On Thursday night, cops went to the Island Pub at 238 City Island Ave. to check for underage drinking.
Once inside, they spotted an empty glassine envelope, the kind used to hold drugs, on the floor, police said.
The officers headed to the office over the bar to issue a summons to the owner, Gerard Pirraglia, 46, a 20-year FDNY veteran assigned to Engine Co. 48.
The cops found a small amount of cocaine in the office and arrested the off-duty firefighter for criminal possession of a controlled substance, a misdemeanor for which he was given a desk-appearance ticket, police said.
FDNY sources said Pirraglia was not in the bar when cops arrived and was called there by the bartender.
The firefighter could not be reached for comment yesterday.
