Surveillance video caught Sanitation Department supervisors buying six-packs of beer at a Brooklyn bodega and then heading back to their official car during last week’s blizzard chaos—but the footage has since been taped over, and officials want to know why, The Post has learned.

“DOI investigators immediately responded after it learned that a Post reporter heard allegations that sanitation workers had been inside a store buying beer instead of working,” said a Department of Investigation spokesman last night.

But when probers went to retrieve video of the men, they discovered that it had been “overridden,” he said.

Investigators are now looking into the circumstances of how that occurred, “taking steps to reconstruct [the video] . . . and are attempting to identify the sanitation workers,” the flak said.

The Post on Sunday revealed how the four men, clad in green Sanitation uniforms, strolled into the Ocean Mini Mart on 18th Avenue in Kensington on the evening of Dec. 26 as the snow was wreaking havoc on the city.

Video from inside the store, taped at around 8:20 p.m., shows a sanitation worker buying a six-pack of Corona Light—followed by another worker about a half-hour later who purchased a six-pack of Heineken Light.

They and their two colleagues are then seen hanging around outside the bodega laughing amid the piles of snow.

(Source: NY Post)