellus shale formation underlies much of Pennsylvania and parts of surrounding states including western New York. Geologists estimate it could meet U.S. natural gas demand for 20 years or more.

The U.S. Environmental Protection Agency is studying the impact of fracking and on Tuesday submitted a draft of its study to the agency's Science Advisory Board for review.

Initial findings from the study are expected to be made public by the end of 2012.

Also on Tuesday, New York's acting Department of Environmental Conservation Commissioner Joe Martens told the state legislature the agency's guidelines for allowing high-volume hydraulic fracturing in New York would be completed by about June 1, according to his spokesman.

The agency will then allow 30 days for public comment, the spokesman said.

(Reporting by Daniel Trotta and Edith Honan; Editing by David Gregorio)

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