By Ayesha Rascoe

WASHINGTON (Reuters) - The U.S. InteriorDepartment is taking longer to approve permits to drill for oiland gas offshore in shallow waters to ensure new safety rulesare met, a top department official said on Monday.

Michael Bromwich, head of Interior's Bureau of Ocean EnergyManagement, said there is no ban on shallow water activity, butit has taken more time to make sure drilling applications meetnew standards enacted since the BP oil spill in the Gulfof Mexico in April.

Following the BP drilling accident, the Interior Departmentenacted more stringent drilling rules, including a requirementthat companies certify they have working blowout preventers.

Interior said 13 drilling applications have been submittedsince new guidelines were issued on June 8. As of Sept. 10, thedepartment said five applications have been approved and eightare pending.

The department's six-month ban on exploratory drilling issupposed to apply only to water depths more than 500 feet (152metres), but drillers have complained that lengthy approvaltimes for new wells have led to a de facto moratorium even inshallow waters.

"I understand the frustration that people feel because weare not able to review and approve applications asexpeditiously as we have in the past," Bromwich said in astatement, following a meeting with shallow water drillers.

"But the central fact is that it has taken time to submitand verify the additional required information," he said.

Bromwich said the department would not approve applicationsuntil they fully comply with new requirements. "That will notmake everyone happy, but it is the right way to proceed," headded.

A coalition of shallow water drillers said they appreciatethe concerns about safety, but shallow water development doesnot pose the same risks as deepwater operations. They calledfor creation of a tiered review process based the amount ofrisk associated with different projects.

"BOEM must recognize that it cannot continue to shove asquare peg into a round hole by treating all offshore drillingoperations the same, disregarding history and geologicalfacts," said Jim Noe, Executive Director of the Shallow WaterEnergy Security Coalition.

Noe said 15 of the 46 available shallow water rigs havebeen idled without permits and warned the approval processwould need to be speeded up to avoid "economic calamity." (Editing by Marguerita Choy)